drm/amd/display: Have Payload Properly Created After Resume

commit 482e6ad9adde69d9da08864b4ccf4dfd53edb2f0 upstream.

At drm suspend sequence, MST dc_sink is removed. When commit cached
MST stream back in drm resume sequence, the MST stream payload is not
properly created and added into the payload table. After resume, topology
change is reprobed by removing existing streams first. That leads to
no payload is found in the existing payload table as below error
"[drm] ERROR No payload for [MST PORT:] found in mst state"

1. In encoder .atomic_check routine, remove check existance of dc_sink
2. Bypass MST by checking existence of MST root port. dc_link_type cannot
differentiate MST port before topology is rediscovered.

Reviewed-by: Wayne Lin <wayne.lin@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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 f54d670ab3abcfdd47d1a8eaa7d188802c02d602..0695c7c3d489d27d5d445029e705ed9dd2e33d55 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2813,7 +2813,7 @@ static int dm_resume(void *handle)
                 * this is the case when traversing through already created
                 * MST connectors, should be skipped
                 */
-               if (aconnector->dc_link->type == dc_connection_mst_branch)
+               if (aconnector && aconnector->mst_root)
                        continue;
 
                mutex_lock(&aconnector->hpd_lock);
@@ -6717,7 +6717,7 @@ static int dm_encoder_helper_atomic_check(struct drm_encoder *encoder,
        int clock, bpp = 0;
        bool is_y420 = false;
 
-       if (!aconnector->mst_output_port || !aconnector->dc_sink)
+       if (!aconnector->mst_output_port)
                return 0;
 
        mst_port = aconnector->mst_output_port;