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Commit | Line | Data |
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27a5e6d3 HV |
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 | * | |
d9b01449 | 12 | * Authors: Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1) |
27a5e6d3 HV |
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> | |
86a5ef7d | 28 | #include <linux/smp_lock.h> |
27a5e6d3 HV |
29 | #include <asm/uaccess.h> |
30 | #include <asm/system.h> | |
31 | ||
32 | #include <media/v4l2-common.h> | |
9bea3514 | 33 | #include <media/v4l2-device.h> |
bec43661 | 34 | #include <media/v4l2-ioctl.h> |
27a5e6d3 HV |
35 | |
36 | #define VIDEO_NUM_DEVICES 256 | |
37 | #define VIDEO_NAME "video4linux" | |
38 | ||
39 | /* | |
40 | * sysfs stuff | |
41 | */ | |
42 | ||
43 | static ssize_t show_index(struct device *cd, | |
44 | struct device_attribute *attr, char *buf) | |
45 | { | |
dc93a70c | 46 | struct video_device *vdev = to_video_device(cd); |
bfa8a273 | 47 | |
dc93a70c | 48 | return sprintf(buf, "%i\n", vdev->index); |
27a5e6d3 HV |
49 | } |
50 | ||
51 | static ssize_t show_name(struct device *cd, | |
52 | struct device_attribute *attr, char *buf) | |
53 | { | |
dc93a70c | 54 | struct video_device *vdev = to_video_device(cd); |
bfa8a273 | 55 | |
dc93a70c | 56 | return sprintf(buf, "%.*s\n", (int)sizeof(vdev->name), vdev->name); |
27a5e6d3 HV |
57 | } |
58 | ||
59 | static struct device_attribute video_device_attrs[] = { | |
60 | __ATTR(name, S_IRUGO, show_name, NULL), | |
61 | __ATTR(index, S_IRUGO, show_index, NULL), | |
62 | __ATTR_NULL | |
63 | }; | |
64 | ||
7f8ecfab HV |
65 | /* |
66 | * Active devices | |
67 | */ | |
68 | static struct video_device *video_device[VIDEO_NUM_DEVICES]; | |
69 | static DEFINE_MUTEX(videodev_lock); | |
22e22125 | 70 | static DECLARE_BITMAP(devnode_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES); |
7f8ecfab | 71 | |
5062cb70 HV |
72 | /* Device node utility functions */ |
73 | ||
74 | /* Note: these utility functions all assume that vfl_type is in the range | |
75 | [0, VFL_TYPE_MAX-1]. */ | |
76 | ||
77 | #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES | |
78 | /* Return the bitmap corresponding to vfl_type. */ | |
79 | static inline unsigned long *devnode_bits(int vfl_type) | |
80 | { | |
81 | /* Any types not assigned to fixed minor ranges must be mapped to | |
82 | one single bitmap for the purposes of finding a free node number | |
83 | since all those unassigned types use the same minor range. */ | |
226c0eea | 84 | int idx = (vfl_type > VFL_TYPE_RADIO) ? VFL_TYPE_MAX - 1 : vfl_type; |
5062cb70 HV |
85 | |
86 | return devnode_nums[idx]; | |
87 | } | |
88 | #else | |
89 | /* Return the bitmap corresponding to vfl_type. */ | |
90 | static inline unsigned long *devnode_bits(int vfl_type) | |
91 | { | |
92 | return devnode_nums[vfl_type]; | |
93 | } | |
94 | #endif | |
95 | ||
96 | /* Mark device node number vdev->num as used */ | |
97 | static inline void devnode_set(struct video_device *vdev) | |
98 | { | |
99 | set_bit(vdev->num, devnode_bits(vdev->vfl_type)); | |
100 | } | |
101 | ||
102 | /* Mark device node number vdev->num as unused */ | |
103 | static inline void devnode_clear(struct video_device *vdev) | |
104 | { | |
105 | clear_bit(vdev->num, devnode_bits(vdev->vfl_type)); | |
106 | } | |
107 | ||
108 | /* Try to find a free device node number in the range [from, to> */ | |
109 | static inline int devnode_find(struct video_device *vdev, int from, int to) | |
110 | { | |
111 | return find_next_zero_bit(devnode_bits(vdev->vfl_type), to, from); | |
112 | } | |
113 | ||
27a5e6d3 HV |
114 | struct video_device *video_device_alloc(void) |
115 | { | |
bfa8a273 | 116 | return kzalloc(sizeof(struct video_device), GFP_KERNEL); |
27a5e6d3 HV |
117 | } |
118 | EXPORT_SYMBOL(video_device_alloc); | |
119 | ||
dc93a70c | 120 | void video_device_release(struct video_device *vdev) |
27a5e6d3 | 121 | { |
dc93a70c | 122 | kfree(vdev); |
27a5e6d3 HV |
123 | } |
124 | EXPORT_SYMBOL(video_device_release); | |
125 | ||
dc93a70c | 126 | void video_device_release_empty(struct video_device *vdev) |
f9e86b5e HV |
127 | { |
128 | /* Do nothing */ | |
129 | /* Only valid when the video_device struct is a static. */ | |
130 | } | |
131 | EXPORT_SYMBOL(video_device_release_empty); | |
132 | ||
dc93a70c | 133 | static inline void video_get(struct video_device *vdev) |
7f8ecfab | 134 | { |
dc93a70c HV |
135 | get_device(&vdev->dev); |
136 | } | |
137 | ||
138 | static inline void video_put(struct video_device *vdev) | |
139 | { | |
140 | put_device(&vdev->dev); | |
141 | } | |
142 | ||
143 | /* Called when the last user of the video device exits. */ | |
144 | static void v4l2_device_release(struct device *cd) | |
145 | { | |
146 | struct video_device *vdev = to_video_device(cd); | |
7f8ecfab HV |
147 | |
148 | mutex_lock(&videodev_lock); | |
dc93a70c | 149 | if (video_device[vdev->minor] != vdev) { |
6ea9a182 | 150 | mutex_unlock(&videodev_lock); |
dc93a70c HV |
151 | /* should not happen */ |
152 | WARN_ON(1); | |
6ea9a182 HV |
153 | return; |
154 | } | |
7f8ecfab HV |
155 | |
156 | /* Free up this device for reuse */ | |
dc93a70c | 157 | video_device[vdev->minor] = NULL; |
7f8ecfab | 158 | |
dc93a70c HV |
159 | /* Delete the cdev on this minor as well */ |
160 | cdev_del(vdev->cdev); | |
161 | /* Just in case some driver tries to access this from | |
162 | the release() callback. */ | |
163 | vdev->cdev = NULL; | |
7f8ecfab | 164 | |
22e22125 | 165 | /* Mark device node number as free */ |
5062cb70 | 166 | devnode_clear(vdev); |
7f8ecfab | 167 | |
dc93a70c | 168 | mutex_unlock(&videodev_lock); |
27a5e6d3 | 169 | |
dc93a70c HV |
170 | /* Release video_device and perform other |
171 | cleanups as needed. */ | |
172 | vdev->release(vdev); | |
27a5e6d3 HV |
173 | } |
174 | ||
175 | static struct class video_class = { | |
176 | .name = VIDEO_NAME, | |
177 | .dev_attrs = video_device_attrs, | |
27a5e6d3 HV |
178 | }; |
179 | ||
27a5e6d3 HV |
180 | struct video_device *video_devdata(struct file *file) |
181 | { | |
182 | return video_device[iminor(file->f_path.dentry->d_inode)]; | |
183 | } | |
184 | EXPORT_SYMBOL(video_devdata); | |
185 | ||
dc93a70c HV |
186 | static ssize_t v4l2_read(struct file *filp, char __user *buf, |
187 | size_t sz, loff_t *off) | |
188 | { | |
189 | struct video_device *vdev = video_devdata(filp); | |
ee6869af | 190 | int ret = -EIO; |
dc93a70c HV |
191 | |
192 | if (!vdev->fops->read) | |
193 | return -EINVAL; | |
ee6869af HV |
194 | if (vdev->lock) |
195 | mutex_lock(vdev->lock); | |
196 | if (video_is_registered(vdev)) | |
197 | ret = vdev->fops->read(filp, buf, sz, off); | |
198 | if (vdev->lock) | |
199 | mutex_unlock(vdev->lock); | |
200 | return ret; | |
dc93a70c HV |
201 | } |
202 | ||
203 | static ssize_t v4l2_write(struct file *filp, const char __user *buf, | |
204 | size_t sz, loff_t *off) | |
205 | { | |
206 | struct video_device *vdev = video_devdata(filp); | |
ee6869af | 207 | int ret = -EIO; |
dc93a70c HV |
208 | |
209 | if (!vdev->fops->write) | |
210 | return -EINVAL; | |
ee6869af HV |
211 | if (vdev->lock) |
212 | mutex_lock(vdev->lock); | |
213 | if (video_is_registered(vdev)) | |
214 | ret = vdev->fops->write(filp, buf, sz, off); | |
215 | if (vdev->lock) | |
216 | mutex_unlock(vdev->lock); | |
217 | return ret; | |
dc93a70c HV |
218 | } |
219 | ||
220 | static unsigned int v4l2_poll(struct file *filp, struct poll_table_struct *poll) | |
221 | { | |
222 | struct video_device *vdev = video_devdata(filp); | |
ee6869af HV |
223 | int ret = DEFAULT_POLLMASK; |
224 | ||
225 | if (!vdev->fops->poll) | |
226 | return ret; | |
227 | if (vdev->lock) | |
228 | mutex_lock(vdev->lock); | |
229 | if (video_is_registered(vdev)) | |
230 | ret = vdev->fops->poll(filp, poll); | |
231 | if (vdev->lock) | |
232 | mutex_unlock(vdev->lock); | |
233 | return ret; | |
dc93a70c HV |
234 | } |
235 | ||
86a5ef7d | 236 | static long v4l2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) |
dc93a70c HV |
237 | { |
238 | struct video_device *vdev = video_devdata(filp); | |
72420630 | 239 | int ret = -ENODEV; |
dc93a70c | 240 | |
86a5ef7d | 241 | if (vdev->fops->unlocked_ioctl) { |
ee6869af HV |
242 | if (vdev->lock) |
243 | mutex_lock(vdev->lock); | |
72420630 MCC |
244 | if (video_is_registered(vdev)) |
245 | ret = vdev->fops->unlocked_ioctl(filp, cmd, arg); | |
ee6869af HV |
246 | if (vdev->lock) |
247 | mutex_unlock(vdev->lock); | |
86a5ef7d AB |
248 | } else if (vdev->fops->ioctl) { |
249 | /* TODO: convert all drivers to unlocked_ioctl */ | |
250 | lock_kernel(); | |
72420630 MCC |
251 | if (video_is_registered(vdev)) |
252 | ret = vdev->fops->ioctl(filp, cmd, arg); | |
86a5ef7d AB |
253 | unlock_kernel(); |
254 | } else | |
255 | ret = -ENOTTY; | |
dc93a70c | 256 | |
86a5ef7d | 257 | return ret; |
dc93a70c HV |
258 | } |
259 | ||
dc93a70c HV |
260 | static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm) |
261 | { | |
262 | struct video_device *vdev = video_devdata(filp); | |
ee6869af HV |
263 | int ret = -ENODEV; |
264 | ||
265 | if (!vdev->fops->mmap) | |
266 | return ret; | |
267 | if (vdev->lock) | |
268 | mutex_lock(vdev->lock); | |
269 | if (video_is_registered(vdev)) | |
270 | ret = vdev->fops->mmap(filp, vm); | |
271 | if (vdev->lock) | |
272 | mutex_unlock(vdev->lock); | |
273 | return ret; | |
dc93a70c HV |
274 | } |
275 | ||
276 | /* Override for the open function */ | |
277 | static int v4l2_open(struct inode *inode, struct file *filp) | |
278 | { | |
279 | struct video_device *vdev; | |
65d9ff9c | 280 | int ret = 0; |
dc93a70c HV |
281 | |
282 | /* Check if the video device is available */ | |
283 | mutex_lock(&videodev_lock); | |
284 | vdev = video_devdata(filp); | |
ee6869af HV |
285 | /* return ENODEV if the video device has already been removed. */ |
286 | if (vdev == NULL) { | |
dc93a70c HV |
287 | mutex_unlock(&videodev_lock); |
288 | return -ENODEV; | |
289 | } | |
290 | /* and increase the device refcount */ | |
291 | video_get(vdev); | |
292 | mutex_unlock(&videodev_lock); | |
ee6869af HV |
293 | if (vdev->fops->open) { |
294 | if (vdev->lock) | |
295 | mutex_lock(vdev->lock); | |
296 | if (video_is_registered(vdev)) | |
297 | ret = vdev->fops->open(filp); | |
298 | else | |
299 | ret = -ENODEV; | |
300 | if (vdev->lock) | |
301 | mutex_unlock(vdev->lock); | |
302 | } | |
65d9ff9c | 303 | |
dc93a70c HV |
304 | /* decrease the refcount in case of an error */ |
305 | if (ret) | |
306 | video_put(vdev); | |
307 | return ret; | |
308 | } | |
309 | ||
310 | /* Override for the release function */ | |
311 | static int v4l2_release(struct inode *inode, struct file *filp) | |
312 | { | |
313 | struct video_device *vdev = video_devdata(filp); | |
65d9ff9c HV |
314 | int ret = 0; |
315 | ||
ee6869af HV |
316 | if (vdev->fops->release) { |
317 | if (vdev->lock) | |
318 | mutex_lock(vdev->lock); | |
65d9ff9c | 319 | vdev->fops->release(filp); |
ee6869af HV |
320 | if (vdev->lock) |
321 | mutex_unlock(vdev->lock); | |
322 | } | |
dc93a70c HV |
323 | |
324 | /* decrease the refcount unconditionally since the release() | |
325 | return value is ignored. */ | |
326 | video_put(vdev); | |
327 | return ret; | |
328 | } | |
329 | ||
dc93a70c HV |
330 | static const struct file_operations v4l2_fops = { |
331 | .owner = THIS_MODULE, | |
332 | .read = v4l2_read, | |
333 | .write = v4l2_write, | |
334 | .open = v4l2_open, | |
335 | .mmap = v4l2_mmap, | |
86a5ef7d | 336 | .unlocked_ioctl = v4l2_ioctl, |
dc93a70c | 337 | #ifdef CONFIG_COMPAT |
9bb7cde7 | 338 | .compat_ioctl = v4l2_compat_ioctl32, |
dc93a70c HV |
339 | #endif |
340 | .release = v4l2_release, | |
341 | .poll = v4l2_poll, | |
342 | .llseek = no_llseek, | |
343 | }; | |
344 | ||
27a5e6d3 | 345 | /** |
7ae0cd9b | 346 | * get_index - assign stream index number based on parent device |
dc93a70c | 347 | * @vdev: video_device to assign index number to, vdev->parent should be assigned |
27a5e6d3 | 348 | * |
dc93a70c | 349 | * Note that when this is called the new device has not yet been registered |
7ae0cd9b | 350 | * in the video_device array, but it was able to obtain a minor number. |
27a5e6d3 | 351 | * |
7ae0cd9b HV |
352 | * This means that we can always obtain a free stream index number since |
353 | * the worst case scenario is that there are VIDEO_NUM_DEVICES - 1 slots in | |
354 | * use of the video_device array. | |
355 | * | |
356 | * Returns a free index number. | |
27a5e6d3 | 357 | */ |
7ae0cd9b | 358 | static int get_index(struct video_device *vdev) |
27a5e6d3 | 359 | { |
775a05dd HV |
360 | /* This can be static since this function is called with the global |
361 | videodev_lock held. */ | |
362 | static DECLARE_BITMAP(used, VIDEO_NUM_DEVICES); | |
27a5e6d3 HV |
363 | int i; |
364 | ||
7ae0cd9b | 365 | /* Some drivers do not set the parent. In that case always return 0. */ |
806e5b7c | 366 | if (vdev->parent == NULL) |
7ae0cd9b | 367 | return 0; |
775a05dd HV |
368 | |
369 | bitmap_zero(used, VIDEO_NUM_DEVICES); | |
806e5b7c | 370 | |
27a5e6d3 HV |
371 | for (i = 0; i < VIDEO_NUM_DEVICES; i++) { |
372 | if (video_device[i] != NULL && | |
5e85e732 | 373 | video_device[i]->parent == vdev->parent) { |
775a05dd | 374 | set_bit(video_device[i]->index, used); |
27a5e6d3 HV |
375 | } |
376 | } | |
377 | ||
7ae0cd9b | 378 | return find_first_zero_bit(used, VIDEO_NUM_DEVICES); |
27a5e6d3 HV |
379 | } |
380 | ||
27a5e6d3 | 381 | /** |
7ae0cd9b | 382 | * video_register_device - register video4linux devices |
dc93a70c | 383 | * @vdev: video device structure we want to register |
27a5e6d3 | 384 | * @type: type of device to register |
22e22125 | 385 | * @nr: which device node number (0 == /dev/video0, 1 == /dev/video1, ... |
27a5e6d3 | 386 | * -1 == first free) |
6b5270d2 HV |
387 | * @warn_if_nr_in_use: warn if the desired device node number |
388 | * was already in use and another number was chosen instead. | |
27a5e6d3 | 389 | * |
22e22125 HV |
390 | * The registration code assigns minor numbers and device node numbers |
391 | * based on the requested type and registers the new device node with | |
392 | * the kernel. | |
393 | * An error is returned if no free minor or device node number could be | |
394 | * found, or if the registration of the device node failed. | |
27a5e6d3 HV |
395 | * |
396 | * Zero is returned on success. | |
397 | * | |
398 | * Valid types are | |
399 | * | |
400 | * %VFL_TYPE_GRABBER - A frame grabber | |
401 | * | |
27a5e6d3 HV |
402 | * %VFL_TYPE_VBI - Vertical blank data (undecoded) |
403 | * | |
404 | * %VFL_TYPE_RADIO - A radio card | |
405 | */ | |
6b5270d2 HV |
406 | static int __video_register_device(struct video_device *vdev, int type, int nr, |
407 | int warn_if_nr_in_use) | |
27a5e6d3 HV |
408 | { |
409 | int i = 0; | |
27a5e6d3 | 410 | int ret; |
dd89601d HV |
411 | int minor_offset = 0; |
412 | int minor_cnt = VIDEO_NUM_DEVICES; | |
413 | const char *name_base; | |
1bb64194 | 414 | void *priv = vdev->dev.p; |
27a5e6d3 | 415 | |
dc93a70c HV |
416 | /* A minor value of -1 marks this video device as never |
417 | having been registered */ | |
428c8d19 | 418 | vdev->minor = -1; |
ee7aa9f8 | 419 | |
dc93a70c | 420 | /* the release callback MUST be present */ |
428c8d19 TP |
421 | WARN_ON(!vdev->release); |
422 | if (!vdev->release) | |
f3b9f50e HK |
423 | return -EINVAL; |
424 | ||
1babcb46 SA |
425 | /* v4l2_fh support */ |
426 | spin_lock_init(&vdev->fh_lock); | |
427 | INIT_LIST_HEAD(&vdev->fh_list); | |
428 | ||
dc93a70c | 429 | /* Part 1: check device type */ |
27a5e6d3 HV |
430 | switch (type) { |
431 | case VFL_TYPE_GRABBER: | |
27a5e6d3 HV |
432 | name_base = "video"; |
433 | break; | |
27a5e6d3 | 434 | case VFL_TYPE_VBI: |
27a5e6d3 HV |
435 | name_base = "vbi"; |
436 | break; | |
437 | case VFL_TYPE_RADIO: | |
27a5e6d3 HV |
438 | name_base = "radio"; |
439 | break; | |
440 | default: | |
441 | printk(KERN_ERR "%s called with unknown type: %d\n", | |
442 | __func__, type); | |
46f2c21c | 443 | return -EINVAL; |
27a5e6d3 HV |
444 | } |
445 | ||
dc93a70c HV |
446 | vdev->vfl_type = type; |
447 | vdev->cdev = NULL; | |
11bbc1ca HV |
448 | if (vdev->v4l2_dev) { |
449 | if (vdev->v4l2_dev->dev) | |
450 | vdev->parent = vdev->v4l2_dev->dev; | |
451 | if (vdev->ctrl_handler == NULL) | |
452 | vdev->ctrl_handler = vdev->v4l2_dev->ctrl_handler; | |
453 | } | |
dd89601d | 454 | |
22e22125 | 455 | /* Part 2: find a free minor, device node number and device index. */ |
dd89601d HV |
456 | #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES |
457 | /* Keep the ranges for the first four types for historical | |
458 | * reasons. | |
459 | * Newer devices (not yet in place) should use the range | |
460 | * of 128-191 and just pick the first free minor there | |
461 | * (new style). */ | |
462 | switch (type) { | |
463 | case VFL_TYPE_GRABBER: | |
464 | minor_offset = 0; | |
465 | minor_cnt = 64; | |
466 | break; | |
467 | case VFL_TYPE_RADIO: | |
468 | minor_offset = 64; | |
469 | minor_cnt = 64; | |
470 | break; | |
dd89601d HV |
471 | case VFL_TYPE_VBI: |
472 | minor_offset = 224; | |
473 | minor_cnt = 32; | |
474 | break; | |
475 | default: | |
476 | minor_offset = 128; | |
477 | minor_cnt = 64; | |
478 | break; | |
479 | } | |
480 | #endif | |
481 | ||
22e22125 | 482 | /* Pick a device node number */ |
27a5e6d3 | 483 | mutex_lock(&videodev_lock); |
5062cb70 | 484 | nr = devnode_find(vdev, nr == -1 ? 0 : nr, minor_cnt); |
dd89601d | 485 | if (nr == minor_cnt) |
5062cb70 | 486 | nr = devnode_find(vdev, 0, minor_cnt); |
dd89601d | 487 | if (nr == minor_cnt) { |
22e22125 | 488 | printk(KERN_ERR "could not get a free device node number\n"); |
dd89601d HV |
489 | mutex_unlock(&videodev_lock); |
490 | return -ENFILE; | |
27a5e6d3 | 491 | } |
dd89601d | 492 | #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES |
22e22125 | 493 | /* 1-on-1 mapping of device node number to minor number */ |
dd89601d HV |
494 | i = nr; |
495 | #else | |
22e22125 HV |
496 | /* The device node number and minor numbers are independent, so |
497 | we just find the first free minor number. */ | |
dd89601d HV |
498 | for (i = 0; i < VIDEO_NUM_DEVICES; i++) |
499 | if (video_device[i] == NULL) | |
500 | break; | |
501 | if (i == VIDEO_NUM_DEVICES) { | |
502 | mutex_unlock(&videodev_lock); | |
503 | printk(KERN_ERR "could not get a free minor\n"); | |
504 | return -ENFILE; | |
505 | } | |
506 | #endif | |
dc93a70c HV |
507 | vdev->minor = i + minor_offset; |
508 | vdev->num = nr; | |
5062cb70 HV |
509 | devnode_set(vdev); |
510 | ||
dc93a70c HV |
511 | /* Should not happen since we thought this minor was free */ |
512 | WARN_ON(video_device[vdev->minor] != NULL); | |
7ae0cd9b | 513 | vdev->index = get_index(vdev); |
27a5e6d3 HV |
514 | mutex_unlock(&videodev_lock); |
515 | ||
dc93a70c HV |
516 | /* Part 3: Initialize the character device */ |
517 | vdev->cdev = cdev_alloc(); | |
518 | if (vdev->cdev == NULL) { | |
519 | ret = -ENOMEM; | |
520 | goto cleanup; | |
521 | } | |
86a5ef7d | 522 | vdev->cdev->ops = &v4l2_fops; |
dc93a70c HV |
523 | vdev->cdev->owner = vdev->fops->owner; |
524 | ret = cdev_add(vdev->cdev, MKDEV(VIDEO_MAJOR, vdev->minor), 1); | |
7f8ecfab HV |
525 | if (ret < 0) { |
526 | printk(KERN_ERR "%s: cdev_add failed\n", __func__); | |
dc93a70c HV |
527 | kfree(vdev->cdev); |
528 | vdev->cdev = NULL; | |
529 | goto cleanup; | |
7f8ecfab | 530 | } |
dc93a70c HV |
531 | |
532 | /* Part 4: register the device with sysfs */ | |
533 | memset(&vdev->dev, 0, sizeof(vdev->dev)); | |
1bb64194 | 534 | /* The memset above cleared the device's device_private, so |
9d95af9d | 535 | put back the copy we made earlier. */ |
1bb64194 | 536 | vdev->dev.p = priv; |
dc93a70c HV |
537 | vdev->dev.class = &video_class; |
538 | vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor); | |
539 | if (vdev->parent) | |
540 | vdev->dev.parent = vdev->parent; | |
22e22125 | 541 | dev_set_name(&vdev->dev, "%s%d", name_base, vdev->num); |
dc93a70c | 542 | ret = device_register(&vdev->dev); |
27a5e6d3 HV |
543 | if (ret < 0) { |
544 | printk(KERN_ERR "%s: device_register failed\n", __func__); | |
dc93a70c | 545 | goto cleanup; |
27a5e6d3 | 546 | } |
dc93a70c HV |
547 | /* Register the release callback that will be called when the last |
548 | reference to the device goes away. */ | |
549 | vdev->dev.release = v4l2_device_release; | |
27a5e6d3 | 550 | |
6b5270d2 | 551 | if (nr != -1 && nr != vdev->num && warn_if_nr_in_use) |
eac8ea53 LP |
552 | printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__, |
553 | name_base, nr, video_device_node_name(vdev)); | |
6b5270d2 | 554 | |
dc93a70c | 555 | /* Part 5: Activate this minor. The char device can now be used. */ |
957b4aa9 | 556 | set_bit(V4L2_FL_REGISTERED, &vdev->flags); |
dc93a70c HV |
557 | mutex_lock(&videodev_lock); |
558 | video_device[vdev->minor] = vdev; | |
559 | mutex_unlock(&videodev_lock); | |
560 | return 0; | |
7f8ecfab | 561 | |
dc93a70c | 562 | cleanup: |
27a5e6d3 | 563 | mutex_lock(&videodev_lock); |
dc93a70c HV |
564 | if (vdev->cdev) |
565 | cdev_del(vdev->cdev); | |
5062cb70 | 566 | devnode_clear(vdev); |
27a5e6d3 | 567 | mutex_unlock(&videodev_lock); |
dc93a70c HV |
568 | /* Mark this video device as never having been registered. */ |
569 | vdev->minor = -1; | |
27a5e6d3 HV |
570 | return ret; |
571 | } | |
6b5270d2 HV |
572 | |
573 | int video_register_device(struct video_device *vdev, int type, int nr) | |
574 | { | |
575 | return __video_register_device(vdev, type, nr, 1); | |
576 | } | |
7ae0cd9b | 577 | EXPORT_SYMBOL(video_register_device); |
27a5e6d3 | 578 | |
6b5270d2 HV |
579 | int video_register_device_no_warn(struct video_device *vdev, int type, int nr) |
580 | { | |
581 | return __video_register_device(vdev, type, nr, 0); | |
582 | } | |
583 | EXPORT_SYMBOL(video_register_device_no_warn); | |
584 | ||
27a5e6d3 HV |
585 | /** |
586 | * video_unregister_device - unregister a video4linux device | |
dc93a70c | 587 | * @vdev: the device to unregister |
27a5e6d3 | 588 | * |
dc93a70c HV |
589 | * This unregisters the passed device. Future open calls will |
590 | * be met with errors. | |
27a5e6d3 | 591 | */ |
dc93a70c | 592 | void video_unregister_device(struct video_device *vdev) |
27a5e6d3 | 593 | { |
dc93a70c | 594 | /* Check if vdev was ever registered at all */ |
957b4aa9 | 595 | if (!vdev || !video_is_registered(vdev)) |
dc93a70c HV |
596 | return; |
597 | ||
957b4aa9 | 598 | clear_bit(V4L2_FL_REGISTERED, &vdev->flags); |
dc93a70c | 599 | device_unregister(&vdev->dev); |
27a5e6d3 HV |
600 | } |
601 | EXPORT_SYMBOL(video_unregister_device); | |
602 | ||
27a5e6d3 HV |
603 | /* |
604 | * Initialise video for linux | |
605 | */ | |
27a5e6d3 HV |
606 | static int __init videodev_init(void) |
607 | { | |
7f8ecfab | 608 | dev_t dev = MKDEV(VIDEO_MAJOR, 0); |
27a5e6d3 HV |
609 | int ret; |
610 | ||
611 | printk(KERN_INFO "Linux video capture interface: v2.00\n"); | |
7f8ecfab HV |
612 | ret = register_chrdev_region(dev, VIDEO_NUM_DEVICES, VIDEO_NAME); |
613 | if (ret < 0) { | |
614 | printk(KERN_WARNING "videodev: unable to get major %d\n", | |
615 | VIDEO_MAJOR); | |
616 | return ret; | |
27a5e6d3 HV |
617 | } |
618 | ||
619 | ret = class_register(&video_class); | |
620 | if (ret < 0) { | |
7f8ecfab | 621 | unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); |
27a5e6d3 HV |
622 | printk(KERN_WARNING "video_dev: class_register failed\n"); |
623 | return -EIO; | |
624 | } | |
625 | ||
626 | return 0; | |
627 | } | |
628 | ||
629 | static void __exit videodev_exit(void) | |
630 | { | |
7f8ecfab HV |
631 | dev_t dev = MKDEV(VIDEO_MAJOR, 0); |
632 | ||
27a5e6d3 | 633 | class_unregister(&video_class); |
7f8ecfab | 634 | unregister_chrdev_region(dev, VIDEO_NUM_DEVICES); |
27a5e6d3 HV |
635 | } |
636 | ||
637 | module_init(videodev_init) | |
638 | module_exit(videodev_exit) | |
639 | ||
640 | MODULE_AUTHOR("Alan Cox, Mauro Carvalho Chehab <mchehab@infradead.org>"); | |
641 | MODULE_DESCRIPTION("Device registrar for Video4Linux drivers v2"); | |
642 | MODULE_LICENSE("GPL"); | |
cbb72b0f | 643 | MODULE_ALIAS_CHARDEV_MAJOR(VIDEO_MAJOR); |
27a5e6d3 HV |
644 | |
645 | ||
646 | /* | |
647 | * Local variables: | |
648 | * c-basic-offset: 8 | |
649 | * End: | |
650 | */ |