diff options
Diffstat (limited to 'drivers/gpu/drm/display/drm_dp_mst_topology.c')
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_mst_topology.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c index a040d7dfced1..ac90118b9e7a 100644 --- a/drivers/gpu/drm/display/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c @@ -6083,6 +6083,7 @@ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port) struct drm_dp_aux *immediate_upstream_aux; struct drm_dp_mst_port *fec_port; struct drm_dp_desc desc = {}; + u8 upstream_dsc; u8 endpoint_fec; u8 endpoint_dsc; @@ -6109,8 +6110,6 @@ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port) /* DP-to-DP peer device */ if (drm_dp_mst_is_virtual_dpcd(immediate_upstream_port)) { - u8 upstream_dsc; - if (drm_dp_dpcd_read(&port->aux, DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1) return NULL; @@ -6156,6 +6155,13 @@ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port) if (drm_dp_has_quirk(&desc, DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD)) { u8 dpcd_ext[DP_RECEIVER_CAP_SIZE]; + if (drm_dp_dpcd_read(immediate_upstream_aux, + DP_DSC_SUPPORT, &upstream_dsc, 1) != 1) + return NULL; + + if (!(upstream_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED)) + return NULL; + if (drm_dp_read_dpcd_caps(immediate_upstream_aux, dpcd_ext) < 0) return NULL; |