diff options
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_dp_mst_topology.c | 27 | ||||
| -rw-r--r-- | include/drm/drm_dp_helper.h | 7 |
3 files changed, 36 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 2faef8bd911f..374cedc6c2ac 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -1165,6 +1165,8 @@ static const struct dpcd_quirk dpcd_quirk_list[] = { { OUI(0x00, 0x10, 0xfa), DEVICE_ID_ANY, false, BIT(DP_DPCD_QUIRK_NO_PSR) }, /* CH7511 seems to leave SINK_COUNT zeroed */ { OUI(0x00, 0x00, 0x00), DEVICE_ID('C', 'H', '7', '5', '1', '1'), false, BIT(DP_DPCD_QUIRK_NO_SINK_COUNT) }, + /* Synaptics DP1.4 MST hubs can support DSC without virtual DPCD */ + { OUI(0x90, 0xCC, 0x24), DEVICE_ID_ANY, true, BIT(DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD) }, }; #undef OUI diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 2b20caa4b7e3..480c71a00cf2 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -5148,6 +5148,7 @@ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port) { struct drm_dp_mst_port *immediate_upstream_port; struct drm_dp_mst_port *fec_port; + struct drm_dp_desc desc = { 0 }; u8 endpoint_fec; u8 endpoint_dsc; @@ -5201,6 +5202,32 @@ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port) return &port->aux; /* + * Synaptics quirk + * Applies to ports for which: + * - Physical aux has Synaptics OUI + * - DPv1.4 or higher + * - Port is on primary branch device + * - Not a VGA adapter (DP_DWN_STRM_PORT_TYPE_ANALOG) + */ + if (drm_dp_read_desc(port->mgr->aux, &desc, true)) + return NULL; + + if (drm_dp_has_quirk(&desc, DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD) && + port->mgr->dpcd[DP_DPCD_REV] >= DP_DPCD_REV_14 && + port->parent == port->mgr->mst_primary) { + u8 downstreamport; + + if (drm_dp_dpcd_read(&port->aux, DP_DOWNSTREAMPORT_PRESENT, + &downstreamport, 1) < 0) + return NULL; + + if ((downstreamport & DP_DWN_STRM_PORT_PRESENT) && + ((downstreamport & DP_DWN_STRM_PORT_TYPE_MASK) + != DP_DWN_STRM_PORT_TYPE_ANALOG)) + return port->mgr->aux; + } + + /* * The check below verifies if the MST sink * connected to the GPU is capable of DSC - * therefore the endpoint needs to be diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 8f8f3632e697..0aeaf4a8951c 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -1522,6 +1522,13 @@ enum drm_dp_quirk { * The driver should ignore SINK_COUNT during detection. */ DP_DPCD_QUIRK_NO_SINK_COUNT, + /** + * @DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD: + * + * The device supports MST DSC despite not supporting Virtual DPCD. + * The DSC caps can be read from the physical aux instead. + */ + DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD, }; /** |