[media] media-entitiy: add a function to create multiple links
Sometimes, it is desired to create 1:n and n:1 or even
n:n links between different entities with the same
function.
This is actually needed to support DVB devices that
have multiple frontends. While we could do a function
like that internally at the DVB core, such function is
generic enough to be at media-entity, and it could be
useful on some other places.
So, add such function.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
index eb38bc3..e89d85a 100644
--- a/drivers/media/media-entity.c
+++ b/drivers/media/media-entity.c
@@ -625,6 +625,71 @@
}
EXPORT_SYMBOL_GPL(media_create_pad_link);
+int media_create_pad_links(const struct media_device *mdev,
+ const u32 source_function,
+ struct media_entity *source,
+ const u16 source_pad,
+ const u32 sink_function,
+ struct media_entity *sink,
+ const u16 sink_pad,
+ u32 flags,
+ const bool allow_both_undefined)
+{
+ struct media_entity *entity;
+ unsigned function;
+ int ret;
+
+ /* Trivial case: 1:1 relation */
+ if (source && sink)
+ return media_create_pad_link(source, source_pad,
+ sink, sink_pad, flags);
+
+ /* Worse case scenario: n:n relation */
+ if (!source && !sink) {
+ if (!allow_both_undefined)
+ return 0;
+ media_device_for_each_entity(source, mdev) {
+ if (source->function != source_function)
+ continue;
+ media_device_for_each_entity(sink, mdev) {
+ if (sink->function != sink_function)
+ continue;
+ ret = media_create_pad_link(source, source_pad,
+ sink, sink_pad,
+ flags);
+ if (ret)
+ return ret;
+ flags &= ~(MEDIA_LNK_FL_ENABLED |
+ MEDIA_LNK_FL_IMMUTABLE);
+ }
+ }
+ return 0;
+ }
+
+ /* Handle 1:n and n:1 cases */
+ if (source)
+ function = sink_function;
+ else
+ function = source_function;
+
+ media_device_for_each_entity(entity, mdev) {
+ if (entity->function != function)
+ continue;
+
+ if (source)
+ ret = media_create_pad_link(source, source_pad,
+ entity, sink_pad, flags);
+ else
+ ret = media_create_pad_link(entity, source_pad,
+ sink, sink_pad, flags);
+ if (ret)
+ return ret;
+ flags &= ~(MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE);
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(media_create_pad_links);
+
void __media_entity_remove_links(struct media_entity *entity)
{
struct media_link *link, *tmp;
