Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 1 | /* |
| 2 | * Video capture interface for Linux version 2 |
| 3 | * |
| 4 | * A generic video device interface for the LINUX operating system |
| 5 | * using a set of device structures/vectors for low level operations. |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version |
| 10 | * 2 of the License, or (at your option) any later version. |
| 11 | * |
Alan Cox | d9b0144 | 2008-10-27 15:13:47 -0300 | [diff] [blame] | 12 | * Authors: Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1) |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 13 | * Mauro Carvalho Chehab <mchehab@infradead.org> (version 2) |
| 14 | * |
| 15 | * Fixes: 20000516 Claudio Matsuoka <claudio@conectiva.com> |
| 16 | * - Added procfs support |
| 17 | */ |
| 18 | |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/types.h> |
| 21 | #include <linux/kernel.h> |
| 22 | #include <linux/mm.h> |
| 23 | #include <linux/string.h> |
| 24 | #include <linux/errno.h> |
| 25 | #include <linux/init.h> |
| 26 | #include <linux/kmod.h> |
| 27 | #include <linux/slab.h> |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 28 | #include <asm/uaccess.h> |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 29 | |
| 30 | #include <media/v4l2-common.h> |
Hans Verkuil | 9bea351 | 2008-12-23 07:35:17 -0300 | [diff] [blame] | 31 | #include <media/v4l2-device.h> |
Hans Verkuil | bec4366 | 2008-12-30 06:58:20 -0300 | [diff] [blame] | 32 | #include <media/v4l2-ioctl.h> |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 33 | |
| 34 | #define VIDEO_NUM_DEVICES 256 |
| 35 | #define VIDEO_NAME "video4linux" |
| 36 | |
| 37 | /* |
| 38 | * sysfs stuff |
| 39 | */ |
| 40 | |
| 41 | static ssize_t show_index(struct device *cd, |
| 42 | struct device_attribute *attr, char *buf) |
| 43 | { |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 44 | struct video_device *vdev = to_video_device(cd); |
Hans Verkuil | bfa8a27 | 2008-08-23 07:48:38 -0300 | [diff] [blame] | 45 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 46 | return sprintf(buf, "%i\n", vdev->index); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 47 | } |
| 48 | |
| 49 | static ssize_t show_name(struct device *cd, |
| 50 | struct device_attribute *attr, char *buf) |
| 51 | { |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 52 | struct video_device *vdev = to_video_device(cd); |
Hans Verkuil | bfa8a27 | 2008-08-23 07:48:38 -0300 | [diff] [blame] | 53 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 54 | return sprintf(buf, "%.*s\n", (int)sizeof(vdev->name), vdev->name); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 55 | } |
| 56 | |
| 57 | static struct device_attribute video_device_attrs[] = { |
| 58 | __ATTR(name, S_IRUGO, show_name, NULL), |
| 59 | __ATTR(index, S_IRUGO, show_index, NULL), |
| 60 | __ATTR_NULL |
| 61 | }; |
| 62 | |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 63 | /* |
| 64 | * Active devices |
| 65 | */ |
| 66 | static struct video_device *video_device[VIDEO_NUM_DEVICES]; |
| 67 | static DEFINE_MUTEX(videodev_lock); |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 68 | static DECLARE_BITMAP(devnode_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES); |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 69 | |
Hans Verkuil | 5062cb7 | 2009-09-07 03:40:24 -0300 | [diff] [blame] | 70 | /* Device node utility functions */ |
| 71 | |
| 72 | /* Note: these utility functions all assume that vfl_type is in the range |
| 73 | [0, VFL_TYPE_MAX-1]. */ |
| 74 | |
| 75 | #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES |
| 76 | /* Return the bitmap corresponding to vfl_type. */ |
| 77 | static inline unsigned long *devnode_bits(int vfl_type) |
| 78 | { |
| 79 | /* Any types not assigned to fixed minor ranges must be mapped to |
| 80 | one single bitmap for the purposes of finding a free node number |
| 81 | since all those unassigned types use the same minor range. */ |
Hans Verkuil | 226c0ee | 2010-08-06 12:48:00 -0300 | [diff] [blame] | 82 | int idx = (vfl_type > VFL_TYPE_RADIO) ? VFL_TYPE_MAX - 1 : vfl_type; |
Hans Verkuil | 5062cb7 | 2009-09-07 03:40:24 -0300 | [diff] [blame] | 83 | |
| 84 | return devnode_nums[idx]; |
| 85 | } |
| 86 | #else |
| 87 | /* Return the bitmap corresponding to vfl_type. */ |
| 88 | static inline unsigned long *devnode_bits(int vfl_type) |
| 89 | { |
| 90 | return devnode_nums[vfl_type]; |
| 91 | } |
| 92 | #endif |
| 93 | |
| 94 | /* Mark device node number vdev->num as used */ |
| 95 | static inline void devnode_set(struct video_device *vdev) |
| 96 | { |
| 97 | set_bit(vdev->num, devnode_bits(vdev->vfl_type)); |
| 98 | } |
| 99 | |
| 100 | /* Mark device node number vdev->num as unused */ |
| 101 | static inline void devnode_clear(struct video_device *vdev) |
| 102 | { |
| 103 | clear_bit(vdev->num, devnode_bits(vdev->vfl_type)); |
| 104 | } |
| 105 | |
| 106 | /* Try to find a free device node number in the range [from, to> */ |
| 107 | static inline int devnode_find(struct video_device *vdev, int from, int to) |
| 108 | { |
| 109 | return find_next_zero_bit(devnode_bits(vdev->vfl_type), to, from); |
| 110 | } |
| 111 | |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 112 | struct video_device *video_device_alloc(void) |
| 113 | { |
Hans Verkuil | bfa8a27 | 2008-08-23 07:48:38 -0300 | [diff] [blame] | 114 | return kzalloc(sizeof(struct video_device), GFP_KERNEL); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 115 | } |
| 116 | EXPORT_SYMBOL(video_device_alloc); |
| 117 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 118 | void video_device_release(struct video_device *vdev) |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 119 | { |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 120 | kfree(vdev); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 121 | } |
| 122 | EXPORT_SYMBOL(video_device_release); |
| 123 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 124 | void video_device_release_empty(struct video_device *vdev) |
Hans Verkuil | f9e86b5 | 2008-08-23 05:47:41 -0300 | [diff] [blame] | 125 | { |
| 126 | /* Do nothing */ |
| 127 | /* Only valid when the video_device struct is a static. */ |
| 128 | } |
| 129 | EXPORT_SYMBOL(video_device_release_empty); |
| 130 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 131 | static inline void video_get(struct video_device *vdev) |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 132 | { |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 133 | get_device(&vdev->dev); |
| 134 | } |
| 135 | |
| 136 | static inline void video_put(struct video_device *vdev) |
| 137 | { |
| 138 | put_device(&vdev->dev); |
| 139 | } |
| 140 | |
| 141 | /* Called when the last user of the video device exits. */ |
| 142 | static void v4l2_device_release(struct device *cd) |
| 143 | { |
| 144 | struct video_device *vdev = to_video_device(cd); |
Hans Verkuil | bedf8bc | 2011-03-12 06:37:19 -0300 | [diff] [blame] | 145 | struct v4l2_device *v4l2_dev = vdev->v4l2_dev; |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 146 | |
| 147 | mutex_lock(&videodev_lock); |
Guennadi Liakhovetski | 1fc2b5f | 2011-12-06 05:33:03 -0300 | [diff] [blame] | 148 | if (WARN_ON(video_device[vdev->minor] != vdev)) { |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 149 | /* should not happen */ |
Guennadi Liakhovetski | 1fc2b5f | 2011-12-06 05:33:03 -0300 | [diff] [blame] | 150 | mutex_unlock(&videodev_lock); |
Hans Verkuil | 6ea9a18 | 2008-08-30 09:40:47 -0300 | [diff] [blame] | 151 | return; |
| 152 | } |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 153 | |
| 154 | /* Free up this device for reuse */ |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 155 | video_device[vdev->minor] = NULL; |
| 156 | |
| 157 | /* Delete the cdev on this minor as well */ |
| 158 | cdev_del(vdev->cdev); |
| 159 | /* Just in case some driver tries to access this from |
| 160 | the release() callback. */ |
| 161 | vdev->cdev = NULL; |
| 162 | |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 163 | /* Mark device node number as free */ |
Hans Verkuil | 5062cb7 | 2009-09-07 03:40:24 -0300 | [diff] [blame] | 164 | devnode_clear(vdev); |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 165 | |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 166 | mutex_unlock(&videodev_lock); |
| 167 | |
Laurent Pinchart | c064b8e | 2011-06-15 05:20:34 -0300 | [diff] [blame] | 168 | #if defined(CONFIG_MEDIA_CONTROLLER) |
Guennadi Liakhovetski | 1fc2b5f | 2011-12-06 05:33:03 -0300 | [diff] [blame] | 169 | if (v4l2_dev && v4l2_dev->mdev && |
Laurent Pinchart | c064b8e | 2011-06-15 05:20:34 -0300 | [diff] [blame] | 170 | vdev->vfl_type != VFL_TYPE_SUBDEV) |
| 171 | media_device_unregister_entity(&vdev->entity); |
| 172 | #endif |
| 173 | |
Hans Verkuil | 8280b66 | 2011-09-06 10:23:18 -0300 | [diff] [blame] | 174 | /* Do not call v4l2_device_put if there is no release callback set. |
| 175 | * Drivers that have no v4l2_device release callback might free the |
| 176 | * v4l2_dev instance in the video_device release callback below, so we |
| 177 | * must perform this check here. |
| 178 | * |
| 179 | * TODO: In the long run all drivers that use v4l2_device should use the |
| 180 | * v4l2_device release callback. This check will then be unnecessary. |
| 181 | */ |
Antonio Ospite | e58fced | 2011-10-12 17:59:26 -0300 | [diff] [blame] | 182 | if (v4l2_dev && v4l2_dev->release == NULL) |
Hans Verkuil | 8280b66 | 2011-09-06 10:23:18 -0300 | [diff] [blame] | 183 | v4l2_dev = NULL; |
| 184 | |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 185 | /* Release video_device and perform other |
| 186 | cleanups as needed. */ |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 187 | vdev->release(vdev); |
Hans Verkuil | bedf8bc | 2011-03-12 06:37:19 -0300 | [diff] [blame] | 188 | |
| 189 | /* Decrease v4l2_device refcount */ |
| 190 | if (v4l2_dev) |
| 191 | v4l2_device_put(v4l2_dev); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 192 | } |
| 193 | |
| 194 | static struct class video_class = { |
| 195 | .name = VIDEO_NAME, |
| 196 | .dev_attrs = video_device_attrs, |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 197 | }; |
| 198 | |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 199 | struct video_device *video_devdata(struct file *file) |
| 200 | { |
| 201 | return video_device[iminor(file->f_path.dentry->d_inode)]; |
| 202 | } |
| 203 | EXPORT_SYMBOL(video_devdata); |
| 204 | |
Hans Verkuil | 0226549 | 2010-12-29 10:05:02 -0300 | [diff] [blame] | 205 | |
| 206 | /* Priority handling */ |
| 207 | |
| 208 | static inline bool prio_is_valid(enum v4l2_priority prio) |
| 209 | { |
| 210 | return prio == V4L2_PRIORITY_BACKGROUND || |
| 211 | prio == V4L2_PRIORITY_INTERACTIVE || |
| 212 | prio == V4L2_PRIORITY_RECORD; |
| 213 | } |
| 214 | |
| 215 | void v4l2_prio_init(struct v4l2_prio_state *global) |
| 216 | { |
| 217 | memset(global, 0, sizeof(*global)); |
| 218 | } |
| 219 | EXPORT_SYMBOL(v4l2_prio_init); |
| 220 | |
| 221 | int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local, |
| 222 | enum v4l2_priority new) |
| 223 | { |
| 224 | if (!prio_is_valid(new)) |
| 225 | return -EINVAL; |
| 226 | if (*local == new) |
| 227 | return 0; |
| 228 | |
| 229 | atomic_inc(&global->prios[new]); |
| 230 | if (prio_is_valid(*local)) |
| 231 | atomic_dec(&global->prios[*local]); |
| 232 | *local = new; |
| 233 | return 0; |
| 234 | } |
| 235 | EXPORT_SYMBOL(v4l2_prio_change); |
| 236 | |
| 237 | void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local) |
| 238 | { |
| 239 | v4l2_prio_change(global, local, V4L2_PRIORITY_DEFAULT); |
| 240 | } |
| 241 | EXPORT_SYMBOL(v4l2_prio_open); |
| 242 | |
| 243 | void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local) |
| 244 | { |
| 245 | if (prio_is_valid(local)) |
| 246 | atomic_dec(&global->prios[local]); |
| 247 | } |
| 248 | EXPORT_SYMBOL(v4l2_prio_close); |
| 249 | |
| 250 | enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global) |
| 251 | { |
| 252 | if (atomic_read(&global->prios[V4L2_PRIORITY_RECORD]) > 0) |
| 253 | return V4L2_PRIORITY_RECORD; |
| 254 | if (atomic_read(&global->prios[V4L2_PRIORITY_INTERACTIVE]) > 0) |
| 255 | return V4L2_PRIORITY_INTERACTIVE; |
| 256 | if (atomic_read(&global->prios[V4L2_PRIORITY_BACKGROUND]) > 0) |
| 257 | return V4L2_PRIORITY_BACKGROUND; |
| 258 | return V4L2_PRIORITY_UNSET; |
| 259 | } |
| 260 | EXPORT_SYMBOL(v4l2_prio_max); |
| 261 | |
| 262 | int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local) |
| 263 | { |
| 264 | return (local < v4l2_prio_max(global)) ? -EBUSY : 0; |
| 265 | } |
| 266 | EXPORT_SYMBOL(v4l2_prio_check); |
| 267 | |
| 268 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 269 | static ssize_t v4l2_read(struct file *filp, char __user *buf, |
| 270 | size_t sz, loff_t *off) |
| 271 | { |
| 272 | struct video_device *vdev = video_devdata(filp); |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 273 | int ret = -ENODEV; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 274 | |
| 275 | if (!vdev->fops->read) |
| 276 | return -EINVAL; |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 277 | if (vdev->lock && mutex_lock_interruptible(vdev->lock)) |
| 278 | return -ERESTARTSYS; |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 279 | if (video_is_registered(vdev)) |
| 280 | ret = vdev->fops->read(filp, buf, sz, off); |
| 281 | if (vdev->lock) |
| 282 | mutex_unlock(vdev->lock); |
| 283 | return ret; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 284 | } |
| 285 | |
| 286 | static ssize_t v4l2_write(struct file *filp, const char __user *buf, |
| 287 | size_t sz, loff_t *off) |
| 288 | { |
| 289 | struct video_device *vdev = video_devdata(filp); |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 290 | int ret = -ENODEV; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 291 | |
| 292 | if (!vdev->fops->write) |
| 293 | return -EINVAL; |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 294 | if (vdev->lock && mutex_lock_interruptible(vdev->lock)) |
| 295 | return -ERESTARTSYS; |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 296 | if (video_is_registered(vdev)) |
| 297 | ret = vdev->fops->write(filp, buf, sz, off); |
| 298 | if (vdev->lock) |
| 299 | mutex_unlock(vdev->lock); |
| 300 | return ret; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 301 | } |
| 302 | |
| 303 | static unsigned int v4l2_poll(struct file *filp, struct poll_table_struct *poll) |
| 304 | { |
| 305 | struct video_device *vdev = video_devdata(filp); |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 306 | int ret = POLLERR | POLLHUP; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 307 | |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 308 | if (!vdev->fops->poll) |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 309 | return DEFAULT_POLLMASK; |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 310 | if (vdev->lock) |
| 311 | mutex_lock(vdev->lock); |
| 312 | if (video_is_registered(vdev)) |
| 313 | ret = vdev->fops->poll(filp, poll); |
| 314 | if (vdev->lock) |
| 315 | mutex_unlock(vdev->lock); |
| 316 | return ret; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 317 | } |
| 318 | |
Arnd Bergmann | 86a5ef7 | 2010-07-04 00:15:09 +0200 | [diff] [blame] | 319 | static long v4l2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 320 | { |
| 321 | struct video_device *vdev = video_devdata(filp); |
Mauro Carvalho Chehab | 7242063 | 2010-10-09 16:43:40 -0300 | [diff] [blame] | 322 | int ret = -ENODEV; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 323 | |
Arnd Bergmann | 86a5ef7 | 2010-07-04 00:15:09 +0200 | [diff] [blame] | 324 | if (vdev->fops->unlocked_ioctl) { |
Hans Verkuil | 8ab75e3 | 2012-05-10 02:51:31 -0300 | [diff] [blame^] | 325 | bool locked = false; |
| 326 | |
| 327 | if (vdev->lock) { |
| 328 | /* always lock unless the cmd is marked as "don't use lock" */ |
| 329 | locked = !v4l2_is_known_ioctl(cmd) || |
| 330 | !test_bit(_IOC_NR(cmd), vdev->dont_use_lock); |
| 331 | |
| 332 | if (locked && mutex_lock_interruptible(vdev->lock)) |
| 333 | return -ERESTARTSYS; |
| 334 | } |
Mauro Carvalho Chehab | 7242063 | 2010-10-09 16:43:40 -0300 | [diff] [blame] | 335 | if (video_is_registered(vdev)) |
| 336 | ret = vdev->fops->unlocked_ioctl(filp, cmd, arg); |
Hans Verkuil | 8ab75e3 | 2012-05-10 02:51:31 -0300 | [diff] [blame^] | 337 | if (locked) |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 338 | mutex_unlock(vdev->lock); |
Arnd Bergmann | 86a5ef7 | 2010-07-04 00:15:09 +0200 | [diff] [blame] | 339 | } else if (vdev->fops->ioctl) { |
Hans Verkuil | 879aa24 | 2010-11-26 06:47:28 -0300 | [diff] [blame] | 340 | /* This code path is a replacement for the BKL. It is a major |
| 341 | * hack but it will have to do for those drivers that are not |
| 342 | * yet converted to use unlocked_ioctl. |
| 343 | * |
| 344 | * There are two options: if the driver implements struct |
| 345 | * v4l2_device, then the lock defined there is used to |
| 346 | * serialize the ioctls. Otherwise the v4l2 core lock defined |
| 347 | * below is used. This lock is really bad since it serializes |
| 348 | * completely independent devices. |
| 349 | * |
| 350 | * Both variants suffer from the same problem: if the driver |
| 351 | * sleeps, then it blocks all ioctls since the lock is still |
| 352 | * held. This is very common for VIDIOC_DQBUF since that |
| 353 | * normally waits for a frame to arrive. As a result any other |
| 354 | * ioctl calls will proceed very, very slowly since each call |
| 355 | * will have to wait for the VIDIOC_QBUF to finish. Things that |
| 356 | * should take 0.01s may now take 10-20 seconds. |
| 357 | * |
| 358 | * The workaround is to *not* take the lock for VIDIOC_DQBUF. |
| 359 | * This actually works OK for videobuf-based drivers, since |
| 360 | * videobuf will take its own internal lock. |
| 361 | */ |
Arnd Bergmann | 0edf2e5 | 2010-10-27 09:30:32 -0300 | [diff] [blame] | 362 | static DEFINE_MUTEX(v4l2_ioctl_mutex); |
Hans Verkuil | 879aa24 | 2010-11-26 06:47:28 -0300 | [diff] [blame] | 363 | struct mutex *m = vdev->v4l2_dev ? |
| 364 | &vdev->v4l2_dev->ioctl_lock : &v4l2_ioctl_mutex; |
Arnd Bergmann | 0edf2e5 | 2010-10-27 09:30:32 -0300 | [diff] [blame] | 365 | |
Hans Verkuil | 879aa24 | 2010-11-26 06:47:28 -0300 | [diff] [blame] | 366 | if (cmd != VIDIOC_DQBUF && mutex_lock_interruptible(m)) |
| 367 | return -ERESTARTSYS; |
Mauro Carvalho Chehab | 7242063 | 2010-10-09 16:43:40 -0300 | [diff] [blame] | 368 | if (video_is_registered(vdev)) |
| 369 | ret = vdev->fops->ioctl(filp, cmd, arg); |
Hans Verkuil | 879aa24 | 2010-11-26 06:47:28 -0300 | [diff] [blame] | 370 | if (cmd != VIDIOC_DQBUF) |
| 371 | mutex_unlock(m); |
Arnd Bergmann | 86a5ef7 | 2010-07-04 00:15:09 +0200 | [diff] [blame] | 372 | } else |
| 373 | ret = -ENOTTY; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 374 | |
Arnd Bergmann | 86a5ef7 | 2010-07-04 00:15:09 +0200 | [diff] [blame] | 375 | return ret; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 376 | } |
| 377 | |
Bob Liu | ecc6517 | 2011-05-06 05:20:09 -0300 | [diff] [blame] | 378 | #ifdef CONFIG_MMU |
| 379 | #define v4l2_get_unmapped_area NULL |
| 380 | #else |
| 381 | static unsigned long v4l2_get_unmapped_area(struct file *filp, |
| 382 | unsigned long addr, unsigned long len, unsigned long pgoff, |
| 383 | unsigned long flags) |
| 384 | { |
| 385 | struct video_device *vdev = video_devdata(filp); |
| 386 | |
| 387 | if (!vdev->fops->get_unmapped_area) |
| 388 | return -ENOSYS; |
| 389 | if (!video_is_registered(vdev)) |
| 390 | return -ENODEV; |
| 391 | return vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags); |
| 392 | } |
| 393 | #endif |
| 394 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 395 | static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm) |
| 396 | { |
| 397 | struct video_device *vdev = video_devdata(filp); |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 398 | int ret = -ENODEV; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 399 | |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 400 | if (!vdev->fops->mmap) |
| 401 | return ret; |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 402 | if (vdev->lock && mutex_lock_interruptible(vdev->lock)) |
| 403 | return -ERESTARTSYS; |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 404 | if (video_is_registered(vdev)) |
| 405 | ret = vdev->fops->mmap(filp, vm); |
| 406 | if (vdev->lock) |
| 407 | mutex_unlock(vdev->lock); |
| 408 | return ret; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 409 | } |
| 410 | |
| 411 | /* Override for the open function */ |
| 412 | static int v4l2_open(struct inode *inode, struct file *filp) |
| 413 | { |
| 414 | struct video_device *vdev; |
Hans Verkuil | 65d9ff9 | 2009-03-29 20:19:38 -0300 | [diff] [blame] | 415 | int ret = 0; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 416 | |
| 417 | /* Check if the video device is available */ |
| 418 | mutex_lock(&videodev_lock); |
| 419 | vdev = video_devdata(filp); |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 420 | /* return ENODEV if the video device has already been removed. */ |
Hans Verkuil | ca9afe6 | 2010-11-26 06:54:53 -0300 | [diff] [blame] | 421 | if (vdev == NULL || !video_is_registered(vdev)) { |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 422 | mutex_unlock(&videodev_lock); |
| 423 | return -ENODEV; |
| 424 | } |
| 425 | /* and increase the device refcount */ |
| 426 | video_get(vdev); |
| 427 | mutex_unlock(&videodev_lock); |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 428 | if (vdev->fops->open) { |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 429 | if (vdev->lock && mutex_lock_interruptible(vdev->lock)) { |
| 430 | ret = -ERESTARTSYS; |
| 431 | goto err; |
| 432 | } |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 433 | if (video_is_registered(vdev)) |
| 434 | ret = vdev->fops->open(filp); |
| 435 | else |
| 436 | ret = -ENODEV; |
| 437 | if (vdev->lock) |
| 438 | mutex_unlock(vdev->lock); |
| 439 | } |
Hans Verkuil | 65d9ff9 | 2009-03-29 20:19:38 -0300 | [diff] [blame] | 440 | |
Hans Verkuil | 2877842 | 2010-11-26 06:43:51 -0300 | [diff] [blame] | 441 | err: |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 442 | /* decrease the refcount in case of an error */ |
Laurent Pinchart | c064b8e | 2011-06-15 05:20:34 -0300 | [diff] [blame] | 443 | if (ret) |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 444 | video_put(vdev); |
| 445 | return ret; |
| 446 | } |
| 447 | |
| 448 | /* Override for the release function */ |
| 449 | static int v4l2_release(struct inode *inode, struct file *filp) |
| 450 | { |
| 451 | struct video_device *vdev = video_devdata(filp); |
Hans Verkuil | 65d9ff9 | 2009-03-29 20:19:38 -0300 | [diff] [blame] | 452 | int ret = 0; |
| 453 | |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 454 | if (vdev->fops->release) { |
| 455 | if (vdev->lock) |
| 456 | mutex_lock(vdev->lock); |
Hans Verkuil | 65d9ff9 | 2009-03-29 20:19:38 -0300 | [diff] [blame] | 457 | vdev->fops->release(filp); |
Hans Verkuil | ee6869a | 2010-09-26 08:47:38 -0300 | [diff] [blame] | 458 | if (vdev->lock) |
| 459 | mutex_unlock(vdev->lock); |
| 460 | } |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 461 | /* decrease the refcount unconditionally since the release() |
| 462 | return value is ignored. */ |
| 463 | video_put(vdev); |
| 464 | return ret; |
| 465 | } |
| 466 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 467 | static const struct file_operations v4l2_fops = { |
| 468 | .owner = THIS_MODULE, |
| 469 | .read = v4l2_read, |
| 470 | .write = v4l2_write, |
| 471 | .open = v4l2_open, |
Bob Liu | ecc6517 | 2011-05-06 05:20:09 -0300 | [diff] [blame] | 472 | .get_unmapped_area = v4l2_get_unmapped_area, |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 473 | .mmap = v4l2_mmap, |
Arnd Bergmann | 86a5ef7 | 2010-07-04 00:15:09 +0200 | [diff] [blame] | 474 | .unlocked_ioctl = v4l2_ioctl, |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 475 | #ifdef CONFIG_COMPAT |
Hans Verkuil | 9bb7cde | 2008-12-30 06:42:40 -0300 | [diff] [blame] | 476 | .compat_ioctl = v4l2_compat_ioctl32, |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 477 | #endif |
| 478 | .release = v4l2_release, |
| 479 | .poll = v4l2_poll, |
| 480 | .llseek = no_llseek, |
| 481 | }; |
| 482 | |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 483 | /** |
Hans Verkuil | 7ae0cd9 | 2009-06-19 11:32:56 -0300 | [diff] [blame] | 484 | * get_index - assign stream index number based on parent device |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 485 | * @vdev: video_device to assign index number to, vdev->parent should be assigned |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 486 | * |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 487 | * Note that when this is called the new device has not yet been registered |
Hans Verkuil | 7ae0cd9 | 2009-06-19 11:32:56 -0300 | [diff] [blame] | 488 | * in the video_device array, but it was able to obtain a minor number. |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 489 | * |
Hans Verkuil | 7ae0cd9 | 2009-06-19 11:32:56 -0300 | [diff] [blame] | 490 | * This means that we can always obtain a free stream index number since |
| 491 | * the worst case scenario is that there are VIDEO_NUM_DEVICES - 1 slots in |
| 492 | * use of the video_device array. |
| 493 | * |
| 494 | * Returns a free index number. |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 495 | */ |
Hans Verkuil | 7ae0cd9 | 2009-06-19 11:32:56 -0300 | [diff] [blame] | 496 | static int get_index(struct video_device *vdev) |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 497 | { |
Hans Verkuil | 775a05d | 2009-02-14 11:31:01 -0300 | [diff] [blame] | 498 | /* This can be static since this function is called with the global |
| 499 | videodev_lock held. */ |
| 500 | static DECLARE_BITMAP(used, VIDEO_NUM_DEVICES); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 501 | int i; |
| 502 | |
Hans Verkuil | 7ae0cd9 | 2009-06-19 11:32:56 -0300 | [diff] [blame] | 503 | /* Some drivers do not set the parent. In that case always return 0. */ |
Hans Verkuil | 806e5b7 | 2008-12-19 09:10:56 -0300 | [diff] [blame] | 504 | if (vdev->parent == NULL) |
Hans Verkuil | 7ae0cd9 | 2009-06-19 11:32:56 -0300 | [diff] [blame] | 505 | return 0; |
Hans Verkuil | 775a05d | 2009-02-14 11:31:01 -0300 | [diff] [blame] | 506 | |
| 507 | bitmap_zero(used, VIDEO_NUM_DEVICES); |
Hans Verkuil | 806e5b7 | 2008-12-19 09:10:56 -0300 | [diff] [blame] | 508 | |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 509 | for (i = 0; i < VIDEO_NUM_DEVICES; i++) { |
| 510 | if (video_device[i] != NULL && |
Hans Verkuil | 5e85e73 | 2008-07-20 06:31:39 -0300 | [diff] [blame] | 511 | video_device[i]->parent == vdev->parent) { |
Hans Verkuil | 775a05d | 2009-02-14 11:31:01 -0300 | [diff] [blame] | 512 | set_bit(video_device[i]->index, used); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 513 | } |
| 514 | } |
| 515 | |
Hans Verkuil | 7ae0cd9 | 2009-06-19 11:32:56 -0300 | [diff] [blame] | 516 | return find_first_zero_bit(used, VIDEO_NUM_DEVICES); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 517 | } |
| 518 | |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 519 | /** |
Laurent Pinchart | 2096a5d | 2009-12-09 08:38:49 -0300 | [diff] [blame] | 520 | * __video_register_device - register video4linux devices |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 521 | * @vdev: video device structure we want to register |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 522 | * @type: type of device to register |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 523 | * @nr: which device node number (0 == /dev/video0, 1 == /dev/video1, ... |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 524 | * -1 == first free) |
Hans Verkuil | 6b5270d | 2009-09-06 07:54:00 -0300 | [diff] [blame] | 525 | * @warn_if_nr_in_use: warn if the desired device node number |
| 526 | * was already in use and another number was chosen instead. |
Laurent Pinchart | 2096a5d | 2009-12-09 08:38:49 -0300 | [diff] [blame] | 527 | * @owner: module that owns the video device node |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 528 | * |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 529 | * The registration code assigns minor numbers and device node numbers |
| 530 | * based on the requested type and registers the new device node with |
| 531 | * the kernel. |
Hans Verkuil | 46b6337 | 2010-12-31 11:47:23 -0300 | [diff] [blame] | 532 | * |
| 533 | * This function assumes that struct video_device was zeroed when it |
| 534 | * was allocated and does not contain any stale date. |
| 535 | * |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 536 | * An error is returned if no free minor or device node number could be |
| 537 | * found, or if the registration of the device node failed. |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 538 | * |
| 539 | * Zero is returned on success. |
| 540 | * |
| 541 | * Valid types are |
| 542 | * |
| 543 | * %VFL_TYPE_GRABBER - A frame grabber |
| 544 | * |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 545 | * %VFL_TYPE_VBI - Vertical blank data (undecoded) |
| 546 | * |
| 547 | * %VFL_TYPE_RADIO - A radio card |
Laurent Pinchart | 2096a5d | 2009-12-09 08:38:49 -0300 | [diff] [blame] | 548 | * |
| 549 | * %VFL_TYPE_SUBDEV - A subdevice |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 550 | */ |
Laurent Pinchart | 2096a5d | 2009-12-09 08:38:49 -0300 | [diff] [blame] | 551 | int __video_register_device(struct video_device *vdev, int type, int nr, |
| 552 | int warn_if_nr_in_use, struct module *owner) |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 553 | { |
| 554 | int i = 0; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 555 | int ret; |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 556 | int minor_offset = 0; |
| 557 | int minor_cnt = VIDEO_NUM_DEVICES; |
| 558 | const char *name_base; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 559 | |
| 560 | /* A minor value of -1 marks this video device as never |
| 561 | having been registered */ |
Trent Piepho | 428c8d1 | 2009-03-03 18:51:52 -0300 | [diff] [blame] | 562 | vdev->minor = -1; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 563 | |
Hans Verkuil | d6e7497 | 2008-08-23 06:27:59 -0300 | [diff] [blame] | 564 | /* the release callback MUST be present */ |
Guennadi Liakhovetski | 1fc2b5f | 2011-12-06 05:33:03 -0300 | [diff] [blame] | 565 | if (WARN_ON(!vdev->release)) |
Henrik Kretzschmar | ee7aa9f | 2008-08-22 16:41:03 -0300 | [diff] [blame] | 566 | return -EINVAL; |
| 567 | |
Sakari Ailus | 1babcb4 | 2010-03-23 09:25:26 -0300 | [diff] [blame] | 568 | /* v4l2_fh support */ |
| 569 | spin_lock_init(&vdev->fh_lock); |
| 570 | INIT_LIST_HEAD(&vdev->fh_list); |
| 571 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 572 | /* Part 1: check device type */ |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 573 | switch (type) { |
| 574 | case VFL_TYPE_GRABBER: |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 575 | name_base = "video"; |
| 576 | break; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 577 | case VFL_TYPE_VBI: |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 578 | name_base = "vbi"; |
| 579 | break; |
| 580 | case VFL_TYPE_RADIO: |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 581 | name_base = "radio"; |
| 582 | break; |
Laurent Pinchart | 2096a5d | 2009-12-09 08:38:49 -0300 | [diff] [blame] | 583 | case VFL_TYPE_SUBDEV: |
| 584 | name_base = "v4l-subdev"; |
| 585 | break; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 586 | default: |
| 587 | printk(KERN_ERR "%s called with unknown type: %d\n", |
| 588 | __func__, type); |
Henrik Kretzschmar | 46f2c21 | 2008-09-03 16:47:39 -0300 | [diff] [blame] | 589 | return -EINVAL; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 590 | } |
| 591 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 592 | vdev->vfl_type = type; |
| 593 | vdev->cdev = NULL; |
Hans Verkuil | 11bbc1c | 2010-05-16 09:24:06 -0300 | [diff] [blame] | 594 | if (vdev->v4l2_dev) { |
| 595 | if (vdev->v4l2_dev->dev) |
| 596 | vdev->parent = vdev->v4l2_dev->dev; |
| 597 | if (vdev->ctrl_handler == NULL) |
| 598 | vdev->ctrl_handler = vdev->v4l2_dev->ctrl_handler; |
Hans Verkuil | b1a873a | 2011-03-22 10:14:07 -0300 | [diff] [blame] | 599 | /* If the prio state pointer is NULL, then use the v4l2_device |
| 600 | prio state. */ |
| 601 | if (vdev->prio == NULL) |
Hans Verkuil | 0f62fd6 | 2011-02-24 10:42:24 -0300 | [diff] [blame] | 602 | vdev->prio = &vdev->v4l2_dev->prio; |
Hans Verkuil | 11bbc1c | 2010-05-16 09:24:06 -0300 | [diff] [blame] | 603 | } |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 604 | |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 605 | /* Part 2: find a free minor, device node number and device index. */ |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 606 | #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES |
| 607 | /* Keep the ranges for the first four types for historical |
| 608 | * reasons. |
| 609 | * Newer devices (not yet in place) should use the range |
| 610 | * of 128-191 and just pick the first free minor there |
| 611 | * (new style). */ |
| 612 | switch (type) { |
| 613 | case VFL_TYPE_GRABBER: |
| 614 | minor_offset = 0; |
| 615 | minor_cnt = 64; |
| 616 | break; |
| 617 | case VFL_TYPE_RADIO: |
| 618 | minor_offset = 64; |
| 619 | minor_cnt = 64; |
| 620 | break; |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 621 | case VFL_TYPE_VBI: |
| 622 | minor_offset = 224; |
| 623 | minor_cnt = 32; |
| 624 | break; |
| 625 | default: |
| 626 | minor_offset = 128; |
| 627 | minor_cnt = 64; |
| 628 | break; |
| 629 | } |
| 630 | #endif |
| 631 | |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 632 | /* Pick a device node number */ |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 633 | mutex_lock(&videodev_lock); |
Hans Verkuil | 5062cb7 | 2009-09-07 03:40:24 -0300 | [diff] [blame] | 634 | nr = devnode_find(vdev, nr == -1 ? 0 : nr, minor_cnt); |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 635 | if (nr == minor_cnt) |
Hans Verkuil | 5062cb7 | 2009-09-07 03:40:24 -0300 | [diff] [blame] | 636 | nr = devnode_find(vdev, 0, minor_cnt); |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 637 | if (nr == minor_cnt) { |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 638 | printk(KERN_ERR "could not get a free device node number\n"); |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 639 | mutex_unlock(&videodev_lock); |
| 640 | return -ENFILE; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 641 | } |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 642 | #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 643 | /* 1-on-1 mapping of device node number to minor number */ |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 644 | i = nr; |
| 645 | #else |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 646 | /* The device node number and minor numbers are independent, so |
| 647 | we just find the first free minor number. */ |
Hans Verkuil | dd89601 | 2008-10-04 08:36:54 -0300 | [diff] [blame] | 648 | for (i = 0; i < VIDEO_NUM_DEVICES; i++) |
| 649 | if (video_device[i] == NULL) |
| 650 | break; |
| 651 | if (i == VIDEO_NUM_DEVICES) { |
| 652 | mutex_unlock(&videodev_lock); |
| 653 | printk(KERN_ERR "could not get a free minor\n"); |
| 654 | return -ENFILE; |
| 655 | } |
| 656 | #endif |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 657 | vdev->minor = i + minor_offset; |
| 658 | vdev->num = nr; |
Hans Verkuil | 5062cb7 | 2009-09-07 03:40:24 -0300 | [diff] [blame] | 659 | devnode_set(vdev); |
| 660 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 661 | /* Should not happen since we thought this minor was free */ |
| 662 | WARN_ON(video_device[vdev->minor] != NULL); |
Hans Verkuil | 7ae0cd9 | 2009-06-19 11:32:56 -0300 | [diff] [blame] | 663 | vdev->index = get_index(vdev); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 664 | mutex_unlock(&videodev_lock); |
| 665 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 666 | /* Part 3: Initialize the character device */ |
| 667 | vdev->cdev = cdev_alloc(); |
| 668 | if (vdev->cdev == NULL) { |
| 669 | ret = -ENOMEM; |
| 670 | goto cleanup; |
| 671 | } |
Arnd Bergmann | 86a5ef7 | 2010-07-04 00:15:09 +0200 | [diff] [blame] | 672 | vdev->cdev->ops = &v4l2_fops; |
Laurent Pinchart | 2096a5d | 2009-12-09 08:38:49 -0300 | [diff] [blame] | 673 | vdev->cdev->owner = owner; |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 674 | ret = cdev_add(vdev->cdev, MKDEV(VIDEO_MAJOR, vdev->minor), 1); |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 675 | if (ret < 0) { |
| 676 | printk(KERN_ERR "%s: cdev_add failed\n", __func__); |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 677 | kfree(vdev->cdev); |
| 678 | vdev->cdev = NULL; |
| 679 | goto cleanup; |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 680 | } |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 681 | |
| 682 | /* Part 4: register the device with sysfs */ |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 683 | vdev->dev.class = &video_class; |
| 684 | vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor); |
| 685 | if (vdev->parent) |
| 686 | vdev->dev.parent = vdev->parent; |
Hans Verkuil | 22e2212 | 2009-09-06 07:13:14 -0300 | [diff] [blame] | 687 | dev_set_name(&vdev->dev, "%s%d", name_base, vdev->num); |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 688 | ret = device_register(&vdev->dev); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 689 | if (ret < 0) { |
| 690 | printk(KERN_ERR "%s: device_register failed\n", __func__); |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 691 | goto cleanup; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 692 | } |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 693 | /* Register the release callback that will be called when the last |
| 694 | reference to the device goes away. */ |
| 695 | vdev->dev.release = v4l2_device_release; |
| 696 | |
Hans Verkuil | 6b5270d | 2009-09-06 07:54:00 -0300 | [diff] [blame] | 697 | if (nr != -1 && nr != vdev->num && warn_if_nr_in_use) |
Laurent Pinchart | eac8ea5 | 2009-11-27 13:56:50 -0300 | [diff] [blame] | 698 | printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__, |
| 699 | name_base, nr, video_device_node_name(vdev)); |
Hans Verkuil | bedf8bc | 2011-03-12 06:37:19 -0300 | [diff] [blame] | 700 | |
| 701 | /* Increase v4l2_device refcount */ |
| 702 | if (vdev->v4l2_dev) |
| 703 | v4l2_device_get(vdev->v4l2_dev); |
| 704 | |
Laurent Pinchart | 2c0ab67 | 2009-12-09 08:40:10 -0300 | [diff] [blame] | 705 | #if defined(CONFIG_MEDIA_CONTROLLER) |
| 706 | /* Part 5: Register the entity. */ |
Laurent Pinchart | c4f0b78 | 2011-04-08 09:04:06 -0300 | [diff] [blame] | 707 | if (vdev->v4l2_dev && vdev->v4l2_dev->mdev && |
| 708 | vdev->vfl_type != VFL_TYPE_SUBDEV) { |
Laurent Pinchart | 2c0ab67 | 2009-12-09 08:40:10 -0300 | [diff] [blame] | 709 | vdev->entity.type = MEDIA_ENT_T_DEVNODE_V4L; |
| 710 | vdev->entity.name = vdev->name; |
Clemens Ladisch | fa5034c | 2011-11-05 18:42:01 -0300 | [diff] [blame] | 711 | vdev->entity.info.v4l.major = VIDEO_MAJOR; |
| 712 | vdev->entity.info.v4l.minor = vdev->minor; |
Laurent Pinchart | 2c0ab67 | 2009-12-09 08:40:10 -0300 | [diff] [blame] | 713 | ret = media_device_register_entity(vdev->v4l2_dev->mdev, |
| 714 | &vdev->entity); |
| 715 | if (ret < 0) |
| 716 | printk(KERN_WARNING |
| 717 | "%s: media_device_register_entity failed\n", |
| 718 | __func__); |
| 719 | } |
| 720 | #endif |
| 721 | /* Part 6: Activate this minor. The char device can now be used. */ |
Laurent Pinchart | 957b4aa | 2009-11-27 13:57:22 -0300 | [diff] [blame] | 722 | set_bit(V4L2_FL_REGISTERED, &vdev->flags); |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 723 | mutex_lock(&videodev_lock); |
| 724 | video_device[vdev->minor] = vdev; |
| 725 | mutex_unlock(&videodev_lock); |
Laurent Pinchart | 2c0ab67 | 2009-12-09 08:40:10 -0300 | [diff] [blame] | 726 | |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 727 | return 0; |
| 728 | |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 729 | cleanup: |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 730 | mutex_lock(&videodev_lock); |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 731 | if (vdev->cdev) |
| 732 | cdev_del(vdev->cdev); |
Hans Verkuil | 5062cb7 | 2009-09-07 03:40:24 -0300 | [diff] [blame] | 733 | devnode_clear(vdev); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 734 | mutex_unlock(&videodev_lock); |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 735 | /* Mark this video device as never having been registered. */ |
| 736 | vdev->minor = -1; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 737 | return ret; |
| 738 | } |
Laurent Pinchart | 2096a5d | 2009-12-09 08:38:49 -0300 | [diff] [blame] | 739 | EXPORT_SYMBOL(__video_register_device); |
Hans Verkuil | 6b5270d | 2009-09-06 07:54:00 -0300 | [diff] [blame] | 740 | |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 741 | /** |
| 742 | * video_unregister_device - unregister a video4linux device |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 743 | * @vdev: the device to unregister |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 744 | * |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 745 | * This unregisters the passed device. Future open calls will |
| 746 | * be met with errors. |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 747 | */ |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 748 | void video_unregister_device(struct video_device *vdev) |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 749 | { |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 750 | /* Check if vdev was ever registered at all */ |
Laurent Pinchart | 957b4aa | 2009-11-27 13:57:22 -0300 | [diff] [blame] | 751 | if (!vdev || !video_is_registered(vdev)) |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 752 | return; |
| 753 | |
Hans Verkuil | ca9afe6 | 2010-11-26 06:54:53 -0300 | [diff] [blame] | 754 | mutex_lock(&videodev_lock); |
| 755 | /* This must be in a critical section to prevent a race with v4l2_open. |
| 756 | * Once this bit has been cleared video_get may never be called again. |
| 757 | */ |
Laurent Pinchart | 957b4aa | 2009-11-27 13:57:22 -0300 | [diff] [blame] | 758 | clear_bit(V4L2_FL_REGISTERED, &vdev->flags); |
Hans Verkuil | ca9afe6 | 2010-11-26 06:54:53 -0300 | [diff] [blame] | 759 | mutex_unlock(&videodev_lock); |
Hans Verkuil | dc93a70 | 2008-12-19 21:28:27 -0300 | [diff] [blame] | 760 | device_unregister(&vdev->dev); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 761 | } |
| 762 | EXPORT_SYMBOL(video_unregister_device); |
| 763 | |
| 764 | /* |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 765 | * Initialise video for linux |
| 766 | */ |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 767 | static int __init videodev_init(void) |
| 768 | { |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 769 | dev_t dev = MKDEV(VIDEO_MAJOR, 0); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 770 | int ret; |
| 771 | |
| 772 | printk(KERN_INFO "Linux video capture interface: v2.00\n"); |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 773 | ret = register_chrdev_region(dev, VIDEO_NUM_DEVICES, VIDEO_NAME); |
| 774 | if (ret < 0) { |
| 775 | printk(KERN_WARNING "videodev: unable to get major %d\n", |
| 776 | VIDEO_MAJOR); |
| 777 | return ret; |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 778 | } |
| 779 | |
| 780 | ret = class_register(&video_class); |
| 781 | if (ret < 0) { |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 782 | unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 783 | printk(KERN_WARNING "video_dev: class_register failed\n"); |
| 784 | return -EIO; |
| 785 | } |
| 786 | |
| 787 | return 0; |
| 788 | } |
| 789 | |
| 790 | static void __exit videodev_exit(void) |
| 791 | { |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 792 | dev_t dev = MKDEV(VIDEO_MAJOR, 0); |
| 793 | |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 794 | class_unregister(&video_class); |
Hans Verkuil | 7f8ecfa | 2008-08-29 17:31:35 -0300 | [diff] [blame] | 795 | unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 796 | } |
| 797 | |
Bhupesh Sharma | ee981c6 | 2012-03-12 05:09:02 -0300 | [diff] [blame] | 798 | subsys_initcall(videodev_init); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 799 | module_exit(videodev_exit) |
| 800 | |
| 801 | MODULE_AUTHOR("Alan Cox, Mauro Carvalho Chehab <mchehab@infradead.org>"); |
| 802 | MODULE_DESCRIPTION("Device registrar for Video4Linux drivers v2"); |
| 803 | MODULE_LICENSE("GPL"); |
Scott James Remnant | cbb72b0 | 2009-03-02 15:40:57 -0300 | [diff] [blame] | 804 | MODULE_ALIAS_CHARDEV_MAJOR(VIDEO_MAJOR); |
Hans Verkuil | 27a5e6d | 2008-07-20 08:43:17 -0300 | [diff] [blame] | 805 | |
| 806 | |
| 807 | /* |
| 808 | * Local variables: |
| 809 | * c-basic-offset: 8 |
| 810 | * End: |
| 811 | */ |