[PATCH 18/23] drm/amd/display: Clear MST topology if it fails to resume

[jdhillon]

From: Roman Li <roman.li at amd.com>

[Why]
In case of failure to resume MST topology after suspend, an emtpty
mst tree prevents further mst hub detection on the same connector.
That causes the issue with MST hub hotplug after it's been unplug in
suspend.

[How]
Stop topology manager on the connector after detecting DM_MST failure.

Reviewed-by: Wayne Lin <Wayne.Lin at amd.com>
Acked-by: Jasdeep Dhillon <jdhillon at amd.com>
Signed-off-by: Roman Li <roman.li at amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 88474f04fa9a..2fb7de3b4f5e 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2170,6 +2170,8 @@ static int detect_mst_link_for_all_connectors(struct drm_device *dev)
 				DRM_ERROR("DM_MST: Failed to start MST\n");
 				aconnector->dc_link->type =
 					dc_connection_single;
+				ret = dm_helpers_dp_mst_stop_top_mgr(aconnector->dc_link->ctx,
+								     aconnector->dc_link);
 				break;
 			}
 		}
-- 
2.34.1