From: Wayne Lin Date: Fri, 25 Oct 2024 04:27:26 +0000 (+0800) Subject: drm/amd/display: Don't write DP_MSTM_CTRL after LT X-Git-Tag: v6.6.86~17 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=404d85a71d5a38c07617f8f658bb18d6d62e2343;p=thirdparty%2Fkernel%2Fstable.git drm/amd/display: Don't write DP_MSTM_CTRL after LT commit bc068194f548ef1f230d96c4398046bf59165992 upstream. [Why] Observe after suspend/resme, we can't light up mst monitors under specific mst hub. The reason is that driver still writes DPCD DP_MSTM_CTRL after LT. It's forbidden even we write the same value for that dpcd register. [How] We already resume the mst branch device dpcd settings during resume_mst_branch_status(). Leverage drm_dp_mst_topology_queue_probe() to only probe the topology, not calling drm_dp_mst_topology_mgr_resume() which will set DP_MSTM_CTRL as well. Reviewed-by: Jerry Zuo Signed-off-by: Wayne Lin Signed-off-by: Zaeem Mohamed Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher [cascardo: adjust context in local declarations] Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Greg Kroah-Hartman --- 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 986ee37688c16..2b7f98a2e36f5 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -2825,8 +2825,7 @@ static int dm_resume(void *handle) struct dm_atomic_state *dm_state = to_dm_atomic_state(dm->atomic_obj.state); enum dc_connection_type new_connection_type = dc_connection_none; struct dc_state *dc_state; - int i, r, j, ret; - bool need_hotplug = false; + int i, r, j; if (amdgpu_in_reset(adev)) { dc_state = dm->cached_dc_state; @@ -3003,23 +3002,16 @@ static int dm_resume(void *handle) aconnector->mst_root) continue; - ret = drm_dp_mst_topology_mgr_resume(&aconnector->mst_mgr, true); - - if (ret < 0) { - dm_helpers_dp_mst_stop_top_mgr(aconnector->dc_link->ctx, - aconnector->dc_link); - need_hotplug = true; - } + drm_dp_mst_topology_queue_probe(&aconnector->mst_mgr); } drm_connector_list_iter_end(&iter); - if (need_hotplug) - drm_kms_helper_hotplug_event(ddev); - amdgpu_dm_irq_resume_late(adev); amdgpu_dm_smu_write_watermarks_table(adev); + drm_kms_helper_hotplug_event(ddev); + return 0; }