From c53c2549333b340e2662dc64ec81323476b69a97 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sun, 8 Apr 2012 12:59:46 -0300 Subject: [media] v4l2-event: Add v4l2_subscribed_event_ops Just like with ctrl events, drivers may want to get called back on listener add / remove for other event types too. Rather then special casing all of this in subscribe / unsubscribe event it is better to use ops for this. Signed-off-by: Hans de Goede Acked-by: Hans Verkuil Signed-off-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/v4l2-event.c | 54 ++++++++++++++++++++++++++++++++-------- 1 file changed, 43 insertions(+), 11 deletions(-) (limited to 'drivers/media/video/v4l2-event.c') diff --git a/drivers/media/video/v4l2-event.c b/drivers/media/video/v4l2-event.c index c26ad9637143..0ba2dfa86d07 100644 --- a/drivers/media/video/v4l2-event.c +++ b/drivers/media/video/v4l2-event.c @@ -120,6 +120,14 @@ static void __v4l2_event_queue_fh(struct v4l2_fh *fh, const struct v4l2_event *e if (sev == NULL) return; + /* + * If the event has been added to the fh->subscribed list, but its + * add op has not completed yet elems will be 0, treat this as + * not being subscribed. + */ + if (!sev->elems) + return; + /* Increase event sequence number on fh. */ fh->sequence++; @@ -132,14 +140,14 @@ static void __v4l2_event_queue_fh(struct v4l2_fh *fh, const struct v4l2_event *e sev->first = sev_pos(sev, 1); fh->navailable--; if (sev->elems == 1) { - if (sev->replace) { - sev->replace(&kev->event, ev); + if (sev->ops && sev->ops->replace) { + sev->ops->replace(&kev->event, ev); copy_payload = false; } - } else if (sev->merge) { + } else if (sev->ops && sev->ops->merge) { struct v4l2_kevent *second_oldest = sev->events + sev_pos(sev, 0); - sev->merge(&kev->event, &second_oldest->event); + sev->ops->merge(&kev->event, &second_oldest->event); } } @@ -208,8 +216,14 @@ static void ctrls_merge(const struct v4l2_event *old, struct v4l2_event *new) new->u.ctrl.changes |= old->u.ctrl.changes; } +static const struct v4l2_subscribed_event_ops ctrl_ops = { + .replace = ctrls_replace, + .merge = ctrls_merge, +}; + int v4l2_event_subscribe(struct v4l2_fh *fh, - struct v4l2_event_subscription *sub, unsigned elems) + struct v4l2_event_subscription *sub, unsigned elems, + const struct v4l2_subscribed_event_ops *ops) { struct v4l2_subscribed_event *sev, *found_ev; struct v4l2_ctrl *ctrl = NULL; @@ -236,10 +250,9 @@ int v4l2_event_subscribe(struct v4l2_fh *fh, sev->id = sub->id; sev->flags = sub->flags; sev->fh = fh; - sev->elems = elems; + sev->ops = ops; if (ctrl) { - sev->replace = ctrls_replace; - sev->merge = ctrls_merge; + sev->ops = &ctrl_ops; } spin_lock_irqsave(&fh->vdev->fh_lock, flags); @@ -248,12 +261,27 @@ int v4l2_event_subscribe(struct v4l2_fh *fh, list_add(&sev->list, &fh->subscribed); spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); - /* v4l2_ctrl_add_event uses a mutex, so do this outside the spin lock */ - if (found_ev) + if (found_ev) { kfree(sev); - else if (ctrl) + return 0; /* Already listening */ + } + + if (sev->ops && sev->ops->add) { + int ret = sev->ops->add(sev); + if (ret) { + sev->ops = NULL; + v4l2_event_unsubscribe(fh, sub); + return ret; + } + } + + /* v4l2_ctrl_add_event uses a mutex, so do this outside the spin lock */ + if (ctrl) v4l2_ctrl_add_event(ctrl, sev); + /* Mark as ready for use */ + sev->elems = elems; + return 0; } EXPORT_SYMBOL_GPL(v4l2_event_subscribe); @@ -306,6 +334,10 @@ int v4l2_event_unsubscribe(struct v4l2_fh *fh, } spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + + if (sev && sev->ops && sev->ops->del) + sev->ops->del(sev); + if (sev && sev->type == V4L2_EVENT_CTRL) { struct v4l2_ctrl *ctrl = v4l2_ctrl_find(fh->ctrl_handler, sev->id); -- cgit v1.2.1