diff options
Diffstat (limited to 'drivers/media/v4l2-core/v4l2-event.c')
-rw-r--r-- | drivers/media/v4l2-core/v4l2-event.c | 63 |
1 files changed, 35 insertions, 28 deletions
diff --git a/drivers/media/v4l2-core/v4l2-event.c b/drivers/media/v4l2-core/v4l2-event.c index 8d3171c6bee8..1fda2873375f 100644 --- a/drivers/media/v4l2-core/v4l2-event.c +++ b/drivers/media/v4l2-core/v4l2-event.c @@ -119,14 +119,6 @@ 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++; @@ -205,6 +197,22 @@ int v4l2_event_pending(struct v4l2_fh *fh) } EXPORT_SYMBOL_GPL(v4l2_event_pending); +static void __v4l2_event_unsubscribe(struct v4l2_subscribed_event *sev) +{ + struct v4l2_fh *fh = sev->fh; + unsigned int i; + + lockdep_assert_held(&fh->subscribe_lock); + assert_spin_locked(&fh->vdev->fh_lock); + + /* Remove any pending events for this subscription */ + for (i = 0; i < sev->in_use; i++) { + list_del(&sev->events[sev_pos(sev, i)].list); + fh->navailable--; + } + list_del(&sev->list); +} + int v4l2_event_subscribe(struct v4l2_fh *fh, const struct v4l2_event_subscription *sub, unsigned elems, const struct v4l2_subscribed_event_ops *ops) @@ -212,6 +220,7 @@ int v4l2_event_subscribe(struct v4l2_fh *fh, struct v4l2_subscribed_event *sev, *found_ev; unsigned long flags; unsigned i; + int ret = 0; if (sub->type == V4L2_EVENT_ALL) return -EINVAL; @@ -229,6 +238,9 @@ int v4l2_event_subscribe(struct v4l2_fh *fh, sev->flags = sub->flags; sev->fh = fh; sev->ops = ops; + sev->elems = elems; + + mutex_lock(&fh->subscribe_lock); spin_lock_irqsave(&fh->vdev->fh_lock, flags); found_ev = v4l2_event_subscribed(fh, sub->type, sub->id); @@ -237,23 +249,21 @@ int v4l2_event_subscribe(struct v4l2_fh *fh, spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); if (found_ev) { + /* Already listening */ kfree(sev); - return 0; /* Already listening */ - } - - if (sev->ops && sev->ops->add) { - int ret = sev->ops->add(sev, elems); + } else if (sev->ops && sev->ops->add) { + ret = sev->ops->add(sev, elems); if (ret) { - sev->ops = NULL; - v4l2_event_unsubscribe(fh, sub); - return ret; + spin_lock_irqsave(&fh->vdev->fh_lock, flags); + __v4l2_event_unsubscribe(sev); + spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); + kfree(sev); } } - /* Mark as ready for use */ - sev->elems = elems; + mutex_unlock(&fh->subscribe_lock); - return 0; + return ret; } EXPORT_SYMBOL_GPL(v4l2_event_subscribe); @@ -285,30 +295,27 @@ int v4l2_event_unsubscribe(struct v4l2_fh *fh, { struct v4l2_subscribed_event *sev; unsigned long flags; - int i; if (sub->type == V4L2_EVENT_ALL) { v4l2_event_unsubscribe_all(fh); return 0; } + mutex_lock(&fh->subscribe_lock); + spin_lock_irqsave(&fh->vdev->fh_lock, flags); sev = v4l2_event_subscribed(fh, sub->type, sub->id); - if (sev != NULL) { - /* Remove any pending events for this subscription */ - for (i = 0; i < sev->in_use; i++) { - list_del(&sev->events[sev_pos(sev, i)].list); - fh->navailable--; - } - list_del(&sev->list); - } + if (sev != NULL) + __v4l2_event_unsubscribe(sev); spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); if (sev && sev->ops && sev->ops->del) sev->ops->del(sev); + mutex_unlock(&fh->subscribe_lock); + kfree(sev); return 0; |