media: entity: Skip non-data links in graph iteration

When iterating over the media graph, don't follow links that are not
data links.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Scally <djrscally@gmail.com>
Reviewed-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/mc/mc-entity.c

@@ -295,6 +295,12 @@ static void media_graph_walk_iter(struct media_graph *graph)
 
 	link = list_entry(link_top(graph), typeof(*link), list);
 
+	/* If the link is not a data link, don't follow it */
+	if ((link->flags & MEDIA_LNK_FL_LINK_TYPE) != MEDIA_LNK_FL_DATA_LINK) {
+		link_top(graph) = link_top(graph)->next;
+		return;
+	}
+
 	/* The link is not enabled so we do not follow. */
 	if (!(link->flags & MEDIA_LNK_FL_ENABLED)) {
 		link_top(graph) = link_top(graph)->next;