1 files changed, 24 insertions, 6 deletions

diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index d6ce7b4c019f..4bde00083047 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -295,6 +295,11 @@ EXPORT_SYMBOL(__devm_drm_bridge_alloc);
  */
 void drm_bridge_add(struct drm_bridge *bridge)
 {
+	if (!bridge->container)
+		DRM_WARN("DRM bridge corrupted or not allocated by devm_drm_bridge_alloc()\n");
+
+	drm_bridge_get(bridge);
+
 	mutex_init(&bridge->hpd_mutex);
 
 	if (bridge->ops & DRM_BRIDGE_OP_HDMI)
@@ -342,6 +347,8 @@ void drm_bridge_remove(struct drm_bridge *bridge)
 	mutex_unlock(&bridge_lock);
 
 	mutex_destroy(&bridge->hpd_mutex);
+
+	drm_bridge_put(bridge);
 }
 EXPORT_SYMBOL(drm_bridge_remove);
 
@@ -407,11 +414,17 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
 	if (!encoder || !bridge)
 		return -EINVAL;
 
-	if (previous && (!previous->dev || previous->encoder != encoder))
-		return -EINVAL;
+	drm_bridge_get(bridge);
 
-	if (bridge->dev)
-		return -EBUSY;
+	if (previous && (!previous->dev || previous->encoder != encoder)) {
+		ret = -EINVAL;
+		goto err_put_bridge;
+	}
+
+	if (bridge->dev) {
+		ret = -EBUSY;
+		goto err_put_bridge;
+	}
 
 	bridge->dev = encoder->dev;
 	bridge->encoder = encoder;
@@ -460,6 +473,8 @@ err_reset_bridge:
 			      "failed to attach bridge %pOF to encoder %s\n",
 			      bridge->of_node, encoder->name);
 
+err_put_bridge:
+	drm_bridge_put(bridge);
 	return ret;
 }
 EXPORT_SYMBOL(drm_bridge_attach);
@@ -480,6 +495,7 @@ void drm_bridge_detach(struct drm_bridge *bridge)
 
 	list_del(&bridge->chain_node);
 	bridge->dev = NULL;
+	drm_bridge_put(bridge);
 }
 
 /**
@@ -1211,6 +1227,7 @@ EXPORT_SYMBOL(drm_atomic_bridge_chain_check);
 /**
  * drm_bridge_detect - check if anything is attached to the bridge output
  * @bridge: bridge control structure
+ * @connector: attached connector
  *
  * If the bridge supports output detection, as reported by the
  * DRM_BRIDGE_OP_DETECT bridge ops flag, call &drm_bridge_funcs.detect for the
@@ -1221,12 +1238,13 @@ EXPORT_SYMBOL(drm_atomic_bridge_chain_check);
  * The detection status on success, or connector_status_unknown if the bridge
  * doesn't support output detection.
  */
-enum drm_connector_status drm_bridge_detect(struct drm_bridge *bridge)
+enum drm_connector_status
+drm_bridge_detect(struct drm_bridge *bridge, struct drm_connector *connector)
 {
 	if (!(bridge->ops & DRM_BRIDGE_OP_DETECT))
 		return connector_status_unknown;
 
-	return bridge->funcs->detect(bridge);
+	return bridge->funcs->detect(bridge, connector);
 }
 EXPORT_SYMBOL_GPL(drm_bridge_detect);