[v2,6/7] V4L: Events: Sequence numbers

Commit Message

Sakari Ailus Feb. 7, 2010, 6:40 p.m. UTC

None

Patch

diff --git a/drivers/media/video/v4l2-event.c b/drivers/media/video/v4l2-event.c
index a95cde0..cd744d0 100644
--- a/drivers/media/video/v4l2-event.c
+++ b/drivers/media/video/v4l2-event.c
@@ -89,6 +89,7 @@  int v4l2_event_init(struct v4l2_fh *fh, unsigned int n)
 	INIT_LIST_HEAD(&fh->events->subscribed);
 
 	atomic_set(&fh->events->navailable, 0);
+	atomic_set(&fh->events->sequence, -1);
 
 	ret = v4l2_event_alloc(fh, n);
 	if (ret < 0)
@@ -166,15 +167,23 @@  void v4l2_event_queue(struct video_device *vdev, struct v4l2_event *ev)
 	list_for_each_entry(fh, &vdev->fhs.list, list) {
 		struct v4l2_events *events = fh->events;
 		struct v4l2_kevent *kev;
+		u32 sequence;
 
-		/* Do we have any free events and are we subscribed? */
-		if (list_empty(&events->free) ||
-		    !__v4l2_event_subscribed(fh, ev->type))
+		/* Are we subscribed? */
+		if (!__v4l2_event_subscribed(fh, ev->type))
+			continue;
+
+		/* Increase event sequence number on fh. */
+		sequence = atomic_inc_return(&events->sequence);
+
+		/* Do we have any free events? */
+		if (list_empty(&events->free))
 			continue;
 
 		/* Take one and fill it. */
 		kev = list_first_entry(&events->free, struct v4l2_kevent, list);
 		kev->event = *ev;
+		kev->event.sequence = sequence;
 		list_move_tail(&kev->list, &events->available);
 
 		atomic_inc(&events->navailable);
diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h
index 282d215..3db0c3b 100644
--- a/include/media/v4l2-event.h
+++ b/include/media/v4l2-event.h
@@ -49,6 +49,7 @@  struct v4l2_events {
 	struct list_head	available; /* Dequeueable event */
 	atomic_t                navailable;
 	struct list_head	free; /* Events ready for use */
+	atomic_t                sequence;
 };
 
 int v4l2_event_alloc(struct v4l2_fh *fh, unsigned int n);