[PATCH 5.16 0422/1017] drm/edid: Split deep color modes between RGB and YUV444

[Greg Kroah-Hartman]

From: Maxime Ripard <maxime@xxxxxxxxxx>

[ Upstream commit 4adc33f36d80489339f1b43dfeee96bb9ea8e459 ]

The current code assumes that the RGB444 and YUV444 formats are the
same, but the HDMI 2.0 specification states that:

   The three DC_XXbit bits above only indicate support for RGB 4:4:4 at
   that pixel size. Support for YCBCR 4:4:4 in Deep Color modes is
   indicated with the DC_Y444 bit. If DC_Y444 is set, then YCBCR 4:4:4
   is supported for all modes indicated by the DC_XXbit flags.

So if we have YUV444 support and any DC_XXbit flag set but the DC_Y444
flag isn't, we'll assume that we support that deep colour mode for
YUV444 which breaks the specification.

In order to fix this, let's split the edid_hdmi_dc_modes field in struct
drm_display_info into two fields, one for RGB444 and one for YUV444.

Suggested-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Fixes: d0c94692e0a3 ("drm/edid: Parse and handle HDMI deep color modes.")
Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>
Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20220120151625.594595-4-maxime@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c |    2 +-
 drivers/gpu/drm/drm_edid.c                     |    7 ++++---
 drivers/gpu/drm/i915/display/intel_hdmi.c      |    4 ++--
 drivers/gpu/drm/radeon/radeon_connectors.c     |    2 +-
 include/drm/drm_connector.h                    |   12 +++++++++---
 5 files changed, 17 insertions(+), 10 deletions(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
@@ -175,7 +175,7 @@ int amdgpu_connector_get_monitor_bpc(str
 
 			/* Check if bpc is within clock limit. Try to degrade gracefully otherwise */
 			if ((bpc == 12) && (mode_clock * 3/2 > max_tmds_clock)) {
-				if ((connector->display_info.edid_hdmi_dc_modes & DRM_EDID_HDMI_DC_30) &&
+				if ((connector->display_info.edid_hdmi_rgb444_dc_modes & DRM_EDID_HDMI_DC_30) &&
 				    (mode_clock * 5/4 <= max_tmds_clock))
 					bpc = 10;
 				else
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -5076,21 +5076,21 @@ static void drm_parse_hdmi_deep_color_in
 
 	if (hdmi[6] & DRM_EDID_HDMI_DC_30) {
 		dc_bpc = 10;
-		info->edid_hdmi_dc_modes |= DRM_EDID_HDMI_DC_30;
+		info->edid_hdmi_rgb444_dc_modes |= DRM_EDID_HDMI_DC_30;
 		DRM_DEBUG("%s: HDMI sink does deep color 30.\n",
 			  connector->name);
 	}
 
 	if (hdmi[6] & DRM_EDID_HDMI_DC_36) {
 		dc_bpc = 12;
-		info->edid_hdmi_dc_modes |= DRM_EDID_HDMI_DC_36;
+		info->edid_hdmi_rgb444_dc_modes |= DRM_EDID_HDMI_DC_36;
 		DRM_DEBUG("%s: HDMI sink does deep color 36.\n",
 			  connector->name);
 	}
 
 	if (hdmi[6] & DRM_EDID_HDMI_DC_48) {
 		dc_bpc = 16;
-		info->edid_hdmi_dc_modes |= DRM_EDID_HDMI_DC_48;
+		info->edid_hdmi_rgb444_dc_modes |= DRM_EDID_HDMI_DC_48;
 		DRM_DEBUG("%s: HDMI sink does deep color 48.\n",
 			  connector->name);
 	}
@@ -5107,6 +5107,7 @@ static void drm_parse_hdmi_deep_color_in
 
 	/* YCRCB444 is optional according to spec. */
 	if (hdmi[6] & DRM_EDID_HDMI_DC_Y444) {
+		info->edid_hdmi_ycbcr444_dc_modes = info->edid_hdmi_rgb444_dc_modes;
 		DRM_DEBUG("%s: HDMI sink does YCRCB444 in deep color.\n",
 			  connector->name);
 	}
--- a/drivers/gpu/drm/i915/display/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/display/intel_hdmi.c
@@ -1892,7 +1892,7 @@ static bool intel_hdmi_bpc_possible(stru
 		if (ycbcr420_output)
 			return hdmi->y420_dc_modes & DRM_EDID_YCBCR420_DC_36;
 		else
-			return info->edid_hdmi_dc_modes & DRM_EDID_HDMI_DC_36;
+			return info->edid_hdmi_rgb444_dc_modes & DRM_EDID_HDMI_DC_36;
 	case 10:
 		if (DISPLAY_VER(i915) < 11)
 			return false;
@@ -1903,7 +1903,7 @@ static bool intel_hdmi_bpc_possible(stru
 		if (ycbcr420_output)
 			return hdmi->y420_dc_modes & DRM_EDID_YCBCR420_DC_30;
 		else
-			return info->edid_hdmi_dc_modes & DRM_EDID_HDMI_DC_30;
+			return info->edid_hdmi_rgb444_dc_modes & DRM_EDID_HDMI_DC_30;
 	case 8:
 		return true;
 	default:
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -204,7 +204,7 @@ int radeon_get_monitor_bpc(struct drm_co
 
 			/* Check if bpc is within clock limit. Try to degrade gracefully otherwise */
 			if ((bpc == 12) && (mode_clock * 3/2 > max_tmds_clock)) {
-				if ((connector->display_info.edid_hdmi_dc_modes & DRM_EDID_HDMI_DC_30) &&
+				if ((connector->display_info.edid_hdmi_rgb444_dc_modes & DRM_EDID_HDMI_DC_30) &&
 					(mode_clock * 5/4 <= max_tmds_clock))
 					bpc = 10;
 				else
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -566,10 +566,16 @@ struct drm_display_info {
 	bool rgb_quant_range_selectable;
 
 	/**
-	 * @edid_hdmi_dc_modes: Mask of supported hdmi deep color modes. Even
-	 * more stuff redundant with @bus_formats.
+	 * @edid_hdmi_dc_rgb444_modes: Mask of supported hdmi deep color modes
+	 * in RGB 4:4:4. Even more stuff redundant with @bus_formats.
 	 */
-	u8 edid_hdmi_dc_modes;
+	u8 edid_hdmi_rgb444_dc_modes;
+
+	/**
+	 * @edid_hdmi_dc_ycbcr444_modes: Mask of supported hdmi deep color
+	 * modes in YCbCr 4:4:4. Even more stuff redundant with @bus_formats.
+	 */
+	u8 edid_hdmi_ycbcr444_dc_modes;
 
 	/**
 	 * @cea_rev: CEA revision of the HDMI sink.