drm/amd/display: clear remote dc_sink when stop mst

[Why]
Currently, we don't have code path to release remote dc_sink when unplug
MST hub from the system. After few times hotplug, we hit the limition of
maximum number of remote dc_sink and can't light up new connected monitor
anymore.

[How]
Releasing all remote dc_sink at dm_helpers_dp_mst_stop_top_mgr() was
removed by previous patch. Restore it.

Reviewed-by: Jerry Zuo <Jerry.Zuo@amd.com>
Acked-by: Solomon Chiu <solomon.chiu@amd.com>
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index db4ab01..010498f 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -451,6 +451,7 @@ bool dm_helpers_dp_mst_stop_top_mgr(
                struct dc_link *link)
 {
        struct amdgpu_dm_connector *aconnector = link->priv;
+       uint8_t i;
 
        if (!aconnector) {
                DRM_ERROR("Failed to find connector for link!");
@@ -460,9 +461,26 @@ bool dm_helpers_dp_mst_stop_top_mgr(
        DRM_INFO("DM_MST: stopping TM on aconnector: %p [id: %d]\n",
                        aconnector, aconnector->base.base.id);
 
-       if (aconnector->mst_mgr.mst_state == true)
+       if (aconnector->mst_mgr.mst_state == true) {
                drm_dp_mst_topology_mgr_set_mst(&aconnector->mst_mgr, false);
 
+               for (i = 0; i < MAX_SINKS_PER_LINK; i++) {
+                       if (link->remote_sinks[i] == NULL)
+                               continue;
+
+                       if (link->remote_sinks[i]->sink_signal ==
+                           SIGNAL_TYPE_DISPLAY_PORT_MST) {
+                               dc_link_remove_remote_sink(link, link->remote_sinks[i]);
+
+                               if (aconnector->dc_sink) {
+                                       dc_sink_release(aconnector->dc_sink);
+                                       aconnector->dc_sink = NULL;
+                                       aconnector->dc_link->cur_link_settings.lane_count = 0;
+                               }
+                       }
+               }
+       }
+
        return false;
 }