6 * Copyright (C) 2009--2010 Nokia Corporation.
8 * Contact: Sakari Ailus <sakari.ailus@iki.fi>
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * version 2 as published by the Free Software Foundation.
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
25 #include <linux/bitops.h>
26 #include <linux/slab.h>
27 #include <linux/export.h>
28 #include <media/v4l2-dev.h>
29 #include <media/v4l2-fh.h>
30 #include <media/v4l2-event.h>
31 #include <media/v4l2-ioctl.h>
32 #include <media/v4l2-mc.h>
34 void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
37 /* Inherit from video_device. May be overridden by the driver. */
38 fh->ctrl_handler = vdev->ctrl_handler;
39 INIT_LIST_HEAD(&fh->list);
40 set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags);
42 * determine_valid_ioctls() does not know if struct v4l2_fh
43 * is used by this driver, but here we do. So enable the
46 set_bit(_IOC_NR(VIDIOC_G_PRIORITY), vdev->valid_ioctls);
47 set_bit(_IOC_NR(VIDIOC_S_PRIORITY), vdev->valid_ioctls);
48 fh->prio = V4L2_PRIORITY_UNSET;
49 init_waitqueue_head(&fh->wait);
50 INIT_LIST_HEAD(&fh->available);
51 INIT_LIST_HEAD(&fh->subscribed);
53 mutex_init(&fh->subscribe_lock);
55 EXPORT_SYMBOL_GPL(v4l2_fh_init);
57 void v4l2_fh_add(struct v4l2_fh *fh)
61 v4l2_prio_open(fh->vdev->prio, &fh->prio);
62 spin_lock_irqsave(&fh->vdev->fh_lock, flags);
63 list_add(&fh->list, &fh->vdev->fh_list);
64 spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
66 EXPORT_SYMBOL_GPL(v4l2_fh_add);
68 int v4l2_fh_open(struct file *filp)
70 struct video_device *vdev = video_devdata(filp);
71 struct v4l2_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL);
73 filp->private_data = fh;
76 v4l2_fh_init(fh, vdev);
80 EXPORT_SYMBOL_GPL(v4l2_fh_open);
82 void v4l2_fh_del(struct v4l2_fh *fh)
86 spin_lock_irqsave(&fh->vdev->fh_lock, flags);
87 list_del_init(&fh->list);
88 spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
89 v4l2_prio_close(fh->vdev->prio, fh->prio);
91 EXPORT_SYMBOL_GPL(v4l2_fh_del);
93 void v4l2_fh_exit(struct v4l2_fh *fh)
97 v4l_disable_media_source(fh->vdev);
98 v4l2_event_unsubscribe_all(fh);
99 mutex_destroy(&fh->subscribe_lock);
102 EXPORT_SYMBOL_GPL(v4l2_fh_exit);
104 int v4l2_fh_release(struct file *filp)
106 struct v4l2_fh *fh = filp->private_data;
112 filp->private_data = NULL;
116 EXPORT_SYMBOL_GPL(v4l2_fh_release);
118 int v4l2_fh_is_singular(struct v4l2_fh *fh)
123 if (fh == NULL || fh->vdev == NULL)
125 spin_lock_irqsave(&fh->vdev->fh_lock, flags);
126 is_singular = list_is_singular(&fh->list);
127 spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
130 EXPORT_SYMBOL_GPL(v4l2_fh_is_singular);