4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Leo (Hanghong) Ma <hanghong.ma@xxxxxxx> commit d2f0b53bda3193874f3905bc839888f895d1c0cf upstream. [Why] drm_dp_mst_topology_mgr_suspend() is added into the new reboot sequence, which disables the UP request at the beginning. Therefore sideband messages are blocked. [How] Finish MST sideband message transaction before UP request is suppressed. Signed-off-by: Leo (Hanghong) Ma <hanghong.ma@xxxxxxx> Reviewed-by: Roman Li <Roman.Li@xxxxxxx> Acked-by: Leo Li <sunpeng.li@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -704,12 +704,13 @@ static int dm_suspend(void *handle) struct amdgpu_display_manager *dm = &adev->dm; int ret = 0; + WARN_ON(adev->dm.cached_state); + adev->dm.cached_state = drm_atomic_helper_suspend(adev->ddev); + s3_handle_mst(adev->ddev, true); amdgpu_dm_irq_suspend(adev); - WARN_ON(adev->dm.cached_state); - adev->dm.cached_state = drm_atomic_helper_suspend(adev->ddev); dc_set_power_state(dm->dc, DC_ACPI_CM_POWER_STATE_D3);