1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
|
/*
* v4l2-fh.c
*
* V4L2 file handles.
*
* Copyright (C) 2009--2010 Nokia Corporation.
*
* Contact: Sakari Ailus <sakari.ailus@iki.fi>
*
* 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 <linux/bitops.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-event.h>
#include <media/v4l2-ioctl.h>
void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
{
fh->vdev = vdev;
/* Inherit from video_device. May be overridden by the driver. */
fh->ctrl_handler = vdev->ctrl_handler;
INIT_LIST_HEAD(&fh->list);
set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags);
/*
* determine_valid_ioctls() does not know if struct v4l2_fh
* is used by this driver, but here we do. So enable the
* prio ioctls here.
*/
set_bit(_IOC_NR(VIDIOC_G_PRIORITY), vdev->valid_ioctls);
set_bit(_IOC_NR(VIDIOC_S_PRIORITY), vdev->valid_ioctls);
fh->prio = V4L2_PRIORITY_UNSET;
init_waitqueue_head(&fh->wait);
INIT_LIST_HEAD(&fh->available);
INIT_LIST_HEAD(&fh->subscribed);
fh->sequence = -1;
mutex_init(&fh->subscribe_lock);
}
EXPORT_SYMBOL_GPL(v4l2_fh_init);
void v4l2_fh_add(struct v4l2_fh *fh)
{
unsigned long flags;
v4l2_prio_open(fh->vdev->prio, &fh->prio);
spin_lock_irqsave(&fh->vdev->fh_lock, flags);
list_add(&fh->list, &fh->vdev->fh_list);
spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
}
EXPORT_SYMBOL_GPL(v4l2_fh_add);
int v4l2_fh_open(struct file *filp)
{
struct video_device *vdev = video_devdata(filp);
struct v4l2_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL);
filp->private_data = fh;
if (fh == NULL)
return -ENOMEM;
v4l2_fh_init(fh, vdev);
v4l2_fh_add(fh);
return 0;
}
EXPORT_SYMBOL_GPL(v4l2_fh_open);
void v4l2_fh_del(struct v4l2_fh *fh)
{
unsigned long flags;
spin_lock_irqsave(&fh->vdev->fh_lock, flags);
list_del_init(&fh->list);
spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
v4l2_prio_close(fh->vdev->prio, fh->prio);
}
EXPORT_SYMBOL_GPL(v4l2_fh_del);
void v4l2_fh_exit(struct v4l2_fh *fh)
{
if (fh->vdev == NULL)
return;
v4l2_event_unsubscribe_all(fh);
mutex_destroy(&fh->subscribe_lock);
fh->vdev = NULL;
}
EXPORT_SYMBOL_GPL(v4l2_fh_exit);
int v4l2_fh_release(struct file *filp)
{
struct v4l2_fh *fh = filp->private_data;
if (fh) {
v4l2_fh_del(fh);
v4l2_fh_exit(fh);
kfree(fh);
filp->private_data = NULL;
}
return 0;
}
EXPORT_SYMBOL_GPL(v4l2_fh_release);
int v4l2_fh_is_singular(struct v4l2_fh *fh)
{
unsigned long flags;
int is_singular;
if (fh == NULL || fh->vdev == NULL)
return 0;
spin_lock_irqsave(&fh->vdev->fh_lock, flags);
is_singular = list_is_singular(&fh->list);
spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
return is_singular;
}
EXPORT_SYMBOL_GPL(v4l2_fh_is_singular);
|
