Does what it says on the tin.
Cc: Juston Li juston.li@intel.com Cc: Imre Deak imre.deak@intel.com Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Harry Wentland hwentlan@amd.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Reviewed-by: Sean Paul sean@poorly.run Signed-off-by: Lyude Paul lyude@redhat.com --- drivers/gpu/drm/drm_dp_mst_topology.c | 59 +++++++++++++-------------- 1 file changed, 29 insertions(+), 30 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index c8e218b902ae..d486d15aa002 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -3212,45 +3212,44 @@ EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend); */ int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr) { - int ret = 0; + int ret; + u8 guid[16];
mutex_lock(&mgr->lock); + if (!mgr->mst_primary) + goto out_fail;
- if (mgr->mst_primary) { - int sret; - u8 guid[16]; + ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, + DP_RECEIVER_CAP_SIZE); + if (ret != DP_RECEIVER_CAP_SIZE) { + DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); + goto out_fail; + }
- sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); - if (sret != DP_RECEIVER_CAP_SIZE) { - DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); - ret = -1; - goto out_unlock; - } + ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, + DP_MST_EN | + DP_UP_REQ_EN | + DP_UPSTREAM_IS_SRC); + if (ret < 0) { + DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n"); + goto out_fail; + }
- ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, - DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); - if (ret < 0) { - DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n"); - ret = -1; - goto out_unlock; - } + /* Some hubs forget their guids after they resume */ + ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16); + if (ret != 16) { + DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); + goto out_fail; + } + drm_dp_check_mstb_guid(mgr->mst_primary, guid);
- /* Some hubs forget their guids after they resume */ - sret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16); - if (sret != 16) { - DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); - ret = -1; - goto out_unlock; - } - drm_dp_check_mstb_guid(mgr->mst_primary, guid); + mutex_unlock(&mgr->lock);
- ret = 0; - } else - ret = -1; + return 0;
-out_unlock: +out_fail: mutex_unlock(&mgr->lock); - return ret; + return -1; } EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);