[PATCH 5.8 033/186] drm/amd/display: Fix passive dongle mistaken as active dongle in EDID emulation

[Greg Kroah-Hartman]

From: Samson Tam <Samson.Tam@xxxxxxx>

[ Upstream commit efbde23a3b0164cef27fd394e7d548f46af5b51d ]

[Why]
dongle_type is set during dongle connection but for passive dongles,
dongle_type is not set. If user starts with an active dongle and
then switches to a passive dongle, it will still report as an active
dongle. Trying to emulate the wrong connecter type results in display
not lighting up.

[How]
Set dpcd_caps.dongle_type for passive dongles in detect_dp().

Signed-off-by: Samson Tam <Samson.Tam@xxxxxxx>
Reviewed-by: Joshua Aberback <Joshua.Aberback@xxxxxxx>
Acked-by: Eryk Brol <eryk.brol@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index bdddb46727b1f..885beb0bcc199 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -767,6 +767,7 @@ static bool detect_dp(struct dc_link *link,
 		sink_caps->signal = dp_passive_dongle_detection(link->ddc,
 								sink_caps,
 								audio_support);
+		link->dpcd_caps.dongle_type = sink_caps->dongle_type;
 	}
 
 	return true;
-- 
2.25.1