[PATCH 0/3] drm: Split drm_modeset_helper_vtables.h

[PATCH 0/3] drm: Split drm_modeset_helper_vtables.h

[Geert Uytterhoeven]

	Hi all,

<drm/drm_modeset_helper_vtables.h> is the second largest header file in
the DRM subsystem, and declares helpers vtables for various DRM
components.  Several vtables contain methods with the same name, and all
but one vtable do not fit on the screen, making it hard to navigate to
the actual method one is interested in.

Hence this patch series splits <drm/drm_modeset_helper_vtables.h> in
multiple header files, one per DRM component, preceded by a few spelling
fix this to avoid checkpatch warnings.  A future patch could replace
inclusion of <drm/drm_modeset_helper_vtables.h> by inclusion of one or
more of the new files, to reduce compilation time.

I marked the last patch RFC, the first two patches can be applied
immediately.

Thanks for your comments!

Geert Uytterhoeven (3):
  drm: Spelling s/hardward/hardware/g
  drm: Spelling s/preceeding/preceding/g
  [RFC] drm: Split drm_modeset_helper_vtables.h

 drivers/gpu/drm/drm_atomic_helper.c         |    4 +-
 include/drm/drm_bridge.h                    |    2 +-
 include/drm/drm_connector_helper_vtable.h   |  364 +++++
 include/drm/drm_crtc_helper_vtable.h        |  483 ++++++
 include/drm/drm_encoder_helper_vtable.h     |  381 +++++
 include/drm/drm_mode_config_helper_vtable.h |   97 ++
 include/drm/drm_modeset_helper_vtables.h    | 1466 +------------------
 include/drm/drm_plane_helper_vtable.h       |  297 ++++
 8 files changed, 1630 insertions(+), 1464 deletions(-)
 create mode 100644 include/drm/drm_connector_helper_vtable.h
 create mode 100644 include/drm/drm_crtc_helper_vtable.h
 create mode 100644 include/drm/drm_encoder_helper_vtable.h
 create mode 100644 include/drm/drm_mode_config_helper_vtable.h
 create mode 100644 include/drm/drm_plane_helper_vtable.h

-- 
2.34.1

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

[PATCH 1/3] drm: Spelling s/hardward/hardware/g

[Geert Uytterhoeven]

Fix misspellings of "hardware".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 include/drm/drm_bridge.h                 | 2 +-
 include/drm/drm_modeset_helper_vtables.h | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index cfb7dcdb66c4b0b5..05b360a4357fed01 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -107,7 +107,7 @@ struct drm_bridge_funcs {
 	 * Since this function is both called from the check phase of an atomic
 	 * commit, and the mode validation in the probe paths it is not allowed
 	 * to look at anything else but the passed-in mode, and validate it
-	 * against configuration-invariant hardward constraints. Any further
+	 * against configuration-invariant hardware constraints. Any further
 	 * limits which depend upon the configuration can only be checked in
 	 * @mode_fixup.
 	 *
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index e3c3ac615909474b..bbc516f313913254 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -134,7 +134,7 @@ struct drm_crtc_helper_funcs {
 	 * Since this function is both called from the check phase of an atomic
 	 * commit, and the mode validation in the probe paths it is not allowed
 	 * to look at anything else but the passed-in mode, and validate it
-	 * against configuration-invariant hardward constraints. Any further
+	 * against configuration-invariant hardware constraints. Any further
 	 * limits which depend upon the configuration can only be checked in
 	 * @mode_fixup or @atomic_check.
 	 *
@@ -550,7 +550,7 @@ struct drm_encoder_helper_funcs {
 	 * Since this function is both called from the check phase of an atomic
 	 * commit, and the mode validation in the probe paths it is not allowed
 	 * to look at anything else but the passed-in mode, and validate it
-	 * against configuration-invariant hardward constraints. Any further
+	 * against configuration-invariant hardware constraints. Any further
 	 * limits which depend upon the configuration can only be checked in
 	 * @mode_fixup or @atomic_check.
 	 *
-- 
2.34.1

Re: [PATCH 1/3] drm: Spelling s/hardward/hardware/g

[Neil Armstrong]

Le 28/09/2023 à 14:16, Geert Uytterhoeven a écrit :
> Fix misspellings of "hardware".
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>   include/drm/drm_bridge.h                 | 2 +-
>   include/drm/drm_modeset_helper_vtables.h | 4 ++--
>   2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
> index cfb7dcdb66c4b0b5..05b360a4357fed01 100644
> --- a/include/drm/drm_bridge.h
> +++ b/include/drm/drm_bridge.h
> @@ -107,7 +107,7 @@ struct drm_bridge_funcs {
>   	 * Since this function is both called from the check phase of an atomic
>   	 * commit, and the mode validation in the probe paths it is not allowed
>   	 * to look at anything else but the passed-in mode, and validate it
> -	 * against configuration-invariant hardward constraints. Any further
> +	 * against configuration-invariant hardware constraints. Any further
>   	 * limits which depend upon the configuration can only be checked in
>   	 * @mode_fixup.
>   	 *
> diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
> index e3c3ac615909474b..bbc516f313913254 100644
> --- a/include/drm/drm_modeset_helper_vtables.h
> +++ b/include/drm/drm_modeset_helper_vtables.h
> @@ -134,7 +134,7 @@ struct drm_crtc_helper_funcs {
>   	 * Since this function is both called from the check phase of an atomic
>   	 * commit, and the mode validation in the probe paths it is not allowed
>   	 * to look at anything else but the passed-in mode, and validate it
> -	 * against configuration-invariant hardward constraints. Any further
> +	 * against configuration-invariant hardware constraints. Any further
>   	 * limits which depend upon the configuration can only be checked in
>   	 * @mode_fixup or @atomic_check.
>   	 *
> @@ -550,7 +550,7 @@ struct drm_encoder_helper_funcs {
>   	 * Since this function is both called from the check phase of an atomic
>   	 * commit, and the mode validation in the probe paths it is not allowed
>   	 * to look at anything else but the passed-in mode, and validate it
> -	 * against configuration-invariant hardward constraints. Any further
> +	 * against configuration-invariant hardware constraints. Any further
>   	 * limits which depend upon the configuration can only be checked in
>   	 * @mode_fixup or @atomic_check.
>   	 *

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

Re: [PATCH 1/3] drm: Spelling s/hardward/hardware/g

[Thomas Zimmermann]

[-- Attachment #1.1: Type: text/plain, Size: 2697 bytes --]



Am 28.09.23 um 14:16 schrieb Geert Uytterhoeven:
> Fix misspellings of "hardware".
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>

> ---
>   include/drm/drm_bridge.h                 | 2 +-
>   include/drm/drm_modeset_helper_vtables.h | 4 ++--
>   2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
> index cfb7dcdb66c4b0b5..05b360a4357fed01 100644
> --- a/include/drm/drm_bridge.h
> +++ b/include/drm/drm_bridge.h
> @@ -107,7 +107,7 @@ struct drm_bridge_funcs {
>   	 * Since this function is both called from the check phase of an atomic
>   	 * commit, and the mode validation in the probe paths it is not allowed
>   	 * to look at anything else but the passed-in mode, and validate it
> -	 * against configuration-invariant hardward constraints. Any further
> +	 * against configuration-invariant hardware constraints. Any further
>   	 * limits which depend upon the configuration can only be checked in
>   	 * @mode_fixup.
>   	 *
> diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
> index e3c3ac615909474b..bbc516f313913254 100644
> --- a/include/drm/drm_modeset_helper_vtables.h
> +++ b/include/drm/drm_modeset_helper_vtables.h
> @@ -134,7 +134,7 @@ struct drm_crtc_helper_funcs {
>   	 * Since this function is both called from the check phase of an atomic
>   	 * commit, and the mode validation in the probe paths it is not allowed
>   	 * to look at anything else but the passed-in mode, and validate it
> -	 * against configuration-invariant hardward constraints. Any further
> +	 * against configuration-invariant hardware constraints. Any further
>   	 * limits which depend upon the configuration can only be checked in
>   	 * @mode_fixup or @atomic_check.
>   	 *
> @@ -550,7 +550,7 @@ struct drm_encoder_helper_funcs {
>   	 * Since this function is both called from the check phase of an atomic
>   	 * commit, and the mode validation in the probe paths it is not allowed
>   	 * to look at anything else but the passed-in mode, and validate it
> -	 * against configuration-invariant hardward constraints. Any further
> +	 * against configuration-invariant hardware constraints. Any further
>   	 * limits which depend upon the configuration can only be checked in
>   	 * @mode_fixup or @atomic_check.
>   	 *

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

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[PATCH 2/3] drm: Spelling s/preceeding/preceding/g

[Geert Uytterhoeven]

Fix misspellings of "preceding".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/gpu/drm/drm_atomic_helper.c      | 4 ++--
 include/drm/drm_modeset_helper_vtables.h | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 71d3993971075eea..10aadd324cc370ee 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -2373,10 +2373,10 @@ int drm_atomic_helper_setup_commit(struct drm_atomic_state *state,
 EXPORT_SYMBOL(drm_atomic_helper_setup_commit);
 
 /**
- * drm_atomic_helper_wait_for_dependencies - wait for required preceeding commits
+ * drm_atomic_helper_wait_for_dependencies - wait for required preceding commits
  * @old_state: atomic state object with old state structures
  *
- * This function waits for all preceeding commits that touch the same CRTC as
+ * This function waits for all preceding commits that touch the same CRTC as
  * @old_state to both be committed to the hardware (as signalled by
  * drm_atomic_helper_commit_hw_done()) and executed by the hardware (as signalled
  * by calling drm_crtc_send_vblank_event() on the &drm_crtc_state.event).
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index bbc516f313913254..91860372be6c064e 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -1464,7 +1464,7 @@ struct drm_mode_config_helper_funcs {
 	 * swapped into the various state pointers. The passed in state
 	 * therefore contains copies of the old/previous state. This hook should
 	 * commit the new state into hardware. Note that the helpers have
-	 * already waited for preceeding atomic commits and fences, but drivers
+	 * already waited for preceding atomic commits and fences, but drivers
 	 * can add more waiting calls at the start of their implementation, e.g.
 	 * to wait for driver-internal request for implicit syncing, before
 	 * starting to commit the update to the hardware.
-- 
2.34.1

Re: [PATCH 2/3] drm: Spelling s/preceeding/preceding/g

[Thomas Zimmermann]

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Am 28.09.23 um 14:16 schrieb Geert Uytterhoeven:
> Fix misspellings of "preceding".
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>

> ---
>   drivers/gpu/drm/drm_atomic_helper.c      | 4 ++--
>   include/drm/drm_modeset_helper_vtables.h | 2 +-
>   2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
> index 71d3993971075eea..10aadd324cc370ee 100644
> --- a/drivers/gpu/drm/drm_atomic_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_helper.c
> @@ -2373,10 +2373,10 @@ int drm_atomic_helper_setup_commit(struct drm_atomic_state *state,
>   EXPORT_SYMBOL(drm_atomic_helper_setup_commit);
>   
>   /**
> - * drm_atomic_helper_wait_for_dependencies - wait for required preceeding commits
> + * drm_atomic_helper_wait_for_dependencies - wait for required preceding commits
>    * @old_state: atomic state object with old state structures
>    *
> - * This function waits for all preceeding commits that touch the same CRTC as
> + * This function waits for all preceding commits that touch the same CRTC as
>    * @old_state to both be committed to the hardware (as signalled by
>    * drm_atomic_helper_commit_hw_done()) and executed by the hardware (as signalled
>    * by calling drm_crtc_send_vblank_event() on the &drm_crtc_state.event).
> diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
> index bbc516f313913254..91860372be6c064e 100644
> --- a/include/drm/drm_modeset_helper_vtables.h
> +++ b/include/drm/drm_modeset_helper_vtables.h
> @@ -1464,7 +1464,7 @@ struct drm_mode_config_helper_funcs {
>   	 * swapped into the various state pointers. The passed in state
>   	 * therefore contains copies of the old/previous state. This hook should
>   	 * commit the new state into hardware. Note that the helpers have
> -	 * already waited for preceeding atomic commits and fences, but drivers
> +	 * already waited for preceding atomic commits and fences, but drivers
>   	 * can add more waiting calls at the start of their implementation, e.g.
>   	 * to wait for driver-internal request for implicit syncing, before
>   	 * starting to commit the update to the hardware.

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

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[PATCH/RFC 3/3] drm: Split drm_modeset_helper_vtables.h

[Geert Uytterhoeven]

<drm/drm_modeset_helper_vtables.h> is the second largest header file in
the DRM subsystem, and declares helpers vtables for various DRM
components.  Several vtables contain methods with the same name, and all
but one vtable do not fit on the screen, making it hard to navigate to
the actual method one is interested in.

Make it easier for the casual reviewer to keep track by splitting
<drm/drm_modeset_helper_vtables.h> in multiple header files, one per DRM
component.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
RFC, a future patch could replace inclusion of
<drm/drm_modeset_helper_vtables.h> by inclusion of one or more of the
new files, and reduce compilation time.
---
 include/drm/drm_connector_helper_vtable.h   |  364 +++++
 include/drm/drm_crtc_helper_vtable.h        |  483 ++++++
 include/drm/drm_encoder_helper_vtable.h     |  381 +++++
 include/drm/drm_mode_config_helper_vtable.h |   97 ++
 include/drm/drm_modeset_helper_vtables.h    | 1466 +------------------
 include/drm/drm_plane_helper_vtable.h       |  297 ++++
 6 files changed, 1627 insertions(+), 1461 deletions(-)
 create mode 100644 include/drm/drm_connector_helper_vtable.h
 create mode 100644 include/drm/drm_crtc_helper_vtable.h
 create mode 100644 include/drm/drm_encoder_helper_vtable.h
 create mode 100644 include/drm/drm_mode_config_helper_vtable.h
 create mode 100644 include/drm/drm_plane_helper_vtable.h

diff --git a/include/drm/drm_connector_helper_vtable.h b/include/drm/drm_connector_helper_vtable.h
new file mode 100644
index 0000000000000000..92db9784e4e37e02
--- /dev/null
+++ b/include/drm/drm_connector_helper_vtable.h
@@ -0,0 +1,364 @@
+/*
+ * Copyright © 2006 Keith Packard
+ * Copyright © 2007-2008 Dave Airlie
+ * Copyright © 2007-2008 Intel Corporation
+ *   Jesse Barnes <jesse.barnes@intel.com>
+ * Copyright © 2011-2013 Intel Corporation
+ * Copyright © 2015 Intel Corporation
+ *   Daniel Vetter <daniel.vetter@ffwll.ch>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __DRM_CONNECTOR_HELPER_VTABLE_H__
+#define __DRM_CONNECTOR_HELPER_VTABLE_H__
+
+struct drm_writeback_connector;
+struct drm_writeback_job;
+
+/**
+ * struct drm_connector_helper_funcs - helper operations for connectors
+ *
+ * These functions are used by the atomic and legacy modeset helpers and by the
+ * probe helpers.
+ */
+struct drm_connector_helper_funcs {
+	/**
+	 * @get_modes:
+	 *
+	 * This function should fill in all modes currently valid for the sink
+	 * into the &drm_connector.probed_modes list. It should also update the
+	 * EDID property by calling drm_connector_update_edid_property().
+	 *
+	 * The usual way to implement this is to cache the EDID retrieved in the
+	 * probe callback somewhere in the driver-private connector structure.
+	 * In this function drivers then parse the modes in the EDID and add
+	 * them by calling drm_add_edid_modes(). But connectors that drive a
+	 * fixed panel can also manually add specific modes using
+	 * drm_mode_probed_add(). Drivers which manually add modes should also
+	 * make sure that the &drm_connector.display_info,
+	 * &drm_connector.width_mm and &drm_connector.height_mm fields are
+	 * filled in.
+	 *
+	 * Note that the caller function will automatically add standard VESA
+	 * DMT modes up to 1024x768 if the .get_modes() helper operation returns
+	 * no mode and if the connector status is connector_status_connected or
+	 * connector_status_unknown. There is no need to call
+	 * drm_add_modes_noedid() manually in that case.
+	 *
+	 * Virtual drivers that just want some standard VESA mode with a given
+	 * resolution can call drm_add_modes_noedid(), and mark the preferred
+	 * one using drm_set_preferred_mode().
+	 *
+	 * This function is only called after the @detect hook has indicated
+	 * that a sink is connected and when the EDID isn't overridden through
+	 * sysfs or the kernel commandline.
+	 *
+	 * This callback is used by the probe helpers in e.g.
+	 * drm_helper_probe_single_connector_modes().
+	 *
+	 * To avoid races with concurrent connector state updates, the helper
+	 * libraries always call this with the &drm_mode_config.connection_mutex
+	 * held. Because of this it's safe to inspect &drm_connector->state.
+	 *
+	 * RETURNS:
+	 *
+	 * The number of modes added by calling drm_mode_probed_add().
+	 */
+	int (*get_modes)(struct drm_connector *connector);
+
+	/**
+	 * @detect_ctx:
+	 *
+	 * Check to see if anything is attached to the connector. The parameter
+	 * force is set to false whilst polling, true when checking the
+	 * connector due to a user request. force can be used by the driver to
+	 * avoid expensive, destructive operations during automated probing.
+	 *
+	 * This callback is optional, if not implemented the connector will be
+	 * considered as always being attached.
+	 *
+	 * This is the atomic version of &drm_connector_funcs.detect.
+	 *
+	 * To avoid races against concurrent connector state updates, the
+	 * helper libraries always call this with ctx set to a valid context,
+	 * and &drm_mode_config.connection_mutex will always be locked with
+	 * the ctx parameter set to this ctx. This allows taking additional
+	 * locks as required.
+	 *
+	 * RETURNS:
+	 *
+	 * &drm_connector_status indicating the connector's status,
+	 * or the error code returned by drm_modeset_lock(), -EDEADLK.
+	 */
+	int (*detect_ctx)(struct drm_connector *connector,
+			  struct drm_modeset_acquire_ctx *ctx,
+			  bool force);
+
+	/**
+	 * @mode_valid:
+	 *
+	 * Callback to validate a mode for a connector, irrespective of the
+	 * specific display configuration.
+	 *
+	 * This callback is used by the probe helpers to filter the mode list
+	 * (which is usually derived from the EDID data block from the sink).
+	 * See e.g. drm_helper_probe_single_connector_modes().
+	 *
+	 * This function is optional.
+	 *
+	 * NOTE:
+	 *
+	 * This only filters the mode list supplied to userspace in the
+	 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid,
+	 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid,
+	 * which are also called by the atomic helpers from
+	 * drm_atomic_helper_check_modeset(). This allows userspace to force and
+	 * ignore sink constraint (like the pixel clock limits in the screen's
+	 * EDID), which is useful for e.g. testing, or working around a broken
+	 * EDID. Any source hardware constraint (which always need to be
+	 * enforced) therefore should be checked in one of the above callbacks,
+	 * and not this one here.
+	 *
+	 * To avoid races with concurrent connector state updates, the helper
+	 * libraries always call this with the &drm_mode_config.connection_mutex
+	 * held. Because of this it's safe to inspect &drm_connector->state.
+	 *
+	 * RETURNS:
+	 *
+	 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum
+	 * drm_mode_status.
+	 */
+	enum drm_mode_status (*mode_valid)(struct drm_connector *connector,
+					   struct drm_display_mode *mode);
+
+	/**
+	 * @mode_valid_ctx:
+	 *
+	 * Callback to validate a mode for a connector, irrespective of the
+	 * specific display configuration.
+	 *
+	 * This callback is used by the probe helpers to filter the mode list
+	 * (which is usually derived from the EDID data block from the sink).
+	 * See e.g. drm_helper_probe_single_connector_modes().
+	 *
+	 * This function is optional, and is the atomic version of
+	 * &drm_connector_helper_funcs.mode_valid.
+	 *
+	 * To allow for accessing the atomic state of modesetting objects, the
+	 * helper libraries always call this with ctx set to a valid context,
+	 * and &drm_mode_config.connection_mutex will always be locked with
+	 * the ctx parameter set to @ctx. This allows for taking additional
+	 * locks as required.
+	 *
+	 * Even though additional locks may be acquired, this callback is
+	 * still expected not to take any constraints into account which would
+	 * be influenced by the currently set display state - such constraints
+	 * should be handled in the driver's atomic check. For example, if a
+	 * connector shares display bandwidth with other connectors then it
+	 * would be ok to validate the minimum bandwidth requirement of a mode
+	 * against the maximum possible bandwidth of the connector. But it
+	 * wouldn't be ok to take the current bandwidth usage of other
+	 * connectors into account, as this would change depending on the
+	 * display state.
+	 *
+	 * Returns:
+	 * 0 if &drm_connector_helper_funcs.mode_valid_ctx succeeded and wrote
+	 * the &enum drm_mode_status value to @status, or a negative error
+	 * code otherwise.
+	 *
+	 */
+	int (*mode_valid_ctx)(struct drm_connector *connector,
+			      struct drm_display_mode *mode,
+			      struct drm_modeset_acquire_ctx *ctx,
+			      enum drm_mode_status *status);
+
+	/**
+	 * @best_encoder:
+	 *
+	 * This function should select the best encoder for the given connector.
+	 *
+	 * This function is used by both the atomic helpers (in the
+	 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC
+	 * helpers.
+	 *
+	 * NOTE:
+	 *
+	 * In atomic drivers this function is called in the check phase of an
+	 * atomic update. The driver is not allowed to change or inspect
+	 * anything outside of arguments passed-in. Atomic drivers which need to
+	 * inspect dynamic configuration state should instead use
+	 * @atomic_best_encoder.
+	 *
+	 * You can leave this function to NULL if the connector is only
+	 * attached to a single encoder. In this case, the core will call
+	 * drm_connector_get_single_encoder() for you.
+	 *
+	 * RETURNS:
+	 *
+	 * Encoder that should be used for the given connector and connector
+	 * state, or NULL if no suitable encoder exists. Note that the helpers
+	 * will ensure that encoders aren't used twice, drivers should not check
+	 * for this.
+	 */
+	struct drm_encoder *(*best_encoder)(struct drm_connector *connector);
+
+	/**
+	 * @atomic_best_encoder:
+	 *
+	 * This is the atomic version of @best_encoder for atomic drivers which
+	 * need to select the best encoder depending upon the desired
+	 * configuration and can't select it statically.
+	 *
+	 * This function is used by drm_atomic_helper_check_modeset().
+	 * If it is not implemented, the core will fallback to @best_encoder
+	 * (or drm_connector_get_single_encoder() if @best_encoder is NULL).
+	 *
+	 * NOTE:
+	 *
+	 * This function is called in the check phase of an atomic update. The
+	 * driver is not allowed to change anything outside of the
+	 * &drm_atomic_state update tracking structure passed in.
+	 *
+	 * RETURNS:
+	 *
+	 * Encoder that should be used for the given connector and connector
+	 * state, or NULL if no suitable encoder exists. Note that the helpers
+	 * will ensure that encoders aren't used twice, drivers should not check
+	 * for this.
+	 */
+	struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector,
+						   struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_check:
+	 *
+	 * This hook is used to validate connector state. This function is
+	 * called from &drm_atomic_helper_check_modeset, and is called when
+	 * a connector property is set, or a modeset on the crtc is forced.
+	 *
+	 * Because &drm_atomic_helper_check_modeset may be called multiple times,
+	 * this function should handle being called multiple times as well.
+	 *
+	 * This function is also allowed to inspect any other object's state and
+	 * can add more state objects to the atomic commit if needed. Care must
+	 * be taken though to ensure that state check and compute functions for
+	 * these added states are all called, and derived state in other objects
+	 * all updated. Again the recommendation is to just call check helpers
+	 * until a maximal configuration is reached.
+	 *
+	 * NOTE:
+	 *
+	 * This function is called in the check phase of an atomic update. The
+	 * driver is not allowed to change anything outside of the free-standing
+	 * state objects passed-in or assembled in the overall &drm_atomic_state
+	 * update tracking structure.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success, -EINVAL if the state or the transition can't be
+	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
+	 * attempt to obtain another state object ran into a &drm_modeset_lock
+	 * deadlock.
+	 */
+	int (*atomic_check)(struct drm_connector *connector,
+			    struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_commit:
+	 *
+	 * This hook is to be used by drivers implementing writeback connectors
+	 * that need a point when to commit the writeback job to the hardware.
+	 * The writeback_job to commit is available in the new connector state,
+	 * in &drm_connector_state.writeback_job.
+	 *
+	 * This hook is optional.
+	 *
+	 * This callback is used by the atomic modeset helpers.
+	 */
+	void (*atomic_commit)(struct drm_connector *connector,
+			      struct drm_atomic_state *state);
+
+	/**
+	 * @prepare_writeback_job:
+	 *
+	 * As writeback jobs contain a framebuffer, drivers may need to
+	 * prepare and clean them up the same way they can prepare and
+	 * clean up framebuffers for planes. This optional connector operation
+	 * is used to support the preparation of writeback jobs. The job
+	 * prepare operation is called from drm_atomic_helper_prepare_planes()
+	 * for struct &drm_writeback_connector connectors only.
+	 *
+	 * This operation is optional.
+	 *
+	 * This callback is used by the atomic modeset helpers.
+	 */
+	int (*prepare_writeback_job)(struct drm_writeback_connector *connector,
+				     struct drm_writeback_job *job);
+	/**
+	 * @cleanup_writeback_job:
+	 *
+	 * This optional connector operation is used to support the
+	 * cleanup of writeback jobs. The job cleanup operation is called
+	 * from the existing drm_writeback_cleanup_job() function, invoked
+	 * both when destroying the job as part of an aborted commit, or when
+	 * the job completes.
+	 *
+	 * This operation is optional.
+	 *
+	 * This callback is used by the atomic modeset helpers.
+	 */
+	void (*cleanup_writeback_job)(struct drm_writeback_connector *connector,
+				      struct drm_writeback_job *job);
+
+	/**
+	 * @enable_hpd:
+	 *
+	 * Enable hot-plug detection for the connector.
+	 *
+	 * This operation is optional.
+	 *
+	 * This callback is used by the drm_kms_helper_poll_enable() helpers.
+	 */
+	void (*enable_hpd)(struct drm_connector *connector);
+
+	/**
+	 * @disable_hpd:
+	 *
+	 * Disable hot-plug detection for the connector.
+	 *
+	 * This operation is optional.
+	 *
+	 * This callback is used by the drm_kms_helper_poll_disable() helpers.
+	 */
+	void (*disable_hpd)(struct drm_connector *connector);
+};
+
+/**
+ * drm_connector_helper_add - sets the helper vtable for a connector
+ * @connector: DRM connector
+ * @funcs: helper vtable to set for @connector
+ */
+static inline void drm_connector_helper_add(struct drm_connector *connector,
+					    const struct drm_connector_helper_funcs *funcs)
+{
+	connector->helper_private = funcs;
+}
+
+#endif /* __DRM_CONNECTOR_HELPER_VTABLE_H__ */
diff --git a/include/drm/drm_crtc_helper_vtable.h b/include/drm/drm_crtc_helper_vtable.h
new file mode 100644
index 0000000000000000..6dc5d4d7af494a1b
--- /dev/null
+++ b/include/drm/drm_crtc_helper_vtable.h
@@ -0,0 +1,483 @@
+/*
+ * Copyright © 2006 Keith Packard
+ * Copyright © 2007-2008 Dave Airlie
+ * Copyright © 2007-2008 Intel Corporation
+ *   Jesse Barnes <jesse.barnes@intel.com>
+ * Copyright © 2011-2013 Intel Corporation
+ * Copyright © 2015 Intel Corporation
+ *   Daniel Vetter <daniel.vetter@ffwll.ch>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __DRM_CRTC_HELPER_VTABLE_H__
+#define __DRM_CRTC_HELPER_VTABLE_H__
+
+enum mode_set_atomic {
+	LEAVE_ATOMIC_MODE_SET,
+	ENTER_ATOMIC_MODE_SET,
+};
+
+/**
+ * struct drm_crtc_helper_funcs - helper operations for CRTCs
+ *
+ * These hooks are used by the legacy CRTC helpers and the new atomic
+ * modesetting helpers.
+ */
+struct drm_crtc_helper_funcs {
+	/**
+	 * @dpms:
+	 *
+	 * Callback to control power levels on the CRTC.  If the mode passed in
+	 * is unsupported, the provider must use the next lowest power level.
+	 * This is used by the legacy CRTC helpers to implement DPMS
+	 * functionality in drm_helper_connector_dpms().
+	 *
+	 * This callback is also used to disable a CRTC by calling it with
+	 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
+	 *
+	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
+	 * also support using this hook for enabling and disabling a CRTC to
+	 * facilitate transitions to atomic, but it is deprecated. Instead
+	 * @atomic_enable and @atomic_disable should be used.
+	 */
+	void (*dpms)(struct drm_crtc *crtc, int mode);
+
+	/**
+	 * @prepare:
+	 *
+	 * This callback should prepare the CRTC for a subsequent modeset, which
+	 * in practice means the driver should disable the CRTC if it is
+	 * running. Most drivers ended up implementing this by calling their
+	 * @dpms hook with DRM_MODE_DPMS_OFF.
+	 *
+	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
+	 * also support using this hook for disabling a CRTC to facilitate
+	 * transitions to atomic, but it is deprecated. Instead @atomic_disable
+	 * should be used.
+	 */
+	void (*prepare)(struct drm_crtc *crtc);
+
+	/**
+	 * @commit:
+	 *
+	 * This callback should commit the new mode on the CRTC after a modeset,
+	 * which in practice means the driver should enable the CRTC.  Most
+	 * drivers ended up implementing this by calling their @dpms hook with
+	 * DRM_MODE_DPMS_ON.
+	 *
+	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
+	 * also support using this hook for enabling a CRTC to facilitate
+	 * transitions to atomic, but it is deprecated. Instead @atomic_enable
+	 * should be used.
+	 */
+	void (*commit)(struct drm_crtc *crtc);
+
+	/**
+	 * @mode_valid:
+	 *
+	 * This callback is used to check if a specific mode is valid in this
+	 * crtc. This should be implemented if the crtc has some sort of
+	 * restriction in the modes it can display. For example, a given crtc
+	 * may be responsible to set a clock value. If the clock can not
+	 * produce all the values for the available modes then this callback
+	 * can be used to restrict the number of modes to only the ones that
+	 * can be displayed.
+	 *
+	 * This hook is used by the probe helpers to filter the mode list in
+	 * drm_helper_probe_single_connector_modes(), and it is used by the
+	 * atomic helpers to validate modes supplied by userspace in
+	 * drm_atomic_helper_check_modeset().
+	 *
+	 * This function is optional.
+	 *
+	 * NOTE:
+	 *
+	 * Since this function is both called from the check phase of an atomic
+	 * commit, and the mode validation in the probe paths it is not allowed
+	 * to look at anything else but the passed-in mode, and validate it
+	 * against configuration-invariant hardware constraints. Any further
+	 * limits which depend upon the configuration can only be checked in
+	 * @mode_fixup or @atomic_check.
+	 *
+	 * RETURNS:
+	 *
+	 * drm_mode_status Enum
+	 */
+	enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc,
+					   const struct drm_display_mode *mode);
+
+	/**
+	 * @mode_fixup:
+	 *
+	 * This callback is used to validate a mode. The parameter mode is the
+	 * display mode that userspace requested, adjusted_mode is the mode the
+	 * encoders need to be fed with. Note that this is the inverse semantics
+	 * of the meaning for the &drm_encoder and &drm_bridge_funcs.mode_fixup
+	 * vfunc. If the CRTC cannot support the requested conversion from mode
+	 * to adjusted_mode it should reject the modeset. See also
+	 * &drm_crtc_state.adjusted_mode for more details.
+	 *
+	 * This function is used by both legacy CRTC helpers and atomic helpers.
+	 * With atomic helpers it is optional.
+	 *
+	 * NOTE:
+	 *
+	 * This function is called in the check phase of atomic modesets, which
+	 * can be aborted for any reason (including on userspace's request to
+	 * just check whether a configuration would be possible). Atomic drivers
+	 * MUST NOT touch any persistent state (hardware or software) or data
+	 * structures except the passed in adjusted_mode parameter.
+	 *
+	 * This is in contrast to the legacy CRTC helpers where this was
+	 * allowed.
+	 *
+	 * Atomic drivers which need to inspect and adjust more state should
+	 * instead use the @atomic_check callback, but note that they're not
+	 * perfectly equivalent: @mode_valid is called from
+	 * drm_atomic_helper_check_modeset(), but @atomic_check is called from
+	 * drm_atomic_helper_check_planes(), because originally it was meant for
+	 * plane update checks only.
+	 *
+	 * Also beware that userspace can request its own custom modes, neither
+	 * core nor helpers filter modes to the list of probe modes reported by
+	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
+	 * that modes are filtered consistently put any CRTC constraints and
+	 * limits checks into @mode_valid.
+	 *
+	 * RETURNS:
+	 *
+	 * True if an acceptable configuration is possible, false if the modeset
+	 * operation should be rejected.
+	 */
+	bool (*mode_fixup)(struct drm_crtc *crtc,
+			   const struct drm_display_mode *mode,
+			   struct drm_display_mode *adjusted_mode);
+
+	/**
+	 * @mode_set:
+	 *
+	 * This callback is used by the legacy CRTC helpers to set a new mode,
+	 * position and framebuffer. Since it ties the primary plane to every
+	 * mode change it is incompatible with universal plane support. And
+	 * since it can't update other planes it's incompatible with atomic
+	 * modeset support.
+	 *
+	 * This callback is only used by CRTC helpers and deprecated.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode,
+			struct drm_display_mode *adjusted_mode, int x, int y,
+			struct drm_framebuffer *old_fb);
+
+	/**
+	 * @mode_set_nofb:
+	 *
+	 * This callback is used to update the display mode of a CRTC without
+	 * changing anything of the primary plane configuration. This fits the
+	 * requirement of atomic and hence is used by the atomic helpers.
+	 *
+	 * Note that the display pipe is completely off when this function is
+	 * called. Atomic drivers which need hardware to be running before they
+	 * program the new display mode (e.g. because they implement runtime PM)
+	 * should not use this hook. This is because the helper library calls
+	 * this hook only once per mode change and not every time the display
+	 * pipeline is suspended using either DPMS or the new "ACTIVE" property.
+	 * Which means register values set in this callback might get reset when
+	 * the CRTC is suspended, but not restored.  Such drivers should instead
+	 * move all their CRTC setup into the @atomic_enable callback.
+	 *
+	 * This callback is optional.
+	 */
+	void (*mode_set_nofb)(struct drm_crtc *crtc);
+
+	/**
+	 * @mode_set_base:
+	 *
+	 * This callback is used by the legacy CRTC helpers to set a new
+	 * framebuffer and scanout position. It is optional and used as an
+	 * optimized fast-path instead of a full mode set operation with all the
+	 * resulting flickering. If it is not present
+	 * drm_crtc_helper_set_config() will fall back to a full modeset, using
+	 * the @mode_set callback. Since it can't update other planes it's
+	 * incompatible with atomic modeset support.
+	 *
+	 * This callback is only used by the CRTC helpers and deprecated.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*mode_set_base)(struct drm_crtc *crtc, int x, int y,
+			     struct drm_framebuffer *old_fb);
+
+	/**
+	 * @mode_set_base_atomic:
+	 *
+	 * This callback is used by the fbdev helpers to set a new framebuffer
+	 * and scanout without sleeping, i.e. from an atomic calling context. It
+	 * is only used to implement kgdb support.
+	 *
+	 * This callback is optional and only needed for kgdb support in the fbdev
+	 * helpers.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or a negative error code on failure.
+	 */
+	int (*mode_set_base_atomic)(struct drm_crtc *crtc,
+				    struct drm_framebuffer *fb, int x, int y,
+				    enum mode_set_atomic);
+
+	/**
+	 * @disable:
+	 *
+	 * This callback should be used to disable the CRTC. With the atomic
+	 * drivers it is called after all encoders connected to this CRTC have
+	 * been shut off already using their own
+	 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
+	 * simple drivers can just add their own hooks and call it from this
+	 * CRTC callback here by looping over all encoders connected to it using
+	 * for_each_encoder_on_crtc().
+	 *
+	 * This hook is used both by legacy CRTC helpers and atomic helpers.
+	 * Atomic drivers don't need to implement it if there's no need to
+	 * disable anything at the CRTC level. To ensure that runtime PM
+	 * handling (using either DPMS or the new "ACTIVE" property) works
+	 * @disable must be the inverse of @atomic_enable for atomic drivers.
+	 * Atomic drivers should consider to use @atomic_disable instead of
+	 * this one.
+	 *
+	 * NOTE:
+	 *
+	 * With legacy CRTC helpers there's a big semantic difference between
+	 * @disable and other hooks (like @prepare or @dpms) used to shut down a
+	 * CRTC: @disable is only called when also logically disabling the
+	 * display pipeline and needs to release any resources acquired in
+	 * @mode_set (like shared PLLs, or again release pinned framebuffers).
+	 *
+	 * Therefore @disable must be the inverse of @mode_set plus @commit for
+	 * drivers still using legacy CRTC helpers, which is different from the
+	 * rules under atomic.
+	 */
+	void (*disable)(struct drm_crtc *crtc);
+
+	/**
+	 * @atomic_check:
+	 *
+	 * Drivers should check plane-update related CRTC constraints in this
+	 * hook. They can also check mode related limitations but need to be
+	 * aware of the calling order, since this hook is used by
+	 * drm_atomic_helper_check_planes() whereas the preparations needed to
+	 * check output routing and the display mode is done in
+	 * drm_atomic_helper_check_modeset(). Therefore drivers that want to
+	 * check output routing and display mode constraints in this callback
+	 * must ensure that drm_atomic_helper_check_modeset() has been called
+	 * beforehand. This is calling order used by the default helper
+	 * implementation in drm_atomic_helper_check().
+	 *
+	 * When using drm_atomic_helper_check_planes() this hook is called
+	 * after the &drm_plane_helper_funcs.atomic_check hook for planes, which
+	 * allows drivers to assign shared resources requested by planes in this
+	 * callback here. For more complicated dependencies the driver can call
+	 * the provided check helpers multiple times until the computed state
+	 * has a final configuration and everything has been checked.
+	 *
+	 * This function is also allowed to inspect any other object's state and
+	 * can add more state objects to the atomic commit if needed. Care must
+	 * be taken though to ensure that state check and compute functions for
+	 * these added states are all called, and derived state in other objects
+	 * all updated. Again the recommendation is to just call check helpers
+	 * until a maximal configuration is reached.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is
+	 * optional.
+	 *
+	 * NOTE:
+	 *
+	 * This function is called in the check phase of an atomic update. The
+	 * driver is not allowed to change anything outside of the free-standing
+	 * state object passed-in.
+	 *
+	 * Also beware that userspace can request its own custom modes, neither
+	 * core nor helpers filter modes to the list of probe modes reported by
+	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
+	 * that modes are filtered consistently put any CRTC constraints and
+	 * limits checks into @mode_valid.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success, -EINVAL if the state or the transition can't be
+	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
+	 * attempt to obtain another state object ran into a &drm_modeset_lock
+	 * deadlock.
+	 */
+	int (*atomic_check)(struct drm_crtc *crtc,
+			    struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_begin:
+	 *
+	 * Drivers should prepare for an atomic update of multiple planes on
+	 * a CRTC in this hook. Depending upon hardware this might be vblank
+	 * evasion, blocking updates by setting bits or doing preparatory work
+	 * for e.g. manual update display.
+	 *
+	 * This hook is called before any plane commit functions are called.
+	 *
+	 * Note that the power state of the display pipe when this function is
+	 * called depends upon the exact helpers and calling sequence the driver
+	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
+	 * the tradeoffs and variants of plane commit helpers.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is
+	 * optional.
+	 */
+	void (*atomic_begin)(struct drm_crtc *crtc,
+			     struct drm_atomic_state *state);
+	/**
+	 * @atomic_flush:
+	 *
+	 * Drivers should finalize an atomic update of multiple planes on
+	 * a CRTC in this hook. Depending upon hardware this might include
+	 * checking that vblank evasion was successful, unblocking updates by
+	 * setting bits or setting the GO bit to flush out all updates.
+	 *
+	 * Simple hardware or hardware with special requirements can commit and
+	 * flush out all updates for all planes from this hook and forgo all the
+	 * other commit hooks for plane updates.
+	 *
+	 * This hook is called after any plane commit functions are called.
+	 *
+	 * Note that the power state of the display pipe when this function is
+	 * called depends upon the exact helpers and calling sequence the driver
+	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
+	 * the tradeoffs and variants of plane commit helpers.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is
+	 * optional.
+	 */
+	void (*atomic_flush)(struct drm_crtc *crtc,
+			     struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_enable:
+	 *
+	 * This callback should be used to enable the CRTC. With the atomic
+	 * drivers it is called before all encoders connected to this CRTC are
+	 * enabled through the encoder's own &drm_encoder_helper_funcs.enable
+	 * hook.  If that sequence is too simple drivers can just add their own
+	 * hooks and call it from this CRTC callback here by looping over all
+	 * encoders connected to it using for_each_encoder_on_crtc().
+	 *
+	 * This hook is used only by atomic helpers, for symmetry with
+	 * @atomic_disable. Atomic drivers don't need to implement it if there's
+	 * no need to enable anything at the CRTC level. To ensure that runtime
+	 * PM handling (using either DPMS or the new "ACTIVE" property) works
+	 * @atomic_enable must be the inverse of @atomic_disable for atomic
+	 * drivers.
+	 *
+	 * This function is optional.
+	 */
+	void (*atomic_enable)(struct drm_crtc *crtc,
+			      struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_disable:
+	 *
+	 * This callback should be used to disable the CRTC. With the atomic
+	 * drivers it is called after all encoders connected to this CRTC have
+	 * been shut off already using their own
+	 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
+	 * simple drivers can just add their own hooks and call it from this
+	 * CRTC callback here by looping over all encoders connected to it using
+	 * for_each_encoder_on_crtc().
+	 *
+	 * This hook is used only by atomic helpers. Atomic drivers don't
+	 * need to implement it if there's no need to disable anything at the
+	 * CRTC level.
+	 *
+	 * This function is optional.
+	 */
+	void (*atomic_disable)(struct drm_crtc *crtc,
+			       struct drm_atomic_state *state);
+
+	/**
+	 * @get_scanout_position:
+	 *
+	 * Called by vblank timestamping code.
+	 *
+	 * Returns the current display scanout position from a CRTC and an
+	 * optional accurate ktime_get() timestamp of when the position was
+	 * measured. Note that this is a helper callback which is only used
+	 * if a driver uses drm_crtc_vblank_helper_get_vblank_timestamp()
+	 * for the @drm_crtc_funcs.get_vblank_timestamp callback.
+	 *
+	 * Parameters:
+	 *
+	 * crtc:
+	 *     The CRTC.
+	 * in_vblank_irq:
+	 *     True when called from drm_crtc_handle_vblank(). Some drivers
+	 *     need to apply some workarounds for gpu-specific vblank irq
+	 *     quirks if the flag is set.
+	 * vpos:
+	 *     Target location for current vertical scanout position.
+	 * hpos:
+	 *     Target location for current horizontal scanout position.
+	 * stime:
+	 *     Target location for timestamp taken immediately before
+	 *     scanout position query. Can be NULL to skip timestamp.
+	 * etime:
+	 *     Target location for timestamp taken immediately after
+	 *     scanout position query. Can be NULL to skip timestamp.
+	 * mode:
+	 *     Current display timings.
+	 *
+	 * Returns vpos as a positive number while in active scanout area.
+	 * Returns vpos as a negative number inside vblank, counting the number
+	 * of scanlines to go until end of vblank, e.g., -1 means "one scanline
+	 * until start of active scanout / end of vblank."
+	 *
+	 * Returns:
+	 *
+	 * True on success, false if a reliable scanout position counter could
+	 * not be read out.
+	 */
+	bool (*get_scanout_position)(struct drm_crtc *crtc,
+				     bool in_vblank_irq, int *vpos, int *hpos,
+				     ktime_t *stime, ktime_t *etime,
+				     const struct drm_display_mode *mode);
+};
+
+/**
+ * drm_crtc_helper_add - sets the helper vtable for a crtc
+ * @crtc: DRM CRTC
+ * @funcs: helper vtable to set for @crtc
+ */
+static inline void drm_crtc_helper_add(struct drm_crtc *crtc,
+				       const struct drm_crtc_helper_funcs *funcs)
+{
+	crtc->helper_private = funcs;
+}
+
+#endif /* __DRM_CRTC_HELPER_VTABLE_H__ */
diff --git a/include/drm/drm_encoder_helper_vtable.h b/include/drm/drm_encoder_helper_vtable.h
new file mode 100644
index 0000000000000000..434de1ebb829f3ed
--- /dev/null
+++ b/include/drm/drm_encoder_helper_vtable.h
@@ -0,0 +1,381 @@
+/*
+ * Copyright © 2006 Keith Packard
+ * Copyright © 2007-2008 Dave Airlie
+ * Copyright © 2007-2008 Intel Corporation
+ *   Jesse Barnes <jesse.barnes@intel.com>
+ * Copyright © 2011-2013 Intel Corporation
+ * Copyright © 2015 Intel Corporation
+ *   Daniel Vetter <daniel.vetter@ffwll.ch>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __DRM_ENCODER_HELPER_VTABLE_H__
+#define __DRM_ENCODER_HELPER_VTABLE_H__
+
+/**
+ * struct drm_encoder_helper_funcs - helper operations for encoders
+ *
+ * These hooks are used by the legacy CRTC helpers and the new atomic
+ * modesetting helpers.
+ */
+struct drm_encoder_helper_funcs {
+	/**
+	 * @dpms:
+	 *
+	 * Callback to control power levels on the encoder.  If the mode passed in
+	 * is unsupported, the provider must use the next lowest power level.
+	 * This is used by the legacy encoder helpers to implement DPMS
+	 * functionality in drm_helper_connector_dpms().
+	 *
+	 * This callback is also used to disable an encoder by calling it with
+	 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
+	 *
+	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
+	 * also support using this hook for enabling and disabling an encoder to
+	 * facilitate transitions to atomic, but it is deprecated. Instead
+	 * @enable and @disable should be used.
+	 */
+	void (*dpms)(struct drm_encoder *encoder, int mode);
+
+	/**
+	 * @mode_valid:
+	 *
+	 * This callback is used to check if a specific mode is valid in this
+	 * encoder. This should be implemented if the encoder has some sort
+	 * of restriction in the modes it can display. For example, a given
+	 * encoder may be responsible to set a clock value. If the clock can
+	 * not produce all the values for the available modes then this callback
+	 * can be used to restrict the number of modes to only the ones that
+	 * can be displayed.
+	 *
+	 * This hook is used by the probe helpers to filter the mode list in
+	 * drm_helper_probe_single_connector_modes(), and it is used by the
+	 * atomic helpers to validate modes supplied by userspace in
+	 * drm_atomic_helper_check_modeset().
+	 *
+	 * This function is optional.
+	 *
+	 * NOTE:
+	 *
+	 * Since this function is both called from the check phase of an atomic
+	 * commit, and the mode validation in the probe paths it is not allowed
+	 * to look at anything else but the passed-in mode, and validate it
+	 * against configuration-invariant hardware constraints. Any further
+	 * limits which depend upon the configuration can only be checked in
+	 * @mode_fixup or @atomic_check.
+	 *
+	 * RETURNS:
+	 *
+	 * drm_mode_status Enum
+	 */
+	enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc,
+					   const struct drm_display_mode *mode);
+
+	/**
+	 * @mode_fixup:
+	 *
+	 * This callback is used to validate and adjust a mode. The parameter
+	 * mode is the display mode that should be fed to the next element in
+	 * the display chain, either the final &drm_connector or a &drm_bridge.
+	 * The parameter adjusted_mode is the input mode the encoder requires. It
+	 * can be modified by this callback and does not need to match mode. See
+	 * also &drm_crtc_state.adjusted_mode for more details.
+	 *
+	 * This function is used by both legacy CRTC helpers and atomic helpers.
+	 * This hook is optional.
+	 *
+	 * NOTE:
+	 *
+	 * This function is called in the check phase of atomic modesets, which
+	 * can be aborted for any reason (including on userspace's request to
+	 * just check whether a configuration would be possible). Atomic drivers
+	 * MUST NOT touch any persistent state (hardware or software) or data
+	 * structures except the passed in adjusted_mode parameter.
+	 *
+	 * This is in contrast to the legacy CRTC helpers where this was
+	 * allowed.
+	 *
+	 * Atomic drivers which need to inspect and adjust more state should
+	 * instead use the @atomic_check callback. If @atomic_check is used,
+	 * this hook isn't called since @atomic_check allows a strict superset
+	 * of the functionality of @mode_fixup.
+	 *
+	 * Also beware that userspace can request its own custom modes, neither
+	 * core nor helpers filter modes to the list of probe modes reported by
+	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
+	 * that modes are filtered consistently put any encoder constraints and
+	 * limits checks into @mode_valid.
+	 *
+	 * RETURNS:
+	 *
+	 * True if an acceptable configuration is possible, false if the modeset
+	 * operation should be rejected.
+	 */
+	bool (*mode_fixup)(struct drm_encoder *encoder,
+			   const struct drm_display_mode *mode,
+			   struct drm_display_mode *adjusted_mode);
+
+	/**
+	 * @prepare:
+	 *
+	 * This callback should prepare the encoder for a subsequent modeset,
+	 * which in practice means the driver should disable the encoder if it
+	 * is running. Most drivers ended up implementing this by calling their
+	 * @dpms hook with DRM_MODE_DPMS_OFF.
+	 *
+	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
+	 * also support using this hook for disabling an encoder to facilitate
+	 * transitions to atomic, but it is deprecated. Instead @disable should
+	 * be used.
+	 */
+	void (*prepare)(struct drm_encoder *encoder);
+
+	/**
+	 * @commit:
+	 *
+	 * This callback should commit the new mode on the encoder after a modeset,
+	 * which in practice means the driver should enable the encoder.  Most
+	 * drivers ended up implementing this by calling their @dpms hook with
+	 * DRM_MODE_DPMS_ON.
+	 *
+	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
+	 * also support using this hook for enabling an encoder to facilitate
+	 * transitions to atomic, but it is deprecated. Instead @enable should
+	 * be used.
+	 */
+	void (*commit)(struct drm_encoder *encoder);
+
+	/**
+	 * @mode_set:
+	 *
+	 * This callback is used to update the display mode of an encoder.
+	 *
+	 * Note that the display pipe is completely off when this function is
+	 * called. Drivers which need hardware to be running before they program
+	 * the new display mode (because they implement runtime PM) should not
+	 * use this hook, because the helper library calls it only once and not
+	 * every time the display pipeline is suspend using either DPMS or the
+	 * new "ACTIVE" property. Such drivers should instead move all their
+	 * encoder setup into the @enable callback.
+	 *
+	 * This callback is used both by the legacy CRTC helpers and the atomic
+	 * modeset helpers. It is optional in the atomic helpers.
+	 *
+	 * NOTE:
+	 *
+	 * If the driver uses the atomic modeset helpers and needs to inspect
+	 * the connector state or connector display info during mode setting,
+	 * @atomic_mode_set can be used instead.
+	 */
+	void (*mode_set)(struct drm_encoder *encoder,
+			 struct drm_display_mode *mode,
+			 struct drm_display_mode *adjusted_mode);
+
+	/**
+	 * @atomic_mode_set:
+	 *
+	 * This callback is used to update the display mode of an encoder.
+	 *
+	 * Note that the display pipe is completely off when this function is
+	 * called. Drivers which need hardware to be running before they program
+	 * the new display mode (because they implement runtime PM) should not
+	 * use this hook, because the helper library calls it only once and not
+	 * every time the display pipeline is suspended using either DPMS or the
+	 * new "ACTIVE" property. Such drivers should instead move all their
+	 * encoder setup into the @enable callback.
+	 *
+	 * This callback is used by the atomic modeset helpers in place of the
+	 * @mode_set callback, if set by the driver. It is optional and should
+	 * be used instead of @mode_set if the driver needs to inspect the
+	 * connector state or display info, since there is no direct way to
+	 * go from the encoder to the current connector.
+	 */
+	void (*atomic_mode_set)(struct drm_encoder *encoder,
+				struct drm_crtc_state *crtc_state,
+				struct drm_connector_state *conn_state);
+
+	/**
+	 * @detect:
+	 *
+	 * This callback can be used by drivers who want to do detection on the
+	 * encoder object instead of in connector functions.
+	 *
+	 * It is not used by any helper and therefore has purely driver-specific
+	 * semantics. New drivers shouldn't use this and instead just implement
+	 * their own private callbacks.
+	 *
+	 * FIXME:
+	 *
+	 * This should just be converted into a pile of driver vfuncs.
+	 * Currently radeon, amdgpu and nouveau are using it.
+	 */
+	enum drm_connector_status (*detect)(struct drm_encoder *encoder,
+					    struct drm_connector *connector);
+
+	/**
+	 * @atomic_disable:
+	 *
+	 * This callback should be used to disable the encoder. With the atomic
+	 * drivers it is called before this encoder's CRTC has been shut off
+	 * using their own &drm_crtc_helper_funcs.atomic_disable hook. If that
+	 * sequence is too simple drivers can just add their own driver private
+	 * encoder hooks and call them from CRTC's callback by looping over all
+	 * encoders connected to it using for_each_encoder_on_crtc().
+	 *
+	 * This callback is a variant of @disable that provides the atomic state
+	 * to the driver. If @atomic_disable is implemented, @disable is not
+	 * called by the helpers.
+	 *
+	 * This hook is only used by atomic helpers. Atomic drivers don't need
+	 * to implement it if there's no need to disable anything at the encoder
+	 * level. To ensure that runtime PM handling (using either DPMS or the
+	 * new "ACTIVE" property) works @atomic_disable must be the inverse of
+	 * @atomic_enable.
+	 */
+	void (*atomic_disable)(struct drm_encoder *encoder,
+			       struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_enable:
+	 *
+	 * This callback should be used to enable the encoder. It is called
+	 * after this encoder's CRTC has been enabled using their own
+	 * &drm_crtc_helper_funcs.atomic_enable hook. If that sequence is
+	 * too simple drivers can just add their own driver private encoder
+	 * hooks and call them from CRTC's callback by looping over all encoders
+	 * connected to it using for_each_encoder_on_crtc().
+	 *
+	 * This callback is a variant of @enable that provides the atomic state
+	 * to the driver. If @atomic_enable is implemented, @enable is not
+	 * called by the helpers.
+	 *
+	 * This hook is only used by atomic helpers, it is the opposite of
+	 * @atomic_disable. Atomic drivers don't need to implement it if there's
+	 * no need to enable anything at the encoder level. To ensure that
+	 * runtime PM handling works @atomic_enable must be the inverse of
+	 * @atomic_disable.
+	 */
+	void (*atomic_enable)(struct drm_encoder *encoder,
+			      struct drm_atomic_state *state);
+
+	/**
+	 * @disable:
+	 *
+	 * This callback should be used to disable the encoder. With the atomic
+	 * drivers it is called before this encoder's CRTC has been shut off
+	 * using their own &drm_crtc_helper_funcs.disable hook.  If that
+	 * sequence is too simple drivers can just add their own driver private
+	 * encoder hooks and call them from CRTC's callback by looping over all
+	 * encoders connected to it using for_each_encoder_on_crtc().
+	 *
+	 * This hook is used both by legacy CRTC helpers and atomic helpers.
+	 * Atomic drivers don't need to implement it if there's no need to
+	 * disable anything at the encoder level. To ensure that runtime PM
+	 * handling (using either DPMS or the new "ACTIVE" property) works
+	 * @disable must be the inverse of @enable for atomic drivers.
+	 *
+	 * For atomic drivers also consider @atomic_disable and save yourself
+	 * from having to read the NOTE below!
+	 *
+	 * NOTE:
+	 *
+	 * With legacy CRTC helpers there's a big semantic difference between
+	 * @disable and other hooks (like @prepare or @dpms) used to shut down a
+	 * encoder: @disable is only called when also logically disabling the
+	 * display pipeline and needs to release any resources acquired in
+	 * @mode_set (like shared PLLs, or again release pinned framebuffers).
+	 *
+	 * Therefore @disable must be the inverse of @mode_set plus @commit for
+	 * drivers still using legacy CRTC helpers, which is different from the
+	 * rules under atomic.
+	 */
+	void (*disable)(struct drm_encoder *encoder);
+
+	/**
+	 * @enable:
+	 *
+	 * This callback should be used to enable the encoder. With the atomic
+	 * drivers it is called after this encoder's CRTC has been enabled using
+	 * their own &drm_crtc_helper_funcs.enable hook.  If that sequence is
+	 * too simple drivers can just add their own driver private encoder
+	 * hooks and call them from CRTC's callback by looping over all encoders
+	 * connected to it using for_each_encoder_on_crtc().
+	 *
+	 * This hook is only used by atomic helpers, it is the opposite of
+	 * @disable. Atomic drivers don't need to implement it if there's no
+	 * need to enable anything at the encoder level. To ensure that
+	 * runtime PM handling (using either DPMS or the new "ACTIVE" property)
+	 * works @enable must be the inverse of @disable for atomic drivers.
+	 */
+	void (*enable)(struct drm_encoder *encoder);
+
+	/**
+	 * @atomic_check:
+	 *
+	 * This callback is used to validate encoder state for atomic drivers.
+	 * Since the encoder is the object connecting the CRTC and connector it
+	 * gets passed both states, to be able to validate interactions and
+	 * update the CRTC to match what the encoder needs for the requested
+	 * connector.
+	 *
+	 * Since this provides a strict superset of the functionality of
+	 * @mode_fixup (the requested and adjusted modes are both available
+	 * through the passed in &struct drm_crtc_state) @mode_fixup is not
+	 * called when @atomic_check is implemented.
+	 *
+	 * This function is used by the atomic helpers, but it is optional.
+	 *
+	 * NOTE:
+	 *
+	 * This function is called in the check phase of an atomic update. The
+	 * driver is not allowed to change anything outside of the free-standing
+	 * state objects passed-in or assembled in the overall &drm_atomic_state
+	 * update tracking structure.
+	 *
+	 * Also beware that userspace can request its own custom modes, neither
+	 * core nor helpers filter modes to the list of probe modes reported by
+	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
+	 * that modes are filtered consistently put any encoder constraints and
+	 * limits checks into @mode_valid.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success, -EINVAL if the state or the transition can't be
+	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
+	 * attempt to obtain another state object ran into a &drm_modeset_lock
+	 * deadlock.
+	 */
+	int (*atomic_check)(struct drm_encoder *encoder,
+			    struct drm_crtc_state *crtc_state,
+			    struct drm_connector_state *conn_state);
+};
+
+/**
+ * drm_encoder_helper_add - sets the helper vtable for an encoder
+ * @encoder: DRM encoder
+ * @funcs: helper vtable to set for @encoder
+ */
+static inline void drm_encoder_helper_add(struct drm_encoder *encoder,
+					  const struct drm_encoder_helper_funcs *funcs)
+{
+	encoder->helper_private = funcs;
+}
+
+#endif /* __DRM_ENCODER_HELPER_VTABLE_H__ */
diff --git a/include/drm/drm_mode_config_helper_vtable.h b/include/drm/drm_mode_config_helper_vtable.h
new file mode 100644
index 0000000000000000..a56e3490e27411de
--- /dev/null
+++ b/include/drm/drm_mode_config_helper_vtable.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright © 2006 Keith Packard
+ * Copyright © 2007-2008 Dave Airlie
+ * Copyright © 2007-2008 Intel Corporation
+ *   Jesse Barnes <jesse.barnes@intel.com>
+ * Copyright © 2011-2013 Intel Corporation
+ * Copyright © 2015 Intel Corporation
+ *   Daniel Vetter <daniel.vetter@ffwll.ch>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __DRM_MODE_CONFIG_HELPER_VTABLE_H__
+#define __DRM_MODE_CONFIG_HELPER_VTABLE_H__
+
+/**
+ * struct drm_mode_config_helper_funcs - global modeset helper operations
+ *
+ * These helper functions are used by the atomic helpers.
+ */
+struct drm_mode_config_helper_funcs {
+	/**
+	 * @atomic_commit_tail:
+	 *
+	 * This hook is used by the default atomic_commit() hook implemented in
+	 * drm_atomic_helper_commit() together with the nonblocking commit
+	 * helpers (see drm_atomic_helper_setup_commit() for a starting point)
+	 * to implement blocking and nonblocking commits easily. It is not used
+	 * by the atomic helpers
+	 *
+	 * This function is called when the new atomic state has already been
+	 * swapped into the various state pointers. The passed in state
+	 * therefore contains copies of the old/previous state. This hook should
+	 * commit the new state into hardware. Note that the helpers have
+	 * already waited for preceding atomic commits and fences, but drivers
+	 * can add more waiting calls at the start of their implementation, e.g.
+	 * to wait for driver-internal request for implicit syncing, before
+	 * starting to commit the update to the hardware.
+	 *
+	 * After the atomic update is committed to the hardware this hook needs
+	 * to call drm_atomic_helper_commit_hw_done(). Then wait for the update
+	 * to be executed by the hardware, for example using
+	 * drm_atomic_helper_wait_for_vblanks() or
+	 * drm_atomic_helper_wait_for_flip_done(), and then clean up the old
+	 * framebuffers using drm_atomic_helper_cleanup_planes().
+	 *
+	 * When disabling a CRTC this hook _must_ stall for the commit to
+	 * complete. Vblank waits don't work on disabled CRTC, hence the core
+	 * can't take care of this. And it also can't rely on the vblank event,
+	 * since that can be signalled already when the screen shows black,
+	 * which can happen much earlier than the last hardware access needed to
+	 * shut off the display pipeline completely.
+	 *
+	 * This hook is optional, the default implementation is
+	 * drm_atomic_helper_commit_tail().
+	 */
+	void (*atomic_commit_tail)(struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_commit_setup:
+	 *
+	 * This hook is used by the default atomic_commit() hook implemented in
+	 * drm_atomic_helper_commit() together with the nonblocking helpers (see
+	 * drm_atomic_helper_setup_commit()) to extend the DRM commit setup. It
+	 * is not used by the atomic helpers.
+	 *
+	 * This function is called at the end of
+	 * drm_atomic_helper_setup_commit(), so once the commit has been
+	 * properly setup across the generic DRM object states. It allows
+	 * drivers to do some additional commit tracking that isn't related to a
+	 * CRTC, plane or connector, tracked in a &drm_private_obj structure.
+	 *
+	 * Note that the documentation of &drm_private_obj has more details on
+	 * how one should implement this.
+	 *
+	 * This hook is optional.
+	 */
+	int (*atomic_commit_setup)(struct drm_atomic_state *state);
+};
+
+#endif /* __DRM_MODE_CONFIG_HELPER_VTABLE_H__ */
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index 91860372be6c064e..a9fb43b07b60872d 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -48,1466 +48,10 @@
  * To make this clear all the helper vtables are pulled together in this location here.
  */
 
-struct drm_writeback_connector;
-struct drm_writeback_job;
-
-enum mode_set_atomic {
-	LEAVE_ATOMIC_MODE_SET,
-	ENTER_ATOMIC_MODE_SET,
-};
-
-/**
- * struct drm_crtc_helper_funcs - helper operations for CRTCs
- *
- * These hooks are used by the legacy CRTC helpers and the new atomic
- * modesetting helpers.
- */
-struct drm_crtc_helper_funcs {
-	/**
-	 * @dpms:
-	 *
-	 * Callback to control power levels on the CRTC.  If the mode passed in
-	 * is unsupported, the provider must use the next lowest power level.
-	 * This is used by the legacy CRTC helpers to implement DPMS
-	 * functionality in drm_helper_connector_dpms().
-	 *
-	 * This callback is also used to disable a CRTC by calling it with
-	 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
-	 *
-	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
-	 * also support using this hook for enabling and disabling a CRTC to
-	 * facilitate transitions to atomic, but it is deprecated. Instead
-	 * @atomic_enable and @atomic_disable should be used.
-	 */
-	void (*dpms)(struct drm_crtc *crtc, int mode);
-
-	/**
-	 * @prepare:
-	 *
-	 * This callback should prepare the CRTC for a subsequent modeset, which
-	 * in practice means the driver should disable the CRTC if it is
-	 * running. Most drivers ended up implementing this by calling their
-	 * @dpms hook with DRM_MODE_DPMS_OFF.
-	 *
-	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
-	 * also support using this hook for disabling a CRTC to facilitate
-	 * transitions to atomic, but it is deprecated. Instead @atomic_disable
-	 * should be used.
-	 */
-	void (*prepare)(struct drm_crtc *crtc);
-
-	/**
-	 * @commit:
-	 *
-	 * This callback should commit the new mode on the CRTC after a modeset,
-	 * which in practice means the driver should enable the CRTC.  Most
-	 * drivers ended up implementing this by calling their @dpms hook with
-	 * DRM_MODE_DPMS_ON.
-	 *
-	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
-	 * also support using this hook for enabling a CRTC to facilitate
-	 * transitions to atomic, but it is deprecated. Instead @atomic_enable
-	 * should be used.
-	 */
-	void (*commit)(struct drm_crtc *crtc);
-
-	/**
-	 * @mode_valid:
-	 *
-	 * This callback is used to check if a specific mode is valid in this
-	 * crtc. This should be implemented if the crtc has some sort of
-	 * restriction in the modes it can display. For example, a given crtc
-	 * may be responsible to set a clock value. If the clock can not
-	 * produce all the values for the available modes then this callback
-	 * can be used to restrict the number of modes to only the ones that
-	 * can be displayed.
-	 *
-	 * This hook is used by the probe helpers to filter the mode list in
-	 * drm_helper_probe_single_connector_modes(), and it is used by the
-	 * atomic helpers to validate modes supplied by userspace in
-	 * drm_atomic_helper_check_modeset().
-	 *
-	 * This function is optional.
-	 *
-	 * NOTE:
-	 *
-	 * Since this function is both called from the check phase of an atomic
-	 * commit, and the mode validation in the probe paths it is not allowed
-	 * to look at anything else but the passed-in mode, and validate it
-	 * against configuration-invariant hardware constraints. Any further
-	 * limits which depend upon the configuration can only be checked in
-	 * @mode_fixup or @atomic_check.
-	 *
-	 * RETURNS:
-	 *
-	 * drm_mode_status Enum
-	 */
-	enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc,
-					   const struct drm_display_mode *mode);
-
-	/**
-	 * @mode_fixup:
-	 *
-	 * This callback is used to validate a mode. The parameter mode is the
-	 * display mode that userspace requested, adjusted_mode is the mode the
-	 * encoders need to be fed with. Note that this is the inverse semantics
-	 * of the meaning for the &drm_encoder and &drm_bridge_funcs.mode_fixup
-	 * vfunc. If the CRTC cannot support the requested conversion from mode
-	 * to adjusted_mode it should reject the modeset. See also
-	 * &drm_crtc_state.adjusted_mode for more details.
-	 *
-	 * This function is used by both legacy CRTC helpers and atomic helpers.
-	 * With atomic helpers it is optional.
-	 *
-	 * NOTE:
-	 *
-	 * This function is called in the check phase of atomic modesets, which
-	 * can be aborted for any reason (including on userspace's request to
-	 * just check whether a configuration would be possible). Atomic drivers
-	 * MUST NOT touch any persistent state (hardware or software) or data
-	 * structures except the passed in adjusted_mode parameter.
-	 *
-	 * This is in contrast to the legacy CRTC helpers where this was
-	 * allowed.
-	 *
-	 * Atomic drivers which need to inspect and adjust more state should
-	 * instead use the @atomic_check callback, but note that they're not
-	 * perfectly equivalent: @mode_valid is called from
-	 * drm_atomic_helper_check_modeset(), but @atomic_check is called from
-	 * drm_atomic_helper_check_planes(), because originally it was meant for
-	 * plane update checks only.
-	 *
-	 * Also beware that userspace can request its own custom modes, neither
-	 * core nor helpers filter modes to the list of probe modes reported by
-	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
-	 * that modes are filtered consistently put any CRTC constraints and
-	 * limits checks into @mode_valid.
-	 *
-	 * RETURNS:
-	 *
-	 * True if an acceptable configuration is possible, false if the modeset
-	 * operation should be rejected.
-	 */
-	bool (*mode_fixup)(struct drm_crtc *crtc,
-			   const struct drm_display_mode *mode,
-			   struct drm_display_mode *adjusted_mode);
-
-	/**
-	 * @mode_set:
-	 *
-	 * This callback is used by the legacy CRTC helpers to set a new mode,
-	 * position and framebuffer. Since it ties the primary plane to every
-	 * mode change it is incompatible with universal plane support. And
-	 * since it can't update other planes it's incompatible with atomic
-	 * modeset support.
-	 *
-	 * This callback is only used by CRTC helpers and deprecated.
-	 *
-	 * RETURNS:
-	 *
-	 * 0 on success or a negative error code on failure.
-	 */
-	int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode,
-			struct drm_display_mode *adjusted_mode, int x, int y,
-			struct drm_framebuffer *old_fb);
-
-	/**
-	 * @mode_set_nofb:
-	 *
-	 * This callback is used to update the display mode of a CRTC without
-	 * changing anything of the primary plane configuration. This fits the
-	 * requirement of atomic and hence is used by the atomic helpers.
-	 *
-	 * Note that the display pipe is completely off when this function is
-	 * called. Atomic drivers which need hardware to be running before they
-	 * program the new display mode (e.g. because they implement runtime PM)
-	 * should not use this hook. This is because the helper library calls
-	 * this hook only once per mode change and not every time the display
-	 * pipeline is suspended using either DPMS or the new "ACTIVE" property.
-	 * Which means register values set in this callback might get reset when
-	 * the CRTC is suspended, but not restored.  Such drivers should instead
-	 * move all their CRTC setup into the @atomic_enable callback.
-	 *
-	 * This callback is optional.
-	 */
-	void (*mode_set_nofb)(struct drm_crtc *crtc);
-
-	/**
-	 * @mode_set_base:
-	 *
-	 * This callback is used by the legacy CRTC helpers to set a new
-	 * framebuffer and scanout position. It is optional and used as an
-	 * optimized fast-path instead of a full mode set operation with all the
-	 * resulting flickering. If it is not present
-	 * drm_crtc_helper_set_config() will fall back to a full modeset, using
-	 * the @mode_set callback. Since it can't update other planes it's
-	 * incompatible with atomic modeset support.
-	 *
-	 * This callback is only used by the CRTC helpers and deprecated.
-	 *
-	 * RETURNS:
-	 *
-	 * 0 on success or a negative error code on failure.
-	 */
-	int (*mode_set_base)(struct drm_crtc *crtc, int x, int y,
-			     struct drm_framebuffer *old_fb);
-
-	/**
-	 * @mode_set_base_atomic:
-	 *
-	 * This callback is used by the fbdev helpers to set a new framebuffer
-	 * and scanout without sleeping, i.e. from an atomic calling context. It
-	 * is only used to implement kgdb support.
-	 *
-	 * This callback is optional and only needed for kgdb support in the fbdev
-	 * helpers.
-	 *
-	 * RETURNS:
-	 *
-	 * 0 on success or a negative error code on failure.
-	 */
-	int (*mode_set_base_atomic)(struct drm_crtc *crtc,
-				    struct drm_framebuffer *fb, int x, int y,
-				    enum mode_set_atomic);
-
-	/**
-	 * @disable:
-	 *
-	 * This callback should be used to disable the CRTC. With the atomic
-	 * drivers it is called after all encoders connected to this CRTC have
-	 * been shut off already using their own
-	 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
-	 * simple drivers can just add their own hooks and call it from this
-	 * CRTC callback here by looping over all encoders connected to it using
-	 * for_each_encoder_on_crtc().
-	 *
-	 * This hook is used both by legacy CRTC helpers and atomic helpers.
-	 * Atomic drivers don't need to implement it if there's no need to
-	 * disable anything at the CRTC level. To ensure that runtime PM
-	 * handling (using either DPMS or the new "ACTIVE" property) works
-	 * @disable must be the inverse of @atomic_enable for atomic drivers.
-	 * Atomic drivers should consider to use @atomic_disable instead of
-	 * this one.
-	 *
-	 * NOTE:
-	 *
-	 * With legacy CRTC helpers there's a big semantic difference between
-	 * @disable and other hooks (like @prepare or @dpms) used to shut down a
-	 * CRTC: @disable is only called when also logically disabling the
-	 * display pipeline and needs to release any resources acquired in
-	 * @mode_set (like shared PLLs, or again release pinned framebuffers).
-	 *
-	 * Therefore @disable must be the inverse of @mode_set plus @commit for
-	 * drivers still using legacy CRTC helpers, which is different from the
-	 * rules under atomic.
-	 */
-	void (*disable)(struct drm_crtc *crtc);
-
-	/**
-	 * @atomic_check:
-	 *
-	 * Drivers should check plane-update related CRTC constraints in this
-	 * hook. They can also check mode related limitations but need to be
-	 * aware of the calling order, since this hook is used by
-	 * drm_atomic_helper_check_planes() whereas the preparations needed to
-	 * check output routing and the display mode is done in
-	 * drm_atomic_helper_check_modeset(). Therefore drivers that want to
-	 * check output routing and display mode constraints in this callback
-	 * must ensure that drm_atomic_helper_check_modeset() has been called
-	 * beforehand. This is calling order used by the default helper
-	 * implementation in drm_atomic_helper_check().
-	 *
-	 * When using drm_atomic_helper_check_planes() this hook is called
-	 * after the &drm_plane_helper_funcs.atomic_check hook for planes, which
-	 * allows drivers to assign shared resources requested by planes in this
-	 * callback here. For more complicated dependencies the driver can call
-	 * the provided check helpers multiple times until the computed state
-	 * has a final configuration and everything has been checked.
-	 *
-	 * This function is also allowed to inspect any other object's state and
-	 * can add more state objects to the atomic commit if needed. Care must
-	 * be taken though to ensure that state check and compute functions for
-	 * these added states are all called, and derived state in other objects
-	 * all updated. Again the recommendation is to just call check helpers
-	 * until a maximal configuration is reached.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is
-	 * optional.
-	 *
-	 * NOTE:
-	 *
-	 * This function is called in the check phase of an atomic update. The
-	 * driver is not allowed to change anything outside of the free-standing
-	 * state object passed-in.
-	 *
-	 * Also beware that userspace can request its own custom modes, neither
-	 * core nor helpers filter modes to the list of probe modes reported by
-	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
-	 * that modes are filtered consistently put any CRTC constraints and
-	 * limits checks into @mode_valid.
-	 *
-	 * RETURNS:
-	 *
-	 * 0 on success, -EINVAL if the state or the transition can't be
-	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
-	 * attempt to obtain another state object ran into a &drm_modeset_lock
-	 * deadlock.
-	 */
-	int (*atomic_check)(struct drm_crtc *crtc,
-			    struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_begin:
-	 *
-	 * Drivers should prepare for an atomic update of multiple planes on
-	 * a CRTC in this hook. Depending upon hardware this might be vblank
-	 * evasion, blocking updates by setting bits or doing preparatory work
-	 * for e.g. manual update display.
-	 *
-	 * This hook is called before any plane commit functions are called.
-	 *
-	 * Note that the power state of the display pipe when this function is
-	 * called depends upon the exact helpers and calling sequence the driver
-	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
-	 * the tradeoffs and variants of plane commit helpers.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is
-	 * optional.
-	 */
-	void (*atomic_begin)(struct drm_crtc *crtc,
-			     struct drm_atomic_state *state);
-	/**
-	 * @atomic_flush:
-	 *
-	 * Drivers should finalize an atomic update of multiple planes on
-	 * a CRTC in this hook. Depending upon hardware this might include
-	 * checking that vblank evasion was successful, unblocking updates by
-	 * setting bits or setting the GO bit to flush out all updates.
-	 *
-	 * Simple hardware or hardware with special requirements can commit and
-	 * flush out all updates for all planes from this hook and forgo all the
-	 * other commit hooks for plane updates.
-	 *
-	 * This hook is called after any plane commit functions are called.
-	 *
-	 * Note that the power state of the display pipe when this function is
-	 * called depends upon the exact helpers and calling sequence the driver
-	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
-	 * the tradeoffs and variants of plane commit helpers.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is
-	 * optional.
-	 */
-	void (*atomic_flush)(struct drm_crtc *crtc,
-			     struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_enable:
-	 *
-	 * This callback should be used to enable the CRTC. With the atomic
-	 * drivers it is called before all encoders connected to this CRTC are
-	 * enabled through the encoder's own &drm_encoder_helper_funcs.enable
-	 * hook.  If that sequence is too simple drivers can just add their own
-	 * hooks and call it from this CRTC callback here by looping over all
-	 * encoders connected to it using for_each_encoder_on_crtc().
-	 *
-	 * This hook is used only by atomic helpers, for symmetry with
-	 * @atomic_disable. Atomic drivers don't need to implement it if there's
-	 * no need to enable anything at the CRTC level. To ensure that runtime
-	 * PM handling (using either DPMS or the new "ACTIVE" property) works
-	 * @atomic_enable must be the inverse of @atomic_disable for atomic
-	 * drivers.
-	 *
-	 * This function is optional.
-	 */
-	void (*atomic_enable)(struct drm_crtc *crtc,
-			      struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_disable:
-	 *
-	 * This callback should be used to disable the CRTC. With the atomic
-	 * drivers it is called after all encoders connected to this CRTC have
-	 * been shut off already using their own
-	 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
-	 * simple drivers can just add their own hooks and call it from this
-	 * CRTC callback here by looping over all encoders connected to it using
-	 * for_each_encoder_on_crtc().
-	 *
-	 * This hook is used only by atomic helpers. Atomic drivers don't
-	 * need to implement it if there's no need to disable anything at the
-	 * CRTC level.
-	 *
-	 * This function is optional.
-	 */
-	void (*atomic_disable)(struct drm_crtc *crtc,
-			       struct drm_atomic_state *state);
-
-	/**
-	 * @get_scanout_position:
-	 *
-	 * Called by vblank timestamping code.
-	 *
-	 * Returns the current display scanout position from a CRTC and an
-	 * optional accurate ktime_get() timestamp of when the position was
-	 * measured. Note that this is a helper callback which is only used
-	 * if a driver uses drm_crtc_vblank_helper_get_vblank_timestamp()
-	 * for the @drm_crtc_funcs.get_vblank_timestamp callback.
-	 *
-	 * Parameters:
-	 *
-	 * crtc:
-	 *     The CRTC.
-	 * in_vblank_irq:
-	 *     True when called from drm_crtc_handle_vblank(). Some drivers
-	 *     need to apply some workarounds for gpu-specific vblank irq
-	 *     quirks if the flag is set.
-	 * vpos:
-	 *     Target location for current vertical scanout position.
-	 * hpos:
-	 *     Target location for current horizontal scanout position.
-	 * stime:
-	 *     Target location for timestamp taken immediately before
-	 *     scanout position query. Can be NULL to skip timestamp.
-	 * etime:
-	 *     Target location for timestamp taken immediately after
-	 *     scanout position query. Can be NULL to skip timestamp.
-	 * mode:
-	 *     Current display timings.
-	 *
-	 * Returns vpos as a positive number while in active scanout area.
-	 * Returns vpos as a negative number inside vblank, counting the number
-	 * of scanlines to go until end of vblank, e.g., -1 means "one scanline
-	 * until start of active scanout / end of vblank."
-	 *
-	 * Returns:
-	 *
-	 * True on success, false if a reliable scanout position counter could
-	 * not be read out.
-	 */
-	bool (*get_scanout_position)(struct drm_crtc *crtc,
-				     bool in_vblank_irq, int *vpos, int *hpos,
-				     ktime_t *stime, ktime_t *etime,
-				     const struct drm_display_mode *mode);
-};
-
-/**
- * drm_crtc_helper_add - sets the helper vtable for a crtc
- * @crtc: DRM CRTC
- * @funcs: helper vtable to set for @crtc
- */
-static inline void drm_crtc_helper_add(struct drm_crtc *crtc,
-				       const struct drm_crtc_helper_funcs *funcs)
-{
-	crtc->helper_private = funcs;
-}
-
-/**
- * struct drm_encoder_helper_funcs - helper operations for encoders
- *
- * These hooks are used by the legacy CRTC helpers and the new atomic
- * modesetting helpers.
- */
-struct drm_encoder_helper_funcs {
-	/**
-	 * @dpms:
-	 *
-	 * Callback to control power levels on the encoder.  If the mode passed in
-	 * is unsupported, the provider must use the next lowest power level.
-	 * This is used by the legacy encoder helpers to implement DPMS
-	 * functionality in drm_helper_connector_dpms().
-	 *
-	 * This callback is also used to disable an encoder by calling it with
-	 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
-	 *
-	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
-	 * also support using this hook for enabling and disabling an encoder to
-	 * facilitate transitions to atomic, but it is deprecated. Instead
-	 * @enable and @disable should be used.
-	 */
-	void (*dpms)(struct drm_encoder *encoder, int mode);
-
-	/**
-	 * @mode_valid:
-	 *
-	 * This callback is used to check if a specific mode is valid in this
-	 * encoder. This should be implemented if the encoder has some sort
-	 * of restriction in the modes it can display. For example, a given
-	 * encoder may be responsible to set a clock value. If the clock can
-	 * not produce all the values for the available modes then this callback
-	 * can be used to restrict the number of modes to only the ones that
-	 * can be displayed.
-	 *
-	 * This hook is used by the probe helpers to filter the mode list in
-	 * drm_helper_probe_single_connector_modes(), and it is used by the
-	 * atomic helpers to validate modes supplied by userspace in
-	 * drm_atomic_helper_check_modeset().
-	 *
-	 * This function is optional.
-	 *
-	 * NOTE:
-	 *
-	 * Since this function is both called from the check phase of an atomic
-	 * commit, and the mode validation in the probe paths it is not allowed
-	 * to look at anything else but the passed-in mode, and validate it
-	 * against configuration-invariant hardware constraints. Any further
-	 * limits which depend upon the configuration can only be checked in
-	 * @mode_fixup or @atomic_check.
-	 *
-	 * RETURNS:
-	 *
-	 * drm_mode_status Enum
-	 */
-	enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc,
-					   const struct drm_display_mode *mode);
-
-	/**
-	 * @mode_fixup:
-	 *
-	 * This callback is used to validate and adjust a mode. The parameter
-	 * mode is the display mode that should be fed to the next element in
-	 * the display chain, either the final &drm_connector or a &drm_bridge.
-	 * The parameter adjusted_mode is the input mode the encoder requires. It
-	 * can be modified by this callback and does not need to match mode. See
-	 * also &drm_crtc_state.adjusted_mode for more details.
-	 *
-	 * This function is used by both legacy CRTC helpers and atomic helpers.
-	 * This hook is optional.
-	 *
-	 * NOTE:
-	 *
-	 * This function is called in the check phase of atomic modesets, which
-	 * can be aborted for any reason (including on userspace's request to
-	 * just check whether a configuration would be possible). Atomic drivers
-	 * MUST NOT touch any persistent state (hardware or software) or data
-	 * structures except the passed in adjusted_mode parameter.
-	 *
-	 * This is in contrast to the legacy CRTC helpers where this was
-	 * allowed.
-	 *
-	 * Atomic drivers which need to inspect and adjust more state should
-	 * instead use the @atomic_check callback. If @atomic_check is used,
-	 * this hook isn't called since @atomic_check allows a strict superset
-	 * of the functionality of @mode_fixup.
-	 *
-	 * Also beware that userspace can request its own custom modes, neither
-	 * core nor helpers filter modes to the list of probe modes reported by
-	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
-	 * that modes are filtered consistently put any encoder constraints and
-	 * limits checks into @mode_valid.
-	 *
-	 * RETURNS:
-	 *
-	 * True if an acceptable configuration is possible, false if the modeset
-	 * operation should be rejected.
-	 */
-	bool (*mode_fixup)(struct drm_encoder *encoder,
-			   const struct drm_display_mode *mode,
-			   struct drm_display_mode *adjusted_mode);
-
-	/**
-	 * @prepare:
-	 *
-	 * This callback should prepare the encoder for a subsequent modeset,
-	 * which in practice means the driver should disable the encoder if it
-	 * is running. Most drivers ended up implementing this by calling their
-	 * @dpms hook with DRM_MODE_DPMS_OFF.
-	 *
-	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
-	 * also support using this hook for disabling an encoder to facilitate
-	 * transitions to atomic, but it is deprecated. Instead @disable should
-	 * be used.
-	 */
-	void (*prepare)(struct drm_encoder *encoder);
-
-	/**
-	 * @commit:
-	 *
-	 * This callback should commit the new mode on the encoder after a modeset,
-	 * which in practice means the driver should enable the encoder.  Most
-	 * drivers ended up implementing this by calling their @dpms hook with
-	 * DRM_MODE_DPMS_ON.
-	 *
-	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
-	 * also support using this hook for enabling an encoder to facilitate
-	 * transitions to atomic, but it is deprecated. Instead @enable should
-	 * be used.
-	 */
-	void (*commit)(struct drm_encoder *encoder);
-
-	/**
-	 * @mode_set:
-	 *
-	 * This callback is used to update the display mode of an encoder.
-	 *
-	 * Note that the display pipe is completely off when this function is
-	 * called. Drivers which need hardware to be running before they program
-	 * the new display mode (because they implement runtime PM) should not
-	 * use this hook, because the helper library calls it only once and not
-	 * every time the display pipeline is suspend using either DPMS or the
-	 * new "ACTIVE" property. Such drivers should instead move all their
-	 * encoder setup into the @enable callback.
-	 *
-	 * This callback is used both by the legacy CRTC helpers and the atomic
-	 * modeset helpers. It is optional in the atomic helpers.
-	 *
-	 * NOTE:
-	 *
-	 * If the driver uses the atomic modeset helpers and needs to inspect
-	 * the connector state or connector display info during mode setting,
-	 * @atomic_mode_set can be used instead.
-	 */
-	void (*mode_set)(struct drm_encoder *encoder,
-			 struct drm_display_mode *mode,
-			 struct drm_display_mode *adjusted_mode);
-
-	/**
-	 * @atomic_mode_set:
-	 *
-	 * This callback is used to update the display mode of an encoder.
-	 *
-	 * Note that the display pipe is completely off when this function is
-	 * called. Drivers which need hardware to be running before they program
-	 * the new display mode (because they implement runtime PM) should not
-	 * use this hook, because the helper library calls it only once and not
-	 * every time the display pipeline is suspended using either DPMS or the
-	 * new "ACTIVE" property. Such drivers should instead move all their
-	 * encoder setup into the @enable callback.
-	 *
-	 * This callback is used by the atomic modeset helpers in place of the
-	 * @mode_set callback, if set by the driver. It is optional and should
-	 * be used instead of @mode_set if the driver needs to inspect the
-	 * connector state or display info, since there is no direct way to
-	 * go from the encoder to the current connector.
-	 */
-	void (*atomic_mode_set)(struct drm_encoder *encoder,
-				struct drm_crtc_state *crtc_state,
-				struct drm_connector_state *conn_state);
-
-	/**
-	 * @detect:
-	 *
-	 * This callback can be used by drivers who want to do detection on the
-	 * encoder object instead of in connector functions.
-	 *
-	 * It is not used by any helper and therefore has purely driver-specific
-	 * semantics. New drivers shouldn't use this and instead just implement
-	 * their own private callbacks.
-	 *
-	 * FIXME:
-	 *
-	 * This should just be converted into a pile of driver vfuncs.
-	 * Currently radeon, amdgpu and nouveau are using it.
-	 */
-	enum drm_connector_status (*detect)(struct drm_encoder *encoder,
-					    struct drm_connector *connector);
-
-	/**
-	 * @atomic_disable:
-	 *
-	 * This callback should be used to disable the encoder. With the atomic
-	 * drivers it is called before this encoder's CRTC has been shut off
-	 * using their own &drm_crtc_helper_funcs.atomic_disable hook. If that
-	 * sequence is too simple drivers can just add their own driver private
-	 * encoder hooks and call them from CRTC's callback by looping over all
-	 * encoders connected to it using for_each_encoder_on_crtc().
-	 *
-	 * This callback is a variant of @disable that provides the atomic state
-	 * to the driver. If @atomic_disable is implemented, @disable is not
-	 * called by the helpers.
-	 *
-	 * This hook is only used by atomic helpers. Atomic drivers don't need
-	 * to implement it if there's no need to disable anything at the encoder
-	 * level. To ensure that runtime PM handling (using either DPMS or the
-	 * new "ACTIVE" property) works @atomic_disable must be the inverse of
-	 * @atomic_enable.
-	 */
-	void (*atomic_disable)(struct drm_encoder *encoder,
-			       struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_enable:
-	 *
-	 * This callback should be used to enable the encoder. It is called
-	 * after this encoder's CRTC has been enabled using their own
-	 * &drm_crtc_helper_funcs.atomic_enable hook. If that sequence is
-	 * too simple drivers can just add their own driver private encoder
-	 * hooks and call them from CRTC's callback by looping over all encoders
-	 * connected to it using for_each_encoder_on_crtc().
-	 *
-	 * This callback is a variant of @enable that provides the atomic state
-	 * to the driver. If @atomic_enable is implemented, @enable is not
-	 * called by the helpers.
-	 *
-	 * This hook is only used by atomic helpers, it is the opposite of
-	 * @atomic_disable. Atomic drivers don't need to implement it if there's
-	 * no need to enable anything at the encoder level. To ensure that
-	 * runtime PM handling works @atomic_enable must be the inverse of
-	 * @atomic_disable.
-	 */
-	void (*atomic_enable)(struct drm_encoder *encoder,
-			      struct drm_atomic_state *state);
-
-	/**
-	 * @disable:
-	 *
-	 * This callback should be used to disable the encoder. With the atomic
-	 * drivers it is called before this encoder's CRTC has been shut off
-	 * using their own &drm_crtc_helper_funcs.disable hook.  If that
-	 * sequence is too simple drivers can just add their own driver private
-	 * encoder hooks and call them from CRTC's callback by looping over all
-	 * encoders connected to it using for_each_encoder_on_crtc().
-	 *
-	 * This hook is used both by legacy CRTC helpers and atomic helpers.
-	 * Atomic drivers don't need to implement it if there's no need to
-	 * disable anything at the encoder level. To ensure that runtime PM
-	 * handling (using either DPMS or the new "ACTIVE" property) works
-	 * @disable must be the inverse of @enable for atomic drivers.
-	 *
-	 * For atomic drivers also consider @atomic_disable and save yourself
-	 * from having to read the NOTE below!
-	 *
-	 * NOTE:
-	 *
-	 * With legacy CRTC helpers there's a big semantic difference between
-	 * @disable and other hooks (like @prepare or @dpms) used to shut down a
-	 * encoder: @disable is only called when also logically disabling the
-	 * display pipeline and needs to release any resources acquired in
-	 * @mode_set (like shared PLLs, or again release pinned framebuffers).
-	 *
-	 * Therefore @disable must be the inverse of @mode_set plus @commit for
-	 * drivers still using legacy CRTC helpers, which is different from the
-	 * rules under atomic.
-	 */
-	void (*disable)(struct drm_encoder *encoder);
-
-	/**
-	 * @enable:
-	 *
-	 * This callback should be used to enable the encoder. With the atomic
-	 * drivers it is called after this encoder's CRTC has been enabled using
-	 * their own &drm_crtc_helper_funcs.enable hook.  If that sequence is
-	 * too simple drivers can just add their own driver private encoder
-	 * hooks and call them from CRTC's callback by looping over all encoders
-	 * connected to it using for_each_encoder_on_crtc().
-	 *
-	 * This hook is only used by atomic helpers, it is the opposite of
-	 * @disable. Atomic drivers don't need to implement it if there's no
-	 * need to enable anything at the encoder level. To ensure that
-	 * runtime PM handling (using either DPMS or the new "ACTIVE" property)
-	 * works @enable must be the inverse of @disable for atomic drivers.
-	 */
-	void (*enable)(struct drm_encoder *encoder);
-
-	/**
-	 * @atomic_check:
-	 *
-	 * This callback is used to validate encoder state for atomic drivers.
-	 * Since the encoder is the object connecting the CRTC and connector it
-	 * gets passed both states, to be able to validate interactions and
-	 * update the CRTC to match what the encoder needs for the requested
-	 * connector.
-	 *
-	 * Since this provides a strict superset of the functionality of
-	 * @mode_fixup (the requested and adjusted modes are both available
-	 * through the passed in &struct drm_crtc_state) @mode_fixup is not
-	 * called when @atomic_check is implemented.
-	 *
-	 * This function is used by the atomic helpers, but it is optional.
-	 *
-	 * NOTE:
-	 *
-	 * This function is called in the check phase of an atomic update. The
-	 * driver is not allowed to change anything outside of the free-standing
-	 * state objects passed-in or assembled in the overall &drm_atomic_state
-	 * update tracking structure.
-	 *
-	 * Also beware that userspace can request its own custom modes, neither
-	 * core nor helpers filter modes to the list of probe modes reported by
-	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
-	 * that modes are filtered consistently put any encoder constraints and
-	 * limits checks into @mode_valid.
-	 *
-	 * RETURNS:
-	 *
-	 * 0 on success, -EINVAL if the state or the transition can't be
-	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
-	 * attempt to obtain another state object ran into a &drm_modeset_lock
-	 * deadlock.
-	 */
-	int (*atomic_check)(struct drm_encoder *encoder,
-			    struct drm_crtc_state *crtc_state,
-			    struct drm_connector_state *conn_state);
-};
-
-/**
- * drm_encoder_helper_add - sets the helper vtable for an encoder
- * @encoder: DRM encoder
- * @funcs: helper vtable to set for @encoder
- */
-static inline void drm_encoder_helper_add(struct drm_encoder *encoder,
-					  const struct drm_encoder_helper_funcs *funcs)
-{
-	encoder->helper_private = funcs;
-}
-
-/**
- * struct drm_connector_helper_funcs - helper operations for connectors
- *
- * These functions are used by the atomic and legacy modeset helpers and by the
- * probe helpers.
- */
-struct drm_connector_helper_funcs {
-	/**
-	 * @get_modes:
-	 *
-	 * This function should fill in all modes currently valid for the sink
-	 * into the &drm_connector.probed_modes list. It should also update the
-	 * EDID property by calling drm_connector_update_edid_property().
-	 *
-	 * The usual way to implement this is to cache the EDID retrieved in the
-	 * probe callback somewhere in the driver-private connector structure.
-	 * In this function drivers then parse the modes in the EDID and add
-	 * them by calling drm_add_edid_modes(). But connectors that drive a
-	 * fixed panel can also manually add specific modes using
-	 * drm_mode_probed_add(). Drivers which manually add modes should also
-	 * make sure that the &drm_connector.display_info,
-	 * &drm_connector.width_mm and &drm_connector.height_mm fields are
-	 * filled in.
-	 *
-	 * Note that the caller function will automatically add standard VESA
-	 * DMT modes up to 1024x768 if the .get_modes() helper operation returns
-	 * no mode and if the connector status is connector_status_connected or
-	 * connector_status_unknown. There is no need to call
-	 * drm_add_modes_noedid() manually in that case.
-	 *
-	 * Virtual drivers that just want some standard VESA mode with a given
-	 * resolution can call drm_add_modes_noedid(), and mark the preferred
-	 * one using drm_set_preferred_mode().
-	 *
-	 * This function is only called after the @detect hook has indicated
-	 * that a sink is connected and when the EDID isn't overridden through
-	 * sysfs or the kernel commandline.
-	 *
-	 * This callback is used by the probe helpers in e.g.
-	 * drm_helper_probe_single_connector_modes().
-	 *
-	 * To avoid races with concurrent connector state updates, the helper
-	 * libraries always call this with the &drm_mode_config.connection_mutex
-	 * held. Because of this it's safe to inspect &drm_connector->state.
-	 *
-	 * RETURNS:
-	 *
-	 * The number of modes added by calling drm_mode_probed_add().
-	 */
-	int (*get_modes)(struct drm_connector *connector);
-
-	/**
-	 * @detect_ctx:
-	 *
-	 * Check to see if anything is attached to the connector. The parameter
-	 * force is set to false whilst polling, true when checking the
-	 * connector due to a user request. force can be used by the driver to
-	 * avoid expensive, destructive operations during automated probing.
-	 *
-	 * This callback is optional, if not implemented the connector will be
-	 * considered as always being attached.
-	 *
-	 * This is the atomic version of &drm_connector_funcs.detect.
-	 *
-	 * To avoid races against concurrent connector state updates, the
-	 * helper libraries always call this with ctx set to a valid context,
-	 * and &drm_mode_config.connection_mutex will always be locked with
-	 * the ctx parameter set to this ctx. This allows taking additional
-	 * locks as required.
-	 *
-	 * RETURNS:
-	 *
-	 * &drm_connector_status indicating the connector's status,
-	 * or the error code returned by drm_modeset_lock(), -EDEADLK.
-	 */
-	int (*detect_ctx)(struct drm_connector *connector,
-			  struct drm_modeset_acquire_ctx *ctx,
-			  bool force);
-
-	/**
-	 * @mode_valid:
-	 *
-	 * Callback to validate a mode for a connector, irrespective of the
-	 * specific display configuration.
-	 *
-	 * This callback is used by the probe helpers to filter the mode list
-	 * (which is usually derived from the EDID data block from the sink).
-	 * See e.g. drm_helper_probe_single_connector_modes().
-	 *
-	 * This function is optional.
-	 *
-	 * NOTE:
-	 *
-	 * This only filters the mode list supplied to userspace in the
-	 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid,
-	 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid,
-	 * which are also called by the atomic helpers from
-	 * drm_atomic_helper_check_modeset(). This allows userspace to force and
-	 * ignore sink constraint (like the pixel clock limits in the screen's
-	 * EDID), which is useful for e.g. testing, or working around a broken
-	 * EDID. Any source hardware constraint (which always need to be
-	 * enforced) therefore should be checked in one of the above callbacks,
-	 * and not this one here.
-	 *
-	 * To avoid races with concurrent connector state updates, the helper
-	 * libraries always call this with the &drm_mode_config.connection_mutex
-	 * held. Because of this it's safe to inspect &drm_connector->state.
-         *
-	 * RETURNS:
-	 *
-	 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum
-	 * drm_mode_status.
-	 */
-	enum drm_mode_status (*mode_valid)(struct drm_connector *connector,
-					   struct drm_display_mode *mode);
-
-	/**
-	 * @mode_valid_ctx:
-	 *
-	 * Callback to validate a mode for a connector, irrespective of the
-	 * specific display configuration.
-	 *
-	 * This callback is used by the probe helpers to filter the mode list
-	 * (which is usually derived from the EDID data block from the sink).
-	 * See e.g. drm_helper_probe_single_connector_modes().
-	 *
-	 * This function is optional, and is the atomic version of
-	 * &drm_connector_helper_funcs.mode_valid.
-	 *
-	 * To allow for accessing the atomic state of modesetting objects, the
-	 * helper libraries always call this with ctx set to a valid context,
-	 * and &drm_mode_config.connection_mutex will always be locked with
-	 * the ctx parameter set to @ctx. This allows for taking additional
-	 * locks as required.
-	 *
-	 * Even though additional locks may be acquired, this callback is
-	 * still expected not to take any constraints into account which would
-	 * be influenced by the currently set display state - such constraints
-	 * should be handled in the driver's atomic check. For example, if a
-	 * connector shares display bandwidth with other connectors then it
-	 * would be ok to validate the minimum bandwidth requirement of a mode
-	 * against the maximum possible bandwidth of the connector. But it
-	 * wouldn't be ok to take the current bandwidth usage of other
-	 * connectors into account, as this would change depending on the
-	 * display state.
-	 *
-	 * Returns:
-	 * 0 if &drm_connector_helper_funcs.mode_valid_ctx succeeded and wrote
-	 * the &enum drm_mode_status value to @status, or a negative error
-	 * code otherwise.
-	 *
-	 */
-	int (*mode_valid_ctx)(struct drm_connector *connector,
-			      struct drm_display_mode *mode,
-			      struct drm_modeset_acquire_ctx *ctx,
-			      enum drm_mode_status *status);
-
-	/**
-	 * @best_encoder:
-	 *
-	 * This function should select the best encoder for the given connector.
-	 *
-	 * This function is used by both the atomic helpers (in the
-	 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC
-	 * helpers.
-	 *
-	 * NOTE:
-	 *
-	 * In atomic drivers this function is called in the check phase of an
-	 * atomic update. The driver is not allowed to change or inspect
-	 * anything outside of arguments passed-in. Atomic drivers which need to
-	 * inspect dynamic configuration state should instead use
-	 * @atomic_best_encoder.
-	 *
-	 * You can leave this function to NULL if the connector is only
-	 * attached to a single encoder. In this case, the core will call
-	 * drm_connector_get_single_encoder() for you.
-	 *
-	 * RETURNS:
-	 *
-	 * Encoder that should be used for the given connector and connector
-	 * state, or NULL if no suitable encoder exists. Note that the helpers
-	 * will ensure that encoders aren't used twice, drivers should not check
-	 * for this.
-	 */
-	struct drm_encoder *(*best_encoder)(struct drm_connector *connector);
-
-	/**
-	 * @atomic_best_encoder:
-	 *
-	 * This is the atomic version of @best_encoder for atomic drivers which
-	 * need to select the best encoder depending upon the desired
-	 * configuration and can't select it statically.
-	 *
-	 * This function is used by drm_atomic_helper_check_modeset().
-	 * If it is not implemented, the core will fallback to @best_encoder
-	 * (or drm_connector_get_single_encoder() if @best_encoder is NULL).
-	 *
-	 * NOTE:
-	 *
-	 * This function is called in the check phase of an atomic update. The
-	 * driver is not allowed to change anything outside of the
-	 * &drm_atomic_state update tracking structure passed in.
-	 *
-	 * RETURNS:
-	 *
-	 * Encoder that should be used for the given connector and connector
-	 * state, or NULL if no suitable encoder exists. Note that the helpers
-	 * will ensure that encoders aren't used twice, drivers should not check
-	 * for this.
-	 */
-	struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector,
-						   struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_check:
-	 *
-	 * This hook is used to validate connector state. This function is
-	 * called from &drm_atomic_helper_check_modeset, and is called when
-	 * a connector property is set, or a modeset on the crtc is forced.
-	 *
-	 * Because &drm_atomic_helper_check_modeset may be called multiple times,
-	 * this function should handle being called multiple times as well.
-	 *
-	 * This function is also allowed to inspect any other object's state and
-	 * can add more state objects to the atomic commit if needed. Care must
-	 * be taken though to ensure that state check and compute functions for
-	 * these added states are all called, and derived state in other objects
-	 * all updated. Again the recommendation is to just call check helpers
-	 * until a maximal configuration is reached.
-	 *
-	 * NOTE:
-	 *
-	 * This function is called in the check phase of an atomic update. The
-	 * driver is not allowed to change anything outside of the free-standing
-	 * state objects passed-in or assembled in the overall &drm_atomic_state
-	 * update tracking structure.
-	 *
-	 * RETURNS:
-	 *
-	 * 0 on success, -EINVAL if the state or the transition can't be
-	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
-	 * attempt to obtain another state object ran into a &drm_modeset_lock
-	 * deadlock.
-	 */
-	int (*atomic_check)(struct drm_connector *connector,
-			    struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_commit:
-	 *
-	 * This hook is to be used by drivers implementing writeback connectors
-	 * that need a point when to commit the writeback job to the hardware.
-	 * The writeback_job to commit is available in the new connector state,
-	 * in &drm_connector_state.writeback_job.
-	 *
-	 * This hook is optional.
-	 *
-	 * This callback is used by the atomic modeset helpers.
-	 */
-	void (*atomic_commit)(struct drm_connector *connector,
-			      struct drm_atomic_state *state);
-
-	/**
-	 * @prepare_writeback_job:
-	 *
-	 * As writeback jobs contain a framebuffer, drivers may need to
-	 * prepare and clean them up the same way they can prepare and
-	 * clean up framebuffers for planes. This optional connector operation
-	 * is used to support the preparation of writeback jobs. The job
-	 * prepare operation is called from drm_atomic_helper_prepare_planes()
-	 * for struct &drm_writeback_connector connectors only.
-	 *
-	 * This operation is optional.
-	 *
-	 * This callback is used by the atomic modeset helpers.
-	 */
-	int (*prepare_writeback_job)(struct drm_writeback_connector *connector,
-				     struct drm_writeback_job *job);
-	/**
-	 * @cleanup_writeback_job:
-	 *
-	 * This optional connector operation is used to support the
-	 * cleanup of writeback jobs. The job cleanup operation is called
-	 * from the existing drm_writeback_cleanup_job() function, invoked
-	 * both when destroying the job as part of an aborted commit, or when
-	 * the job completes.
-	 *
-	 * This operation is optional.
-	 *
-	 * This callback is used by the atomic modeset helpers.
-	 */
-	void (*cleanup_writeback_job)(struct drm_writeback_connector *connector,
-				      struct drm_writeback_job *job);
-
-	/**
-	 * @enable_hpd:
-	 *
-	 * Enable hot-plug detection for the connector.
-	 *
-	 * This operation is optional.
-	 *
-	 * This callback is used by the drm_kms_helper_poll_enable() helpers.
-	 */
-	void (*enable_hpd)(struct drm_connector *connector);
-
-	/**
-	 * @disable_hpd:
-	 *
-	 * Disable hot-plug detection for the connector.
-	 *
-	 * This operation is optional.
-	 *
-	 * This callback is used by the drm_kms_helper_poll_disable() helpers.
-	 */
-	void (*disable_hpd)(struct drm_connector *connector);
-};
-
-/**
- * drm_connector_helper_add - sets the helper vtable for a connector
- * @connector: DRM connector
- * @funcs: helper vtable to set for @connector
- */
-static inline void drm_connector_helper_add(struct drm_connector *connector,
-					    const struct drm_connector_helper_funcs *funcs)
-{
-	connector->helper_private = funcs;
-}
-
-/**
- * struct drm_plane_helper_funcs - helper operations for planes
- *
- * These functions are used by the atomic helpers.
- */
-struct drm_plane_helper_funcs {
-	/**
-	 * @prepare_fb:
-	 *
-	 * This hook is to prepare a framebuffer for scanout by e.g. pinning
-	 * its backing storage or relocating it into a contiguous block of
-	 * VRAM. Other possible preparatory work includes flushing caches.
-	 *
-	 * This function must not block for outstanding rendering, since it is
-	 * called in the context of the atomic IOCTL even for async commits to
-	 * be able to return any errors to userspace. Instead the recommended
-	 * way is to fill out the &drm_plane_state.fence of the passed-in
-	 * &drm_plane_state. If the driver doesn't support native fences then
-	 * equivalent functionality should be implemented through private
-	 * members in the plane structure.
-	 *
-	 * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook
-	 * set drm_gem_plane_helper_prepare_fb() is called automatically to
-	 * implement this. Other drivers which need additional plane processing
-	 * can call drm_gem_plane_helper_prepare_fb() from their @prepare_fb
-	 * hook.
-	 *
-	 * The resources acquired in @prepare_fb persist after the end of
-	 * the atomic commit. Resources that can be release at the commit's end
-	 * should be acquired in @begin_fb_access and released in @end_fb_access.
-	 * For example, a GEM buffer's pin operation belongs into @prepare_fb to
-	 * keep the buffer pinned after the commit. But a vmap operation for
-	 * shadow-plane helpers belongs into @begin_fb_access, so that atomic
-	 * helpers remove the mapping at the end of the commit.
-	 *
-	 * The helpers will call @cleanup_fb with matching arguments for every
-	 * successful call to this hook.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is
-	 * optional. See @begin_fb_access for preparing per-commit resources.
-	 *
-	 * RETURNS:
-	 *
-	 * 0 on success or one of the following negative error codes allowed by
-	 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers
-	 * this callback is the only one which can fail an atomic commit,
-	 * everything else must complete successfully.
-	 */
-	int (*prepare_fb)(struct drm_plane *plane,
-			  struct drm_plane_state *new_state);
-	/**
-	 * @cleanup_fb:
-	 *
-	 * This hook is called to clean up any resources allocated for the given
-	 * framebuffer and plane configuration in @prepare_fb.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is
-	 * optional.
-	 */
-	void (*cleanup_fb)(struct drm_plane *plane,
-			   struct drm_plane_state *old_state);
-
-	/**
-	 * @begin_fb_access:
-	 *
-	 * This hook prepares the plane for access during an atomic commit.
-	 * In contrast to @prepare_fb, resources acquired in @begin_fb_access,
-	 * are released at the end of the atomic commit in @end_fb_access.
-	 *
-	 * For example, with shadow-plane helpers, the GEM buffer's vmap
-	 * operation belongs into @begin_fb_access, so that the buffer's
-	 * memory will be unmapped at the end of the commit in @end_fb_access.
-	 * But a GEM buffer's pin operation belongs into @prepare_fb
-	 * to keep the buffer pinned after the commit.
-	 *
-	 * The callback is used by the atomic modeset helpers, but it is optional.
-	 * See @end_fb_cleanup for undoing the effects of @begin_fb_access and
-	 * @prepare_fb for acquiring resources until the next pageflip.
-	 *
-	 * Returns:
-	 * 0 on success, or a negative errno code otherwise.
-	 */
-	int (*begin_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
-
-	/**
-	 * @end_fb_access:
-	 *
-	 * This hook cleans up resources allocated by @begin_fb_access. It it called
-	 * at the end of a commit for the new plane state.
-	 */
-	void (*end_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
-
-	/**
-	 * @atomic_check:
-	 *
-	 * Drivers should check plane specific constraints in this hook.
-	 *
-	 * When using drm_atomic_helper_check_planes() plane's @atomic_check
-	 * hooks are called before the ones for CRTCs, which allows drivers to
-	 * request shared resources that the CRTC controls here. For more
-	 * complicated dependencies the driver can call the provided check helpers
-	 * multiple times until the computed state has a final configuration and
-	 * everything has been checked.
-	 *
-	 * This function is also allowed to inspect any other object's state and
-	 * can add more state objects to the atomic commit if needed. Care must
-	 * be taken though to ensure that state check and compute functions for
-	 * these added states are all called, and derived state in other objects
-	 * all updated. Again the recommendation is to just call check helpers
-	 * until a maximal configuration is reached.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is
-	 * optional.
-	 *
-	 * NOTE:
-	 *
-	 * This function is called in the check phase of an atomic update. The
-	 * driver is not allowed to change anything outside of the
-	 * &drm_atomic_state update tracking structure.
-	 *
-	 * RETURNS:
-	 *
-	 * 0 on success, -EINVAL if the state or the transition can't be
-	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
-	 * attempt to obtain another state object ran into a &drm_modeset_lock
-	 * deadlock.
-	 */
-	int (*atomic_check)(struct drm_plane *plane,
-			    struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_update:
-	 *
-	 * Drivers should use this function to update the plane state.  This
-	 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and
-	 * drm_crtc_helper_funcs.atomic_flush callbacks.
-	 *
-	 * Note that the power state of the display pipe when this function is
-	 * called depends upon the exact helpers and calling sequence the driver
-	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
-	 * the tradeoffs and variants of plane commit helpers.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is optional.
-	 */
-	void (*atomic_update)(struct drm_plane *plane,
-			      struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_enable:
-	 *
-	 * Drivers should use this function to unconditionally enable a plane.
-	 * This hook is called in-between the &drm_crtc_helper_funcs.atomic_begin
-	 * and drm_crtc_helper_funcs.atomic_flush callbacks. It is called after
-	 * @atomic_update, which will be called for all enabled planes. Drivers
-	 * that use @atomic_enable should set up a plane in @atomic_update and
-	 * afterwards enable the plane in @atomic_enable. If a plane needs to be
-	 * enabled before installing the scanout buffer, drivers can still do
-	 * so in @atomic_update.
-	 *
-	 * Note that the power state of the display pipe when this function is
-	 * called depends upon the exact helpers and calling sequence the driver
-	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
-	 * the tradeoffs and variants of plane commit helpers.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is
-	 * optional. If implemented, @atomic_enable should be the inverse of
-	 * @atomic_disable. Drivers that don't want to use either can still
-	 * implement the complete plane update in @atomic_update.
-	 */
-	void (*atomic_enable)(struct drm_plane *plane,
-			      struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_disable:
-	 *
-	 * Drivers should use this function to unconditionally disable a plane.
-	 * This hook is called in-between the
-	 * &drm_crtc_helper_funcs.atomic_begin and
-	 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to
-	 * @atomic_update, which will be called for disabling planes, too, if
-	 * the @atomic_disable hook isn't implemented.
-	 *
-	 * This hook is also useful to disable planes in preparation of a modeset,
-	 * by calling drm_atomic_helper_disable_planes_on_crtc() from the
-	 * &drm_crtc_helper_funcs.disable hook.
-	 *
-	 * Note that the power state of the display pipe when this function is
-	 * called depends upon the exact helpers and calling sequence the driver
-	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
-	 * the tradeoffs and variants of plane commit helpers.
-	 *
-	 * This callback is used by the atomic modeset helpers, but it is
-	 * optional. It's intended to reverse the effects of @atomic_enable.
-	 */
-	void (*atomic_disable)(struct drm_plane *plane,
-			       struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_async_check:
-	 *
-	 * Drivers should set this function pointer to check if the plane's
-	 * atomic state can be updated in a async fashion. Here async means
-	 * "not vblank synchronized".
-	 *
-	 * This hook is called by drm_atomic_async_check() to establish if a
-	 * given update can be committed asynchronously, that is, if it can
-	 * jump ahead of the state currently queued for update.
-	 *
-	 * RETURNS:
-	 *
-	 * Return 0 on success and any error returned indicates that the update
-	 * can not be applied in asynchronous manner.
-	 */
-	int (*atomic_async_check)(struct drm_plane *plane,
-				  struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_async_update:
-	 *
-	 * Drivers should set this function pointer to perform asynchronous
-	 * updates of planes, that is, jump ahead of the currently queued
-	 * state and update the plane. Here async means "not vblank
-	 * synchronized".
-	 *
-	 * This hook is called by drm_atomic_helper_async_commit().
-	 *
-	 * An async update will happen on legacy cursor updates. An async
-	 * update won't happen if there is an outstanding commit modifying
-	 * the same plane.
-	 *
-	 * When doing async_update drivers shouldn't replace the
-	 * &drm_plane_state but update the current one with the new plane
-	 * configurations in the new plane_state.
-	 *
-	 * Drivers should also swap the framebuffers between current plane
-	 * state (&drm_plane.state) and new_state.
-	 * This is required since cleanup for async commits is performed on
-	 * the new state, rather than old state like for traditional commits.
-	 * Since we want to give up the reference on the current (old) fb
-	 * instead of our brand new one, swap them in the driver during the
-	 * async commit.
-	 *
-	 * FIXME:
-	 *  - It only works for single plane updates
-	 *  - Async Pageflips are not supported yet
-	 *  - Some hw might still scan out the old buffer until the next
-	 *    vblank, however we let go of the fb references as soon as
-	 *    we run this hook. For now drivers must implement their own workers
-	 *    for deferring if needed, until a common solution is created.
-	 */
-	void (*atomic_async_update)(struct drm_plane *plane,
-				    struct drm_atomic_state *state);
-};
-
-/**
- * drm_plane_helper_add - sets the helper vtable for a plane
- * @plane: DRM plane
- * @funcs: helper vtable to set for @plane
- */
-static inline void drm_plane_helper_add(struct drm_plane *plane,
-					const struct drm_plane_helper_funcs *funcs)
-{
-	plane->helper_private = funcs;
-}
-
-/**
- * struct drm_mode_config_helper_funcs - global modeset helper operations
- *
- * These helper functions are used by the atomic helpers.
- */
-struct drm_mode_config_helper_funcs {
-	/**
-	 * @atomic_commit_tail:
-	 *
-	 * This hook is used by the default atomic_commit() hook implemented in
-	 * drm_atomic_helper_commit() together with the nonblocking commit
-	 * helpers (see drm_atomic_helper_setup_commit() for a starting point)
-	 * to implement blocking and nonblocking commits easily. It is not used
-	 * by the atomic helpers
-	 *
-	 * This function is called when the new atomic state has already been
-	 * swapped into the various state pointers. The passed in state
-	 * therefore contains copies of the old/previous state. This hook should
-	 * commit the new state into hardware. Note that the helpers have
-	 * already waited for preceding atomic commits and fences, but drivers
-	 * can add more waiting calls at the start of their implementation, e.g.
-	 * to wait for driver-internal request for implicit syncing, before
-	 * starting to commit the update to the hardware.
-	 *
-	 * After the atomic update is committed to the hardware this hook needs
-	 * to call drm_atomic_helper_commit_hw_done(). Then wait for the update
-	 * to be executed by the hardware, for example using
-	 * drm_atomic_helper_wait_for_vblanks() or
-	 * drm_atomic_helper_wait_for_flip_done(), and then clean up the old
-	 * framebuffers using drm_atomic_helper_cleanup_planes().
-	 *
-	 * When disabling a CRTC this hook _must_ stall for the commit to
-	 * complete. Vblank waits don't work on disabled CRTC, hence the core
-	 * can't take care of this. And it also can't rely on the vblank event,
-	 * since that can be signalled already when the screen shows black,
-	 * which can happen much earlier than the last hardware access needed to
-	 * shut off the display pipeline completely.
-	 *
-	 * This hook is optional, the default implementation is
-	 * drm_atomic_helper_commit_tail().
-	 */
-	void (*atomic_commit_tail)(struct drm_atomic_state *state);
-
-	/**
-	 * @atomic_commit_setup:
-	 *
-	 * This hook is used by the default atomic_commit() hook implemented in
-	 * drm_atomic_helper_commit() together with the nonblocking helpers (see
-	 * drm_atomic_helper_setup_commit()) to extend the DRM commit setup. It
-	 * is not used by the atomic helpers.
-	 *
-	 * This function is called at the end of
-	 * drm_atomic_helper_setup_commit(), so once the commit has been
-	 * properly setup across the generic DRM object states. It allows
-	 * drivers to do some additional commit tracking that isn't related to a
-	 * CRTC, plane or connector, tracked in a &drm_private_obj structure.
-	 *
-	 * Note that the documentation of &drm_private_obj has more details on
-	 * how one should implement this.
-	 *
-	 * This hook is optional.
-	 */
-	int (*atomic_commit_setup)(struct drm_atomic_state *state);
-};
+#include <drm/drm_crtc_helper_vtable.h>
+#include <drm/drm_encoder_helper_vtable.h>
+#include <drm/drm_connector_helper_vtable.h>
+#include <drm/drm_plane_helper_vtable.h>
+#include <drm/drm_mode_config_helper_vtable.h>
 
 #endif
diff --git a/include/drm/drm_plane_helper_vtable.h b/include/drm/drm_plane_helper_vtable.h
new file mode 100644
index 0000000000000000..e735aa9733869383
--- /dev/null
+++ b/include/drm/drm_plane_helper_vtable.h
@@ -0,0 +1,297 @@
+/*
+ * Copyright © 2006 Keith Packard
+ * Copyright © 2007-2008 Dave Airlie
+ * Copyright © 2007-2008 Intel Corporation
+ *   Jesse Barnes <jesse.barnes@intel.com>
+ * Copyright © 2011-2013 Intel Corporation
+ * Copyright © 2015 Intel Corporation
+ *   Daniel Vetter <daniel.vetter@ffwll.ch>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __DRM_PLANE_HELPER_VTABLE_H__
+#define __DRM_PLANE_HELPER_VTABLE_H__
+
+/**
+ * struct drm_plane_helper_funcs - helper operations for planes
+ *
+ * These functions are used by the atomic helpers.
+ */
+struct drm_plane_helper_funcs {
+	/**
+	 * @prepare_fb:
+	 *
+	 * This hook is to prepare a framebuffer for scanout by e.g. pinning
+	 * its backing storage or relocating it into a contiguous block of
+	 * VRAM. Other possible preparatory work includes flushing caches.
+	 *
+	 * This function must not block for outstanding rendering, since it is
+	 * called in the context of the atomic IOCTL even for async commits to
+	 * be able to return any errors to userspace. Instead the recommended
+	 * way is to fill out the &drm_plane_state.fence of the passed-in
+	 * &drm_plane_state. If the driver doesn't support native fences then
+	 * equivalent functionality should be implemented through private
+	 * members in the plane structure.
+	 *
+	 * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook
+	 * set drm_gem_plane_helper_prepare_fb() is called automatically to
+	 * implement this. Other drivers which need additional plane processing
+	 * can call drm_gem_plane_helper_prepare_fb() from their @prepare_fb
+	 * hook.
+	 *
+	 * The resources acquired in @prepare_fb persist after the end of
+	 * the atomic commit. Resources that can be release at the commit's end
+	 * should be acquired in @begin_fb_access and released in @end_fb_access.
+	 * For example, a GEM buffer's pin operation belongs into @prepare_fb to
+	 * keep the buffer pinned after the commit. But a vmap operation for
+	 * shadow-plane helpers belongs into @begin_fb_access, so that atomic
+	 * helpers remove the mapping at the end of the commit.
+	 *
+	 * The helpers will call @cleanup_fb with matching arguments for every
+	 * successful call to this hook.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is
+	 * optional. See @begin_fb_access for preparing per-commit resources.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success or one of the following negative error codes allowed by
+	 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers
+	 * this callback is the only one which can fail an atomic commit,
+	 * everything else must complete successfully.
+	 */
+	int (*prepare_fb)(struct drm_plane *plane,
+			  struct drm_plane_state *new_state);
+	/**
+	 * @cleanup_fb:
+	 *
+	 * This hook is called to clean up any resources allocated for the given
+	 * framebuffer and plane configuration in @prepare_fb.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is
+	 * optional.
+	 */
+	void (*cleanup_fb)(struct drm_plane *plane,
+			   struct drm_plane_state *old_state);
+
+	/**
+	 * @begin_fb_access:
+	 *
+	 * This hook prepares the plane for access during an atomic commit.
+	 * In contrast to @prepare_fb, resources acquired in @begin_fb_access,
+	 * are released at the end of the atomic commit in @end_fb_access.
+	 *
+	 * For example, with shadow-plane helpers, the GEM buffer's vmap
+	 * operation belongs into @begin_fb_access, so that the buffer's
+	 * memory will be unmapped at the end of the commit in @end_fb_access.
+	 * But a GEM buffer's pin operation belongs into @prepare_fb
+	 * to keep the buffer pinned after the commit.
+	 *
+	 * The callback is used by the atomic modeset helpers, but it is optional.
+	 * See @end_fb_cleanup for undoing the effects of @begin_fb_access and
+	 * @prepare_fb for acquiring resources until the next pageflip.
+	 *
+	 * Returns:
+	 * 0 on success, or a negative errno code otherwise.
+	 */
+	int (*begin_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
+
+	/**
+	 * @end_fb_access:
+	 *
+	 * This hook cleans up resources allocated by @begin_fb_access. It it called
+	 * at the end of a commit for the new plane state.
+	 */
+	void (*end_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
+
+	/**
+	 * @atomic_check:
+	 *
+	 * Drivers should check plane specific constraints in this hook.
+	 *
+	 * When using drm_atomic_helper_check_planes() plane's @atomic_check
+	 * hooks are called before the ones for CRTCs, which allows drivers to
+	 * request shared resources that the CRTC controls here. For more
+	 * complicated dependencies the driver can call the provided check helpers
+	 * multiple times until the computed state has a final configuration and
+	 * everything has been checked.
+	 *
+	 * This function is also allowed to inspect any other object's state and
+	 * can add more state objects to the atomic commit if needed. Care must
+	 * be taken though to ensure that state check and compute functions for
+	 * these added states are all called, and derived state in other objects
+	 * all updated. Again the recommendation is to just call check helpers
+	 * until a maximal configuration is reached.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is
+	 * optional.
+	 *
+	 * NOTE:
+	 *
+	 * This function is called in the check phase of an atomic update. The
+	 * driver is not allowed to change anything outside of the
+	 * &drm_atomic_state update tracking structure.
+	 *
+	 * RETURNS:
+	 *
+	 * 0 on success, -EINVAL if the state or the transition can't be
+	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
+	 * attempt to obtain another state object ran into a &drm_modeset_lock
+	 * deadlock.
+	 */
+	int (*atomic_check)(struct drm_plane *plane,
+			    struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_update:
+	 *
+	 * Drivers should use this function to update the plane state.  This
+	 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and
+	 * drm_crtc_helper_funcs.atomic_flush callbacks.
+	 *
+	 * Note that the power state of the display pipe when this function is
+	 * called depends upon the exact helpers and calling sequence the driver
+	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
+	 * the tradeoffs and variants of plane commit helpers.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is optional.
+	 */
+	void (*atomic_update)(struct drm_plane *plane,
+			      struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_enable:
+	 *
+	 * Drivers should use this function to unconditionally enable a plane.
+	 * This hook is called in-between the &drm_crtc_helper_funcs.atomic_begin
+	 * and drm_crtc_helper_funcs.atomic_flush callbacks. It is called after
+	 * @atomic_update, which will be called for all enabled planes. Drivers
+	 * that use @atomic_enable should set up a plane in @atomic_update and
+	 * afterwards enable the plane in @atomic_enable. If a plane needs to be
+	 * enabled before installing the scanout buffer, drivers can still do
+	 * so in @atomic_update.
+	 *
+	 * Note that the power state of the display pipe when this function is
+	 * called depends upon the exact helpers and calling sequence the driver
+	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
+	 * the tradeoffs and variants of plane commit helpers.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is
+	 * optional. If implemented, @atomic_enable should be the inverse of
+	 * @atomic_disable. Drivers that don't want to use either can still
+	 * implement the complete plane update in @atomic_update.
+	 */
+	void (*atomic_enable)(struct drm_plane *plane,
+			      struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_disable:
+	 *
+	 * Drivers should use this function to unconditionally disable a plane.
+	 * This hook is called in-between the
+	 * &drm_crtc_helper_funcs.atomic_begin and
+	 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to
+	 * @atomic_update, which will be called for disabling planes, too, if
+	 * the @atomic_disable hook isn't implemented.
+	 *
+	 * This hook is also useful to disable planes in preparation of a modeset,
+	 * by calling drm_atomic_helper_disable_planes_on_crtc() from the
+	 * &drm_crtc_helper_funcs.disable hook.
+	 *
+	 * Note that the power state of the display pipe when this function is
+	 * called depends upon the exact helpers and calling sequence the driver
+	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
+	 * the tradeoffs and variants of plane commit helpers.
+	 *
+	 * This callback is used by the atomic modeset helpers, but it is
+	 * optional. It's intended to reverse the effects of @atomic_enable.
+	 */
+	void (*atomic_disable)(struct drm_plane *plane,
+			       struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_async_check:
+	 *
+	 * Drivers should set this function pointer to check if the plane's
+	 * atomic state can be updated in a async fashion. Here async means
+	 * "not vblank synchronized".
+	 *
+	 * This hook is called by drm_atomic_async_check() to establish if a
+	 * given update can be committed asynchronously, that is, if it can
+	 * jump ahead of the state currently queued for update.
+	 *
+	 * RETURNS:
+	 *
+	 * Return 0 on success and any error returned indicates that the update
+	 * can not be applied in asynchronous manner.
+	 */
+	int (*atomic_async_check)(struct drm_plane *plane,
+				  struct drm_atomic_state *state);
+
+	/**
+	 * @atomic_async_update:
+	 *
+	 * Drivers should set this function pointer to perform asynchronous
+	 * updates of planes, that is, jump ahead of the currently queued
+	 * state and update the plane. Here async means "not vblank
+	 * synchronized".
+	 *
+	 * This hook is called by drm_atomic_helper_async_commit().
+	 *
+	 * An async update will happen on legacy cursor updates. An async
+	 * update won't happen if there is an outstanding commit modifying
+	 * the same plane.
+	 *
+	 * When doing async_update drivers shouldn't replace the
+	 * &drm_plane_state but update the current one with the new plane
+	 * configurations in the new plane_state.
+	 *
+	 * Drivers should also swap the framebuffers between current plane
+	 * state (&drm_plane.state) and new_state.
+	 * This is required since cleanup for async commits is performed on
+	 * the new state, rather than old state like for traditional commits.
+	 * Since we want to give up the reference on the current (old) fb
+	 * instead of our brand new one, swap them in the driver during the
+	 * async commit.
+	 *
+	 * FIXME:
+	 *  - It only works for single plane updates
+	 *  - Async Pageflips are not supported yet
+	 *  - Some hw might still scan out the old buffer until the next
+	 *    vblank, however we let go of the fb references as soon as
+	 *    we run this hook. For now drivers must implement their own workers
+	 *    for deferring if needed, until a common solution is created.
+	 */
+	void (*atomic_async_update)(struct drm_plane *plane,
+				    struct drm_atomic_state *state);
+};
+
+/**
+ * drm_plane_helper_add - sets the helper vtable for a plane
+ * @plane: DRM plane
+ * @funcs: helper vtable to set for @plane
+ */
+static inline void drm_plane_helper_add(struct drm_plane *plane,
+					const struct drm_plane_helper_funcs *funcs)
+{
+	plane->helper_private = funcs;
+}
+
+#endif /* __DRM_PLANE_HELPER_VTABLE_H__ */
-- 
2.34.1

Re: [PATCH/RFC 3/3] drm: Split drm_modeset_helper_vtables.h

[Thomas Zimmermann]

[-- Attachment #1.1: Type: text/plain, Size: 140160 bytes --]

Hi Geert

Am 28.09.23 um 14:16 schrieb Geert Uytterhoeven:
> <drm/drm_modeset_helper_vtables.h> is the second largest header file in
> the DRM subsystem, and declares helpers vtables for various DRM
> components.  Several vtables contain methods with the same name, and all
> but one vtable do not fit on the screen, making it hard to navigate to
> the actual method one is interested in.
> 
> Make it easier for the casual reviewer to keep track by splitting
> <drm/drm_modeset_helper_vtables.h> in multiple header files, one per DRM
> component.

I never liked this header either, but do we need new header files? Each 
struct could be appended to the end of the regular header: struct 
drm_plane_helper_funcs to drm_plane.h, drm_connector_helper_func to 
drm_connector.h and so on.

Best regards
Thomas

> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> RFC, a future patch could replace inclusion of
> <drm/drm_modeset_helper_vtables.h> by inclusion of one or more of the
> new files, and reduce compilation time.
> ---
>   include/drm/drm_connector_helper_vtable.h   |  364 +++++
>   include/drm/drm_crtc_helper_vtable.h        |  483 ++++++
>   include/drm/drm_encoder_helper_vtable.h     |  381 +++++
>   include/drm/drm_mode_config_helper_vtable.h |   97 ++
>   include/drm/drm_modeset_helper_vtables.h    | 1466 +------------------
>   include/drm/drm_plane_helper_vtable.h       |  297 ++++
>   6 files changed, 1627 insertions(+), 1461 deletions(-)
>   create mode 100644 include/drm/drm_connector_helper_vtable.h
>   create mode 100644 include/drm/drm_crtc_helper_vtable.h
>   create mode 100644 include/drm/drm_encoder_helper_vtable.h
>   create mode 100644 include/drm/drm_mode_config_helper_vtable.h
>   create mode 100644 include/drm/drm_plane_helper_vtable.h
> 
> diff --git a/include/drm/drm_connector_helper_vtable.h b/include/drm/drm_connector_helper_vtable.h
> new file mode 100644
> index 0000000000000000..92db9784e4e37e02
> --- /dev/null
> +++ b/include/drm/drm_connector_helper_vtable.h
> @@ -0,0 +1,364 @@
> +/*
> + * Copyright © 2006 Keith Packard
> + * Copyright © 2007-2008 Dave Airlie
> + * Copyright © 2007-2008 Intel Corporation
> + *   Jesse Barnes <jesse.barnes@intel.com>
> + * Copyright © 2011-2013 Intel Corporation
> + * Copyright © 2015 Intel Corporation
> + *   Daniel Vetter <daniel.vetter@ffwll.ch>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + */
> +
> +#ifndef __DRM_CONNECTOR_HELPER_VTABLE_H__
> +#define __DRM_CONNECTOR_HELPER_VTABLE_H__
> +
> +struct drm_writeback_connector;
> +struct drm_writeback_job;
> +
> +/**
> + * struct drm_connector_helper_funcs - helper operations for connectors
> + *
> + * These functions are used by the atomic and legacy modeset helpers and by the
> + * probe helpers.
> + */
> +struct drm_connector_helper_funcs {
> +	/**
> +	 * @get_modes:
> +	 *
> +	 * This function should fill in all modes currently valid for the sink
> +	 * into the &drm_connector.probed_modes list. It should also update the
> +	 * EDID property by calling drm_connector_update_edid_property().
> +	 *
> +	 * The usual way to implement this is to cache the EDID retrieved in the
> +	 * probe callback somewhere in the driver-private connector structure.
> +	 * In this function drivers then parse the modes in the EDID and add
> +	 * them by calling drm_add_edid_modes(). But connectors that drive a
> +	 * fixed panel can also manually add specific modes using
> +	 * drm_mode_probed_add(). Drivers which manually add modes should also
> +	 * make sure that the &drm_connector.display_info,
> +	 * &drm_connector.width_mm and &drm_connector.height_mm fields are
> +	 * filled in.
> +	 *
> +	 * Note that the caller function will automatically add standard VESA
> +	 * DMT modes up to 1024x768 if the .get_modes() helper operation returns
> +	 * no mode and if the connector status is connector_status_connected or
> +	 * connector_status_unknown. There is no need to call
> +	 * drm_add_modes_noedid() manually in that case.
> +	 *
> +	 * Virtual drivers that just want some standard VESA mode with a given
> +	 * resolution can call drm_add_modes_noedid(), and mark the preferred
> +	 * one using drm_set_preferred_mode().
> +	 *
> +	 * This function is only called after the @detect hook has indicated
> +	 * that a sink is connected and when the EDID isn't overridden through
> +	 * sysfs or the kernel commandline.
> +	 *
> +	 * This callback is used by the probe helpers in e.g.
> +	 * drm_helper_probe_single_connector_modes().
> +	 *
> +	 * To avoid races with concurrent connector state updates, the helper
> +	 * libraries always call this with the &drm_mode_config.connection_mutex
> +	 * held. Because of this it's safe to inspect &drm_connector->state.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * The number of modes added by calling drm_mode_probed_add().
> +	 */
> +	int (*get_modes)(struct drm_connector *connector);
> +
> +	/**
> +	 * @detect_ctx:
> +	 *
> +	 * Check to see if anything is attached to the connector. The parameter
> +	 * force is set to false whilst polling, true when checking the
> +	 * connector due to a user request. force can be used by the driver to
> +	 * avoid expensive, destructive operations during automated probing.
> +	 *
> +	 * This callback is optional, if not implemented the connector will be
> +	 * considered as always being attached.
> +	 *
> +	 * This is the atomic version of &drm_connector_funcs.detect.
> +	 *
> +	 * To avoid races against concurrent connector state updates, the
> +	 * helper libraries always call this with ctx set to a valid context,
> +	 * and &drm_mode_config.connection_mutex will always be locked with
> +	 * the ctx parameter set to this ctx. This allows taking additional
> +	 * locks as required.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * &drm_connector_status indicating the connector's status,
> +	 * or the error code returned by drm_modeset_lock(), -EDEADLK.
> +	 */
> +	int (*detect_ctx)(struct drm_connector *connector,
> +			  struct drm_modeset_acquire_ctx *ctx,
> +			  bool force);
> +
> +	/**
> +	 * @mode_valid:
> +	 *
> +	 * Callback to validate a mode for a connector, irrespective of the
> +	 * specific display configuration.
> +	 *
> +	 * This callback is used by the probe helpers to filter the mode list
> +	 * (which is usually derived from the EDID data block from the sink).
> +	 * See e.g. drm_helper_probe_single_connector_modes().
> +	 *
> +	 * This function is optional.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * This only filters the mode list supplied to userspace in the
> +	 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid,
> +	 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid,
> +	 * which are also called by the atomic helpers from
> +	 * drm_atomic_helper_check_modeset(). This allows userspace to force and
> +	 * ignore sink constraint (like the pixel clock limits in the screen's
> +	 * EDID), which is useful for e.g. testing, or working around a broken
> +	 * EDID. Any source hardware constraint (which always need to be
> +	 * enforced) therefore should be checked in one of the above callbacks,
> +	 * and not this one here.
> +	 *
> +	 * To avoid races with concurrent connector state updates, the helper
> +	 * libraries always call this with the &drm_mode_config.connection_mutex
> +	 * held. Because of this it's safe to inspect &drm_connector->state.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum
> +	 * drm_mode_status.
> +	 */
> +	enum drm_mode_status (*mode_valid)(struct drm_connector *connector,
> +					   struct drm_display_mode *mode);
> +
> +	/**
> +	 * @mode_valid_ctx:
> +	 *
> +	 * Callback to validate a mode for a connector, irrespective of the
> +	 * specific display configuration.
> +	 *
> +	 * This callback is used by the probe helpers to filter the mode list
> +	 * (which is usually derived from the EDID data block from the sink).
> +	 * See e.g. drm_helper_probe_single_connector_modes().
> +	 *
> +	 * This function is optional, and is the atomic version of
> +	 * &drm_connector_helper_funcs.mode_valid.
> +	 *
> +	 * To allow for accessing the atomic state of modesetting objects, the
> +	 * helper libraries always call this with ctx set to a valid context,
> +	 * and &drm_mode_config.connection_mutex will always be locked with
> +	 * the ctx parameter set to @ctx. This allows for taking additional
> +	 * locks as required.
> +	 *
> +	 * Even though additional locks may be acquired, this callback is
> +	 * still expected not to take any constraints into account which would
> +	 * be influenced by the currently set display state - such constraints
> +	 * should be handled in the driver's atomic check. For example, if a
> +	 * connector shares display bandwidth with other connectors then it
> +	 * would be ok to validate the minimum bandwidth requirement of a mode
> +	 * against the maximum possible bandwidth of the connector. But it
> +	 * wouldn't be ok to take the current bandwidth usage of other
> +	 * connectors into account, as this would change depending on the
> +	 * display state.
> +	 *
> +	 * Returns:
> +	 * 0 if &drm_connector_helper_funcs.mode_valid_ctx succeeded and wrote
> +	 * the &enum drm_mode_status value to @status, or a negative error
> +	 * code otherwise.
> +	 *
> +	 */
> +	int (*mode_valid_ctx)(struct drm_connector *connector,
> +			      struct drm_display_mode *mode,
> +			      struct drm_modeset_acquire_ctx *ctx,
> +			      enum drm_mode_status *status);
> +
> +	/**
> +	 * @best_encoder:
> +	 *
> +	 * This function should select the best encoder for the given connector.
> +	 *
> +	 * This function is used by both the atomic helpers (in the
> +	 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC
> +	 * helpers.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * In atomic drivers this function is called in the check phase of an
> +	 * atomic update. The driver is not allowed to change or inspect
> +	 * anything outside of arguments passed-in. Atomic drivers which need to
> +	 * inspect dynamic configuration state should instead use
> +	 * @atomic_best_encoder.
> +	 *
> +	 * You can leave this function to NULL if the connector is only
> +	 * attached to a single encoder. In this case, the core will call
> +	 * drm_connector_get_single_encoder() for you.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * Encoder that should be used for the given connector and connector
> +	 * state, or NULL if no suitable encoder exists. Note that the helpers
> +	 * will ensure that encoders aren't used twice, drivers should not check
> +	 * for this.
> +	 */
> +	struct drm_encoder *(*best_encoder)(struct drm_connector *connector);
> +
> +	/**
> +	 * @atomic_best_encoder:
> +	 *
> +	 * This is the atomic version of @best_encoder for atomic drivers which
> +	 * need to select the best encoder depending upon the desired
> +	 * configuration and can't select it statically.
> +	 *
> +	 * This function is used by drm_atomic_helper_check_modeset().
> +	 * If it is not implemented, the core will fallback to @best_encoder
> +	 * (or drm_connector_get_single_encoder() if @best_encoder is NULL).
> +	 *
> +	 * NOTE:
> +	 *
> +	 * This function is called in the check phase of an atomic update. The
> +	 * driver is not allowed to change anything outside of the
> +	 * &drm_atomic_state update tracking structure passed in.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * Encoder that should be used for the given connector and connector
> +	 * state, or NULL if no suitable encoder exists. Note that the helpers
> +	 * will ensure that encoders aren't used twice, drivers should not check
> +	 * for this.
> +	 */
> +	struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector,
> +						   struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_check:
> +	 *
> +	 * This hook is used to validate connector state. This function is
> +	 * called from &drm_atomic_helper_check_modeset, and is called when
> +	 * a connector property is set, or a modeset on the crtc is forced.
> +	 *
> +	 * Because &drm_atomic_helper_check_modeset may be called multiple times,
> +	 * this function should handle being called multiple times as well.
> +	 *
> +	 * This function is also allowed to inspect any other object's state and
> +	 * can add more state objects to the atomic commit if needed. Care must
> +	 * be taken though to ensure that state check and compute functions for
> +	 * these added states are all called, and derived state in other objects
> +	 * all updated. Again the recommendation is to just call check helpers
> +	 * until a maximal configuration is reached.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * This function is called in the check phase of an atomic update. The
> +	 * driver is not allowed to change anything outside of the free-standing
> +	 * state objects passed-in or assembled in the overall &drm_atomic_state
> +	 * update tracking structure.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * 0 on success, -EINVAL if the state or the transition can't be
> +	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
> +	 * attempt to obtain another state object ran into a &drm_modeset_lock
> +	 * deadlock.
> +	 */
> +	int (*atomic_check)(struct drm_connector *connector,
> +			    struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_commit:
> +	 *
> +	 * This hook is to be used by drivers implementing writeback connectors
> +	 * that need a point when to commit the writeback job to the hardware.
> +	 * The writeback_job to commit is available in the new connector state,
> +	 * in &drm_connector_state.writeback_job.
> +	 *
> +	 * This hook is optional.
> +	 *
> +	 * This callback is used by the atomic modeset helpers.
> +	 */
> +	void (*atomic_commit)(struct drm_connector *connector,
> +			      struct drm_atomic_state *state);
> +
> +	/**
> +	 * @prepare_writeback_job:
> +	 *
> +	 * As writeback jobs contain a framebuffer, drivers may need to
> +	 * prepare and clean them up the same way they can prepare and
> +	 * clean up framebuffers for planes. This optional connector operation
> +	 * is used to support the preparation of writeback jobs. The job
> +	 * prepare operation is called from drm_atomic_helper_prepare_planes()
> +	 * for struct &drm_writeback_connector connectors only.
> +	 *
> +	 * This operation is optional.
> +	 *
> +	 * This callback is used by the atomic modeset helpers.
> +	 */
> +	int (*prepare_writeback_job)(struct drm_writeback_connector *connector,
> +				     struct drm_writeback_job *job);
> +	/**
> +	 * @cleanup_writeback_job:
> +	 *
> +	 * This optional connector operation is used to support the
> +	 * cleanup of writeback jobs. The job cleanup operation is called
> +	 * from the existing drm_writeback_cleanup_job() function, invoked
> +	 * both when destroying the job as part of an aborted commit, or when
> +	 * the job completes.
> +	 *
> +	 * This operation is optional.
> +	 *
> +	 * This callback is used by the atomic modeset helpers.
> +	 */
> +	void (*cleanup_writeback_job)(struct drm_writeback_connector *connector,
> +				      struct drm_writeback_job *job);
> +
> +	/**
> +	 * @enable_hpd:
> +	 *
> +	 * Enable hot-plug detection for the connector.
> +	 *
> +	 * This operation is optional.
> +	 *
> +	 * This callback is used by the drm_kms_helper_poll_enable() helpers.
> +	 */
> +	void (*enable_hpd)(struct drm_connector *connector);
> +
> +	/**
> +	 * @disable_hpd:
> +	 *
> +	 * Disable hot-plug detection for the connector.
> +	 *
> +	 * This operation is optional.
> +	 *
> +	 * This callback is used by the drm_kms_helper_poll_disable() helpers.
> +	 */
> +	void (*disable_hpd)(struct drm_connector *connector);
> +};
> +
> +/**
> + * drm_connector_helper_add - sets the helper vtable for a connector
> + * @connector: DRM connector
> + * @funcs: helper vtable to set for @connector
> + */
> +static inline void drm_connector_helper_add(struct drm_connector *connector,
> +					    const struct drm_connector_helper_funcs *funcs)
> +{
> +	connector->helper_private = funcs;
> +}
> +
> +#endif /* __DRM_CONNECTOR_HELPER_VTABLE_H__ */
> diff --git a/include/drm/drm_crtc_helper_vtable.h b/include/drm/drm_crtc_helper_vtable.h
> new file mode 100644
> index 0000000000000000..6dc5d4d7af494a1b
> --- /dev/null
> +++ b/include/drm/drm_crtc_helper_vtable.h
> @@ -0,0 +1,483 @@
> +/*
> + * Copyright © 2006 Keith Packard
> + * Copyright © 2007-2008 Dave Airlie
> + * Copyright © 2007-2008 Intel Corporation
> + *   Jesse Barnes <jesse.barnes@intel.com>
> + * Copyright © 2011-2013 Intel Corporation
> + * Copyright © 2015 Intel Corporation
> + *   Daniel Vetter <daniel.vetter@ffwll.ch>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + */
> +
> +#ifndef __DRM_CRTC_HELPER_VTABLE_H__
> +#define __DRM_CRTC_HELPER_VTABLE_H__
> +
> +enum mode_set_atomic {
> +	LEAVE_ATOMIC_MODE_SET,
> +	ENTER_ATOMIC_MODE_SET,
> +};
> +
> +/**
> + * struct drm_crtc_helper_funcs - helper operations for CRTCs
> + *
> + * These hooks are used by the legacy CRTC helpers and the new atomic
> + * modesetting helpers.
> + */
> +struct drm_crtc_helper_funcs {
> +	/**
> +	 * @dpms:
> +	 *
> +	 * Callback to control power levels on the CRTC.  If the mode passed in
> +	 * is unsupported, the provider must use the next lowest power level.
> +	 * This is used by the legacy CRTC helpers to implement DPMS
> +	 * functionality in drm_helper_connector_dpms().
> +	 *
> +	 * This callback is also used to disable a CRTC by calling it with
> +	 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
> +	 *
> +	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> +	 * also support using this hook for enabling and disabling a CRTC to
> +	 * facilitate transitions to atomic, but it is deprecated. Instead
> +	 * @atomic_enable and @atomic_disable should be used.
> +	 */
> +	void (*dpms)(struct drm_crtc *crtc, int mode);
> +
> +	/**
> +	 * @prepare:
> +	 *
> +	 * This callback should prepare the CRTC for a subsequent modeset, which
> +	 * in practice means the driver should disable the CRTC if it is
> +	 * running. Most drivers ended up implementing this by calling their
> +	 * @dpms hook with DRM_MODE_DPMS_OFF.
> +	 *
> +	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> +	 * also support using this hook for disabling a CRTC to facilitate
> +	 * transitions to atomic, but it is deprecated. Instead @atomic_disable
> +	 * should be used.
> +	 */
> +	void (*prepare)(struct drm_crtc *crtc);
> +
> +	/**
> +	 * @commit:
> +	 *
> +	 * This callback should commit the new mode on the CRTC after a modeset,
> +	 * which in practice means the driver should enable the CRTC.  Most
> +	 * drivers ended up implementing this by calling their @dpms hook with
> +	 * DRM_MODE_DPMS_ON.
> +	 *
> +	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> +	 * also support using this hook for enabling a CRTC to facilitate
> +	 * transitions to atomic, but it is deprecated. Instead @atomic_enable
> +	 * should be used.
> +	 */
> +	void (*commit)(struct drm_crtc *crtc);
> +
> +	/**
> +	 * @mode_valid:
> +	 *
> +	 * This callback is used to check if a specific mode is valid in this
> +	 * crtc. This should be implemented if the crtc has some sort of
> +	 * restriction in the modes it can display. For example, a given crtc
> +	 * may be responsible to set a clock value. If the clock can not
> +	 * produce all the values for the available modes then this callback
> +	 * can be used to restrict the number of modes to only the ones that
> +	 * can be displayed.
> +	 *
> +	 * This hook is used by the probe helpers to filter the mode list in
> +	 * drm_helper_probe_single_connector_modes(), and it is used by the
> +	 * atomic helpers to validate modes supplied by userspace in
> +	 * drm_atomic_helper_check_modeset().
> +	 *
> +	 * This function is optional.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * Since this function is both called from the check phase of an atomic
> +	 * commit, and the mode validation in the probe paths it is not allowed
> +	 * to look at anything else but the passed-in mode, and validate it
> +	 * against configuration-invariant hardware constraints. Any further
> +	 * limits which depend upon the configuration can only be checked in
> +	 * @mode_fixup or @atomic_check.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * drm_mode_status Enum
> +	 */
> +	enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc,
> +					   const struct drm_display_mode *mode);
> +
> +	/**
> +	 * @mode_fixup:
> +	 *
> +	 * This callback is used to validate a mode. The parameter mode is the
> +	 * display mode that userspace requested, adjusted_mode is the mode the
> +	 * encoders need to be fed with. Note that this is the inverse semantics
> +	 * of the meaning for the &drm_encoder and &drm_bridge_funcs.mode_fixup
> +	 * vfunc. If the CRTC cannot support the requested conversion from mode
> +	 * to adjusted_mode it should reject the modeset. See also
> +	 * &drm_crtc_state.adjusted_mode for more details.
> +	 *
> +	 * This function is used by both legacy CRTC helpers and atomic helpers.
> +	 * With atomic helpers it is optional.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * This function is called in the check phase of atomic modesets, which
> +	 * can be aborted for any reason (including on userspace's request to
> +	 * just check whether a configuration would be possible). Atomic drivers
> +	 * MUST NOT touch any persistent state (hardware or software) or data
> +	 * structures except the passed in adjusted_mode parameter.
> +	 *
> +	 * This is in contrast to the legacy CRTC helpers where this was
> +	 * allowed.
> +	 *
> +	 * Atomic drivers which need to inspect and adjust more state should
> +	 * instead use the @atomic_check callback, but note that they're not
> +	 * perfectly equivalent: @mode_valid is called from
> +	 * drm_atomic_helper_check_modeset(), but @atomic_check is called from
> +	 * drm_atomic_helper_check_planes(), because originally it was meant for
> +	 * plane update checks only.
> +	 *
> +	 * Also beware that userspace can request its own custom modes, neither
> +	 * core nor helpers filter modes to the list of probe modes reported by
> +	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
> +	 * that modes are filtered consistently put any CRTC constraints and
> +	 * limits checks into @mode_valid.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * True if an acceptable configuration is possible, false if the modeset
> +	 * operation should be rejected.
> +	 */
> +	bool (*mode_fixup)(struct drm_crtc *crtc,
> +			   const struct drm_display_mode *mode,
> +			   struct drm_display_mode *adjusted_mode);
> +
> +	/**
> +	 * @mode_set:
> +	 *
> +	 * This callback is used by the legacy CRTC helpers to set a new mode,
> +	 * position and framebuffer. Since it ties the primary plane to every
> +	 * mode change it is incompatible with universal plane support. And
> +	 * since it can't update other planes it's incompatible with atomic
> +	 * modeset support.
> +	 *
> +	 * This callback is only used by CRTC helpers and deprecated.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * 0 on success or a negative error code on failure.
> +	 */
> +	int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode,
> +			struct drm_display_mode *adjusted_mode, int x, int y,
> +			struct drm_framebuffer *old_fb);
> +
> +	/**
> +	 * @mode_set_nofb:
> +	 *
> +	 * This callback is used to update the display mode of a CRTC without
> +	 * changing anything of the primary plane configuration. This fits the
> +	 * requirement of atomic and hence is used by the atomic helpers.
> +	 *
> +	 * Note that the display pipe is completely off when this function is
> +	 * called. Atomic drivers which need hardware to be running before they
> +	 * program the new display mode (e.g. because they implement runtime PM)
> +	 * should not use this hook. This is because the helper library calls
> +	 * this hook only once per mode change and not every time the display
> +	 * pipeline is suspended using either DPMS or the new "ACTIVE" property.
> +	 * Which means register values set in this callback might get reset when
> +	 * the CRTC is suspended, but not restored.  Such drivers should instead
> +	 * move all their CRTC setup into the @atomic_enable callback.
> +	 *
> +	 * This callback is optional.
> +	 */
> +	void (*mode_set_nofb)(struct drm_crtc *crtc);
> +
> +	/**
> +	 * @mode_set_base:
> +	 *
> +	 * This callback is used by the legacy CRTC helpers to set a new
> +	 * framebuffer and scanout position. It is optional and used as an
> +	 * optimized fast-path instead of a full mode set operation with all the
> +	 * resulting flickering. If it is not present
> +	 * drm_crtc_helper_set_config() will fall back to a full modeset, using
> +	 * the @mode_set callback. Since it can't update other planes it's
> +	 * incompatible with atomic modeset support.
> +	 *
> +	 * This callback is only used by the CRTC helpers and deprecated.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * 0 on success or a negative error code on failure.
> +	 */
> +	int (*mode_set_base)(struct drm_crtc *crtc, int x, int y,
> +			     struct drm_framebuffer *old_fb);
> +
> +	/**
> +	 * @mode_set_base_atomic:
> +	 *
> +	 * This callback is used by the fbdev helpers to set a new framebuffer
> +	 * and scanout without sleeping, i.e. from an atomic calling context. It
> +	 * is only used to implement kgdb support.
> +	 *
> +	 * This callback is optional and only needed for kgdb support in the fbdev
> +	 * helpers.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * 0 on success or a negative error code on failure.
> +	 */
> +	int (*mode_set_base_atomic)(struct drm_crtc *crtc,
> +				    struct drm_framebuffer *fb, int x, int y,
> +				    enum mode_set_atomic);
> +
> +	/**
> +	 * @disable:
> +	 *
> +	 * This callback should be used to disable the CRTC. With the atomic
> +	 * drivers it is called after all encoders connected to this CRTC have
> +	 * been shut off already using their own
> +	 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
> +	 * simple drivers can just add their own hooks and call it from this
> +	 * CRTC callback here by looping over all encoders connected to it using
> +	 * for_each_encoder_on_crtc().
> +	 *
> +	 * This hook is used both by legacy CRTC helpers and atomic helpers.
> +	 * Atomic drivers don't need to implement it if there's no need to
> +	 * disable anything at the CRTC level. To ensure that runtime PM
> +	 * handling (using either DPMS or the new "ACTIVE" property) works
> +	 * @disable must be the inverse of @atomic_enable for atomic drivers.
> +	 * Atomic drivers should consider to use @atomic_disable instead of
> +	 * this one.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * With legacy CRTC helpers there's a big semantic difference between
> +	 * @disable and other hooks (like @prepare or @dpms) used to shut down a
> +	 * CRTC: @disable is only called when also logically disabling the
> +	 * display pipeline and needs to release any resources acquired in
> +	 * @mode_set (like shared PLLs, or again release pinned framebuffers).
> +	 *
> +	 * Therefore @disable must be the inverse of @mode_set plus @commit for
> +	 * drivers still using legacy CRTC helpers, which is different from the
> +	 * rules under atomic.
> +	 */
> +	void (*disable)(struct drm_crtc *crtc);
> +
> +	/**
> +	 * @atomic_check:
> +	 *
> +	 * Drivers should check plane-update related CRTC constraints in this
> +	 * hook. They can also check mode related limitations but need to be
> +	 * aware of the calling order, since this hook is used by
> +	 * drm_atomic_helper_check_planes() whereas the preparations needed to
> +	 * check output routing and the display mode is done in
> +	 * drm_atomic_helper_check_modeset(). Therefore drivers that want to
> +	 * check output routing and display mode constraints in this callback
> +	 * must ensure that drm_atomic_helper_check_modeset() has been called
> +	 * beforehand. This is calling order used by the default helper
> +	 * implementation in drm_atomic_helper_check().
> +	 *
> +	 * When using drm_atomic_helper_check_planes() this hook is called
> +	 * after the &drm_plane_helper_funcs.atomic_check hook for planes, which
> +	 * allows drivers to assign shared resources requested by planes in this
> +	 * callback here. For more complicated dependencies the driver can call
> +	 * the provided check helpers multiple times until the computed state
> +	 * has a final configuration and everything has been checked.
> +	 *
> +	 * This function is also allowed to inspect any other object's state and
> +	 * can add more state objects to the atomic commit if needed. Care must
> +	 * be taken though to ensure that state check and compute functions for
> +	 * these added states are all called, and derived state in other objects
> +	 * all updated. Again the recommendation is to just call check helpers
> +	 * until a maximal configuration is reached.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is
> +	 * optional.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * This function is called in the check phase of an atomic update. The
> +	 * driver is not allowed to change anything outside of the free-standing
> +	 * state object passed-in.
> +	 *
> +	 * Also beware that userspace can request its own custom modes, neither
> +	 * core nor helpers filter modes to the list of probe modes reported by
> +	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
> +	 * that modes are filtered consistently put any CRTC constraints and
> +	 * limits checks into @mode_valid.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * 0 on success, -EINVAL if the state or the transition can't be
> +	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
> +	 * attempt to obtain another state object ran into a &drm_modeset_lock
> +	 * deadlock.
> +	 */
> +	int (*atomic_check)(struct drm_crtc *crtc,
> +			    struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_begin:
> +	 *
> +	 * Drivers should prepare for an atomic update of multiple planes on
> +	 * a CRTC in this hook. Depending upon hardware this might be vblank
> +	 * evasion, blocking updates by setting bits or doing preparatory work
> +	 * for e.g. manual update display.
> +	 *
> +	 * This hook is called before any plane commit functions are called.
> +	 *
> +	 * Note that the power state of the display pipe when this function is
> +	 * called depends upon the exact helpers and calling sequence the driver
> +	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> +	 * the tradeoffs and variants of plane commit helpers.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is
> +	 * optional.
> +	 */
> +	void (*atomic_begin)(struct drm_crtc *crtc,
> +			     struct drm_atomic_state *state);
> +	/**
> +	 * @atomic_flush:
> +	 *
> +	 * Drivers should finalize an atomic update of multiple planes on
> +	 * a CRTC in this hook. Depending upon hardware this might include
> +	 * checking that vblank evasion was successful, unblocking updates by
> +	 * setting bits or setting the GO bit to flush out all updates.
> +	 *
> +	 * Simple hardware or hardware with special requirements can commit and
> +	 * flush out all updates for all planes from this hook and forgo all the
> +	 * other commit hooks for plane updates.
> +	 *
> +	 * This hook is called after any plane commit functions are called.
> +	 *
> +	 * Note that the power state of the display pipe when this function is
> +	 * called depends upon the exact helpers and calling sequence the driver
> +	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> +	 * the tradeoffs and variants of plane commit helpers.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is
> +	 * optional.
> +	 */
> +	void (*atomic_flush)(struct drm_crtc *crtc,
> +			     struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_enable:
> +	 *
> +	 * This callback should be used to enable the CRTC. With the atomic
> +	 * drivers it is called before all encoders connected to this CRTC are
> +	 * enabled through the encoder's own &drm_encoder_helper_funcs.enable
> +	 * hook.  If that sequence is too simple drivers can just add their own
> +	 * hooks and call it from this CRTC callback here by looping over all
> +	 * encoders connected to it using for_each_encoder_on_crtc().
> +	 *
> +	 * This hook is used only by atomic helpers, for symmetry with
> +	 * @atomic_disable. Atomic drivers don't need to implement it if there's
> +	 * no need to enable anything at the CRTC level. To ensure that runtime
> +	 * PM handling (using either DPMS or the new "ACTIVE" property) works
> +	 * @atomic_enable must be the inverse of @atomic_disable for atomic
> +	 * drivers.
> +	 *
> +	 * This function is optional.
> +	 */
> +	void (*atomic_enable)(struct drm_crtc *crtc,
> +			      struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_disable:
> +	 *
> +	 * This callback should be used to disable the CRTC. With the atomic
> +	 * drivers it is called after all encoders connected to this CRTC have
> +	 * been shut off already using their own
> +	 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
> +	 * simple drivers can just add their own hooks and call it from this
> +	 * CRTC callback here by looping over all encoders connected to it using
> +	 * for_each_encoder_on_crtc().
> +	 *
> +	 * This hook is used only by atomic helpers. Atomic drivers don't
> +	 * need to implement it if there's no need to disable anything at the
> +	 * CRTC level.
> +	 *
> +	 * This function is optional.
> +	 */
> +	void (*atomic_disable)(struct drm_crtc *crtc,
> +			       struct drm_atomic_state *state);
> +
> +	/**
> +	 * @get_scanout_position:
> +	 *
> +	 * Called by vblank timestamping code.
> +	 *
> +	 * Returns the current display scanout position from a CRTC and an
> +	 * optional accurate ktime_get() timestamp of when the position was
> +	 * measured. Note that this is a helper callback which is only used
> +	 * if a driver uses drm_crtc_vblank_helper_get_vblank_timestamp()
> +	 * for the @drm_crtc_funcs.get_vblank_timestamp callback.
> +	 *
> +	 * Parameters:
> +	 *
> +	 * crtc:
> +	 *     The CRTC.
> +	 * in_vblank_irq:
> +	 *     True when called from drm_crtc_handle_vblank(). Some drivers
> +	 *     need to apply some workarounds for gpu-specific vblank irq
> +	 *     quirks if the flag is set.
> +	 * vpos:
> +	 *     Target location for current vertical scanout position.
> +	 * hpos:
> +	 *     Target location for current horizontal scanout position.
> +	 * stime:
> +	 *     Target location for timestamp taken immediately before
> +	 *     scanout position query. Can be NULL to skip timestamp.
> +	 * etime:
> +	 *     Target location for timestamp taken immediately after
> +	 *     scanout position query. Can be NULL to skip timestamp.
> +	 * mode:
> +	 *     Current display timings.
> +	 *
> +	 * Returns vpos as a positive number while in active scanout area.
> +	 * Returns vpos as a negative number inside vblank, counting the number
> +	 * of scanlines to go until end of vblank, e.g., -1 means "one scanline
> +	 * until start of active scanout / end of vblank."
> +	 *
> +	 * Returns:
> +	 *
> +	 * True on success, false if a reliable scanout position counter could
> +	 * not be read out.
> +	 */
> +	bool (*get_scanout_position)(struct drm_crtc *crtc,
> +				     bool in_vblank_irq, int *vpos, int *hpos,
> +				     ktime_t *stime, ktime_t *etime,
> +				     const struct drm_display_mode *mode);
> +};
> +
> +/**
> + * drm_crtc_helper_add - sets the helper vtable for a crtc
> + * @crtc: DRM CRTC
> + * @funcs: helper vtable to set for @crtc
> + */
> +static inline void drm_crtc_helper_add(struct drm_crtc *crtc,
> +				       const struct drm_crtc_helper_funcs *funcs)
> +{
> +	crtc->helper_private = funcs;
> +}
> +
> +#endif /* __DRM_CRTC_HELPER_VTABLE_H__ */
> diff --git a/include/drm/drm_encoder_helper_vtable.h b/include/drm/drm_encoder_helper_vtable.h
> new file mode 100644
> index 0000000000000000..434de1ebb829f3ed
> --- /dev/null
> +++ b/include/drm/drm_encoder_helper_vtable.h
> @@ -0,0 +1,381 @@
> +/*
> + * Copyright © 2006 Keith Packard
> + * Copyright © 2007-2008 Dave Airlie
> + * Copyright © 2007-2008 Intel Corporation
> + *   Jesse Barnes <jesse.barnes@intel.com>
> + * Copyright © 2011-2013 Intel Corporation
> + * Copyright © 2015 Intel Corporation
> + *   Daniel Vetter <daniel.vetter@ffwll.ch>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + */
> +
> +#ifndef __DRM_ENCODER_HELPER_VTABLE_H__
> +#define __DRM_ENCODER_HELPER_VTABLE_H__
> +
> +/**
> + * struct drm_encoder_helper_funcs - helper operations for encoders
> + *
> + * These hooks are used by the legacy CRTC helpers and the new atomic
> + * modesetting helpers.
> + */
> +struct drm_encoder_helper_funcs {
> +	/**
> +	 * @dpms:
> +	 *
> +	 * Callback to control power levels on the encoder.  If the mode passed in
> +	 * is unsupported, the provider must use the next lowest power level.
> +	 * This is used by the legacy encoder helpers to implement DPMS
> +	 * functionality in drm_helper_connector_dpms().
> +	 *
> +	 * This callback is also used to disable an encoder by calling it with
> +	 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
> +	 *
> +	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> +	 * also support using this hook for enabling and disabling an encoder to
> +	 * facilitate transitions to atomic, but it is deprecated. Instead
> +	 * @enable and @disable should be used.
> +	 */
> +	void (*dpms)(struct drm_encoder *encoder, int mode);
> +
> +	/**
> +	 * @mode_valid:
> +	 *
> +	 * This callback is used to check if a specific mode is valid in this
> +	 * encoder. This should be implemented if the encoder has some sort
> +	 * of restriction in the modes it can display. For example, a given
> +	 * encoder may be responsible to set a clock value. If the clock can
> +	 * not produce all the values for the available modes then this callback
> +	 * can be used to restrict the number of modes to only the ones that
> +	 * can be displayed.
> +	 *
> +	 * This hook is used by the probe helpers to filter the mode list in
> +	 * drm_helper_probe_single_connector_modes(), and it is used by the
> +	 * atomic helpers to validate modes supplied by userspace in
> +	 * drm_atomic_helper_check_modeset().
> +	 *
> +	 * This function is optional.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * Since this function is both called from the check phase of an atomic
> +	 * commit, and the mode validation in the probe paths it is not allowed
> +	 * to look at anything else but the passed-in mode, and validate it
> +	 * against configuration-invariant hardware constraints. Any further
> +	 * limits which depend upon the configuration can only be checked in
> +	 * @mode_fixup or @atomic_check.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * drm_mode_status Enum
> +	 */
> +	enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc,
> +					   const struct drm_display_mode *mode);
> +
> +	/**
> +	 * @mode_fixup:
> +	 *
> +	 * This callback is used to validate and adjust a mode. The parameter
> +	 * mode is the display mode that should be fed to the next element in
> +	 * the display chain, either the final &drm_connector or a &drm_bridge.
> +	 * The parameter adjusted_mode is the input mode the encoder requires. It
> +	 * can be modified by this callback and does not need to match mode. See
> +	 * also &drm_crtc_state.adjusted_mode for more details.
> +	 *
> +	 * This function is used by both legacy CRTC helpers and atomic helpers.
> +	 * This hook is optional.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * This function is called in the check phase of atomic modesets, which
> +	 * can be aborted for any reason (including on userspace's request to
> +	 * just check whether a configuration would be possible). Atomic drivers
> +	 * MUST NOT touch any persistent state (hardware or software) or data
> +	 * structures except the passed in adjusted_mode parameter.
> +	 *
> +	 * This is in contrast to the legacy CRTC helpers where this was
> +	 * allowed.
> +	 *
> +	 * Atomic drivers which need to inspect and adjust more state should
> +	 * instead use the @atomic_check callback. If @atomic_check is used,
> +	 * this hook isn't called since @atomic_check allows a strict superset
> +	 * of the functionality of @mode_fixup.
> +	 *
> +	 * Also beware that userspace can request its own custom modes, neither
> +	 * core nor helpers filter modes to the list of probe modes reported by
> +	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
> +	 * that modes are filtered consistently put any encoder constraints and
> +	 * limits checks into @mode_valid.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * True if an acceptable configuration is possible, false if the modeset
> +	 * operation should be rejected.
> +	 */
> +	bool (*mode_fixup)(struct drm_encoder *encoder,
> +			   const struct drm_display_mode *mode,
> +			   struct drm_display_mode *adjusted_mode);
> +
> +	/**
> +	 * @prepare:
> +	 *
> +	 * This callback should prepare the encoder for a subsequent modeset,
> +	 * which in practice means the driver should disable the encoder if it
> +	 * is running. Most drivers ended up implementing this by calling their
> +	 * @dpms hook with DRM_MODE_DPMS_OFF.
> +	 *
> +	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> +	 * also support using this hook for disabling an encoder to facilitate
> +	 * transitions to atomic, but it is deprecated. Instead @disable should
> +	 * be used.
> +	 */
> +	void (*prepare)(struct drm_encoder *encoder);
> +
> +	/**
> +	 * @commit:
> +	 *
> +	 * This callback should commit the new mode on the encoder after a modeset,
> +	 * which in practice means the driver should enable the encoder.  Most
> +	 * drivers ended up implementing this by calling their @dpms hook with
> +	 * DRM_MODE_DPMS_ON.
> +	 *
> +	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> +	 * also support using this hook for enabling an encoder to facilitate
> +	 * transitions to atomic, but it is deprecated. Instead @enable should
> +	 * be used.
> +	 */
> +	void (*commit)(struct drm_encoder *encoder);
> +
> +	/**
> +	 * @mode_set:
> +	 *
> +	 * This callback is used to update the display mode of an encoder.
> +	 *
> +	 * Note that the display pipe is completely off when this function is
> +	 * called. Drivers which need hardware to be running before they program
> +	 * the new display mode (because they implement runtime PM) should not
> +	 * use this hook, because the helper library calls it only once and not
> +	 * every time the display pipeline is suspend using either DPMS or the
> +	 * new "ACTIVE" property. Such drivers should instead move all their
> +	 * encoder setup into the @enable callback.
> +	 *
> +	 * This callback is used both by the legacy CRTC helpers and the atomic
> +	 * modeset helpers. It is optional in the atomic helpers.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * If the driver uses the atomic modeset helpers and needs to inspect
> +	 * the connector state or connector display info during mode setting,
> +	 * @atomic_mode_set can be used instead.
> +	 */
> +	void (*mode_set)(struct drm_encoder *encoder,
> +			 struct drm_display_mode *mode,
> +			 struct drm_display_mode *adjusted_mode);
> +
> +	/**
> +	 * @atomic_mode_set:
> +	 *
> +	 * This callback is used to update the display mode of an encoder.
> +	 *
> +	 * Note that the display pipe is completely off when this function is
> +	 * called. Drivers which need hardware to be running before they program
> +	 * the new display mode (because they implement runtime PM) should not
> +	 * use this hook, because the helper library calls it only once and not
> +	 * every time the display pipeline is suspended using either DPMS or the
> +	 * new "ACTIVE" property. Such drivers should instead move all their
> +	 * encoder setup into the @enable callback.
> +	 *
> +	 * This callback is used by the atomic modeset helpers in place of the
> +	 * @mode_set callback, if set by the driver. It is optional and should
> +	 * be used instead of @mode_set if the driver needs to inspect the
> +	 * connector state or display info, since there is no direct way to
> +	 * go from the encoder to the current connector.
> +	 */
> +	void (*atomic_mode_set)(struct drm_encoder *encoder,
> +				struct drm_crtc_state *crtc_state,
> +				struct drm_connector_state *conn_state);
> +
> +	/**
> +	 * @detect:
> +	 *
> +	 * This callback can be used by drivers who want to do detection on the
> +	 * encoder object instead of in connector functions.
> +	 *
> +	 * It is not used by any helper and therefore has purely driver-specific
> +	 * semantics. New drivers shouldn't use this and instead just implement
> +	 * their own private callbacks.
> +	 *
> +	 * FIXME:
> +	 *
> +	 * This should just be converted into a pile of driver vfuncs.
> +	 * Currently radeon, amdgpu and nouveau are using it.
> +	 */
> +	enum drm_connector_status (*detect)(struct drm_encoder *encoder,
> +					    struct drm_connector *connector);
> +
> +	/**
> +	 * @atomic_disable:
> +	 *
> +	 * This callback should be used to disable the encoder. With the atomic
> +	 * drivers it is called before this encoder's CRTC has been shut off
> +	 * using their own &drm_crtc_helper_funcs.atomic_disable hook. If that
> +	 * sequence is too simple drivers can just add their own driver private
> +	 * encoder hooks and call them from CRTC's callback by looping over all
> +	 * encoders connected to it using for_each_encoder_on_crtc().
> +	 *
> +	 * This callback is a variant of @disable that provides the atomic state
> +	 * to the driver. If @atomic_disable is implemented, @disable is not
> +	 * called by the helpers.
> +	 *
> +	 * This hook is only used by atomic helpers. Atomic drivers don't need
> +	 * to implement it if there's no need to disable anything at the encoder
> +	 * level. To ensure that runtime PM handling (using either DPMS or the
> +	 * new "ACTIVE" property) works @atomic_disable must be the inverse of
> +	 * @atomic_enable.
> +	 */
> +	void (*atomic_disable)(struct drm_encoder *encoder,
> +			       struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_enable:
> +	 *
> +	 * This callback should be used to enable the encoder. It is called
> +	 * after this encoder's CRTC has been enabled using their own
> +	 * &drm_crtc_helper_funcs.atomic_enable hook. If that sequence is
> +	 * too simple drivers can just add their own driver private encoder
> +	 * hooks and call them from CRTC's callback by looping over all encoders
> +	 * connected to it using for_each_encoder_on_crtc().
> +	 *
> +	 * This callback is a variant of @enable that provides the atomic state
> +	 * to the driver. If @atomic_enable is implemented, @enable is not
> +	 * called by the helpers.
> +	 *
> +	 * This hook is only used by atomic helpers, it is the opposite of
> +	 * @atomic_disable. Atomic drivers don't need to implement it if there's
> +	 * no need to enable anything at the encoder level. To ensure that
> +	 * runtime PM handling works @atomic_enable must be the inverse of
> +	 * @atomic_disable.
> +	 */
> +	void (*atomic_enable)(struct drm_encoder *encoder,
> +			      struct drm_atomic_state *state);
> +
> +	/**
> +	 * @disable:
> +	 *
> +	 * This callback should be used to disable the encoder. With the atomic
> +	 * drivers it is called before this encoder's CRTC has been shut off
> +	 * using their own &drm_crtc_helper_funcs.disable hook.  If that
> +	 * sequence is too simple drivers can just add their own driver private
> +	 * encoder hooks and call them from CRTC's callback by looping over all
> +	 * encoders connected to it using for_each_encoder_on_crtc().
> +	 *
> +	 * This hook is used both by legacy CRTC helpers and atomic helpers.
> +	 * Atomic drivers don't need to implement it if there's no need to
> +	 * disable anything at the encoder level. To ensure that runtime PM
> +	 * handling (using either DPMS or the new "ACTIVE" property) works
> +	 * @disable must be the inverse of @enable for atomic drivers.
> +	 *
> +	 * For atomic drivers also consider @atomic_disable and save yourself
> +	 * from having to read the NOTE below!
> +	 *
> +	 * NOTE:
> +	 *
> +	 * With legacy CRTC helpers there's a big semantic difference between
> +	 * @disable and other hooks (like @prepare or @dpms) used to shut down a
> +	 * encoder: @disable is only called when also logically disabling the
> +	 * display pipeline and needs to release any resources acquired in
> +	 * @mode_set (like shared PLLs, or again release pinned framebuffers).
> +	 *
> +	 * Therefore @disable must be the inverse of @mode_set plus @commit for
> +	 * drivers still using legacy CRTC helpers, which is different from the
> +	 * rules under atomic.
> +	 */
> +	void (*disable)(struct drm_encoder *encoder);
> +
> +	/**
> +	 * @enable:
> +	 *
> +	 * This callback should be used to enable the encoder. With the atomic
> +	 * drivers it is called after this encoder's CRTC has been enabled using
> +	 * their own &drm_crtc_helper_funcs.enable hook.  If that sequence is
> +	 * too simple drivers can just add their own driver private encoder
> +	 * hooks and call them from CRTC's callback by looping over all encoders
> +	 * connected to it using for_each_encoder_on_crtc().
> +	 *
> +	 * This hook is only used by atomic helpers, it is the opposite of
> +	 * @disable. Atomic drivers don't need to implement it if there's no
> +	 * need to enable anything at the encoder level. To ensure that
> +	 * runtime PM handling (using either DPMS or the new "ACTIVE" property)
> +	 * works @enable must be the inverse of @disable for atomic drivers.
> +	 */
> +	void (*enable)(struct drm_encoder *encoder);
> +
> +	/**
> +	 * @atomic_check:
> +	 *
> +	 * This callback is used to validate encoder state for atomic drivers.
> +	 * Since the encoder is the object connecting the CRTC and connector it
> +	 * gets passed both states, to be able to validate interactions and
> +	 * update the CRTC to match what the encoder needs for the requested
> +	 * connector.
> +	 *
> +	 * Since this provides a strict superset of the functionality of
> +	 * @mode_fixup (the requested and adjusted modes are both available
> +	 * through the passed in &struct drm_crtc_state) @mode_fixup is not
> +	 * called when @atomic_check is implemented.
> +	 *
> +	 * This function is used by the atomic helpers, but it is optional.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * This function is called in the check phase of an atomic update. The
> +	 * driver is not allowed to change anything outside of the free-standing
> +	 * state objects passed-in or assembled in the overall &drm_atomic_state
> +	 * update tracking structure.
> +	 *
> +	 * Also beware that userspace can request its own custom modes, neither
> +	 * core nor helpers filter modes to the list of probe modes reported by
> +	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
> +	 * that modes are filtered consistently put any encoder constraints and
> +	 * limits checks into @mode_valid.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * 0 on success, -EINVAL if the state or the transition can't be
> +	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
> +	 * attempt to obtain another state object ran into a &drm_modeset_lock
> +	 * deadlock.
> +	 */
> +	int (*atomic_check)(struct drm_encoder *encoder,
> +			    struct drm_crtc_state *crtc_state,
> +			    struct drm_connector_state *conn_state);
> +};
> +
> +/**
> + * drm_encoder_helper_add - sets the helper vtable for an encoder
> + * @encoder: DRM encoder
> + * @funcs: helper vtable to set for @encoder
> + */
> +static inline void drm_encoder_helper_add(struct drm_encoder *encoder,
> +					  const struct drm_encoder_helper_funcs *funcs)
> +{
> +	encoder->helper_private = funcs;
> +}
> +
> +#endif /* __DRM_ENCODER_HELPER_VTABLE_H__ */
> diff --git a/include/drm/drm_mode_config_helper_vtable.h b/include/drm/drm_mode_config_helper_vtable.h
> new file mode 100644
> index 0000000000000000..a56e3490e27411de
> --- /dev/null
> +++ b/include/drm/drm_mode_config_helper_vtable.h
> @@ -0,0 +1,97 @@
> +/*
> + * Copyright © 2006 Keith Packard
> + * Copyright © 2007-2008 Dave Airlie
> + * Copyright © 2007-2008 Intel Corporation
> + *   Jesse Barnes <jesse.barnes@intel.com>
> + * Copyright © 2011-2013 Intel Corporation
> + * Copyright © 2015 Intel Corporation
> + *   Daniel Vetter <daniel.vetter@ffwll.ch>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + */
> +
> +#ifndef __DRM_MODE_CONFIG_HELPER_VTABLE_H__
> +#define __DRM_MODE_CONFIG_HELPER_VTABLE_H__
> +
> +/**
> + * struct drm_mode_config_helper_funcs - global modeset helper operations
> + *
> + * These helper functions are used by the atomic helpers.
> + */
> +struct drm_mode_config_helper_funcs {
> +	/**
> +	 * @atomic_commit_tail:
> +	 *
> +	 * This hook is used by the default atomic_commit() hook implemented in
> +	 * drm_atomic_helper_commit() together with the nonblocking commit
> +	 * helpers (see drm_atomic_helper_setup_commit() for a starting point)
> +	 * to implement blocking and nonblocking commits easily. It is not used
> +	 * by the atomic helpers
> +	 *
> +	 * This function is called when the new atomic state has already been
> +	 * swapped into the various state pointers. The passed in state
> +	 * therefore contains copies of the old/previous state. This hook should
> +	 * commit the new state into hardware. Note that the helpers have
> +	 * already waited for preceding atomic commits and fences, but drivers
> +	 * can add more waiting calls at the start of their implementation, e.g.
> +	 * to wait for driver-internal request for implicit syncing, before
> +	 * starting to commit the update to the hardware.
> +	 *
> +	 * After the atomic update is committed to the hardware this hook needs
> +	 * to call drm_atomic_helper_commit_hw_done(). Then wait for the update
> +	 * to be executed by the hardware, for example using
> +	 * drm_atomic_helper_wait_for_vblanks() or
> +	 * drm_atomic_helper_wait_for_flip_done(), and then clean up the old
> +	 * framebuffers using drm_atomic_helper_cleanup_planes().
> +	 *
> +	 * When disabling a CRTC this hook _must_ stall for the commit to
> +	 * complete. Vblank waits don't work on disabled CRTC, hence the core
> +	 * can't take care of this. And it also can't rely on the vblank event,
> +	 * since that can be signalled already when the screen shows black,
> +	 * which can happen much earlier than the last hardware access needed to
> +	 * shut off the display pipeline completely.
> +	 *
> +	 * This hook is optional, the default implementation is
> +	 * drm_atomic_helper_commit_tail().
> +	 */
> +	void (*atomic_commit_tail)(struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_commit_setup:
> +	 *
> +	 * This hook is used by the default atomic_commit() hook implemented in
> +	 * drm_atomic_helper_commit() together with the nonblocking helpers (see
> +	 * drm_atomic_helper_setup_commit()) to extend the DRM commit setup. It
> +	 * is not used by the atomic helpers.
> +	 *
> +	 * This function is called at the end of
> +	 * drm_atomic_helper_setup_commit(), so once the commit has been
> +	 * properly setup across the generic DRM object states. It allows
> +	 * drivers to do some additional commit tracking that isn't related to a
> +	 * CRTC, plane or connector, tracked in a &drm_private_obj structure.
> +	 *
> +	 * Note that the documentation of &drm_private_obj has more details on
> +	 * how one should implement this.
> +	 *
> +	 * This hook is optional.
> +	 */
> +	int (*atomic_commit_setup)(struct drm_atomic_state *state);
> +};
> +
> +#endif /* __DRM_MODE_CONFIG_HELPER_VTABLE_H__ */
> diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
> index 91860372be6c064e..a9fb43b07b60872d 100644
> --- a/include/drm/drm_modeset_helper_vtables.h
> +++ b/include/drm/drm_modeset_helper_vtables.h
> @@ -48,1466 +48,10 @@
>    * To make this clear all the helper vtables are pulled together in this location here.
>    */
>   
> -struct drm_writeback_connector;
> -struct drm_writeback_job;
> -
> -enum mode_set_atomic {
> -	LEAVE_ATOMIC_MODE_SET,
> -	ENTER_ATOMIC_MODE_SET,
> -};
> -
> -/**
> - * struct drm_crtc_helper_funcs - helper operations for CRTCs
> - *
> - * These hooks are used by the legacy CRTC helpers and the new atomic
> - * modesetting helpers.
> - */
> -struct drm_crtc_helper_funcs {
> -	/**
> -	 * @dpms:
> -	 *
> -	 * Callback to control power levels on the CRTC.  If the mode passed in
> -	 * is unsupported, the provider must use the next lowest power level.
> -	 * This is used by the legacy CRTC helpers to implement DPMS
> -	 * functionality in drm_helper_connector_dpms().
> -	 *
> -	 * This callback is also used to disable a CRTC by calling it with
> -	 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
> -	 *
> -	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> -	 * also support using this hook for enabling and disabling a CRTC to
> -	 * facilitate transitions to atomic, but it is deprecated. Instead
> -	 * @atomic_enable and @atomic_disable should be used.
> -	 */
> -	void (*dpms)(struct drm_crtc *crtc, int mode);
> -
> -	/**
> -	 * @prepare:
> -	 *
> -	 * This callback should prepare the CRTC for a subsequent modeset, which
> -	 * in practice means the driver should disable the CRTC if it is
> -	 * running. Most drivers ended up implementing this by calling their
> -	 * @dpms hook with DRM_MODE_DPMS_OFF.
> -	 *
> -	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> -	 * also support using this hook for disabling a CRTC to facilitate
> -	 * transitions to atomic, but it is deprecated. Instead @atomic_disable
> -	 * should be used.
> -	 */
> -	void (*prepare)(struct drm_crtc *crtc);
> -
> -	/**
> -	 * @commit:
> -	 *
> -	 * This callback should commit the new mode on the CRTC after a modeset,
> -	 * which in practice means the driver should enable the CRTC.  Most
> -	 * drivers ended up implementing this by calling their @dpms hook with
> -	 * DRM_MODE_DPMS_ON.
> -	 *
> -	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> -	 * also support using this hook for enabling a CRTC to facilitate
> -	 * transitions to atomic, but it is deprecated. Instead @atomic_enable
> -	 * should be used.
> -	 */
> -	void (*commit)(struct drm_crtc *crtc);
> -
> -	/**
> -	 * @mode_valid:
> -	 *
> -	 * This callback is used to check if a specific mode is valid in this
> -	 * crtc. This should be implemented if the crtc has some sort of
> -	 * restriction in the modes it can display. For example, a given crtc
> -	 * may be responsible to set a clock value. If the clock can not
> -	 * produce all the values for the available modes then this callback
> -	 * can be used to restrict the number of modes to only the ones that
> -	 * can be displayed.
> -	 *
> -	 * This hook is used by the probe helpers to filter the mode list in
> -	 * drm_helper_probe_single_connector_modes(), and it is used by the
> -	 * atomic helpers to validate modes supplied by userspace in
> -	 * drm_atomic_helper_check_modeset().
> -	 *
> -	 * This function is optional.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * Since this function is both called from the check phase of an atomic
> -	 * commit, and the mode validation in the probe paths it is not allowed
> -	 * to look at anything else but the passed-in mode, and validate it
> -	 * against configuration-invariant hardware constraints. Any further
> -	 * limits which depend upon the configuration can only be checked in
> -	 * @mode_fixup or @atomic_check.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * drm_mode_status Enum
> -	 */
> -	enum drm_mode_status (*mode_valid)(struct drm_crtc *crtc,
> -					   const struct drm_display_mode *mode);
> -
> -	/**
> -	 * @mode_fixup:
> -	 *
> -	 * This callback is used to validate a mode. The parameter mode is the
> -	 * display mode that userspace requested, adjusted_mode is the mode the
> -	 * encoders need to be fed with. Note that this is the inverse semantics
> -	 * of the meaning for the &drm_encoder and &drm_bridge_funcs.mode_fixup
> -	 * vfunc. If the CRTC cannot support the requested conversion from mode
> -	 * to adjusted_mode it should reject the modeset. See also
> -	 * &drm_crtc_state.adjusted_mode for more details.
> -	 *
> -	 * This function is used by both legacy CRTC helpers and atomic helpers.
> -	 * With atomic helpers it is optional.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * This function is called in the check phase of atomic modesets, which
> -	 * can be aborted for any reason (including on userspace's request to
> -	 * just check whether a configuration would be possible). Atomic drivers
> -	 * MUST NOT touch any persistent state (hardware or software) or data
> -	 * structures except the passed in adjusted_mode parameter.
> -	 *
> -	 * This is in contrast to the legacy CRTC helpers where this was
> -	 * allowed.
> -	 *
> -	 * Atomic drivers which need to inspect and adjust more state should
> -	 * instead use the @atomic_check callback, but note that they're not
> -	 * perfectly equivalent: @mode_valid is called from
> -	 * drm_atomic_helper_check_modeset(), but @atomic_check is called from
> -	 * drm_atomic_helper_check_planes(), because originally it was meant for
> -	 * plane update checks only.
> -	 *
> -	 * Also beware that userspace can request its own custom modes, neither
> -	 * core nor helpers filter modes to the list of probe modes reported by
> -	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
> -	 * that modes are filtered consistently put any CRTC constraints and
> -	 * limits checks into @mode_valid.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * True if an acceptable configuration is possible, false if the modeset
> -	 * operation should be rejected.
> -	 */
> -	bool (*mode_fixup)(struct drm_crtc *crtc,
> -			   const struct drm_display_mode *mode,
> -			   struct drm_display_mode *adjusted_mode);
> -
> -	/**
> -	 * @mode_set:
> -	 *
> -	 * This callback is used by the legacy CRTC helpers to set a new mode,
> -	 * position and framebuffer. Since it ties the primary plane to every
> -	 * mode change it is incompatible with universal plane support. And
> -	 * since it can't update other planes it's incompatible with atomic
> -	 * modeset support.
> -	 *
> -	 * This callback is only used by CRTC helpers and deprecated.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * 0 on success or a negative error code on failure.
> -	 */
> -	int (*mode_set)(struct drm_crtc *crtc, struct drm_display_mode *mode,
> -			struct drm_display_mode *adjusted_mode, int x, int y,
> -			struct drm_framebuffer *old_fb);
> -
> -	/**
> -	 * @mode_set_nofb:
> -	 *
> -	 * This callback is used to update the display mode of a CRTC without
> -	 * changing anything of the primary plane configuration. This fits the
> -	 * requirement of atomic and hence is used by the atomic helpers.
> -	 *
> -	 * Note that the display pipe is completely off when this function is
> -	 * called. Atomic drivers which need hardware to be running before they
> -	 * program the new display mode (e.g. because they implement runtime PM)
> -	 * should not use this hook. This is because the helper library calls
> -	 * this hook only once per mode change and not every time the display
> -	 * pipeline is suspended using either DPMS or the new "ACTIVE" property.
> -	 * Which means register values set in this callback might get reset when
> -	 * the CRTC is suspended, but not restored.  Such drivers should instead
> -	 * move all their CRTC setup into the @atomic_enable callback.
> -	 *
> -	 * This callback is optional.
> -	 */
> -	void (*mode_set_nofb)(struct drm_crtc *crtc);
> -
> -	/**
> -	 * @mode_set_base:
> -	 *
> -	 * This callback is used by the legacy CRTC helpers to set a new
> -	 * framebuffer and scanout position. It is optional and used as an
> -	 * optimized fast-path instead of a full mode set operation with all the
> -	 * resulting flickering. If it is not present
> -	 * drm_crtc_helper_set_config() will fall back to a full modeset, using
> -	 * the @mode_set callback. Since it can't update other planes it's
> -	 * incompatible with atomic modeset support.
> -	 *
> -	 * This callback is only used by the CRTC helpers and deprecated.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * 0 on success or a negative error code on failure.
> -	 */
> -	int (*mode_set_base)(struct drm_crtc *crtc, int x, int y,
> -			     struct drm_framebuffer *old_fb);
> -
> -	/**
> -	 * @mode_set_base_atomic:
> -	 *
> -	 * This callback is used by the fbdev helpers to set a new framebuffer
> -	 * and scanout without sleeping, i.e. from an atomic calling context. It
> -	 * is only used to implement kgdb support.
> -	 *
> -	 * This callback is optional and only needed for kgdb support in the fbdev
> -	 * helpers.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * 0 on success or a negative error code on failure.
> -	 */
> -	int (*mode_set_base_atomic)(struct drm_crtc *crtc,
> -				    struct drm_framebuffer *fb, int x, int y,
> -				    enum mode_set_atomic);
> -
> -	/**
> -	 * @disable:
> -	 *
> -	 * This callback should be used to disable the CRTC. With the atomic
> -	 * drivers it is called after all encoders connected to this CRTC have
> -	 * been shut off already using their own
> -	 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
> -	 * simple drivers can just add their own hooks and call it from this
> -	 * CRTC callback here by looping over all encoders connected to it using
> -	 * for_each_encoder_on_crtc().
> -	 *
> -	 * This hook is used both by legacy CRTC helpers and atomic helpers.
> -	 * Atomic drivers don't need to implement it if there's no need to
> -	 * disable anything at the CRTC level. To ensure that runtime PM
> -	 * handling (using either DPMS or the new "ACTIVE" property) works
> -	 * @disable must be the inverse of @atomic_enable for atomic drivers.
> -	 * Atomic drivers should consider to use @atomic_disable instead of
> -	 * this one.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * With legacy CRTC helpers there's a big semantic difference between
> -	 * @disable and other hooks (like @prepare or @dpms) used to shut down a
> -	 * CRTC: @disable is only called when also logically disabling the
> -	 * display pipeline and needs to release any resources acquired in
> -	 * @mode_set (like shared PLLs, or again release pinned framebuffers).
> -	 *
> -	 * Therefore @disable must be the inverse of @mode_set plus @commit for
> -	 * drivers still using legacy CRTC helpers, which is different from the
> -	 * rules under atomic.
> -	 */
> -	void (*disable)(struct drm_crtc *crtc);
> -
> -	/**
> -	 * @atomic_check:
> -	 *
> -	 * Drivers should check plane-update related CRTC constraints in this
> -	 * hook. They can also check mode related limitations but need to be
> -	 * aware of the calling order, since this hook is used by
> -	 * drm_atomic_helper_check_planes() whereas the preparations needed to
> -	 * check output routing and the display mode is done in
> -	 * drm_atomic_helper_check_modeset(). Therefore drivers that want to
> -	 * check output routing and display mode constraints in this callback
> -	 * must ensure that drm_atomic_helper_check_modeset() has been called
> -	 * beforehand. This is calling order used by the default helper
> -	 * implementation in drm_atomic_helper_check().
> -	 *
> -	 * When using drm_atomic_helper_check_planes() this hook is called
> -	 * after the &drm_plane_helper_funcs.atomic_check hook for planes, which
> -	 * allows drivers to assign shared resources requested by planes in this
> -	 * callback here. For more complicated dependencies the driver can call
> -	 * the provided check helpers multiple times until the computed state
> -	 * has a final configuration and everything has been checked.
> -	 *
> -	 * This function is also allowed to inspect any other object's state and
> -	 * can add more state objects to the atomic commit if needed. Care must
> -	 * be taken though to ensure that state check and compute functions for
> -	 * these added states are all called, and derived state in other objects
> -	 * all updated. Again the recommendation is to just call check helpers
> -	 * until a maximal configuration is reached.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is
> -	 * optional.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * This function is called in the check phase of an atomic update. The
> -	 * driver is not allowed to change anything outside of the free-standing
> -	 * state object passed-in.
> -	 *
> -	 * Also beware that userspace can request its own custom modes, neither
> -	 * core nor helpers filter modes to the list of probe modes reported by
> -	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
> -	 * that modes are filtered consistently put any CRTC constraints and
> -	 * limits checks into @mode_valid.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * 0 on success, -EINVAL if the state or the transition can't be
> -	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
> -	 * attempt to obtain another state object ran into a &drm_modeset_lock
> -	 * deadlock.
> -	 */
> -	int (*atomic_check)(struct drm_crtc *crtc,
> -			    struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_begin:
> -	 *
> -	 * Drivers should prepare for an atomic update of multiple planes on
> -	 * a CRTC in this hook. Depending upon hardware this might be vblank
> -	 * evasion, blocking updates by setting bits or doing preparatory work
> -	 * for e.g. manual update display.
> -	 *
> -	 * This hook is called before any plane commit functions are called.
> -	 *
> -	 * Note that the power state of the display pipe when this function is
> -	 * called depends upon the exact helpers and calling sequence the driver
> -	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> -	 * the tradeoffs and variants of plane commit helpers.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is
> -	 * optional.
> -	 */
> -	void (*atomic_begin)(struct drm_crtc *crtc,
> -			     struct drm_atomic_state *state);
> -	/**
> -	 * @atomic_flush:
> -	 *
> -	 * Drivers should finalize an atomic update of multiple planes on
> -	 * a CRTC in this hook. Depending upon hardware this might include
> -	 * checking that vblank evasion was successful, unblocking updates by
> -	 * setting bits or setting the GO bit to flush out all updates.
> -	 *
> -	 * Simple hardware or hardware with special requirements can commit and
> -	 * flush out all updates for all planes from this hook and forgo all the
> -	 * other commit hooks for plane updates.
> -	 *
> -	 * This hook is called after any plane commit functions are called.
> -	 *
> -	 * Note that the power state of the display pipe when this function is
> -	 * called depends upon the exact helpers and calling sequence the driver
> -	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> -	 * the tradeoffs and variants of plane commit helpers.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is
> -	 * optional.
> -	 */
> -	void (*atomic_flush)(struct drm_crtc *crtc,
> -			     struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_enable:
> -	 *
> -	 * This callback should be used to enable the CRTC. With the atomic
> -	 * drivers it is called before all encoders connected to this CRTC are
> -	 * enabled through the encoder's own &drm_encoder_helper_funcs.enable
> -	 * hook.  If that sequence is too simple drivers can just add their own
> -	 * hooks and call it from this CRTC callback here by looping over all
> -	 * encoders connected to it using for_each_encoder_on_crtc().
> -	 *
> -	 * This hook is used only by atomic helpers, for symmetry with
> -	 * @atomic_disable. Atomic drivers don't need to implement it if there's
> -	 * no need to enable anything at the CRTC level. To ensure that runtime
> -	 * PM handling (using either DPMS or the new "ACTIVE" property) works
> -	 * @atomic_enable must be the inverse of @atomic_disable for atomic
> -	 * drivers.
> -	 *
> -	 * This function is optional.
> -	 */
> -	void (*atomic_enable)(struct drm_crtc *crtc,
> -			      struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_disable:
> -	 *
> -	 * This callback should be used to disable the CRTC. With the atomic
> -	 * drivers it is called after all encoders connected to this CRTC have
> -	 * been shut off already using their own
> -	 * &drm_encoder_helper_funcs.disable hook. If that sequence is too
> -	 * simple drivers can just add their own hooks and call it from this
> -	 * CRTC callback here by looping over all encoders connected to it using
> -	 * for_each_encoder_on_crtc().
> -	 *
> -	 * This hook is used only by atomic helpers. Atomic drivers don't
> -	 * need to implement it if there's no need to disable anything at the
> -	 * CRTC level.
> -	 *
> -	 * This function is optional.
> -	 */
> -	void (*atomic_disable)(struct drm_crtc *crtc,
> -			       struct drm_atomic_state *state);
> -
> -	/**
> -	 * @get_scanout_position:
> -	 *
> -	 * Called by vblank timestamping code.
> -	 *
> -	 * Returns the current display scanout position from a CRTC and an
> -	 * optional accurate ktime_get() timestamp of when the position was
> -	 * measured. Note that this is a helper callback which is only used
> -	 * if a driver uses drm_crtc_vblank_helper_get_vblank_timestamp()
> -	 * for the @drm_crtc_funcs.get_vblank_timestamp callback.
> -	 *
> -	 * Parameters:
> -	 *
> -	 * crtc:
> -	 *     The CRTC.
> -	 * in_vblank_irq:
> -	 *     True when called from drm_crtc_handle_vblank(). Some drivers
> -	 *     need to apply some workarounds for gpu-specific vblank irq
> -	 *     quirks if the flag is set.
> -	 * vpos:
> -	 *     Target location for current vertical scanout position.
> -	 * hpos:
> -	 *     Target location for current horizontal scanout position.
> -	 * stime:
> -	 *     Target location for timestamp taken immediately before
> -	 *     scanout position query. Can be NULL to skip timestamp.
> -	 * etime:
> -	 *     Target location for timestamp taken immediately after
> -	 *     scanout position query. Can be NULL to skip timestamp.
> -	 * mode:
> -	 *     Current display timings.
> -	 *
> -	 * Returns vpos as a positive number while in active scanout area.
> -	 * Returns vpos as a negative number inside vblank, counting the number
> -	 * of scanlines to go until end of vblank, e.g., -1 means "one scanline
> -	 * until start of active scanout / end of vblank."
> -	 *
> -	 * Returns:
> -	 *
> -	 * True on success, false if a reliable scanout position counter could
> -	 * not be read out.
> -	 */
> -	bool (*get_scanout_position)(struct drm_crtc *crtc,
> -				     bool in_vblank_irq, int *vpos, int *hpos,
> -				     ktime_t *stime, ktime_t *etime,
> -				     const struct drm_display_mode *mode);
> -};
> -
> -/**
> - * drm_crtc_helper_add - sets the helper vtable for a crtc
> - * @crtc: DRM CRTC
> - * @funcs: helper vtable to set for @crtc
> - */
> -static inline void drm_crtc_helper_add(struct drm_crtc *crtc,
> -				       const struct drm_crtc_helper_funcs *funcs)
> -{
> -	crtc->helper_private = funcs;
> -}
> -
> -/**
> - * struct drm_encoder_helper_funcs - helper operations for encoders
> - *
> - * These hooks are used by the legacy CRTC helpers and the new atomic
> - * modesetting helpers.
> - */
> -struct drm_encoder_helper_funcs {
> -	/**
> -	 * @dpms:
> -	 *
> -	 * Callback to control power levels on the encoder.  If the mode passed in
> -	 * is unsupported, the provider must use the next lowest power level.
> -	 * This is used by the legacy encoder helpers to implement DPMS
> -	 * functionality in drm_helper_connector_dpms().
> -	 *
> -	 * This callback is also used to disable an encoder by calling it with
> -	 * DRM_MODE_DPMS_OFF if the @disable hook isn't used.
> -	 *
> -	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> -	 * also support using this hook for enabling and disabling an encoder to
> -	 * facilitate transitions to atomic, but it is deprecated. Instead
> -	 * @enable and @disable should be used.
> -	 */
> -	void (*dpms)(struct drm_encoder *encoder, int mode);
> -
> -	/**
> -	 * @mode_valid:
> -	 *
> -	 * This callback is used to check if a specific mode is valid in this
> -	 * encoder. This should be implemented if the encoder has some sort
> -	 * of restriction in the modes it can display. For example, a given
> -	 * encoder may be responsible to set a clock value. If the clock can
> -	 * not produce all the values for the available modes then this callback
> -	 * can be used to restrict the number of modes to only the ones that
> -	 * can be displayed.
> -	 *
> -	 * This hook is used by the probe helpers to filter the mode list in
> -	 * drm_helper_probe_single_connector_modes(), and it is used by the
> -	 * atomic helpers to validate modes supplied by userspace in
> -	 * drm_atomic_helper_check_modeset().
> -	 *
> -	 * This function is optional.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * Since this function is both called from the check phase of an atomic
> -	 * commit, and the mode validation in the probe paths it is not allowed
> -	 * to look at anything else but the passed-in mode, and validate it
> -	 * against configuration-invariant hardware constraints. Any further
> -	 * limits which depend upon the configuration can only be checked in
> -	 * @mode_fixup or @atomic_check.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * drm_mode_status Enum
> -	 */
> -	enum drm_mode_status (*mode_valid)(struct drm_encoder *crtc,
> -					   const struct drm_display_mode *mode);
> -
> -	/**
> -	 * @mode_fixup:
> -	 *
> -	 * This callback is used to validate and adjust a mode. The parameter
> -	 * mode is the display mode that should be fed to the next element in
> -	 * the display chain, either the final &drm_connector or a &drm_bridge.
> -	 * The parameter adjusted_mode is the input mode the encoder requires. It
> -	 * can be modified by this callback and does not need to match mode. See
> -	 * also &drm_crtc_state.adjusted_mode for more details.
> -	 *
> -	 * This function is used by both legacy CRTC helpers and atomic helpers.
> -	 * This hook is optional.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * This function is called in the check phase of atomic modesets, which
> -	 * can be aborted for any reason (including on userspace's request to
> -	 * just check whether a configuration would be possible). Atomic drivers
> -	 * MUST NOT touch any persistent state (hardware or software) or data
> -	 * structures except the passed in adjusted_mode parameter.
> -	 *
> -	 * This is in contrast to the legacy CRTC helpers where this was
> -	 * allowed.
> -	 *
> -	 * Atomic drivers which need to inspect and adjust more state should
> -	 * instead use the @atomic_check callback. If @atomic_check is used,
> -	 * this hook isn't called since @atomic_check allows a strict superset
> -	 * of the functionality of @mode_fixup.
> -	 *
> -	 * Also beware that userspace can request its own custom modes, neither
> -	 * core nor helpers filter modes to the list of probe modes reported by
> -	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
> -	 * that modes are filtered consistently put any encoder constraints and
> -	 * limits checks into @mode_valid.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * True if an acceptable configuration is possible, false if the modeset
> -	 * operation should be rejected.
> -	 */
> -	bool (*mode_fixup)(struct drm_encoder *encoder,
> -			   const struct drm_display_mode *mode,
> -			   struct drm_display_mode *adjusted_mode);
> -
> -	/**
> -	 * @prepare:
> -	 *
> -	 * This callback should prepare the encoder for a subsequent modeset,
> -	 * which in practice means the driver should disable the encoder if it
> -	 * is running. Most drivers ended up implementing this by calling their
> -	 * @dpms hook with DRM_MODE_DPMS_OFF.
> -	 *
> -	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> -	 * also support using this hook for disabling an encoder to facilitate
> -	 * transitions to atomic, but it is deprecated. Instead @disable should
> -	 * be used.
> -	 */
> -	void (*prepare)(struct drm_encoder *encoder);
> -
> -	/**
> -	 * @commit:
> -	 *
> -	 * This callback should commit the new mode on the encoder after a modeset,
> -	 * which in practice means the driver should enable the encoder.  Most
> -	 * drivers ended up implementing this by calling their @dpms hook with
> -	 * DRM_MODE_DPMS_ON.
> -	 *
> -	 * This callback is used by the legacy CRTC helpers.  Atomic helpers
> -	 * also support using this hook for enabling an encoder to facilitate
> -	 * transitions to atomic, but it is deprecated. Instead @enable should
> -	 * be used.
> -	 */
> -	void (*commit)(struct drm_encoder *encoder);
> -
> -	/**
> -	 * @mode_set:
> -	 *
> -	 * This callback is used to update the display mode of an encoder.
> -	 *
> -	 * Note that the display pipe is completely off when this function is
> -	 * called. Drivers which need hardware to be running before they program
> -	 * the new display mode (because they implement runtime PM) should not
> -	 * use this hook, because the helper library calls it only once and not
> -	 * every time the display pipeline is suspend using either DPMS or the
> -	 * new "ACTIVE" property. Such drivers should instead move all their
> -	 * encoder setup into the @enable callback.
> -	 *
> -	 * This callback is used both by the legacy CRTC helpers and the atomic
> -	 * modeset helpers. It is optional in the atomic helpers.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * If the driver uses the atomic modeset helpers and needs to inspect
> -	 * the connector state or connector display info during mode setting,
> -	 * @atomic_mode_set can be used instead.
> -	 */
> -	void (*mode_set)(struct drm_encoder *encoder,
> -			 struct drm_display_mode *mode,
> -			 struct drm_display_mode *adjusted_mode);
> -
> -	/**
> -	 * @atomic_mode_set:
> -	 *
> -	 * This callback is used to update the display mode of an encoder.
> -	 *
> -	 * Note that the display pipe is completely off when this function is
> -	 * called. Drivers which need hardware to be running before they program
> -	 * the new display mode (because they implement runtime PM) should not
> -	 * use this hook, because the helper library calls it only once and not
> -	 * every time the display pipeline is suspended using either DPMS or the
> -	 * new "ACTIVE" property. Such drivers should instead move all their
> -	 * encoder setup into the @enable callback.
> -	 *
> -	 * This callback is used by the atomic modeset helpers in place of the
> -	 * @mode_set callback, if set by the driver. It is optional and should
> -	 * be used instead of @mode_set if the driver needs to inspect the
> -	 * connector state or display info, since there is no direct way to
> -	 * go from the encoder to the current connector.
> -	 */
> -	void (*atomic_mode_set)(struct drm_encoder *encoder,
> -				struct drm_crtc_state *crtc_state,
> -				struct drm_connector_state *conn_state);
> -
> -	/**
> -	 * @detect:
> -	 *
> -	 * This callback can be used by drivers who want to do detection on the
> -	 * encoder object instead of in connector functions.
> -	 *
> -	 * It is not used by any helper and therefore has purely driver-specific
> -	 * semantics. New drivers shouldn't use this and instead just implement
> -	 * their own private callbacks.
> -	 *
> -	 * FIXME:
> -	 *
> -	 * This should just be converted into a pile of driver vfuncs.
> -	 * Currently radeon, amdgpu and nouveau are using it.
> -	 */
> -	enum drm_connector_status (*detect)(struct drm_encoder *encoder,
> -					    struct drm_connector *connector);
> -
> -	/**
> -	 * @atomic_disable:
> -	 *
> -	 * This callback should be used to disable the encoder. With the atomic
> -	 * drivers it is called before this encoder's CRTC has been shut off
> -	 * using their own &drm_crtc_helper_funcs.atomic_disable hook. If that
> -	 * sequence is too simple drivers can just add their own driver private
> -	 * encoder hooks and call them from CRTC's callback by looping over all
> -	 * encoders connected to it using for_each_encoder_on_crtc().
> -	 *
> -	 * This callback is a variant of @disable that provides the atomic state
> -	 * to the driver. If @atomic_disable is implemented, @disable is not
> -	 * called by the helpers.
> -	 *
> -	 * This hook is only used by atomic helpers. Atomic drivers don't need
> -	 * to implement it if there's no need to disable anything at the encoder
> -	 * level. To ensure that runtime PM handling (using either DPMS or the
> -	 * new "ACTIVE" property) works @atomic_disable must be the inverse of
> -	 * @atomic_enable.
> -	 */
> -	void (*atomic_disable)(struct drm_encoder *encoder,
> -			       struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_enable:
> -	 *
> -	 * This callback should be used to enable the encoder. It is called
> -	 * after this encoder's CRTC has been enabled using their own
> -	 * &drm_crtc_helper_funcs.atomic_enable hook. If that sequence is
> -	 * too simple drivers can just add their own driver private encoder
> -	 * hooks and call them from CRTC's callback by looping over all encoders
> -	 * connected to it using for_each_encoder_on_crtc().
> -	 *
> -	 * This callback is a variant of @enable that provides the atomic state
> -	 * to the driver. If @atomic_enable is implemented, @enable is not
> -	 * called by the helpers.
> -	 *
> -	 * This hook is only used by atomic helpers, it is the opposite of
> -	 * @atomic_disable. Atomic drivers don't need to implement it if there's
> -	 * no need to enable anything at the encoder level. To ensure that
> -	 * runtime PM handling works @atomic_enable must be the inverse of
> -	 * @atomic_disable.
> -	 */
> -	void (*atomic_enable)(struct drm_encoder *encoder,
> -			      struct drm_atomic_state *state);
> -
> -	/**
> -	 * @disable:
> -	 *
> -	 * This callback should be used to disable the encoder. With the atomic
> -	 * drivers it is called before this encoder's CRTC has been shut off
> -	 * using their own &drm_crtc_helper_funcs.disable hook.  If that
> -	 * sequence is too simple drivers can just add their own driver private
> -	 * encoder hooks and call them from CRTC's callback by looping over all
> -	 * encoders connected to it using for_each_encoder_on_crtc().
> -	 *
> -	 * This hook is used both by legacy CRTC helpers and atomic helpers.
> -	 * Atomic drivers don't need to implement it if there's no need to
> -	 * disable anything at the encoder level. To ensure that runtime PM
> -	 * handling (using either DPMS or the new "ACTIVE" property) works
> -	 * @disable must be the inverse of @enable for atomic drivers.
> -	 *
> -	 * For atomic drivers also consider @atomic_disable and save yourself
> -	 * from having to read the NOTE below!
> -	 *
> -	 * NOTE:
> -	 *
> -	 * With legacy CRTC helpers there's a big semantic difference between
> -	 * @disable and other hooks (like @prepare or @dpms) used to shut down a
> -	 * encoder: @disable is only called when also logically disabling the
> -	 * display pipeline and needs to release any resources acquired in
> -	 * @mode_set (like shared PLLs, or again release pinned framebuffers).
> -	 *
> -	 * Therefore @disable must be the inverse of @mode_set plus @commit for
> -	 * drivers still using legacy CRTC helpers, which is different from the
> -	 * rules under atomic.
> -	 */
> -	void (*disable)(struct drm_encoder *encoder);
> -
> -	/**
> -	 * @enable:
> -	 *
> -	 * This callback should be used to enable the encoder. With the atomic
> -	 * drivers it is called after this encoder's CRTC has been enabled using
> -	 * their own &drm_crtc_helper_funcs.enable hook.  If that sequence is
> -	 * too simple drivers can just add their own driver private encoder
> -	 * hooks and call them from CRTC's callback by looping over all encoders
> -	 * connected to it using for_each_encoder_on_crtc().
> -	 *
> -	 * This hook is only used by atomic helpers, it is the opposite of
> -	 * @disable. Atomic drivers don't need to implement it if there's no
> -	 * need to enable anything at the encoder level. To ensure that
> -	 * runtime PM handling (using either DPMS or the new "ACTIVE" property)
> -	 * works @enable must be the inverse of @disable for atomic drivers.
> -	 */
> -	void (*enable)(struct drm_encoder *encoder);
> -
> -	/**
> -	 * @atomic_check:
> -	 *
> -	 * This callback is used to validate encoder state for atomic drivers.
> -	 * Since the encoder is the object connecting the CRTC and connector it
> -	 * gets passed both states, to be able to validate interactions and
> -	 * update the CRTC to match what the encoder needs for the requested
> -	 * connector.
> -	 *
> -	 * Since this provides a strict superset of the functionality of
> -	 * @mode_fixup (the requested and adjusted modes are both available
> -	 * through the passed in &struct drm_crtc_state) @mode_fixup is not
> -	 * called when @atomic_check is implemented.
> -	 *
> -	 * This function is used by the atomic helpers, but it is optional.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * This function is called in the check phase of an atomic update. The
> -	 * driver is not allowed to change anything outside of the free-standing
> -	 * state objects passed-in or assembled in the overall &drm_atomic_state
> -	 * update tracking structure.
> -	 *
> -	 * Also beware that userspace can request its own custom modes, neither
> -	 * core nor helpers filter modes to the list of probe modes reported by
> -	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
> -	 * that modes are filtered consistently put any encoder constraints and
> -	 * limits checks into @mode_valid.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * 0 on success, -EINVAL if the state or the transition can't be
> -	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
> -	 * attempt to obtain another state object ran into a &drm_modeset_lock
> -	 * deadlock.
> -	 */
> -	int (*atomic_check)(struct drm_encoder *encoder,
> -			    struct drm_crtc_state *crtc_state,
> -			    struct drm_connector_state *conn_state);
> -};
> -
> -/**
> - * drm_encoder_helper_add - sets the helper vtable for an encoder
> - * @encoder: DRM encoder
> - * @funcs: helper vtable to set for @encoder
> - */
> -static inline void drm_encoder_helper_add(struct drm_encoder *encoder,
> -					  const struct drm_encoder_helper_funcs *funcs)
> -{
> -	encoder->helper_private = funcs;
> -}
> -
> -/**
> - * struct drm_connector_helper_funcs - helper operations for connectors
> - *
> - * These functions are used by the atomic and legacy modeset helpers and by the
> - * probe helpers.
> - */
> -struct drm_connector_helper_funcs {
> -	/**
> -	 * @get_modes:
> -	 *
> -	 * This function should fill in all modes currently valid for the sink
> -	 * into the &drm_connector.probed_modes list. It should also update the
> -	 * EDID property by calling drm_connector_update_edid_property().
> -	 *
> -	 * The usual way to implement this is to cache the EDID retrieved in the
> -	 * probe callback somewhere in the driver-private connector structure.
> -	 * In this function drivers then parse the modes in the EDID and add
> -	 * them by calling drm_add_edid_modes(). But connectors that drive a
> -	 * fixed panel can also manually add specific modes using
> -	 * drm_mode_probed_add(). Drivers which manually add modes should also
> -	 * make sure that the &drm_connector.display_info,
> -	 * &drm_connector.width_mm and &drm_connector.height_mm fields are
> -	 * filled in.
> -	 *
> -	 * Note that the caller function will automatically add standard VESA
> -	 * DMT modes up to 1024x768 if the .get_modes() helper operation returns
> -	 * no mode and if the connector status is connector_status_connected or
> -	 * connector_status_unknown. There is no need to call
> -	 * drm_add_modes_noedid() manually in that case.
> -	 *
> -	 * Virtual drivers that just want some standard VESA mode with a given
> -	 * resolution can call drm_add_modes_noedid(), and mark the preferred
> -	 * one using drm_set_preferred_mode().
> -	 *
> -	 * This function is only called after the @detect hook has indicated
> -	 * that a sink is connected and when the EDID isn't overridden through
> -	 * sysfs or the kernel commandline.
> -	 *
> -	 * This callback is used by the probe helpers in e.g.
> -	 * drm_helper_probe_single_connector_modes().
> -	 *
> -	 * To avoid races with concurrent connector state updates, the helper
> -	 * libraries always call this with the &drm_mode_config.connection_mutex
> -	 * held. Because of this it's safe to inspect &drm_connector->state.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * The number of modes added by calling drm_mode_probed_add().
> -	 */
> -	int (*get_modes)(struct drm_connector *connector);
> -
> -	/**
> -	 * @detect_ctx:
> -	 *
> -	 * Check to see if anything is attached to the connector. The parameter
> -	 * force is set to false whilst polling, true when checking the
> -	 * connector due to a user request. force can be used by the driver to
> -	 * avoid expensive, destructive operations during automated probing.
> -	 *
> -	 * This callback is optional, if not implemented the connector will be
> -	 * considered as always being attached.
> -	 *
> -	 * This is the atomic version of &drm_connector_funcs.detect.
> -	 *
> -	 * To avoid races against concurrent connector state updates, the
> -	 * helper libraries always call this with ctx set to a valid context,
> -	 * and &drm_mode_config.connection_mutex will always be locked with
> -	 * the ctx parameter set to this ctx. This allows taking additional
> -	 * locks as required.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * &drm_connector_status indicating the connector's status,
> -	 * or the error code returned by drm_modeset_lock(), -EDEADLK.
> -	 */
> -	int (*detect_ctx)(struct drm_connector *connector,
> -			  struct drm_modeset_acquire_ctx *ctx,
> -			  bool force);
> -
> -	/**
> -	 * @mode_valid:
> -	 *
> -	 * Callback to validate a mode for a connector, irrespective of the
> -	 * specific display configuration.
> -	 *
> -	 * This callback is used by the probe helpers to filter the mode list
> -	 * (which is usually derived from the EDID data block from the sink).
> -	 * See e.g. drm_helper_probe_single_connector_modes().
> -	 *
> -	 * This function is optional.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * This only filters the mode list supplied to userspace in the
> -	 * GETCONNECTOR IOCTL. Compared to &drm_encoder_helper_funcs.mode_valid,
> -	 * &drm_crtc_helper_funcs.mode_valid and &drm_bridge_funcs.mode_valid,
> -	 * which are also called by the atomic helpers from
> -	 * drm_atomic_helper_check_modeset(). This allows userspace to force and
> -	 * ignore sink constraint (like the pixel clock limits in the screen's
> -	 * EDID), which is useful for e.g. testing, or working around a broken
> -	 * EDID. Any source hardware constraint (which always need to be
> -	 * enforced) therefore should be checked in one of the above callbacks,
> -	 * and not this one here.
> -	 *
> -	 * To avoid races with concurrent connector state updates, the helper
> -	 * libraries always call this with the &drm_mode_config.connection_mutex
> -	 * held. Because of this it's safe to inspect &drm_connector->state.
> -         *
> -	 * RETURNS:
> -	 *
> -	 * Either &drm_mode_status.MODE_OK or one of the failure reasons in &enum
> -	 * drm_mode_status.
> -	 */
> -	enum drm_mode_status (*mode_valid)(struct drm_connector *connector,
> -					   struct drm_display_mode *mode);
> -
> -	/**
> -	 * @mode_valid_ctx:
> -	 *
> -	 * Callback to validate a mode for a connector, irrespective of the
> -	 * specific display configuration.
> -	 *
> -	 * This callback is used by the probe helpers to filter the mode list
> -	 * (which is usually derived from the EDID data block from the sink).
> -	 * See e.g. drm_helper_probe_single_connector_modes().
> -	 *
> -	 * This function is optional, and is the atomic version of
> -	 * &drm_connector_helper_funcs.mode_valid.
> -	 *
> -	 * To allow for accessing the atomic state of modesetting objects, the
> -	 * helper libraries always call this with ctx set to a valid context,
> -	 * and &drm_mode_config.connection_mutex will always be locked with
> -	 * the ctx parameter set to @ctx. This allows for taking additional
> -	 * locks as required.
> -	 *
> -	 * Even though additional locks may be acquired, this callback is
> -	 * still expected not to take any constraints into account which would
> -	 * be influenced by the currently set display state - such constraints
> -	 * should be handled in the driver's atomic check. For example, if a
> -	 * connector shares display bandwidth with other connectors then it
> -	 * would be ok to validate the minimum bandwidth requirement of a mode
> -	 * against the maximum possible bandwidth of the connector. But it
> -	 * wouldn't be ok to take the current bandwidth usage of other
> -	 * connectors into account, as this would change depending on the
> -	 * display state.
> -	 *
> -	 * Returns:
> -	 * 0 if &drm_connector_helper_funcs.mode_valid_ctx succeeded and wrote
> -	 * the &enum drm_mode_status value to @status, or a negative error
> -	 * code otherwise.
> -	 *
> -	 */
> -	int (*mode_valid_ctx)(struct drm_connector *connector,
> -			      struct drm_display_mode *mode,
> -			      struct drm_modeset_acquire_ctx *ctx,
> -			      enum drm_mode_status *status);
> -
> -	/**
> -	 * @best_encoder:
> -	 *
> -	 * This function should select the best encoder for the given connector.
> -	 *
> -	 * This function is used by both the atomic helpers (in the
> -	 * drm_atomic_helper_check_modeset() function) and in the legacy CRTC
> -	 * helpers.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * In atomic drivers this function is called in the check phase of an
> -	 * atomic update. The driver is not allowed to change or inspect
> -	 * anything outside of arguments passed-in. Atomic drivers which need to
> -	 * inspect dynamic configuration state should instead use
> -	 * @atomic_best_encoder.
> -	 *
> -	 * You can leave this function to NULL if the connector is only
> -	 * attached to a single encoder. In this case, the core will call
> -	 * drm_connector_get_single_encoder() for you.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * Encoder that should be used for the given connector and connector
> -	 * state, or NULL if no suitable encoder exists. Note that the helpers
> -	 * will ensure that encoders aren't used twice, drivers should not check
> -	 * for this.
> -	 */
> -	struct drm_encoder *(*best_encoder)(struct drm_connector *connector);
> -
> -	/**
> -	 * @atomic_best_encoder:
> -	 *
> -	 * This is the atomic version of @best_encoder for atomic drivers which
> -	 * need to select the best encoder depending upon the desired
> -	 * configuration and can't select it statically.
> -	 *
> -	 * This function is used by drm_atomic_helper_check_modeset().
> -	 * If it is not implemented, the core will fallback to @best_encoder
> -	 * (or drm_connector_get_single_encoder() if @best_encoder is NULL).
> -	 *
> -	 * NOTE:
> -	 *
> -	 * This function is called in the check phase of an atomic update. The
> -	 * driver is not allowed to change anything outside of the
> -	 * &drm_atomic_state update tracking structure passed in.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * Encoder that should be used for the given connector and connector
> -	 * state, or NULL if no suitable encoder exists. Note that the helpers
> -	 * will ensure that encoders aren't used twice, drivers should not check
> -	 * for this.
> -	 */
> -	struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector,
> -						   struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_check:
> -	 *
> -	 * This hook is used to validate connector state. This function is
> -	 * called from &drm_atomic_helper_check_modeset, and is called when
> -	 * a connector property is set, or a modeset on the crtc is forced.
> -	 *
> -	 * Because &drm_atomic_helper_check_modeset may be called multiple times,
> -	 * this function should handle being called multiple times as well.
> -	 *
> -	 * This function is also allowed to inspect any other object's state and
> -	 * can add more state objects to the atomic commit if needed. Care must
> -	 * be taken though to ensure that state check and compute functions for
> -	 * these added states are all called, and derived state in other objects
> -	 * all updated. Again the recommendation is to just call check helpers
> -	 * until a maximal configuration is reached.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * This function is called in the check phase of an atomic update. The
> -	 * driver is not allowed to change anything outside of the free-standing
> -	 * state objects passed-in or assembled in the overall &drm_atomic_state
> -	 * update tracking structure.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * 0 on success, -EINVAL if the state or the transition can't be
> -	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
> -	 * attempt to obtain another state object ran into a &drm_modeset_lock
> -	 * deadlock.
> -	 */
> -	int (*atomic_check)(struct drm_connector *connector,
> -			    struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_commit:
> -	 *
> -	 * This hook is to be used by drivers implementing writeback connectors
> -	 * that need a point when to commit the writeback job to the hardware.
> -	 * The writeback_job to commit is available in the new connector state,
> -	 * in &drm_connector_state.writeback_job.
> -	 *
> -	 * This hook is optional.
> -	 *
> -	 * This callback is used by the atomic modeset helpers.
> -	 */
> -	void (*atomic_commit)(struct drm_connector *connector,
> -			      struct drm_atomic_state *state);
> -
> -	/**
> -	 * @prepare_writeback_job:
> -	 *
> -	 * As writeback jobs contain a framebuffer, drivers may need to
> -	 * prepare and clean them up the same way they can prepare and
> -	 * clean up framebuffers for planes. This optional connector operation
> -	 * is used to support the preparation of writeback jobs. The job
> -	 * prepare operation is called from drm_atomic_helper_prepare_planes()
> -	 * for struct &drm_writeback_connector connectors only.
> -	 *
> -	 * This operation is optional.
> -	 *
> -	 * This callback is used by the atomic modeset helpers.
> -	 */
> -	int (*prepare_writeback_job)(struct drm_writeback_connector *connector,
> -				     struct drm_writeback_job *job);
> -	/**
> -	 * @cleanup_writeback_job:
> -	 *
> -	 * This optional connector operation is used to support the
> -	 * cleanup of writeback jobs. The job cleanup operation is called
> -	 * from the existing drm_writeback_cleanup_job() function, invoked
> -	 * both when destroying the job as part of an aborted commit, or when
> -	 * the job completes.
> -	 *
> -	 * This operation is optional.
> -	 *
> -	 * This callback is used by the atomic modeset helpers.
> -	 */
> -	void (*cleanup_writeback_job)(struct drm_writeback_connector *connector,
> -				      struct drm_writeback_job *job);
> -
> -	/**
> -	 * @enable_hpd:
> -	 *
> -	 * Enable hot-plug detection for the connector.
> -	 *
> -	 * This operation is optional.
> -	 *
> -	 * This callback is used by the drm_kms_helper_poll_enable() helpers.
> -	 */
> -	void (*enable_hpd)(struct drm_connector *connector);
> -
> -	/**
> -	 * @disable_hpd:
> -	 *
> -	 * Disable hot-plug detection for the connector.
> -	 *
> -	 * This operation is optional.
> -	 *
> -	 * This callback is used by the drm_kms_helper_poll_disable() helpers.
> -	 */
> -	void (*disable_hpd)(struct drm_connector *connector);
> -};
> -
> -/**
> - * drm_connector_helper_add - sets the helper vtable for a connector
> - * @connector: DRM connector
> - * @funcs: helper vtable to set for @connector
> - */
> -static inline void drm_connector_helper_add(struct drm_connector *connector,
> -					    const struct drm_connector_helper_funcs *funcs)
> -{
> -	connector->helper_private = funcs;
> -}
> -
> -/**
> - * struct drm_plane_helper_funcs - helper operations for planes
> - *
> - * These functions are used by the atomic helpers.
> - */
> -struct drm_plane_helper_funcs {
> -	/**
> -	 * @prepare_fb:
> -	 *
> -	 * This hook is to prepare a framebuffer for scanout by e.g. pinning
> -	 * its backing storage or relocating it into a contiguous block of
> -	 * VRAM. Other possible preparatory work includes flushing caches.
> -	 *
> -	 * This function must not block for outstanding rendering, since it is
> -	 * called in the context of the atomic IOCTL even for async commits to
> -	 * be able to return any errors to userspace. Instead the recommended
> -	 * way is to fill out the &drm_plane_state.fence of the passed-in
> -	 * &drm_plane_state. If the driver doesn't support native fences then
> -	 * equivalent functionality should be implemented through private
> -	 * members in the plane structure.
> -	 *
> -	 * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook
> -	 * set drm_gem_plane_helper_prepare_fb() is called automatically to
> -	 * implement this. Other drivers which need additional plane processing
> -	 * can call drm_gem_plane_helper_prepare_fb() from their @prepare_fb
> -	 * hook.
> -	 *
> -	 * The resources acquired in @prepare_fb persist after the end of
> -	 * the atomic commit. Resources that can be release at the commit's end
> -	 * should be acquired in @begin_fb_access and released in @end_fb_access.
> -	 * For example, a GEM buffer's pin operation belongs into @prepare_fb to
> -	 * keep the buffer pinned after the commit. But a vmap operation for
> -	 * shadow-plane helpers belongs into @begin_fb_access, so that atomic
> -	 * helpers remove the mapping at the end of the commit.
> -	 *
> -	 * The helpers will call @cleanup_fb with matching arguments for every
> -	 * successful call to this hook.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is
> -	 * optional. See @begin_fb_access for preparing per-commit resources.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * 0 on success or one of the following negative error codes allowed by
> -	 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers
> -	 * this callback is the only one which can fail an atomic commit,
> -	 * everything else must complete successfully.
> -	 */
> -	int (*prepare_fb)(struct drm_plane *plane,
> -			  struct drm_plane_state *new_state);
> -	/**
> -	 * @cleanup_fb:
> -	 *
> -	 * This hook is called to clean up any resources allocated for the given
> -	 * framebuffer and plane configuration in @prepare_fb.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is
> -	 * optional.
> -	 */
> -	void (*cleanup_fb)(struct drm_plane *plane,
> -			   struct drm_plane_state *old_state);
> -
> -	/**
> -	 * @begin_fb_access:
> -	 *
> -	 * This hook prepares the plane for access during an atomic commit.
> -	 * In contrast to @prepare_fb, resources acquired in @begin_fb_access,
> -	 * are released at the end of the atomic commit in @end_fb_access.
> -	 *
> -	 * For example, with shadow-plane helpers, the GEM buffer's vmap
> -	 * operation belongs into @begin_fb_access, so that the buffer's
> -	 * memory will be unmapped at the end of the commit in @end_fb_access.
> -	 * But a GEM buffer's pin operation belongs into @prepare_fb
> -	 * to keep the buffer pinned after the commit.
> -	 *
> -	 * The callback is used by the atomic modeset helpers, but it is optional.
> -	 * See @end_fb_cleanup for undoing the effects of @begin_fb_access and
> -	 * @prepare_fb for acquiring resources until the next pageflip.
> -	 *
> -	 * Returns:
> -	 * 0 on success, or a negative errno code otherwise.
> -	 */
> -	int (*begin_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
> -
> -	/**
> -	 * @end_fb_access:
> -	 *
> -	 * This hook cleans up resources allocated by @begin_fb_access. It it called
> -	 * at the end of a commit for the new plane state.
> -	 */
> -	void (*end_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
> -
> -	/**
> -	 * @atomic_check:
> -	 *
> -	 * Drivers should check plane specific constraints in this hook.
> -	 *
> -	 * When using drm_atomic_helper_check_planes() plane's @atomic_check
> -	 * hooks are called before the ones for CRTCs, which allows drivers to
> -	 * request shared resources that the CRTC controls here. For more
> -	 * complicated dependencies the driver can call the provided check helpers
> -	 * multiple times until the computed state has a final configuration and
> -	 * everything has been checked.
> -	 *
> -	 * This function is also allowed to inspect any other object's state and
> -	 * can add more state objects to the atomic commit if needed. Care must
> -	 * be taken though to ensure that state check and compute functions for
> -	 * these added states are all called, and derived state in other objects
> -	 * all updated. Again the recommendation is to just call check helpers
> -	 * until a maximal configuration is reached.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is
> -	 * optional.
> -	 *
> -	 * NOTE:
> -	 *
> -	 * This function is called in the check phase of an atomic update. The
> -	 * driver is not allowed to change anything outside of the
> -	 * &drm_atomic_state update tracking structure.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * 0 on success, -EINVAL if the state or the transition can't be
> -	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
> -	 * attempt to obtain another state object ran into a &drm_modeset_lock
> -	 * deadlock.
> -	 */
> -	int (*atomic_check)(struct drm_plane *plane,
> -			    struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_update:
> -	 *
> -	 * Drivers should use this function to update the plane state.  This
> -	 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and
> -	 * drm_crtc_helper_funcs.atomic_flush callbacks.
> -	 *
> -	 * Note that the power state of the display pipe when this function is
> -	 * called depends upon the exact helpers and calling sequence the driver
> -	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> -	 * the tradeoffs and variants of plane commit helpers.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is optional.
> -	 */
> -	void (*atomic_update)(struct drm_plane *plane,
> -			      struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_enable:
> -	 *
> -	 * Drivers should use this function to unconditionally enable a plane.
> -	 * This hook is called in-between the &drm_crtc_helper_funcs.atomic_begin
> -	 * and drm_crtc_helper_funcs.atomic_flush callbacks. It is called after
> -	 * @atomic_update, which will be called for all enabled planes. Drivers
> -	 * that use @atomic_enable should set up a plane in @atomic_update and
> -	 * afterwards enable the plane in @atomic_enable. If a plane needs to be
> -	 * enabled before installing the scanout buffer, drivers can still do
> -	 * so in @atomic_update.
> -	 *
> -	 * Note that the power state of the display pipe when this function is
> -	 * called depends upon the exact helpers and calling sequence the driver
> -	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> -	 * the tradeoffs and variants of plane commit helpers.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is
> -	 * optional. If implemented, @atomic_enable should be the inverse of
> -	 * @atomic_disable. Drivers that don't want to use either can still
> -	 * implement the complete plane update in @atomic_update.
> -	 */
> -	void (*atomic_enable)(struct drm_plane *plane,
> -			      struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_disable:
> -	 *
> -	 * Drivers should use this function to unconditionally disable a plane.
> -	 * This hook is called in-between the
> -	 * &drm_crtc_helper_funcs.atomic_begin and
> -	 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to
> -	 * @atomic_update, which will be called for disabling planes, too, if
> -	 * the @atomic_disable hook isn't implemented.
> -	 *
> -	 * This hook is also useful to disable planes in preparation of a modeset,
> -	 * by calling drm_atomic_helper_disable_planes_on_crtc() from the
> -	 * &drm_crtc_helper_funcs.disable hook.
> -	 *
> -	 * Note that the power state of the display pipe when this function is
> -	 * called depends upon the exact helpers and calling sequence the driver
> -	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> -	 * the tradeoffs and variants of plane commit helpers.
> -	 *
> -	 * This callback is used by the atomic modeset helpers, but it is
> -	 * optional. It's intended to reverse the effects of @atomic_enable.
> -	 */
> -	void (*atomic_disable)(struct drm_plane *plane,
> -			       struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_async_check:
> -	 *
> -	 * Drivers should set this function pointer to check if the plane's
> -	 * atomic state can be updated in a async fashion. Here async means
> -	 * "not vblank synchronized".
> -	 *
> -	 * This hook is called by drm_atomic_async_check() to establish if a
> -	 * given update can be committed asynchronously, that is, if it can
> -	 * jump ahead of the state currently queued for update.
> -	 *
> -	 * RETURNS:
> -	 *
> -	 * Return 0 on success and any error returned indicates that the update
> -	 * can not be applied in asynchronous manner.
> -	 */
> -	int (*atomic_async_check)(struct drm_plane *plane,
> -				  struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_async_update:
> -	 *
> -	 * Drivers should set this function pointer to perform asynchronous
> -	 * updates of planes, that is, jump ahead of the currently queued
> -	 * state and update the plane. Here async means "not vblank
> -	 * synchronized".
> -	 *
> -	 * This hook is called by drm_atomic_helper_async_commit().
> -	 *
> -	 * An async update will happen on legacy cursor updates. An async
> -	 * update won't happen if there is an outstanding commit modifying
> -	 * the same plane.
> -	 *
> -	 * When doing async_update drivers shouldn't replace the
> -	 * &drm_plane_state but update the current one with the new plane
> -	 * configurations in the new plane_state.
> -	 *
> -	 * Drivers should also swap the framebuffers between current plane
> -	 * state (&drm_plane.state) and new_state.
> -	 * This is required since cleanup for async commits is performed on
> -	 * the new state, rather than old state like for traditional commits.
> -	 * Since we want to give up the reference on the current (old) fb
> -	 * instead of our brand new one, swap them in the driver during the
> -	 * async commit.
> -	 *
> -	 * FIXME:
> -	 *  - It only works for single plane updates
> -	 *  - Async Pageflips are not supported yet
> -	 *  - Some hw might still scan out the old buffer until the next
> -	 *    vblank, however we let go of the fb references as soon as
> -	 *    we run this hook. For now drivers must implement their own workers
> -	 *    for deferring if needed, until a common solution is created.
> -	 */
> -	void (*atomic_async_update)(struct drm_plane *plane,
> -				    struct drm_atomic_state *state);
> -};
> -
> -/**
> - * drm_plane_helper_add - sets the helper vtable for a plane
> - * @plane: DRM plane
> - * @funcs: helper vtable to set for @plane
> - */
> -static inline void drm_plane_helper_add(struct drm_plane *plane,
> -					const struct drm_plane_helper_funcs *funcs)
> -{
> -	plane->helper_private = funcs;
> -}
> -
> -/**
> - * struct drm_mode_config_helper_funcs - global modeset helper operations
> - *
> - * These helper functions are used by the atomic helpers.
> - */
> -struct drm_mode_config_helper_funcs {
> -	/**
> -	 * @atomic_commit_tail:
> -	 *
> -	 * This hook is used by the default atomic_commit() hook implemented in
> -	 * drm_atomic_helper_commit() together with the nonblocking commit
> -	 * helpers (see drm_atomic_helper_setup_commit() for a starting point)
> -	 * to implement blocking and nonblocking commits easily. It is not used
> -	 * by the atomic helpers
> -	 *
> -	 * This function is called when the new atomic state has already been
> -	 * swapped into the various state pointers. The passed in state
> -	 * therefore contains copies of the old/previous state. This hook should
> -	 * commit the new state into hardware. Note that the helpers have
> -	 * already waited for preceding atomic commits and fences, but drivers
> -	 * can add more waiting calls at the start of their implementation, e.g.
> -	 * to wait for driver-internal request for implicit syncing, before
> -	 * starting to commit the update to the hardware.
> -	 *
> -	 * After the atomic update is committed to the hardware this hook needs
> -	 * to call drm_atomic_helper_commit_hw_done(). Then wait for the update
> -	 * to be executed by the hardware, for example using
> -	 * drm_atomic_helper_wait_for_vblanks() or
> -	 * drm_atomic_helper_wait_for_flip_done(), and then clean up the old
> -	 * framebuffers using drm_atomic_helper_cleanup_planes().
> -	 *
> -	 * When disabling a CRTC this hook _must_ stall for the commit to
> -	 * complete. Vblank waits don't work on disabled CRTC, hence the core
> -	 * can't take care of this. And it also can't rely on the vblank event,
> -	 * since that can be signalled already when the screen shows black,
> -	 * which can happen much earlier than the last hardware access needed to
> -	 * shut off the display pipeline completely.
> -	 *
> -	 * This hook is optional, the default implementation is
> -	 * drm_atomic_helper_commit_tail().
> -	 */
> -	void (*atomic_commit_tail)(struct drm_atomic_state *state);
> -
> -	/**
> -	 * @atomic_commit_setup:
> -	 *
> -	 * This hook is used by the default atomic_commit() hook implemented in
> -	 * drm_atomic_helper_commit() together with the nonblocking helpers (see
> -	 * drm_atomic_helper_setup_commit()) to extend the DRM commit setup. It
> -	 * is not used by the atomic helpers.
> -	 *
> -	 * This function is called at the end of
> -	 * drm_atomic_helper_setup_commit(), so once the commit has been
> -	 * properly setup across the generic DRM object states. It allows
> -	 * drivers to do some additional commit tracking that isn't related to a
> -	 * CRTC, plane or connector, tracked in a &drm_private_obj structure.
> -	 *
> -	 * Note that the documentation of &drm_private_obj has more details on
> -	 * how one should implement this.
> -	 *
> -	 * This hook is optional.
> -	 */
> -	int (*atomic_commit_setup)(struct drm_atomic_state *state);
> -};
> +#include <drm/drm_crtc_helper_vtable.h>
> +#include <drm/drm_encoder_helper_vtable.h>
> +#include <drm/drm_connector_helper_vtable.h>
> +#include <drm/drm_plane_helper_vtable.h>
> +#include <drm/drm_mode_config_helper_vtable.h>
>   
>   #endif
> diff --git a/include/drm/drm_plane_helper_vtable.h b/include/drm/drm_plane_helper_vtable.h
> new file mode 100644
> index 0000000000000000..e735aa9733869383
> --- /dev/null
> +++ b/include/drm/drm_plane_helper_vtable.h
> @@ -0,0 +1,297 @@
> +/*
> + * Copyright © 2006 Keith Packard
> + * Copyright © 2007-2008 Dave Airlie
> + * Copyright © 2007-2008 Intel Corporation
> + *   Jesse Barnes <jesse.barnes@intel.com>
> + * Copyright © 2011-2013 Intel Corporation
> + * Copyright © 2015 Intel Corporation
> + *   Daniel Vetter <daniel.vetter@ffwll.ch>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + */
> +
> +#ifndef __DRM_PLANE_HELPER_VTABLE_H__
> +#define __DRM_PLANE_HELPER_VTABLE_H__
> +
> +/**
> + * struct drm_plane_helper_funcs - helper operations for planes
> + *
> + * These functions are used by the atomic helpers.
> + */
> +struct drm_plane_helper_funcs {
> +	/**
> +	 * @prepare_fb:
> +	 *
> +	 * This hook is to prepare a framebuffer for scanout by e.g. pinning
> +	 * its backing storage or relocating it into a contiguous block of
> +	 * VRAM. Other possible preparatory work includes flushing caches.
> +	 *
> +	 * This function must not block for outstanding rendering, since it is
> +	 * called in the context of the atomic IOCTL even for async commits to
> +	 * be able to return any errors to userspace. Instead the recommended
> +	 * way is to fill out the &drm_plane_state.fence of the passed-in
> +	 * &drm_plane_state. If the driver doesn't support native fences then
> +	 * equivalent functionality should be implemented through private
> +	 * members in the plane structure.
> +	 *
> +	 * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook
> +	 * set drm_gem_plane_helper_prepare_fb() is called automatically to
> +	 * implement this. Other drivers which need additional plane processing
> +	 * can call drm_gem_plane_helper_prepare_fb() from their @prepare_fb
> +	 * hook.
> +	 *
> +	 * The resources acquired in @prepare_fb persist after the end of
> +	 * the atomic commit. Resources that can be release at the commit's end
> +	 * should be acquired in @begin_fb_access and released in @end_fb_access.
> +	 * For example, a GEM buffer's pin operation belongs into @prepare_fb to
> +	 * keep the buffer pinned after the commit. But a vmap operation for
> +	 * shadow-plane helpers belongs into @begin_fb_access, so that atomic
> +	 * helpers remove the mapping at the end of the commit.
> +	 *
> +	 * The helpers will call @cleanup_fb with matching arguments for every
> +	 * successful call to this hook.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is
> +	 * optional. See @begin_fb_access for preparing per-commit resources.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * 0 on success or one of the following negative error codes allowed by
> +	 * the &drm_mode_config_funcs.atomic_commit vfunc. When using helpers
> +	 * this callback is the only one which can fail an atomic commit,
> +	 * everything else must complete successfully.
> +	 */
> +	int (*prepare_fb)(struct drm_plane *plane,
> +			  struct drm_plane_state *new_state);
> +	/**
> +	 * @cleanup_fb:
> +	 *
> +	 * This hook is called to clean up any resources allocated for the given
> +	 * framebuffer and plane configuration in @prepare_fb.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is
> +	 * optional.
> +	 */
> +	void (*cleanup_fb)(struct drm_plane *plane,
> +			   struct drm_plane_state *old_state);
> +
> +	/**
> +	 * @begin_fb_access:
> +	 *
> +	 * This hook prepares the plane for access during an atomic commit.
> +	 * In contrast to @prepare_fb, resources acquired in @begin_fb_access,
> +	 * are released at the end of the atomic commit in @end_fb_access.
> +	 *
> +	 * For example, with shadow-plane helpers, the GEM buffer's vmap
> +	 * operation belongs into @begin_fb_access, so that the buffer's
> +	 * memory will be unmapped at the end of the commit in @end_fb_access.
> +	 * But a GEM buffer's pin operation belongs into @prepare_fb
> +	 * to keep the buffer pinned after the commit.
> +	 *
> +	 * The callback is used by the atomic modeset helpers, but it is optional.
> +	 * See @end_fb_cleanup for undoing the effects of @begin_fb_access and
> +	 * @prepare_fb for acquiring resources until the next pageflip.
> +	 *
> +	 * Returns:
> +	 * 0 on success, or a negative errno code otherwise.
> +	 */
> +	int (*begin_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
> +
> +	/**
> +	 * @end_fb_access:
> +	 *
> +	 * This hook cleans up resources allocated by @begin_fb_access. It it called
> +	 * at the end of a commit for the new plane state.
> +	 */
> +	void (*end_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state);
> +
> +	/**
> +	 * @atomic_check:
> +	 *
> +	 * Drivers should check plane specific constraints in this hook.
> +	 *
> +	 * When using drm_atomic_helper_check_planes() plane's @atomic_check
> +	 * hooks are called before the ones for CRTCs, which allows drivers to
> +	 * request shared resources that the CRTC controls here. For more
> +	 * complicated dependencies the driver can call the provided check helpers
> +	 * multiple times until the computed state has a final configuration and
> +	 * everything has been checked.
> +	 *
> +	 * This function is also allowed to inspect any other object's state and
> +	 * can add more state objects to the atomic commit if needed. Care must
> +	 * be taken though to ensure that state check and compute functions for
> +	 * these added states are all called, and derived state in other objects
> +	 * all updated. Again the recommendation is to just call check helpers
> +	 * until a maximal configuration is reached.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is
> +	 * optional.
> +	 *
> +	 * NOTE:
> +	 *
> +	 * This function is called in the check phase of an atomic update. The
> +	 * driver is not allowed to change anything outside of the
> +	 * &drm_atomic_state update tracking structure.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * 0 on success, -EINVAL if the state or the transition can't be
> +	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
> +	 * attempt to obtain another state object ran into a &drm_modeset_lock
> +	 * deadlock.
> +	 */
> +	int (*atomic_check)(struct drm_plane *plane,
> +			    struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_update:
> +	 *
> +	 * Drivers should use this function to update the plane state.  This
> +	 * hook is called in-between the &drm_crtc_helper_funcs.atomic_begin and
> +	 * drm_crtc_helper_funcs.atomic_flush callbacks.
> +	 *
> +	 * Note that the power state of the display pipe when this function is
> +	 * called depends upon the exact helpers and calling sequence the driver
> +	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> +	 * the tradeoffs and variants of plane commit helpers.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is optional.
> +	 */
> +	void (*atomic_update)(struct drm_plane *plane,
> +			      struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_enable:
> +	 *
> +	 * Drivers should use this function to unconditionally enable a plane.
> +	 * This hook is called in-between the &drm_crtc_helper_funcs.atomic_begin
> +	 * and drm_crtc_helper_funcs.atomic_flush callbacks. It is called after
> +	 * @atomic_update, which will be called for all enabled planes. Drivers
> +	 * that use @atomic_enable should set up a plane in @atomic_update and
> +	 * afterwards enable the plane in @atomic_enable. If a plane needs to be
> +	 * enabled before installing the scanout buffer, drivers can still do
> +	 * so in @atomic_update.
> +	 *
> +	 * Note that the power state of the display pipe when this function is
> +	 * called depends upon the exact helpers and calling sequence the driver
> +	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> +	 * the tradeoffs and variants of plane commit helpers.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is
> +	 * optional. If implemented, @atomic_enable should be the inverse of
> +	 * @atomic_disable. Drivers that don't want to use either can still
> +	 * implement the complete plane update in @atomic_update.
> +	 */
> +	void (*atomic_enable)(struct drm_plane *plane,
> +			      struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_disable:
> +	 *
> +	 * Drivers should use this function to unconditionally disable a plane.
> +	 * This hook is called in-between the
> +	 * &drm_crtc_helper_funcs.atomic_begin and
> +	 * drm_crtc_helper_funcs.atomic_flush callbacks. It is an alternative to
> +	 * @atomic_update, which will be called for disabling planes, too, if
> +	 * the @atomic_disable hook isn't implemented.
> +	 *
> +	 * This hook is also useful to disable planes in preparation of a modeset,
> +	 * by calling drm_atomic_helper_disable_planes_on_crtc() from the
> +	 * &drm_crtc_helper_funcs.disable hook.
> +	 *
> +	 * Note that the power state of the display pipe when this function is
> +	 * called depends upon the exact helpers and calling sequence the driver
> +	 * has picked. See drm_atomic_helper_commit_planes() for a discussion of
> +	 * the tradeoffs and variants of plane commit helpers.
> +	 *
> +	 * This callback is used by the atomic modeset helpers, but it is
> +	 * optional. It's intended to reverse the effects of @atomic_enable.
> +	 */
> +	void (*atomic_disable)(struct drm_plane *plane,
> +			       struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_async_check:
> +	 *
> +	 * Drivers should set this function pointer to check if the plane's
> +	 * atomic state can be updated in a async fashion. Here async means
> +	 * "not vblank synchronized".
> +	 *
> +	 * This hook is called by drm_atomic_async_check() to establish if a
> +	 * given update can be committed asynchronously, that is, if it can
> +	 * jump ahead of the state currently queued for update.
> +	 *
> +	 * RETURNS:
> +	 *
> +	 * Return 0 on success and any error returned indicates that the update
> +	 * can not be applied in asynchronous manner.
> +	 */
> +	int (*atomic_async_check)(struct drm_plane *plane,
> +				  struct drm_atomic_state *state);
> +
> +	/**
> +	 * @atomic_async_update:
> +	 *
> +	 * Drivers should set this function pointer to perform asynchronous
> +	 * updates of planes, that is, jump ahead of the currently queued
> +	 * state and update the plane. Here async means "not vblank
> +	 * synchronized".
> +	 *
> +	 * This hook is called by drm_atomic_helper_async_commit().
> +	 *
> +	 * An async update will happen on legacy cursor updates. An async
> +	 * update won't happen if there is an outstanding commit modifying
> +	 * the same plane.
> +	 *
> +	 * When doing async_update drivers shouldn't replace the
> +	 * &drm_plane_state but update the current one with the new plane
> +	 * configurations in the new plane_state.
> +	 *
> +	 * Drivers should also swap the framebuffers between current plane
> +	 * state (&drm_plane.state) and new_state.
> +	 * This is required since cleanup for async commits is performed on
> +	 * the new state, rather than old state like for traditional commits.
> +	 * Since we want to give up the reference on the current (old) fb
> +	 * instead of our brand new one, swap them in the driver during the
> +	 * async commit.
> +	 *
> +	 * FIXME:
> +	 *  - It only works for single plane updates
> +	 *  - Async Pageflips are not supported yet
> +	 *  - Some hw might still scan out the old buffer until the next
> +	 *    vblank, however we let go of the fb references as soon as
> +	 *    we run this hook. For now drivers must implement their own workers
> +	 *    for deferring if needed, until a common solution is created.
> +	 */
> +	void (*atomic_async_update)(struct drm_plane *plane,
> +				    struct drm_atomic_state *state);
> +};
> +
> +/**
> + * drm_plane_helper_add - sets the helper vtable for a plane
> + * @plane: DRM plane
> + * @funcs: helper vtable to set for @plane
> + */
> +static inline void drm_plane_helper_add(struct drm_plane *plane,
> +					const struct drm_plane_helper_funcs *funcs)
> +{
> +	plane->helper_private = funcs;
> +}
> +
> +#endif /* __DRM_PLANE_HELPER_VTABLE_H__ */

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

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Re: [PATCH/RFC 3/3] drm: Split drm_modeset_helper_vtables.h

[Geert Uytterhoeven]

Hi Thomas,

On Thu, Sep 28, 2023 at 3:59 PM Thomas Zimmermann <tzimmermann@suse.de> wrote:
> Am 28.09.23 um 14:16 schrieb Geert Uytterhoeven:
> > <drm/drm_modeset_helper_vtables.h> is the second largest header file in
> > the DRM subsystem, and declares helpers vtables for various DRM
> > components.  Several vtables contain methods with the same name, and all
> > but one vtable do not fit on the screen, making it hard to navigate to
> > the actual method one is interested in.
> >
> > Make it easier for the casual reviewer to keep track by splitting
> > <drm/drm_modeset_helper_vtables.h> in multiple header files, one per DRM
> > component.
>
> I never liked this header either, but do we need new header files? Each
> struct could be appended to the end of the regular header: struct
> drm_plane_helper_funcs to drm_plane.h, drm_connector_helper_func to
> drm_connector.h and so on.

That would work for me, too.  But perhaps we want to maintain a clear
separation between core and helpers?

Note that moving the contents to *_helper.h would be another option,
drm_crtc_helper.h and drm_plane_helper.h already exist.

> > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > ---
> > RFC, a future patch could replace inclusion of
> > <drm/drm_modeset_helper_vtables.h> by inclusion of one or more of the
> > new files, and reduce compilation time.
> > ---
> >   include/drm/drm_connector_helper_vtable.h   |  364 +++++
> >   include/drm/drm_crtc_helper_vtable.h        |  483 ++++++
> >   include/drm/drm_encoder_helper_vtable.h     |  381 +++++
> >   include/drm/drm_mode_config_helper_vtable.h |   97 ++
> >   include/drm/drm_modeset_helper_vtables.h    | 1466 +------------------
> >   include/drm/drm_plane_helper_vtable.h       |  297 ++++
> >   6 files changed, 1627 insertions(+), 1461 deletions(-)
> >   create mode 100644 include/drm/drm_connector_helper_vtable.h
> >   create mode 100644 include/drm/drm_crtc_helper_vtable.h
> >   create mode 100644 include/drm/drm_encoder_helper_vtable.h
> >   create mode 100644 include/drm/drm_mode_config_helper_vtable.h
> >   create mode 100644 include/drm/drm_plane_helper_vtable.h

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH/RFC 3/3] drm: Split drm_modeset_helper_vtables.h

[Thomas Zimmermann]

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Hi

Am 28.09.23 um 17:32 schrieb Geert Uytterhoeven:
> Hi Thomas,
> 
> On Thu, Sep 28, 2023 at 3:59 PM Thomas Zimmermann <tzimmermann@suse.de> wrote:
>> Am 28.09.23 um 14:16 schrieb Geert Uytterhoeven:
>>> <drm/drm_modeset_helper_vtables.h> is the second largest header file in
>>> the DRM subsystem, and declares helpers vtables for various DRM
>>> components.  Several vtables contain methods with the same name, and all
>>> but one vtable do not fit on the screen, making it hard to navigate to
>>> the actual method one is interested in.
>>>
>>> Make it easier for the casual reviewer to keep track by splitting
>>> <drm/drm_modeset_helper_vtables.h> in multiple header files, one per DRM
>>> component.
>>
>> I never liked this header either, but do we need new header files? Each
>> struct could be appended to the end of the regular header: struct
>> drm_plane_helper_funcs to drm_plane.h, drm_connector_helper_func to
>> drm_connector.h and so on.
> 
> That would work for me, too.  But perhaps we want to maintain a clear
> separation between core and helpers?
> 
> Note that moving the contents to *_helper.h would be another option,
> drm_crtc_helper.h and drm_plane_helper.h already exist.

I've taken a closer look at the users of the _vtables header. There's 
code in drm_atomic_helper.c or drm_probe_helper.c that invokes the 
callback functions.

The drivers fill the pointers with code that often comes from other 
helper modules. That code is in files like drm_plane_helper.c or 
drm_crtc_helper.c. There header files are drm_plane_helper.h, etc.

In that context, the _vtables header makes sense, as it separates the 
callers from the callees. Putting the structs into headers like 
drm_plane_helper.h would move it to the callee side.

I suggest to leave the header as it is. The fallout to the code base 
from refactoring seems worse than the current state.

Best regards
Thomas

> 
>>> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
>>> ---
>>> RFC, a future patch could replace inclusion of
>>> <drm/drm_modeset_helper_vtables.h> by inclusion of one or more of the
>>> new files, and reduce compilation time.
>>> ---
>>>    include/drm/drm_connector_helper_vtable.h   |  364 +++++
>>>    include/drm/drm_crtc_helper_vtable.h        |  483 ++++++
>>>    include/drm/drm_encoder_helper_vtable.h     |  381 +++++
>>>    include/drm/drm_mode_config_helper_vtable.h |   97 ++
>>>    include/drm/drm_modeset_helper_vtables.h    | 1466 +------------------
>>>    include/drm/drm_plane_helper_vtable.h       |  297 ++++
>>>    6 files changed, 1627 insertions(+), 1461 deletions(-)
>>>    create mode 100644 include/drm/drm_connector_helper_vtable.h
>>>    create mode 100644 include/drm/drm_crtc_helper_vtable.h
>>>    create mode 100644 include/drm/drm_encoder_helper_vtable.h
>>>    create mode 100644 include/drm/drm_mode_config_helper_vtable.h
>>>    create mode 100644 include/drm/drm_plane_helper_vtable.h
> 
> Gr{oetje,eeting}s,
> 
>                          Geert
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

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Re: [PATCH/RFC 3/3] drm: Split drm_modeset_helper_vtables.h

[Geert Uytterhoeven]

Hi Thomas,

On Fri, Sep 29, 2023 at 9:11 AM Thomas Zimmermann <tzimmermann@suse.de> wrote:
> Am 28.09.23 um 17:32 schrieb Geert Uytterhoeven:
> > On Thu, Sep 28, 2023 at 3:59 PM Thomas Zimmermann <tzimmermann@suse.de> wrote:
> >> Am 28.09.23 um 14:16 schrieb Geert Uytterhoeven:
> >>> <drm/drm_modeset_helper_vtables.h> is the second largest header file in
> >>> the DRM subsystem, and declares helpers vtables for various DRM
> >>> components.  Several vtables contain methods with the same name, and all
> >>> but one vtable do not fit on the screen, making it hard to navigate to
> >>> the actual method one is interested in.
> >>>
> >>> Make it easier for the casual reviewer to keep track by splitting
> >>> <drm/drm_modeset_helper_vtables.h> in multiple header files, one per DRM
> >>> component.
> >>
> >> I never liked this header either, but do we need new header files? Each
> >> struct could be appended to the end of the regular header: struct
> >> drm_plane_helper_funcs to drm_plane.h, drm_connector_helper_func to
> >> drm_connector.h and so on.
> >
> > That would work for me, too.  But perhaps we want to maintain a clear
> > separation between core and helpers?
> >
> > Note that moving the contents to *_helper.h would be another option,
> > drm_crtc_helper.h and drm_plane_helper.h already exist.
>
> I've taken a closer look at the users of the _vtables header. There's
> code in drm_atomic_helper.c or drm_probe_helper.c that invokes the
> callback functions.
>
> The drivers fill the pointers with code that often comes from other
> helper modules. That code is in files like drm_plane_helper.c or
> drm_crtc_helper.c. There header files are drm_plane_helper.h, etc.
>
> In that context, the _vtables header makes sense, as it separates the
> callers from the callees. Putting the structs into headers like
> drm_plane_helper.h would move it to the callee side.
>
> I suggest to leave the header as it is. The fallout to the code base
> from refactoring seems worse than the current state.

To clarify: do you mean keeping the single big drm_modeset_helper_vtables.h,
or the split drm_*_helper_vtable.h set?

Thanks!

> >>> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> >>> ---
> >>> RFC, a future patch could replace inclusion of
> >>> <drm/drm_modeset_helper_vtables.h> by inclusion of one or more of the
> >>> new files, and reduce compilation time.
> >>> ---
> >>>    include/drm/drm_connector_helper_vtable.h   |  364 +++++
> >>>    include/drm/drm_crtc_helper_vtable.h        |  483 ++++++
> >>>    include/drm/drm_encoder_helper_vtable.h     |  381 +++++
> >>>    include/drm/drm_mode_config_helper_vtable.h |   97 ++
> >>>    include/drm/drm_modeset_helper_vtables.h    | 1466 +------------------
> >>>    include/drm/drm_plane_helper_vtable.h       |  297 ++++
> >>>    6 files changed, 1627 insertions(+), 1461 deletions(-)
> >>>    create mode 100644 include/drm/drm_connector_helper_vtable.h
> >>>    create mode 100644 include/drm/drm_crtc_helper_vtable.h
> >>>    create mode 100644 include/drm/drm_encoder_helper_vtable.h
> >>>    create mode 100644 include/drm/drm_mode_config_helper_vtable.h
> >>>    create mode 100644 include/drm/drm_plane_helper_vtable.h

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH/RFC 3/3] drm: Split drm_modeset_helper_vtables.h

[Thomas Zimmermann]

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Hi

Am 29.09.23 um 09:33 schrieb Geert Uytterhoeven:
> Hi Thomas,
> 
> On Fri, Sep 29, 2023 at 9:11 AM Thomas Zimmermann <tzimmermann@suse.de> wrote:
>> Am 28.09.23 um 17:32 schrieb Geert Uytterhoeven:
>>> On Thu, Sep 28, 2023 at 3:59 PM Thomas Zimmermann <tzimmermann@suse.de> wrote:
>>>> Am 28.09.23 um 14:16 schrieb Geert Uytterhoeven:
>>>>> <drm/drm_modeset_helper_vtables.h> is the second largest header file in
>>>>> the DRM subsystem, and declares helpers vtables for various DRM
>>>>> components.  Several vtables contain methods with the same name, and all
>>>>> but one vtable do not fit on the screen, making it hard to navigate to
>>>>> the actual method one is interested in.
>>>>>
>>>>> Make it easier for the casual reviewer to keep track by splitting
>>>>> <drm/drm_modeset_helper_vtables.h> in multiple header files, one per DRM
>>>>> component.
>>>>
>>>> I never liked this header either, but do we need new header files? Each
>>>> struct could be appended to the end of the regular header: struct
>>>> drm_plane_helper_funcs to drm_plane.h, drm_connector_helper_func to
>>>> drm_connector.h and so on.
>>>
>>> That would work for me, too.  But perhaps we want to maintain a clear
>>> separation between core and helpers?
>>>
>>> Note that moving the contents to *_helper.h would be another option,
>>> drm_crtc_helper.h and drm_plane_helper.h already exist.
>>
>> I've taken a closer look at the users of the _vtables header. There's
>> code in drm_atomic_helper.c or drm_probe_helper.c that invokes the
>> callback functions.
>>
>> The drivers fill the pointers with code that often comes from other
>> helper modules. That code is in files like drm_plane_helper.c or
>> drm_crtc_helper.c. There header files are drm_plane_helper.h, etc.
>>
>> In that context, the _vtables header makes sense, as it separates the
>> callers from the callees. Putting the structs into headers like
>> drm_plane_helper.h would move it to the callee side.
>>
>> I suggest to leave the header as it is. The fallout to the code base
>> from refactoring seems worse than the current state.
> 
> To clarify: do you mean keeping the single big drm_modeset_helper_vtables.h,
> or the split drm_*_helper_vtable.h set?

I meant to keep the single big drm_modeset_helper_vtables.h. It's not 
nice to look at, but I think we might easily mess up the header 
dependencies with any changes.

Best regards
Thomas

> 
> Thanks!
> 
>>>>> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
>>>>> ---
>>>>> RFC, a future patch could replace inclusion of
>>>>> <drm/drm_modeset_helper_vtables.h> by inclusion of one or more of the
>>>>> new files, and reduce compilation time.
>>>>> ---
>>>>>     include/drm/drm_connector_helper_vtable.h   |  364 +++++
>>>>>     include/drm/drm_crtc_helper_vtable.h        |  483 ++++++
>>>>>     include/drm/drm_encoder_helper_vtable.h     |  381 +++++
>>>>>     include/drm/drm_mode_config_helper_vtable.h |   97 ++
>>>>>     include/drm/drm_modeset_helper_vtables.h    | 1466 +------------------
>>>>>     include/drm/drm_plane_helper_vtable.h       |  297 ++++
>>>>>     6 files changed, 1627 insertions(+), 1461 deletions(-)
>>>>>     create mode 100644 include/drm/drm_connector_helper_vtable.h
>>>>>     create mode 100644 include/drm/drm_crtc_helper_vtable.h
>>>>>     create mode 100644 include/drm/drm_encoder_helper_vtable.h
>>>>>     create mode 100644 include/drm/drm_mode_config_helper_vtable.h
>>>>>     create mode 100644 include/drm/drm_plane_helper_vtable.h
> 
> Gr{oetje,eeting}s,
> 
>                          Geert
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

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