media: Accept non-subdev sinks in v4l2_create_fwnode_links_to_pad()

The v4l2_create_fwnode_links_to_pad() helper requires the sink pad
passed to it to belong to a subdev. This requirement can be lifted
easily. Make the function usable for non-subdev sinks, which allows
using it with video_device sinks.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

drivers/media/v4l2-core/v4l2-mc.c

@@ -313,14 +313,11 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
 				    struct media_pad *sink, u32 flags)
 {
 	struct fwnode_handle *endpoint;
-	struct v4l2_subdev *sink_sd;
 
 	if (!(sink->flags & MEDIA_PAD_FL_SINK) ||
 	    !is_media_entity_v4l2_subdev(sink->entity))
 		return -EINVAL;
 
-	sink_sd = media_entity_to_v4l2_subdev(sink->entity);
-
 	fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
 		struct fwnode_handle *remote_ep;
 		int src_idx, sink_idx, ret;
@@ -340,7 +337,7 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
 		 * ask the sink to verify it owns the remote endpoint,
 		 * and translate to a sink pad.
 		 */
-		sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,
+		sink_idx = media_entity_get_fwnode_pad(sink->entity,
 						       remote_ep,
 						       MEDIA_PAD_FL_SINK);
 		fwnode_handle_put(remote_ep);
@@ -362,17 +359,17 @@ int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
 		if (media_entity_find_link(src, sink))
 			continue;
 
-		dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",
+		dev_dbg(src_sd->dev, "creating link %s:%d -> %s:%d\n",
 			src_sd->entity.name, src_idx,
-			sink_sd->entity.name, sink_idx);
+			sink->entity->name, sink_idx);
 
 		ret = media_create_pad_link(&src_sd->entity, src_idx,
-					    &sink_sd->entity, sink_idx, flags);
+					    sink->entity, sink_idx, flags);
 		if (ret) {
-			dev_err(sink_sd->dev,
+			dev_err(src_sd->dev,
 				"link %s:%d -> %s:%d failed with %d\n",
 				src_sd->entity.name, src_idx,
-				sink_sd->entity.name, sink_idx, ret);
+				sink->entity->name, sink_idx, ret);
 
 			fwnode_handle_put(endpoint);
 			return ret;

include/media/v4l2-mc.h

@@ -87,17 +87,17 @@ int v4l_vb2q_enable_media_source(struct vb2_queue *q);
 
 /**
  * v4l2_create_fwnode_links_to_pad - Create fwnode-based links from a
- *                                   source subdev to a sink subdev pad.
+ *                                   source subdev to a sink pad.
  *
  * @src_sd: pointer to a source subdev
- * @sink:  pointer to a subdev sink pad
+ * @sink:  pointer to a sink pad
  * @flags: the link flags
  *
  * This function searches for fwnode endpoint connections from a source
  * subdevice to a single sink pad, and if suitable connections are found,
  * translates them into media links to that pad. The function can be
- * called by the sink subdevice, in its v4l2-async notifier subdev bound
- * callback, to create links from a bound source subdevice.
+ * called by the sink, in its v4l2-async notifier bound callback, to create
+ * links from a bound source subdevice.
  *
  * The @flags argument specifies the link flags. The caller shall ensure that
  * the flags are valid regardless of the number of links that may be created.