This is a note to let you know that I've just added the patch titled
drm: bridge: dw_hdmi: fix preference of RGB modes over YUV420
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-bridge-dw_hdmi-fix-preference-of-rgb-modes-over-.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit fa410bddfa2d422c2fad4a3f1b7bf07f348c5446
Author: Guillaume BRUN <the.cheaterman@xxxxxxxxx>
Date: Wed Nov 16 15:35:23 2022 +0100
drm: bridge: dw_hdmi: fix preference of RGB modes over YUV420
[ Upstream commit d3d6b1bf85aefe0ebc0624574b3bb62f0693914c ]
Cheap monitors sometimes advertise YUV modes they don't really have
(HDMI specification mandates YUV support so even monitors without actual
support will often wrongfully advertise it) which results in YUV matches
and user forum complaints of a red tint to light colour display areas in
common desktop environments.
Moving the default RGB fall-back before YUV selection results in RGB
mode matching in most cases, reducing complaints.
Fixes: 6c3c719936da ("drm/bridge: synopsys: dw-hdmi: add bus format negociation")
Signed-off-by: Guillaume BRUN <the.cheaterman@xxxxxxxxx>
Tested-by: Christian Hewitt <christianshewitt@xxxxxxxxx>
Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>
Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20221116143523.2126-1-the.cheaterman@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index d3129a3e6ab7..8bb403bc712a 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -2594,6 +2594,9 @@ static u32 *dw_hdmi_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
* if supported. In any case the default RGB888 format is added
*/
+ /* Default 8bit RGB fallback */
+ output_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
+
if (max_bpc >= 16 && info->bpc == 16) {
if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444)
output_fmts[i++] = MEDIA_BUS_FMT_YUV16_1X48;
@@ -2627,9 +2630,6 @@ static u32 *dw_hdmi_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444)
output_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
- /* Default 8bit RGB fallback */
- output_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
-
*num_output_fmts = i;
return output_fmts;
