From: Paul Hsieh paul.hsieh@amd.com

[WHY] Some eDP panels' ext caps don't set initial values and the value of dpcd_addr (0x317) is random. It means that sometimes the eDP can be OLED, miniLED and etc, and cause incorrect backlight control interface.

[HOW] Add remove_sink_ext_caps to remove sink ext caps (HDR, OLED and etc)

Cc: Mario Limonciello mario.limonciello@amd.com Cc: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Reviewed-by: Anthony Koo anthony.koo@amd.com Acked-by: Alex Hung alex.hung@amd.com Signed-off-by: Paul Hsieh paul.hsieh@amd.com --- drivers/gpu/drm/amd/display/dc/dc_types.h | 1 + drivers/gpu/drm/amd/display/dc/link/link_detection.c | 3 +++ 2 files changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/dc_types.h b/drivers/gpu/drm/amd/display/dc/dc_types.h index cea666ea66c6..fcb825e4f1bb 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_types.h +++ b/drivers/gpu/drm/amd/display/dc/dc_types.h @@ -177,6 +177,7 @@ struct dc_panel_patch { unsigned int disable_fams; unsigned int skip_avmute; unsigned int mst_start_top_delay; + unsigned int remove_sink_ext_caps; };

struct dc_edid_caps { diff --git a/drivers/gpu/drm/amd/display/dc/link/link_detection.c b/drivers/gpu/drm/amd/display/dc/link/link_detection.c index d6f0f857c05a..f2fe523f914f 100644 --- a/drivers/gpu/drm/amd/display/dc/link/link_detection.c +++ b/drivers/gpu/drm/amd/display/dc/link/link_detection.c @@ -1088,6 +1088,9 @@ static bool detect_link_and_local_sink(struct dc_link *link, if (sink->edid_caps.panel_patch.skip_scdc_overwrite) link->ctx->dc->debug.hdmi20_disable = true;

+ if (sink->edid_caps.panel_patch.remove_sink_ext_caps) + link->dpcd_sink_ext_caps.raw = 0; + if (dc_is_hdmi_signal(link->connector_signal)) read_scdc_caps(link->ddc, link->local_sink);