The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
Thanks, Sasha
------------------ original commit in Linus's tree ------------------
From 21afc872fbc29cd68cfde816d1df4d55848c3f61 Mon Sep 17 00:00:00 2001 From: Ivan Lipski ivlipski@amd.com Date: Fri, 1 Dec 2023 06:25:16 -0700 Subject: [PATCH] drm/amd/display: Add monitor patch for specific eDP
[WHY] Some eDP panels's ext caps don't write initial value cause the value of dpcd_addr(0x317) is random. It means that sometimes the eDP will clarify it is OLED, miniLED...etc cause the backlight control interface is incorrect.
[HOW] Add a new panel patch to remove sink ext caps(HDR,OLED...etc)
Tested-by: Daniel Wheeler daniel.wheeler@amd.com Reviewed-by: Sun peng Li sunpeng.li@amd.com Acked-by: Rodrigo Siqueira rodrigo.siqueira@amd.com Signed-off-by: Ivan Lipski ivlipski@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c index b4696ec621c45..eaf8d9f482446 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c @@ -64,6 +64,12 @@ static void apply_edid_quirks(struct edid *edid, struct dc_edid_caps *edid_caps) DRM_DEBUG_DRIVER("Disabling FAMS on monitor with panel id %X\n", panel_id); edid_caps->panel_patch.disable_fams = true; break; + /* Workaround for some monitors that do not clear DPCD 0x317 if FreeSync is unsupported */ + case drm_edid_encode_panel_id('A', 'U', 'O', 0xA7AB): + case drm_edid_encode_panel_id('A', 'U', 'O', 0xE69B): + DRM_DEBUG_DRIVER("Clearing DPCD 0x317 on monitor with panel id %X\n", panel_id); + edid_caps->panel_patch.remove_sink_ext_caps = true; + break; default: return; }