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> |
35a24636 | 27 | #include <linux/export.h> |
1babcb46 SA |
28 | #include <media/v4l2-dev.h> |
29 | #include <media/v4l2-fh.h> | |
c3b5b024 SA |
30 | #include <media/v4l2-event.h> |
31 | #include <media/v4l2-ioctl.h> | |
1babcb46 | 32 | |
523f46d6 | 33 | void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev) |
1babcb46 SA |
34 | { |
35 | fh->vdev = vdev; | |
2d28b686 HV |
36 | /* Inherit from video_device. May be overridden by the driver. */ |
37 | fh->ctrl_handler = vdev->ctrl_handler; | |
1babcb46 SA |
38 | INIT_LIST_HEAD(&fh->list); |
39 | set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags); | |
fc5602be | 40 | fh->prio = V4L2_PRIORITY_UNSET; |
523f46d6 | 41 | init_waitqueue_head(&fh->wait); |
523f46d6 HV |
42 | INIT_LIST_HEAD(&fh->available); |
43 | INIT_LIST_HEAD(&fh->subscribed); | |
44 | fh->sequence = -1; | |
1babcb46 SA |
45 | } |
46 | EXPORT_SYMBOL_GPL(v4l2_fh_init); | |
47 | ||
48 | void v4l2_fh_add(struct v4l2_fh *fh) | |
49 | { | |
50 | unsigned long flags; | |
51 | ||
b1a873a3 HV |
52 | if (test_bit(V4L2_FL_USE_FH_PRIO, &fh->vdev->flags)) |
53 | v4l2_prio_open(fh->vdev->prio, &fh->prio); | |
1babcb46 SA |
54 | spin_lock_irqsave(&fh->vdev->fh_lock, flags); |
55 | list_add(&fh->list, &fh->vdev->fh_list); | |
56 | spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); | |
57 | } | |
58 | EXPORT_SYMBOL_GPL(v4l2_fh_add); | |
59 | ||
73cb4206 HV |
60 | int v4l2_fh_open(struct file *filp) |
61 | { | |
62 | struct video_device *vdev = video_devdata(filp); | |
63 | struct v4l2_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL); | |
64 | ||
65 | filp->private_data = fh; | |
66 | if (fh == NULL) | |
67 | return -ENOMEM; | |
68 | v4l2_fh_init(fh, vdev); | |
69 | v4l2_fh_add(fh); | |
70 | return 0; | |
71 | } | |
72 | EXPORT_SYMBOL_GPL(v4l2_fh_open); | |
73 | ||
1babcb46 SA |
74 | void v4l2_fh_del(struct v4l2_fh *fh) |
75 | { | |
76 | unsigned long flags; | |
77 | ||
78 | spin_lock_irqsave(&fh->vdev->fh_lock, flags); | |
79 | list_del_init(&fh->list); | |
80 | spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); | |
b1a873a3 HV |
81 | if (test_bit(V4L2_FL_USE_FH_PRIO, &fh->vdev->flags)) |
82 | v4l2_prio_close(fh->vdev->prio, fh->prio); | |
1babcb46 SA |
83 | } |
84 | EXPORT_SYMBOL_GPL(v4l2_fh_del); | |
85 | ||
86 | void v4l2_fh_exit(struct v4l2_fh *fh) | |
87 | { | |
88 | if (fh->vdev == NULL) | |
89 | return; | |
f1e393de | 90 | v4l2_event_unsubscribe_all(fh); |
6e239399 | 91 | fh->vdev = NULL; |
1babcb46 SA |
92 | } |
93 | EXPORT_SYMBOL_GPL(v4l2_fh_exit); | |
73cb4206 HV |
94 | |
95 | int v4l2_fh_release(struct file *filp) | |
96 | { | |
97 | struct v4l2_fh *fh = filp->private_data; | |
98 | ||
99 | if (fh) { | |
100 | v4l2_fh_del(fh); | |
101 | v4l2_fh_exit(fh); | |
102 | kfree(fh); | |
103 | } | |
104 | return 0; | |
105 | } | |
106 | EXPORT_SYMBOL_GPL(v4l2_fh_release); | |
dfddb244 HV |
107 | |
108 | int v4l2_fh_is_singular(struct v4l2_fh *fh) | |
109 | { | |
110 | unsigned long flags; | |
111 | int is_singular; | |
112 | ||
113 | if (fh == NULL || fh->vdev == NULL) | |
114 | return 0; | |
115 | spin_lock_irqsave(&fh->vdev->fh_lock, flags); | |
116 | is_singular = list_is_singular(&fh->list); | |
117 | spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); | |
118 | return is_singular; | |
119 | } | |
120 | EXPORT_SYMBOL_GPL(v4l2_fh_is_singular); |