diff options
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/nouveau/dispnv50/disp.c | 45 |
1 files changed, 36 insertions, 9 deletions
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c index aec6ee1ff4e0..1a06c165a8df 100644 --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c @@ -1142,31 +1142,58 @@ nv50_mstm_enable(struct nv50_mstm *mstm, u8 dpcd, int state) int nv50_mstm_detect(struct nv50_mstm *mstm, u8 dpcd[8], int allow) { - int ret, state = 0; + struct drm_dp_aux *aux; + int ret; + bool old_state, new_state; + u8 mstm_ctrl; if (!mstm) return 0; - if (dpcd[0] >= 0x12) { - ret = drm_dp_dpcd_readb(mstm->mgr.aux, DP_MSTM_CAP, &dpcd[1]); + mutex_lock(&mstm->mgr.lock); + + old_state = mstm->mgr.mst_state; + new_state = old_state; + aux = mstm->mgr.aux; + + if (old_state) { + /* Just check that the MST hub is still as we expect it */ + ret = drm_dp_dpcd_readb(aux, DP_MSTM_CTRL, &mstm_ctrl); + if (ret < 0 || !(mstm_ctrl & DP_MST_EN)) { + DRM_DEBUG_KMS("Hub gone, disabling MST topology\n"); + new_state = false; + } + } else if (dpcd[0] >= 0x12) { + ret = drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &dpcd[1]); if (ret < 0) - return ret; + goto probe_error; if (!(dpcd[1] & DP_MST_CAP)) dpcd[0] = 0x11; else - state = allow; + new_state = allow; } - ret = nv50_mstm_enable(mstm, dpcd[0], state); + if (new_state == old_state) { + mutex_unlock(&mstm->mgr.lock); + return new_state; + } + + ret = nv50_mstm_enable(mstm, dpcd[0], new_state); if (ret) - return ret; + goto probe_error; + + mutex_unlock(&mstm->mgr.lock); - ret = drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, state); + ret = drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, new_state); if (ret) return nv50_mstm_enable(mstm, dpcd[0], 0); - return mstm->mgr.mst_state; + return new_state; + +probe_error: + mutex_unlock(&mstm->mgr.lock); + return ret; } static void |