[media] V4L: Add v4l2_event_subdev_unsubscribe() helper function

Add a v4l2 core helper function that can be used as the subdev
.unsubscribe_event handler. This allows to eliminate some
boilerplate from drivers that are only handling the control events.

Signed-off-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h
index eff85f934b24..be05d019de25 100644
--- a/include/media/v4l2-event.h
+++ b/include/media/v4l2-event.h
@@ -64,6 +64,7 @@
  */
 
 struct v4l2_fh;
+struct v4l2_subdev;
 struct v4l2_subscribed_event;
 struct video_device;
 
@@ -129,5 +130,6 @@ int v4l2_event_subscribe(struct v4l2_fh *fh,
 int v4l2_event_unsubscribe(struct v4l2_fh *fh,
                            const struct v4l2_event_subscription *sub);
 void v4l2_event_unsubscribe_all(struct v4l2_fh *fh);
-
+int v4l2_event_subdev_unsubscribe(struct v4l2_subdev *sd, struct v4l2_fh *fh,
+                                  struct v4l2_event_subscription *sub);
 #endif /* V4L2_EVENT_H */