[PATCH 0/6] drm/fsl-dcu: unload fixes

[PATCH 0/6] drm/fsl-dcu: unload fixes

[Stefan Agner]

Hi all,

This patchset fixes several issues around unloading/unbinding
the driver. There is still one WARNING when unloading the driver
while vblank interrupts are enabled. I am not sure what/who
should make sure that vblank interrupts get disabled before
unloading the driver:

root@colibri-vf:~# echo 40058000.dcu > /sys/bus/platform/drivers/fsl-dcu/unbind
[   37.209656] Console: switching to colour dummy device 80x30
[   37.224954] ------------[ cut here ]------------
[   37.245375] WARNING: CPU: 0 PID: 170 at drivers/gpu/drm/drm_irq.c:380 drm_vblank_cleanup+0x5c/0x8c
...

Hints welcome...

Stefan Agner (6):
  drm/fsl-dcu: detach panel on destroy
  drm/fsl-dcu: handle missing panel gracefully
  drm/fsl-dcu: use variable name dev for struct drm_device
  drm/fsl-dcu: deallocate fbdev CMA on unload
  drm/fsl-dcu: disable output polling on driver unload
  drm/fsl-dcu: implement lastclose callback

 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 50 +++++++++++++++++++++----------
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 23 +++++++++-----
 2 files changed, 50 insertions(+), 23 deletions(-)

-- 
2.8.0

[PATCH 1/6] drm/fsl-dcu: detach panel on destroy

[Stefan Agner]

Disable the earlier attached panel on connector destroy.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
index f586f1e..a07886f 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
@@ -79,7 +79,10 @@ int fsl_dcu_drm_encoder_create(struct fsl_dcu_drm_device *fsl_dev,
 
 static void fsl_dcu_drm_connector_destroy(struct drm_connector *connector)
 {
+	struct fsl_dcu_drm_connector *fsl_con = to_fsl_dcu_connector(connector);
+
 	drm_connector_unregister(connector);
+	drm_panel_detach(fsl_con->panel);
 	drm_connector_cleanup(connector);
 }
 
-- 
2.8.0

[PATCH 2/6] drm/fsl-dcu: handle missing panel gracefully

[Stefan Agner]

If the device tree property fsl,panel is missing, drm_panel_attach
is called with a NULL pointer as first argument. Having a panel is
basically mandatory since RGB is the only supported connector.
Check if a panel node has been found, return -ENODEV and cleanup
otherwise.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
index a07886f..819fe12 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
@@ -171,14 +171,18 @@ int fsl_dcu_drm_connector_create(struct fsl_dcu_drm_device *fsl_dev,
 				      DRM_MODE_DPMS_OFF);
 
 	panel_node = of_parse_phandle(fsl_dev->np, "fsl,panel", 0);
-	if (panel_node) {
-		fsl_dev->connector.panel = of_drm_find_panel(panel_node);
-		if (!fsl_dev->connector.panel) {
-			ret = -EPROBE_DEFER;
-			goto err_sysfs;
-		}
-	of_node_put(panel_node);
+	if (!panel_node) {
+		dev_err(fsl_dev->dev, "fsl,panel property not found\n");
+		ret = -ENODEV;
+		goto err_sysfs;
+	}
+
+	fsl_dev->connector.panel = of_drm_find_panel(panel_node);
+	if (!fsl_dev->connector.panel) {
+		ret = -EPROBE_DEFER;
+		goto err_panel;
 	}
+	of_node_put(panel_node);
 
 	ret = drm_panel_attach(fsl_dev->connector.panel, connector);
 	if (ret) {
@@ -188,6 +192,8 @@ int fsl_dcu_drm_connector_create(struct fsl_dcu_drm_device *fsl_dev,
 
 	return 0;
 
+err_panel:
+	of_node_put(panel_node);
 err_sysfs:
 	drm_connector_unregister(connector);
 err_cleanup:
-- 
2.8.0

[PATCH 3/6] drm/fsl-dcu: use variable name dev for struct drm_device

[Stefan Agner]

The driver uses different variable names for struct drm_device
across functions which is confusing. Stick to the more common
variable name dev. While at it, remove unnecessary if statement
in error handling.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 29 +++++++++++++----------------
 1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
index f62bff2..9cbabb2 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
@@ -63,40 +63,37 @@ static int fsl_dcu_drm_irq_init(struct drm_device *dev)
 	return ret;
 }
 
-static int fsl_dcu_load(struct drm_device *drm, unsigned long flags)
+static int fsl_dcu_load(struct drm_device *dev, unsigned long flags)
 {
-	struct device *dev = drm->dev;
-	struct fsl_dcu_drm_device *fsl_dev = drm->dev_private;
+	struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;
 	int ret;
 
 	ret = fsl_dcu_drm_modeset_init(fsl_dev);
 	if (ret < 0) {
-		dev_err(dev, "failed to initialize mode setting\n");
+		dev_err(dev->dev, "failed to initialize mode setting\n");
 		return ret;
 	}
 
-	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
+	ret = drm_vblank_init(dev, dev->mode_config.num_crtc);
 	if (ret < 0) {
-		dev_err(dev, "failed to initialize vblank\n");
+		dev_err(dev->dev, "failed to initialize vblank\n");
 		goto done;
 	}
-	drm->vblank_disable_allowed = true;
+	dev->vblank_disable_allowed = true;
 
-	ret = fsl_dcu_drm_irq_init(drm);
+	ret = fsl_dcu_drm_irq_init(dev);
 	if (ret < 0)
 		goto done;
-	drm->irq_enabled = true;
+	dev->irq_enabled = true;
 
-	fsl_dcu_fbdev_init(drm);
+	fsl_dcu_fbdev_init(dev);
 
 	return 0;
 done:
-	if (ret) {
-		drm_mode_config_cleanup(drm);
-		drm_vblank_cleanup(drm);
-		drm_irq_uninstall(drm);
-		drm->dev_private = NULL;
-	}
+	drm_mode_config_cleanup(dev);
+	drm_vblank_cleanup(dev);
+	drm_irq_uninstall(dev);
+	dev->dev_private = NULL;
 
 	return ret;
 }
-- 
2.8.0

[PATCH 4/6] drm/fsl-dcu: deallocate fbdev CMA on unload

[Stefan Agner]

Free fbdev CMA using drm_fbdev_cma_fini on unload. This fixes
a warning when unloading the driver:
WARNING: CPU: 0 PID: 164 at drivers/gpu/drm/drm_crtc.c:5930 drm_mode_config_cleanup+0x204/0x208

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
index 9cbabb2..182578d 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
@@ -23,6 +23,7 @@
 
 #include <drm/drmP.h>
 #include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_cma_helper.h>
 #include <drm/drm_gem_cma_helper.h>
 
 #include "fsl_dcu_drm_crtc.h"
@@ -90,6 +91,9 @@ static int fsl_dcu_load(struct drm_device *dev, unsigned long flags)
 
 	return 0;
 done:
+	if (fsl_dev->fbdev)
+		drm_fbdev_cma_fini(fsl_dev->fbdev);
+
 	drm_mode_config_cleanup(dev);
 	drm_vblank_cleanup(dev);
 	drm_irq_uninstall(dev);
@@ -100,6 +104,11 @@ done:
 
 static int fsl_dcu_unload(struct drm_device *dev)
 {
+	struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;
+
+	if (fsl_dev->fbdev)
+		drm_fbdev_cma_fini(fsl_dev->fbdev);
+
 	drm_mode_config_cleanup(dev);
 	drm_vblank_cleanup(dev);
 	drm_irq_uninstall(dev);
-- 
2.8.0

[PATCH 5/6] drm/fsl-dcu: disable output polling on driver unload

[Stefan Agner]

Disabling output polling before unloading the driver.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
index 182578d..f9227b7 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
@@ -91,6 +91,8 @@ static int fsl_dcu_load(struct drm_device *dev, unsigned long flags)
 
 	return 0;
 done:
+	drm_kms_helper_poll_fini(dev);
+
 	if (fsl_dev->fbdev)
 		drm_fbdev_cma_fini(fsl_dev->fbdev);
 
@@ -106,6 +108,8 @@ static int fsl_dcu_unload(struct drm_device *dev)
 {
 	struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;
 
+	drm_kms_helper_poll_fini(dev);
+
 	if (fsl_dev->fbdev)
 		drm_fbdev_cma_fini(fsl_dev->fbdev);
 
-- 
2.8.0

[PATCH 6/6] drm/fsl-dcu: implement lastclose callback

[Stefan Agner]

Use CMA helper drm_fbdev_cma_restore_mode to restore fbdev mode
in process which uses drm/kms dies.

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
index f9227b7..ef41bde 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
@@ -168,6 +168,13 @@ static void fsl_dcu_drm_disable_vblank(struct drm_device *dev,
 	regmap_write(fsl_dev->regmap, DCU_INT_MASK, value);
 }
 
+static void fsl_dcu_drm_lastclose(struct drm_device *dev)
+{
+	struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;
+
+	drm_fbdev_cma_restore_mode(fsl_dev->fbdev);
+}
+
 static const struct file_operations fsl_dcu_drm_fops = {
 	.owner		= THIS_MODULE,
 	.open		= drm_open,
@@ -185,6 +192,7 @@ static const struct file_operations fsl_dcu_drm_fops = {
 static struct drm_driver fsl_dcu_drm_driver = {
 	.driver_features	= DRIVER_HAVE_IRQ | DRIVER_GEM | DRIVER_MODESET
 				| DRIVER_PRIME | DRIVER_ATOMIC,
+	.lastclose		= fsl_dcu_drm_lastclose,
 	.load			= fsl_dcu_load,
 	.unload			= fsl_dcu_unload,
 	.irq_handler		= fsl_dcu_drm_irq,
-- 
2.8.0

Re: [PATCH 0/6] drm/fsl-dcu: unload fixes

[Stefan Agner]

Applied patchset to my fsl-dcu tree.

--
Stefan

On 2016-04-16 22:25, Stefan Agner wrote:
> Hi all,
> 
> This patchset fixes several issues around unloading/unbinding
> the driver. There is still one WARNING when unloading the driver
> while vblank interrupts are enabled. I am not sure what/who
> should make sure that vblank interrupts get disabled before
> unloading the driver:
> 
> root@colibri-vf:~# echo 40058000.dcu > /sys/bus/platform/drivers/fsl-dcu/unbind
> [   37.209656] Console: switching to colour dummy device 80x30
> [   37.224954] ------------[ cut here ]------------
> [   37.245375] WARNING: CPU: 0 PID: 170 at
> drivers/gpu/drm/drm_irq.c:380 drm_vblank_cleanup+0x5c/0x8c
> ...
> 
> Hints welcome...
> 
> Stefan Agner (6):
>   drm/fsl-dcu: detach panel on destroy
>   drm/fsl-dcu: handle missing panel gracefully
>   drm/fsl-dcu: use variable name dev for struct drm_device
>   drm/fsl-dcu: deallocate fbdev CMA on unload
>   drm/fsl-dcu: disable output polling on driver unload
>   drm/fsl-dcu: implement lastclose callback
> 
>  drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 50 +++++++++++++++++++++----------
>  drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 23 +++++++++-----
>  2 files changed, 50 insertions(+), 23 deletions(-)