[PATCH v3 0/3] Add bus format negotiation support for Cadence MHDP8546 driver

[PATCH v3 0/3] Add bus format negotiation support for Cadence MHDP8546 driver

[Yuti Amonkar]

This patch series add bus format negotiation support for Cadence MHDP8546 bridge driver.

The patch series has four patches in the below sequence:
1. drm: bridge: cdns-mhdp8546: Modify atomic_get_input_bus_format bridge function.
   Return all the input formats supported.
2. drm: bridge: cdns-mhdp8546: Remove setting of bus format using connector info 
   Remove the bus format configuration using connector info structure.
3. drm: bridge: cdns-mhdp8546: Retrieve the pixel format and bpc based on bus format 
   Get the pixel format and bpc based on negotiated output bus format.

This patch series is dependent on tidss series [1] for the new connector model support.

[1]
https://patchwork.kernel.org/project/dri-devel/cover/20201201121830.29704-1-nikhil.nd@ti.com/

Version History:

v3:
 - Modify the atomic_get_input_bus_fmts to return the MEDIA_BUS_FMT_RGB121212_1X36
   as default format.along as tidss currently supports only this format.

v2:
 - Remove the Add output bus format negotiation patch from the series, 
   as we use ouput format as MEDIA_BUS_FMT_FIXED and that is  the 
   default value if atomic_get_output_bus_fmts function is not implemented.
 - Return NULL if output format is not MEDIA_BUS_FMT_FIXED.
 - Return the supported color formats based on the display info structure.


Yuti Amonkar (3):
  drm: bridge: cdns-mhdp8546: Modify atomic_get_input_bus_format bridge
    function
  drm: bridge: cdns-mhdp8546: Remove setting of bus format using
    connector info
  drm: bridge: cdns-mhdp8546: Retrieve the pixel format and bpc based on
    bus format

 .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 171 ++++++++++++++----
 1 file changed, 138 insertions(+), 33 deletions(-)

-- 
2.17.1

[PATCH v3 1/3] drm: bridge: cdns-mhdp8546: Modify atomic_get_input_bus_format bridge function

[Yuti Amonkar]

Modify atomic_get_input_bus_format function to return input formats
supported instead of using hardcoded value.

Signed-off-by: Yuti Amonkar <yamonkar@cadence.com>
---
 .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 83 +++++++++++++++++--
 1 file changed, 74 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
index d0ed950f4f87..5ef6adb8bc82 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
@@ -2095,27 +2095,92 @@ cdns_mhdp_bridge_atomic_reset(struct drm_bridge *bridge)
 	return &cdns_mhdp_state->base;
 }
 
+#define MAX_INPUT_FORMAT 11
+
 static u32 *cdns_mhdp_get_input_bus_fmts(struct drm_bridge *bridge,
-				      struct drm_bridge_state *bridge_state,
-				      struct drm_crtc_state *crtc_state,
-				      struct drm_connector_state *conn_state,
-				      u32 output_fmt,
-				      unsigned int *num_input_fmts)
-{
+					 struct drm_bridge_state *bridge_state,
+					 struct drm_crtc_state *crtc_state,
+					 struct drm_connector_state *conn_state,
+					 u32 output_fmt,
+					 unsigned int *num_input_fmts)
+{
+	struct drm_connector *conn = conn_state->connector;
+	struct drm_display_info *info = &conn->display_info;
 	u32 *input_fmts;
 	u32 default_bus_format = MEDIA_BUS_FMT_RGB121212_1X36;
+	unsigned int i = 0;
 
 	*num_input_fmts = 0;
 
 	if (output_fmt != MEDIA_BUS_FMT_FIXED)
 		return NULL;
 
-	input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL);
+	input_fmts = kcalloc(MAX_INPUT_FORMAT,
+			     sizeof(*input_fmts), GFP_KERNEL);
 	if (!input_fmts)
 		return NULL;
 
-	*num_input_fmts = 1;
-	input_fmts[0] = default_bus_format;
+	input_fmts[i++] = default_bus_format;
+
+	if (info->color_formats & DRM_COLOR_FORMAT_RGB444) {
+		if (info->bpc == 16) {
+			input_fmts[i++] = MEDIA_BUS_FMT_RGB161616_1X48;
+			input_fmts[i++] = MEDIA_BUS_FMT_RGB101010_1X30;
+			input_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
+		}
+
+		if (info->bpc == 12) {
+			input_fmts[i++] = MEDIA_BUS_FMT_RGB101010_1X30;
+			input_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
+		}
+
+		if (info->bpc == 10) {
+			input_fmts[i++] = MEDIA_BUS_FMT_RGB101010_1X30;
+			input_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
+		}
+
+		input_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
+	}
+
+	if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444) {
+		if (info->bpc == 16) {
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV16_1X48;
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV12_1X36;
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV10_1X30;
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
+		}
+
+		if (info->bpc == 12) {
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV12_1X36;
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV10_1X30;
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
+		}
+
+		if (info->bpc == 10) {
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV10_1X30;
+			input_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
+		}
+
+		input_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
+	}
+
+	if (info->color_formats & DRM_COLOR_FORMAT_YCRCB422) {
+		if (info->bpc == 12) {
+			input_fmts[i++] = MEDIA_BUS_FMT_UYVY12_1X24;
+			input_fmts[i++] = MEDIA_BUS_FMT_UYVY10_1X20;
+			input_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;
+		}
+
+		if (info->bpc == 10) {
+			input_fmts[i++] = MEDIA_BUS_FMT_UYVY10_1X20;
+			input_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;
+		}
+
+		input_fmts[i++] = MEDIA_BUS_FMT_UYVY8_1X16;
+	}
+
+	*num_input_fmts = i;
+
 	return input_fmts;
 }
 
-- 
2.17.1

[PATCH v3 2/3] drm: bridge: cdns-mhdp8546: Remove setting of bus format using connector info

[Yuti Amonkar]

As we are using bus negotiations for selecting bus format
remove the setting of bus format using the connector info
structure.

Signed-off-by: Yuti Amonkar <yamonkar@cadence.com>
---
 drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
index 5ef6adb8bc82..d9f7eb8249e8 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
@@ -1648,7 +1648,6 @@ static const struct drm_connector_funcs cdns_mhdp_conn_funcs = {
 
 static int cdns_mhdp_connector_init(struct cdns_mhdp_device *mhdp)
 {
-	u32 bus_format = MEDIA_BUS_FMT_RGB121212_1X36;
 	struct drm_connector *conn = &mhdp->connector;
 	struct drm_bridge *bridge = &mhdp->bridge;
 	int ret;
@@ -1669,11 +1668,6 @@ static int cdns_mhdp_connector_init(struct cdns_mhdp_device *mhdp)
 
 	drm_connector_helper_add(conn, &cdns_mhdp_conn_helper_funcs);
 
-	ret = drm_display_info_set_bus_formats(&conn->display_info,
-					       &bus_format, 1);
-	if (ret)
-		return ret;
-
 	ret = drm_connector_attach_encoder(conn, bridge->encoder);
 	if (ret) {
 		dev_err(mhdp->dev, "Failed to attach connector to encoder\n");
-- 
2.17.1

[PATCH v3 3/3] drm: bridge: cdns-mhdp8546: Retrieve the pixel format and bpc based on bus format

[Yuti Amonkar]

Get the pixel format and bpc based on the output bus format
negotiated instead of hardcoding the values.

Signed-off-by: Yuti Amonkar <yamonkar@cadence.com>
---
 .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 82 +++++++++++++++----
 1 file changed, 64 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
index d9f7eb8249e8..2ad5cad46599 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
@@ -1530,24 +1530,8 @@ static int cdns_mhdp_get_modes(struct drm_connector *connector)
 
 	drm_connector_update_edid_property(connector, edid);
 	num_modes = drm_add_edid_modes(connector, edid);
-	kfree(edid);
 
-	/*
-	 * HACK: Warn about unsupported display formats until we deal
-	 *       with them correctly.
-	 */
-	if (connector->display_info.color_formats &&
-	    !(connector->display_info.color_formats &
-	      mhdp->display_fmt.color_format))
-		dev_warn(mhdp->dev,
-			 "%s: No supported color_format found (0x%08x)\n",
-			__func__, connector->display_info.color_formats);
-
-	if (connector->display_info.bpc &&
-	    connector->display_info.bpc < mhdp->display_fmt.bpc)
-		dev_warn(mhdp->dev, "%s: Display bpc only %d < %d\n",
-			 __func__, connector->display_info.bpc,
-			 mhdp->display_fmt.bpc);
+	kfree(edid);
 
 	return num_modes;
 }
@@ -1706,6 +1690,66 @@ static int cdns_mhdp_attach(struct drm_bridge *bridge,
 	return 0;
 }
 
+static void cdns_mhdp_get_display_fmt(struct cdns_mhdp_device *mhdp,
+				      struct drm_bridge_state *state)
+{
+	u32 bus_fmt, bpc, pxlfmt;
+
+	bus_fmt = state->output_bus_cfg.format;
+	switch (bus_fmt) {
+	case MEDIA_BUS_FMT_RGB161616_1X48:
+		pxlfmt = DRM_COLOR_FORMAT_RGB444;
+		bpc = 16;
+		break;
+	case MEDIA_BUS_FMT_YUV16_1X48:
+		pxlfmt = DRM_COLOR_FORMAT_YCRCB444;
+		bpc = 16;
+		break;
+	case MEDIA_BUS_FMT_RGB121212_1X36:
+		pxlfmt = DRM_COLOR_FORMAT_RGB444;
+		bpc = 12;
+		break;
+	case MEDIA_BUS_FMT_UYVY12_1X24:
+		pxlfmt = DRM_COLOR_FORMAT_YCRCB422;
+		bpc = 12;
+		break;
+	case MEDIA_BUS_FMT_YUV12_1X36:
+		pxlfmt = DRM_COLOR_FORMAT_YCRCB444;
+		bpc = 12;
+		break;
+	case MEDIA_BUS_FMT_RGB101010_1X30:
+		pxlfmt = DRM_COLOR_FORMAT_RGB444;
+		bpc = 10;
+		break;
+	case MEDIA_BUS_FMT_UYVY10_1X20:
+		pxlfmt = DRM_COLOR_FORMAT_YCRCB422;
+		bpc = 10;
+		break;
+	case MEDIA_BUS_FMT_YUV10_1X30:
+		pxlfmt = DRM_COLOR_FORMAT_YCRCB444;
+		bpc = 10;
+		break;
+	case MEDIA_BUS_FMT_RGB888_1X24:
+		pxlfmt = DRM_COLOR_FORMAT_RGB444;
+		bpc = 8;
+		break;
+	case MEDIA_BUS_FMT_UYVY8_1X16:
+		pxlfmt = DRM_COLOR_FORMAT_YCRCB422;
+		bpc = 8;
+		break;
+	case MEDIA_BUS_FMT_YUV8_1X24:
+		pxlfmt = DRM_COLOR_FORMAT_YCRCB444;
+		bpc = 8;
+		break;
+	default:
+		pxlfmt = DRM_COLOR_FORMAT_RGB444;
+		bpc = 8;
+	}
+
+	mhdp->display_fmt.color_format = pxlfmt;
+	mhdp->display_fmt.bpc = bpc;
+}
+
 static void cdns_mhdp_configure_video(struct cdns_mhdp_device *mhdp,
 				      const struct drm_display_mode *mode)
 {
@@ -2186,6 +2230,8 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
 	struct cdns_mhdp_device *mhdp = bridge_to_mhdp(bridge);
 	const struct drm_display_mode *mode = &crtc_state->adjusted_mode;
 
+	cdns_mhdp_get_display_fmt(mhdp, bridge_state);
+
 	mutex_lock(&mhdp->link_mutex);
 
 	if (!cdns_mhdp_bandwidth_ok(mhdp, mode, mhdp->link.num_lanes,
@@ -2499,7 +2545,7 @@ static int cdns_mhdp_probe(struct platform_device *pdev)
 	mhdp->link.rate = mhdp->host.link_rate;
 	mhdp->link.num_lanes = mhdp->host.lanes_cnt;
 
-	/* The only currently supported format */
+	/* Initialize color format bpc and y_only to default values*/
 	mhdp->display_fmt.y_only = false;
 	mhdp->display_fmt.color_format = DRM_COLOR_FORMAT_RGB444;
 	mhdp->display_fmt.bpc = 8;
-- 
2.17.1