diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index 5691dfa..041e7da 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -900,9 +900,22 @@
 nv50_mstc_detect(struct drm_connector *connector, bool force)
 {
 	struct nv50_mstc *mstc = nv50_mstc(connector);
+	enum drm_connector_status conn_status;
+	int ret;
+
 	if (!mstc->port)
 		return connector_status_disconnected;
-	return drm_dp_mst_detect_port(connector, mstc->port->mgr, mstc->port);
+
+	ret = pm_runtime_get_sync(connector->dev->dev);
+	if (ret < 0 && ret != -EACCES)
+		return connector_status_disconnected;
+
+	conn_status = drm_dp_mst_detect_port(connector, mstc->port->mgr,
+					     mstc->port);
+
+	pm_runtime_mark_last_busy(connector->dev->dev);
+	pm_runtime_put_autosuspend(connector->dev->dev);
+	return conn_status;
 }
 
 static void