Commit | Line | Data |
---|---|---|
1babcb46 SA |
1 | /* |
2 | * v4l2-fh.c | |
3 | * | |
4 | * V4L2 file handles. | |
5 | * | |
6 | * Copyright (C) 2009--2010 Nokia Corporation. | |
7 | * | |
8 | * Contact: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com> | |
9 | * | |
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. | |
13 | * | |
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. | |
18 | * | |
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 | |
22 | * 02110-1301 USA | |
23 | */ | |
24 | ||
25 | #include <linux/bitops.h> | |
73cb4206 | 26 | #include <linux/slab.h> |
1babcb46 SA |
27 | #include <media/v4l2-dev.h> |
28 | #include <media/v4l2-fh.h> | |
c3b5b024 SA |
29 | #include <media/v4l2-event.h> |
30 | #include <media/v4l2-ioctl.h> | |
1babcb46 SA |
31 | |
32 | int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev) | |
33 | { | |
34 | fh->vdev = vdev; | |
35 | INIT_LIST_HEAD(&fh->list); | |
36 | set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags); | |
fc5602be HV |
37 | fh->prio = V4L2_PRIORITY_UNSET; |
38 | BUG_ON(vdev->prio == NULL); | |
1babcb46 | 39 | |
d3d7c963 SA |
40 | /* |
41 | * fh->events only needs to be initialized if the driver | |
42 | * supports the VIDIOC_SUBSCRIBE_EVENT ioctl. | |
43 | */ | |
44 | if (vdev->ioctl_ops && vdev->ioctl_ops->vidioc_subscribe_event) | |
45 | return v4l2_event_init(fh); | |
46 | ||
47 | fh->events = NULL; | |
48 | ||
49 | return 0; | |
1babcb46 SA |
50 | } |
51 | EXPORT_SYMBOL_GPL(v4l2_fh_init); | |
52 | ||
53 | void v4l2_fh_add(struct v4l2_fh *fh) | |
54 | { | |
55 | unsigned long flags; | |
56 | ||
fc5602be | 57 | v4l2_prio_open(fh->vdev->prio, &fh->prio); |
1babcb46 SA |
58 | spin_lock_irqsave(&fh->vdev->fh_lock, flags); |
59 | list_add(&fh->list, &fh->vdev->fh_list); | |
60 | spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); | |
61 | } | |
62 | EXPORT_SYMBOL_GPL(v4l2_fh_add); | |
63 | ||
73cb4206 HV |
64 | int v4l2_fh_open(struct file *filp) |
65 | { | |
66 | struct video_device *vdev = video_devdata(filp); | |
67 | struct v4l2_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL); | |
68 | ||
69 | filp->private_data = fh; | |
70 | if (fh == NULL) | |
71 | return -ENOMEM; | |
72 | v4l2_fh_init(fh, vdev); | |
73 | v4l2_fh_add(fh); | |
74 | return 0; | |
75 | } | |
76 | EXPORT_SYMBOL_GPL(v4l2_fh_open); | |
77 | ||
1babcb46 SA |
78 | void v4l2_fh_del(struct v4l2_fh *fh) |
79 | { | |
80 | unsigned long flags; | |
81 | ||
82 | spin_lock_irqsave(&fh->vdev->fh_lock, flags); | |
83 | list_del_init(&fh->list); | |
84 | spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); | |
fc5602be | 85 | v4l2_prio_close(fh->vdev->prio, fh->prio); |
1babcb46 SA |
86 | } |
87 | EXPORT_SYMBOL_GPL(v4l2_fh_del); | |
88 | ||
89 | void v4l2_fh_exit(struct v4l2_fh *fh) | |
90 | { | |
91 | if (fh->vdev == NULL) | |
92 | return; | |
93 | ||
94 | fh->vdev = NULL; | |
c3b5b024 SA |
95 | |
96 | v4l2_event_free(fh); | |
1babcb46 SA |
97 | } |
98 | EXPORT_SYMBOL_GPL(v4l2_fh_exit); | |
73cb4206 HV |
99 | |
100 | int v4l2_fh_release(struct file *filp) | |
101 | { | |
102 | struct v4l2_fh *fh = filp->private_data; | |
103 | ||
104 | if (fh) { | |
105 | v4l2_fh_del(fh); | |
106 | v4l2_fh_exit(fh); | |
107 | kfree(fh); | |
108 | } | |
109 | return 0; | |
110 | } | |
111 | EXPORT_SYMBOL_GPL(v4l2_fh_release); | |
dfddb244 HV |
112 | |
113 | int v4l2_fh_is_singular(struct v4l2_fh *fh) | |
114 | { | |
115 | unsigned long flags; | |
116 | int is_singular; | |
117 | ||
118 | if (fh == NULL || fh->vdev == NULL) | |
119 | return 0; | |
120 | spin_lock_irqsave(&fh->vdev->fh_lock, flags); | |
121 | is_singular = list_is_singular(&fh->list); | |
122 | spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); | |
123 | return is_singular; | |
124 | } | |
125 | EXPORT_SYMBOL_GPL(v4l2_fh_is_singular); |