6 * Copyright (C) 2009--2010 Nokia Corporation.
8 * Contact: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
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 <media/v4l2-dev.h>
28 #include <media/v4l2-fh.h>
29 #include <media/v4l2-event.h>
30 #include <media/v4l2-ioctl.h>
32 int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
35 /* Inherit from video_device. May be overridden by the driver. */
36 fh->ctrl_handler = vdev->ctrl_handler;
37 INIT_LIST_HEAD(&fh->list);
38 set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags);
39 fh->prio = V4L2_PRIORITY_UNSET;
42 * fh->events only needs to be initialized if the driver
43 * supports the VIDIOC_SUBSCRIBE_EVENT ioctl.
45 if (vdev->ioctl_ops && vdev->ioctl_ops->vidioc_subscribe_event)
46 return v4l2_event_init(fh);
52 EXPORT_SYMBOL_GPL(v4l2_fh_init);
54 void v4l2_fh_add(struct v4l2_fh *fh)
58 if (test_bit(V4L2_FL_USE_FH_PRIO, &fh->vdev->flags))
59 v4l2_prio_open(fh->vdev->prio, &fh->prio);
60 spin_lock_irqsave(&fh->vdev->fh_lock, flags);
61 list_add(&fh->list, &fh->vdev->fh_list);
62 spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
64 EXPORT_SYMBOL_GPL(v4l2_fh_add);
66 int v4l2_fh_open(struct file *filp)
68 struct video_device *vdev = video_devdata(filp);
69 struct v4l2_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL);
71 filp->private_data = fh;
74 v4l2_fh_init(fh, vdev);
78 EXPORT_SYMBOL_GPL(v4l2_fh_open);
80 void v4l2_fh_del(struct v4l2_fh *fh)
84 spin_lock_irqsave(&fh->vdev->fh_lock, flags);
85 list_del_init(&fh->list);
86 spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
87 if (test_bit(V4L2_FL_USE_FH_PRIO, &fh->vdev->flags))
88 v4l2_prio_close(fh->vdev->prio, fh->prio);
90 EXPORT_SYMBOL_GPL(v4l2_fh_del);
92 void v4l2_fh_exit(struct v4l2_fh *fh)
101 EXPORT_SYMBOL_GPL(v4l2_fh_exit);
103 int v4l2_fh_release(struct file *filp)
105 struct v4l2_fh *fh = filp->private_data;
114 EXPORT_SYMBOL_GPL(v4l2_fh_release);
116 int v4l2_fh_is_singular(struct v4l2_fh *fh)
121 if (fh == NULL || fh->vdev == NULL)
123 spin_lock_irqsave(&fh->vdev->fh_lock, flags);
124 is_singular = list_is_singular(&fh->list);
125 spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
128 EXPORT_SYMBOL_GPL(v4l2_fh_is_singular);