Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 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> |
Hans Verkuil | 73cb420 | 2011-01-08 09:36:04 -0300 | [diff] [blame] | 26 | #include <linux/slab.h> |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 27 | #include <media/v4l2-dev.h> |
| 28 | #include <media/v4l2-fh.h> |
Sakari Ailus | c3b5b02 | 2010-03-01 05:14:18 -0300 | [diff] [blame] | 29 | #include <media/v4l2-event.h> |
| 30 | #include <media/v4l2-ioctl.h> |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 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); |
Hans Verkuil | fc5602b | 2010-12-29 13:36:50 -0300 | [diff] [blame] | 37 | fh->prio = V4L2_PRIORITY_UNSET; |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 38 | |
Sakari Ailus | d3d7c96 | 2010-03-27 11:02:10 -0300 | [diff] [blame] | 39 | /* |
| 40 | * fh->events only needs to be initialized if the driver |
| 41 | * supports the VIDIOC_SUBSCRIBE_EVENT ioctl. |
| 42 | */ |
| 43 | if (vdev->ioctl_ops && vdev->ioctl_ops->vidioc_subscribe_event) |
| 44 | return v4l2_event_init(fh); |
| 45 | |
| 46 | fh->events = NULL; |
| 47 | |
| 48 | return 0; |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 49 | } |
| 50 | EXPORT_SYMBOL_GPL(v4l2_fh_init); |
| 51 | |
| 52 | void v4l2_fh_add(struct v4l2_fh *fh) |
| 53 | { |
| 54 | unsigned long flags; |
| 55 | |
Hans Verkuil | b1a873a | 2011-03-22 10:14:07 -0300 | [diff] [blame] | 56 | if (test_bit(V4L2_FL_USE_FH_PRIO, &fh->vdev->flags)) |
| 57 | v4l2_prio_open(fh->vdev->prio, &fh->prio); |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 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 | |
Hans Verkuil | 73cb420 | 2011-01-08 09:36:04 -0300 | [diff] [blame] | 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 | |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 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); |
Hans Verkuil | b1a873a | 2011-03-22 10:14:07 -0300 | [diff] [blame] | 85 | if (test_bit(V4L2_FL_USE_FH_PRIO, &fh->vdev->flags)) |
| 86 | v4l2_prio_close(fh->vdev->prio, fh->prio); |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 87 | } |
| 88 | EXPORT_SYMBOL_GPL(v4l2_fh_del); |
| 89 | |
| 90 | void v4l2_fh_exit(struct v4l2_fh *fh) |
| 91 | { |
| 92 | if (fh->vdev == NULL) |
| 93 | return; |
| 94 | |
| 95 | fh->vdev = NULL; |
Sakari Ailus | c3b5b02 | 2010-03-01 05:14:18 -0300 | [diff] [blame] | 96 | |
| 97 | v4l2_event_free(fh); |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 98 | } |
| 99 | EXPORT_SYMBOL_GPL(v4l2_fh_exit); |
Hans Verkuil | 73cb420 | 2011-01-08 09:36:04 -0300 | [diff] [blame] | 100 | |
| 101 | int v4l2_fh_release(struct file *filp) |
| 102 | { |
| 103 | struct v4l2_fh *fh = filp->private_data; |
| 104 | |
| 105 | if (fh) { |
| 106 | v4l2_fh_del(fh); |
| 107 | v4l2_fh_exit(fh); |
| 108 | kfree(fh); |
| 109 | } |
| 110 | return 0; |
| 111 | } |
| 112 | EXPORT_SYMBOL_GPL(v4l2_fh_release); |
Hans Verkuil | dfddb24 | 2011-01-08 09:38:02 -0300 | [diff] [blame] | 113 | |
| 114 | int v4l2_fh_is_singular(struct v4l2_fh *fh) |
| 115 | { |
| 116 | unsigned long flags; |
| 117 | int is_singular; |
| 118 | |
| 119 | if (fh == NULL || fh->vdev == NULL) |
| 120 | return 0; |
| 121 | spin_lock_irqsave(&fh->vdev->fh_lock, flags); |
| 122 | is_singular = list_is_singular(&fh->list); |
| 123 | spin_unlock_irqrestore(&fh->vdev->fh_lock, flags); |
| 124 | return is_singular; |
| 125 | } |
| 126 | EXPORT_SYMBOL_GPL(v4l2_fh_is_singular); |