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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /drivers/media/video/v4l2-event.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'drivers/media/video/v4l2-event.c')
-rw-r--r--drivers/media/video/v4l2-event.c320
1 files changed, 320 insertions, 0 deletions
diff --git a/drivers/media/video/v4l2-event.c b/drivers/media/video/v4l2-event.c
new file mode 100644
index 00000000..c26ad963
--- /dev/null
+++ b/drivers/media/video/v4l2-event.c
@@ -0,0 +1,320 @@
+/*
+ * v4l2-event.c
+ *
+ * V4L2 events.
+ *
+ * Copyright (C) 2009--2010 Nokia Corporation.
+ *
+ * Contact: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <media/v4l2-dev.h>
+#include <media/v4l2-fh.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-ctrls.h>
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+static unsigned sev_pos(const struct v4l2_subscribed_event *sev, unsigned idx)
+{
+ idx += sev->first;
+ return idx >= sev->elems ? idx - sev->elems : idx;
+}
+
+static int __v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event)
+{
+ struct v4l2_kevent *kev;
+ unsigned long flags;
+
+ spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+
+ if (list_empty(&fh->available)) {
+ spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+ return -ENOENT;
+ }
+
+ WARN_ON(fh->navailable == 0);
+
+ kev = list_first_entry(&fh->available, struct v4l2_kevent, list);
+ list_del(&kev->list);
+ fh->navailable--;
+
+ kev->event.pending = fh->navailable;
+ *event = kev->event;
+ kev->sev->first = sev_pos(kev->sev, 1);
+ kev->sev->in_use--;
+
+ spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+
+ return 0;
+}
+
+int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event,
+ int nonblocking)
+{
+ int ret;
+
+ if (nonblocking)
+ return __v4l2_event_dequeue(fh, event);
+
+ /* Release the vdev lock while waiting */
+ if (fh->vdev->lock)
+ mutex_unlock(fh->vdev->lock);
+
+ do {
+ ret = wait_event_interruptible(fh->wait,
+ fh->navailable != 0);
+ if (ret < 0)
+ break;
+
+ ret = __v4l2_event_dequeue(fh, event);
+ } while (ret == -ENOENT);
+
+ if (fh->vdev->lock)
+ mutex_lock(fh->vdev->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(v4l2_event_dequeue);
+
+/* Caller must hold fh->vdev->fh_lock! */
+static struct v4l2_subscribed_event *v4l2_event_subscribed(
+ struct v4l2_fh *fh, u32 type, u32 id)
+{
+ struct v4l2_subscribed_event *sev;
+
+ assert_spin_locked(&fh->vdev->fh_lock);
+
+ list_for_each_entry(sev, &fh->subscribed, list)
+ if (sev->type == type && sev->id == id)
+ return sev;
+
+ return NULL;
+}
+
+static void __v4l2_event_queue_fh(struct v4l2_fh *fh, const struct v4l2_event *ev,
+ const struct timespec *ts)
+{
+ struct v4l2_subscribed_event *sev;
+ struct v4l2_kevent *kev;
+ bool copy_payload = true;
+
+ /* Are we subscribed? */
+ sev = v4l2_event_subscribed(fh, ev->type, ev->id);
+ if (sev == NULL)
+ return;
+
+ /* Increase event sequence number on fh. */
+ fh->sequence++;
+
+ /* Do we have any free events? */
+ if (sev->in_use == sev->elems) {
+ /* no, remove the oldest one */
+ kev = sev->events + sev_pos(sev, 0);
+ list_del(&kev->list);
+ sev->in_use--;
+ sev->first = sev_pos(sev, 1);
+ fh->navailable--;
+ if (sev->elems == 1) {
+ if (sev->replace) {
+ sev->replace(&kev->event, ev);
+ copy_payload = false;
+ }
+ } else if (sev->merge) {
+ struct v4l2_kevent *second_oldest =
+ sev->events + sev_pos(sev, 0);
+ sev->merge(&kev->event, &second_oldest->event);
+ }
+ }
+
+ /* Take one and fill it. */
+ kev = sev->events + sev_pos(sev, sev->in_use);
+ kev->event.type = ev->type;
+ if (copy_payload)
+ kev->event.u = ev->u;
+ kev->event.id = ev->id;
+ kev->event.timestamp = *ts;
+ kev->event.sequence = fh->sequence;
+ sev->in_use++;
+ list_add_tail(&kev->list, &fh->available);
+
+ fh->navailable++;
+
+ wake_up_all(&fh->wait);
+}
+
+void v4l2_event_queue(struct video_device *vdev, const struct v4l2_event *ev)
+{
+ struct v4l2_fh *fh;
+ unsigned long flags;
+ struct timespec timestamp;
+
+ ktime_get_ts(&timestamp);
+
+ spin_lock_irqsave(&vdev->fh_lock, flags);
+
+ list_for_each_entry(fh, &vdev->fh_list, list)
+ __v4l2_event_queue_fh(fh, ev, &timestamp);
+
+ spin_unlock_irqrestore(&vdev->fh_lock, flags);
+}
+EXPORT_SYMBOL_GPL(v4l2_event_queue);
+
+void v4l2_event_queue_fh(struct v4l2_fh *fh, const struct v4l2_event *ev)
+{
+ unsigned long flags;
+ struct timespec timestamp;
+
+ ktime_get_ts(&timestamp);
+
+ spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+ __v4l2_event_queue_fh(fh, ev, &timestamp);
+ spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+}
+EXPORT_SYMBOL_GPL(v4l2_event_queue_fh);
+
+int v4l2_event_pending(struct v4l2_fh *fh)
+{
+ return fh->navailable;
+}
+EXPORT_SYMBOL_GPL(v4l2_event_pending);
+
+static void ctrls_replace(struct v4l2_event *old, const struct v4l2_event *new)
+{
+ u32 old_changes = old->u.ctrl.changes;
+
+ old->u.ctrl = new->u.ctrl;
+ old->u.ctrl.changes |= old_changes;
+}
+
+static void ctrls_merge(const struct v4l2_event *old, struct v4l2_event *new)
+{
+ new->u.ctrl.changes |= old->u.ctrl.changes;
+}
+
+int v4l2_event_subscribe(struct v4l2_fh *fh,
+ struct v4l2_event_subscription *sub, unsigned elems)
+{
+ struct v4l2_subscribed_event *sev, *found_ev;
+ struct v4l2_ctrl *ctrl = NULL;
+ unsigned long flags;
+ unsigned i;
+
+ if (sub->type == V4L2_EVENT_ALL)
+ return -EINVAL;
+
+ if (elems < 1)
+ elems = 1;
+ if (sub->type == V4L2_EVENT_CTRL) {
+ ctrl = v4l2_ctrl_find(fh->ctrl_handler, sub->id);
+ if (ctrl == NULL)
+ return -EINVAL;
+ }
+
+ sev = kzalloc(sizeof(*sev) + sizeof(struct v4l2_kevent) * elems, GFP_KERNEL);
+ if (!sev)
+ return -ENOMEM;
+ for (i = 0; i < elems; i++)
+ sev->events[i].sev = sev;
+ sev->type = sub->type;
+ sev->id = sub->id;
+ sev->flags = sub->flags;
+ sev->fh = fh;
+ sev->elems = elems;
+ if (ctrl) {
+ sev->replace = ctrls_replace;
+ sev->merge = ctrls_merge;
+ }
+
+ spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+ found_ev = v4l2_event_subscribed(fh, sub->type, sub->id);
+ if (!found_ev)
+ 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)
+ kfree(sev);
+ else if (ctrl)
+ v4l2_ctrl_add_event(ctrl, sev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_event_subscribe);
+
+void v4l2_event_unsubscribe_all(struct v4l2_fh *fh)
+{
+ struct v4l2_event_subscription sub;
+ struct v4l2_subscribed_event *sev;
+ unsigned long flags;
+
+ do {
+ sev = NULL;
+
+ spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+ if (!list_empty(&fh->subscribed)) {
+ sev = list_first_entry(&fh->subscribed,
+ struct v4l2_subscribed_event, list);
+ sub.type = sev->type;
+ sub.id = sev->id;
+ }
+ spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+ if (sev)
+ v4l2_event_unsubscribe(fh, &sub);
+ } while (sev);
+}
+EXPORT_SYMBOL_GPL(v4l2_event_unsubscribe_all);
+
+int v4l2_event_unsubscribe(struct v4l2_fh *fh,
+ struct v4l2_event_subscription *sub)
+{
+ struct v4l2_subscribed_event *sev;
+ unsigned long flags;
+ int i;
+
+ if (sub->type == V4L2_EVENT_ALL) {
+ v4l2_event_unsubscribe_all(fh);
+ return 0;
+ }
+
+ 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);
+ }
+
+ spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+ if (sev && sev->type == V4L2_EVENT_CTRL) {
+ struct v4l2_ctrl *ctrl = v4l2_ctrl_find(fh->ctrl_handler, sev->id);
+
+ if (ctrl)
+ v4l2_ctrl_del_event(ctrl, sev);
+ }
+
+ kfree(sev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_event_unsubscribe);