From 07cb2ad65e7c2bc5cb69c0ae21d3cfce96e247ab Mon Sep 17 00:00:00 2001 From: Eric Yang Date: Tue, 12 Jun 2018 18:37:12 -0400 Subject: [PATCH 4894/5725] drm/amd/display: support access ddc for mst branch [Why] Megachip dockings accesses ddc line through display driver when installing FW. Previously, we would fail every transaction because link attached to mst branch did not have their ddc transaction type set. [How] Set ddc transaction type when mst branch is connected. Signed-off-by: Eric Yang Reviewed-by: Charlene Liu Acked-by: Harry Wentland Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/dc/core/dc_link.c | 4 ++++ 1 file changed, 4 insertions(+) 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 e88dc58..9d5ccb6 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -498,6 +498,10 @@ static bool detect_dp( sink_caps->signal = SIGNAL_TYPE_DISPLAY_PORT_MST; link->type = dc_connection_mst_branch; + dal_ddc_service_set_transaction_type( + link->ddc, + sink_caps->transaction_type); + /* * This call will initiate MST topology discovery. Which * will detect MST ports and add new DRM connector DRM -- 2.7.4