drm/amd/display: Clear dpcd_sink_ext_caps if not set

commit 923bbfe6c888812db1088d684bd30c24036226d2 upstream.

[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>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/amd/display/dc/dc_types.h b/drivers/gpu/drm/amd/display/dc/dc_types.h
index 445ad79..ba900b0 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dc_types.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_types.h
@@ -189,6 +189,7 @@ 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 c9b6676..e682d27 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/link/link_detection.c
+++ b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
@@ -1085,6 +1085,9 @@ 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);