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  *
12  * Authors:	Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1)
13  *              Mauro Carvalho Chehab <mchehab@kernel.org> (version 2)
14  *
15  * Fixes:	20000516  Claudio Matsuoka <claudio@conectiva.com>
16  *		- Added procfs support
17  */
18 
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20 
21 #include <linux/module.h>
22 #include <linux/types.h>
23 #include <linux/kernel.h>
24 #include <linux/mm.h>
25 #include <linux/string.h>
26 #include <linux/errno.h>
27 #include <linux/init.h>
28 #include <linux/kmod.h>
29 #include <linux/slab.h>
30 #include <linux/uaccess.h>
31 
32 #include <media/v4l2-common.h>
33 #include <media/v4l2-device.h>
34 #include <media/v4l2-ioctl.h>
35 
36 #define VIDEO_NUM_DEVICES	256
37 #define VIDEO_NAME              "video4linux"
38 
39 #define dprintk(fmt, arg...) do {					\
40 		printk(KERN_DEBUG pr_fmt("%s: " fmt),			\
41 		       __func__, ##arg);				\
42 } while (0)
43 
44 
45 /*
46  *	sysfs stuff
47  */
48 
49 static ssize_t index_show(struct device *cd,
50 			  struct device_attribute *attr, char *buf)
51 {
52 	struct video_device *vdev = to_video_device(cd);
53 
54 	return sprintf(buf, "%i\n", vdev->index);
55 }
56 static DEVICE_ATTR_RO(index);
57 
58 static ssize_t dev_debug_show(struct device *cd,
59 			  struct device_attribute *attr, char *buf)
60 {
61 	struct video_device *vdev = to_video_device(cd);
62 
63 	return sprintf(buf, "%i\n", vdev->dev_debug);
64 }
65 
66 static ssize_t dev_debug_store(struct device *cd, struct device_attribute *attr,
67 			  const char *buf, size_t len)
68 {
69 	struct video_device *vdev = to_video_device(cd);
70 	int res = 0;
71 	u16 value;
72 
73 	res = kstrtou16(buf, 0, &value);
74 	if (res)
75 		return res;
76 
77 	vdev->dev_debug = value;
78 	return len;
79 }
80 static DEVICE_ATTR_RW(dev_debug);
81 
82 static ssize_t name_show(struct device *cd,
83 			 struct device_attribute *attr, char *buf)
84 {
85 	struct video_device *vdev = to_video_device(cd);
86 
87 	return sprintf(buf, "%.*s\n", (int)sizeof(vdev->name), vdev->name);
88 }
89 static DEVICE_ATTR_RO(name);
90 
91 static struct attribute *video_device_attrs[] = {
92 	&dev_attr_name.attr,
93 	&dev_attr_dev_debug.attr,
94 	&dev_attr_index.attr,
95 	NULL,
96 };
97 ATTRIBUTE_GROUPS(video_device);
98 
99 /*
100  *	Active devices
101  */
102 static struct video_device *video_devices[VIDEO_NUM_DEVICES];
103 static DEFINE_MUTEX(videodev_lock);
104 static DECLARE_BITMAP(devnode_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES);
105 
106 /* Device node utility functions */
107 
108 /* Note: these utility functions all assume that vfl_type is in the range
109    [0, VFL_TYPE_MAX-1]. */
110 
111 #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
112 /* Return the bitmap corresponding to vfl_type. */
113 static inline unsigned long *devnode_bits(enum vfl_devnode_type vfl_type)
114 {
115 	/* Any types not assigned to fixed minor ranges must be mapped to
116 	   one single bitmap for the purposes of finding a free node number
117 	   since all those unassigned types use the same minor range. */
118 	int idx = (vfl_type > VFL_TYPE_RADIO) ? VFL_TYPE_MAX - 1 : vfl_type;
119 
120 	return devnode_nums[idx];
121 }
122 #else
123 /* Return the bitmap corresponding to vfl_type. */
124 static inline unsigned long *devnode_bits(enum vfl_devnode_type vfl_type)
125 {
126 	return devnode_nums[vfl_type];
127 }
128 #endif
129 
130 /* Mark device node number vdev->num as used */
131 static inline void devnode_set(struct video_device *vdev)
132 {
133 	set_bit(vdev->num, devnode_bits(vdev->vfl_type));
134 }
135 
136 /* Mark device node number vdev->num as unused */
137 static inline void devnode_clear(struct video_device *vdev)
138 {
139 	clear_bit(vdev->num, devnode_bits(vdev->vfl_type));
140 }
141 
142 /* Try to find a free device node number in the range [from, to> */
143 static inline int devnode_find(struct video_device *vdev, int from, int to)
144 {
145 	return find_next_zero_bit(devnode_bits(vdev->vfl_type), to, from);
146 }
147 
148 struct video_device *video_device_alloc(void)
149 {
150 	return kzalloc(sizeof(struct video_device), GFP_KERNEL);
151 }
152 EXPORT_SYMBOL(video_device_alloc);
153 
154 void video_device_release(struct video_device *vdev)
155 {
156 	kfree(vdev);
157 }
158 EXPORT_SYMBOL(video_device_release);
159 
160 void video_device_release_empty(struct video_device *vdev)
161 {
162 	/* Do nothing */
163 	/* Only valid when the video_device struct is a static. */
164 }
165 EXPORT_SYMBOL(video_device_release_empty);
166 
167 static inline void video_get(struct video_device *vdev)
168 {
169 	get_device(&vdev->dev);
170 }
171 
172 static inline void video_put(struct video_device *vdev)
173 {
174 	put_device(&vdev->dev);
175 }
176 
177 /* Called when the last user of the video device exits. */
178 static void v4l2_device_release(struct device *cd)
179 {
180 	struct video_device *vdev = to_video_device(cd);
181 	struct v4l2_device *v4l2_dev = vdev->v4l2_dev;
182 
183 	mutex_lock(&videodev_lock);
184 	if (WARN_ON(video_devices[vdev->minor] != vdev)) {
185 		/* should not happen */
186 		mutex_unlock(&videodev_lock);
187 		return;
188 	}
189 
190 	/* Free up this device for reuse */
191 	video_devices[vdev->minor] = NULL;
192 
193 	/* Delete the cdev on this minor as well */
194 	cdev_del(vdev->cdev);
195 	/* Just in case some driver tries to access this from
196 	   the release() callback. */
197 	vdev->cdev = NULL;
198 
199 	/* Mark device node number as free */
200 	devnode_clear(vdev);
201 
202 	mutex_unlock(&videodev_lock);
203 
204 #if defined(CONFIG_MEDIA_CONTROLLER)
205 	if (v4l2_dev->mdev) {
206 		/* Remove interfaces and interface links */
207 		media_devnode_remove(vdev->intf_devnode);
208 		if (vdev->entity.function != MEDIA_ENT_F_UNKNOWN)
209 			media_device_unregister_entity(&vdev->entity);
210 	}
211 #endif
212 
213 	/* Do not call v4l2_device_put if there is no release callback set.
214 	 * Drivers that have no v4l2_device release callback might free the
215 	 * v4l2_dev instance in the video_device release callback below, so we
216 	 * must perform this check here.
217 	 *
218 	 * TODO: In the long run all drivers that use v4l2_device should use the
219 	 * v4l2_device release callback. This check will then be unnecessary.
220 	 */
221 	if (v4l2_dev->release == NULL)
222 		v4l2_dev = NULL;
223 
224 	/* Release video_device and perform other
225 	   cleanups as needed. */
226 	vdev->release(vdev);
227 
228 	/* Decrease v4l2_device refcount */
229 	if (v4l2_dev)
230 		v4l2_device_put(v4l2_dev);
231 }
232 
233 static struct class video_class = {
234 	.name = VIDEO_NAME,
235 	.dev_groups = video_device_groups,
236 };
237 
238 struct video_device *video_devdata(struct file *file)
239 {
240 	return video_devices[iminor(file_inode(file))];
241 }
242 EXPORT_SYMBOL(video_devdata);
243 
244 
245 /* Priority handling */
246 
247 static inline bool prio_is_valid(enum v4l2_priority prio)
248 {
249 	return prio == V4L2_PRIORITY_BACKGROUND ||
250 	       prio == V4L2_PRIORITY_INTERACTIVE ||
251 	       prio == V4L2_PRIORITY_RECORD;
252 }
253 
254 void v4l2_prio_init(struct v4l2_prio_state *global)
255 {
256 	memset(global, 0, sizeof(*global));
257 }
258 EXPORT_SYMBOL(v4l2_prio_init);
259 
260 int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
261 		     enum v4l2_priority new)
262 {
263 	if (!prio_is_valid(new))
264 		return -EINVAL;
265 	if (*local == new)
266 		return 0;
267 
268 	atomic_inc(&global->prios[new]);
269 	if (prio_is_valid(*local))
270 		atomic_dec(&global->prios[*local]);
271 	*local = new;
272 	return 0;
273 }
274 EXPORT_SYMBOL(v4l2_prio_change);
275 
276 void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local)
277 {
278 	v4l2_prio_change(global, local, V4L2_PRIORITY_DEFAULT);
279 }
280 EXPORT_SYMBOL(v4l2_prio_open);
281 
282 void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local)
283 {
284 	if (prio_is_valid(local))
285 		atomic_dec(&global->prios[local]);
286 }
287 EXPORT_SYMBOL(v4l2_prio_close);
288 
289 enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global)
290 {
291 	if (atomic_read(&global->prios[V4L2_PRIORITY_RECORD]) > 0)
292 		return V4L2_PRIORITY_RECORD;
293 	if (atomic_read(&global->prios[V4L2_PRIORITY_INTERACTIVE]) > 0)
294 		return V4L2_PRIORITY_INTERACTIVE;
295 	if (atomic_read(&global->prios[V4L2_PRIORITY_BACKGROUND]) > 0)
296 		return V4L2_PRIORITY_BACKGROUND;
297 	return V4L2_PRIORITY_UNSET;
298 }
299 EXPORT_SYMBOL(v4l2_prio_max);
300 
301 int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local)
302 {
303 	return (local < v4l2_prio_max(global)) ? -EBUSY : 0;
304 }
305 EXPORT_SYMBOL(v4l2_prio_check);
306 
307 
308 static ssize_t v4l2_read(struct file *filp, char __user *buf,
309 		size_t sz, loff_t *off)
310 {
311 	struct video_device *vdev = video_devdata(filp);
312 	int ret = -ENODEV;
313 
314 	if (!vdev->fops->read)
315 		return -EINVAL;
316 	if (video_is_registered(vdev))
317 		ret = vdev->fops->read(filp, buf, sz, off);
318 	if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
319 	    (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
320 		dprintk("%s: read: %zd (%d)\n",
321 			video_device_node_name(vdev), sz, ret);
322 	return ret;
323 }
324 
325 static ssize_t v4l2_write(struct file *filp, const char __user *buf,
326 		size_t sz, loff_t *off)
327 {
328 	struct video_device *vdev = video_devdata(filp);
329 	int ret = -ENODEV;
330 
331 	if (!vdev->fops->write)
332 		return -EINVAL;
333 	if (video_is_registered(vdev))
334 		ret = vdev->fops->write(filp, buf, sz, off);
335 	if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
336 	    (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
337 		dprintk("%s: write: %zd (%d)\n",
338 			video_device_node_name(vdev), sz, ret);
339 	return ret;
340 }
341 
342 static __poll_t v4l2_poll(struct file *filp, struct poll_table_struct *poll)
343 {
344 	struct video_device *vdev = video_devdata(filp);
345 	__poll_t res = EPOLLERR | EPOLLHUP;
346 
347 	if (!vdev->fops->poll)
348 		return DEFAULT_POLLMASK;
349 	if (video_is_registered(vdev))
350 		res = vdev->fops->poll(filp, poll);
351 	if (vdev->dev_debug & V4L2_DEV_DEBUG_POLL)
352 		dprintk("%s: poll: %08x\n",
353 			video_device_node_name(vdev), res);
354 	return res;
355 }
356 
357 static long v4l2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
358 {
359 	struct video_device *vdev = video_devdata(filp);
360 	int ret = -ENODEV;
361 
362 	if (vdev->fops->unlocked_ioctl) {
363 		if (video_is_registered(vdev))
364 			ret = vdev->fops->unlocked_ioctl(filp, cmd, arg);
365 	} else
366 		ret = -ENOTTY;
367 
368 	return ret;
369 }
370 
371 #ifdef CONFIG_MMU
372 #define v4l2_get_unmapped_area NULL
373 #else
374 static unsigned long v4l2_get_unmapped_area(struct file *filp,
375 		unsigned long addr, unsigned long len, unsigned long pgoff,
376 		unsigned long flags)
377 {
378 	struct video_device *vdev = video_devdata(filp);
379 	int ret;
380 
381 	if (!vdev->fops->get_unmapped_area)
382 		return -ENOSYS;
383 	if (!video_is_registered(vdev))
384 		return -ENODEV;
385 	ret = vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags);
386 	if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
387 		dprintk("%s: get_unmapped_area (%d)\n",
388 			video_device_node_name(vdev), ret);
389 	return ret;
390 }
391 #endif
392 
393 static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm)
394 {
395 	struct video_device *vdev = video_devdata(filp);
396 	int ret = -ENODEV;
397 
398 	if (!vdev->fops->mmap)
399 		return -ENODEV;
400 	if (video_is_registered(vdev))
401 		ret = vdev->fops->mmap(filp, vm);
402 	if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
403 		dprintk("%s: mmap (%d)\n",
404 			video_device_node_name(vdev), ret);
405 	return ret;
406 }
407 
408 /* Override for the open function */
409 static int v4l2_open(struct inode *inode, struct file *filp)
410 {
411 	struct video_device *vdev;
412 	int ret = 0;
413 
414 	/* Check if the video device is available */
415 	mutex_lock(&videodev_lock);
416 	vdev = video_devdata(filp);
417 	/* return ENODEV if the video device has already been removed. */
418 	if (vdev == NULL || !video_is_registered(vdev)) {
419 		mutex_unlock(&videodev_lock);
420 		return -ENODEV;
421 	}
422 	/* and increase the device refcount */
423 	video_get(vdev);
424 	mutex_unlock(&videodev_lock);
425 	if (vdev->fops->open) {
426 		if (video_is_registered(vdev))
427 			ret = vdev->fops->open(filp);
428 		else
429 			ret = -ENODEV;
430 	}
431 
432 	if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
433 		dprintk("%s: open (%d)\n",
434 			video_device_node_name(vdev), ret);
435 	/* decrease the refcount in case of an error */
436 	if (ret)
437 		video_put(vdev);
438 	return ret;
439 }
440 
441 /* Override for the release function */
442 static int v4l2_release(struct inode *inode, struct file *filp)
443 {
444 	struct video_device *vdev = video_devdata(filp);
445 	int ret = 0;
446 
447 	if (vdev->fops->release)
448 		ret = vdev->fops->release(filp);
449 	if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
450 		dprintk("%s: release\n",
451 			video_device_node_name(vdev));
452 
453 	/* decrease the refcount unconditionally since the release()
454 	   return value is ignored. */
455 	video_put(vdev);
456 	return ret;
457 }
458 
459 static const struct file_operations v4l2_fops = {
460 	.owner = THIS_MODULE,
461 	.read = v4l2_read,
462 	.write = v4l2_write,
463 	.open = v4l2_open,
464 	.get_unmapped_area = v4l2_get_unmapped_area,
465 	.mmap = v4l2_mmap,
466 	.unlocked_ioctl = v4l2_ioctl,
467 #ifdef CONFIG_COMPAT
468 	.compat_ioctl = v4l2_compat_ioctl32,
469 #endif
470 	.release = v4l2_release,
471 	.poll = v4l2_poll,
472 	.llseek = no_llseek,
473 };
474 
475 /**
476  * get_index - assign stream index number based on v4l2_dev
477  * @vdev: video_device to assign index number to, vdev->v4l2_dev should be assigned
478  *
479  * Note that when this is called the new device has not yet been registered
480  * in the video_device array, but it was able to obtain a minor number.
481  *
482  * This means that we can always obtain a free stream index number since
483  * the worst case scenario is that there are VIDEO_NUM_DEVICES - 1 slots in
484  * use of the video_device array.
485  *
486  * Returns a free index number.
487  */
488 static int get_index(struct video_device *vdev)
489 {
490 	/* This can be static since this function is called with the global
491 	   videodev_lock held. */
492 	static DECLARE_BITMAP(used, VIDEO_NUM_DEVICES);
493 	int i;
494 
495 	bitmap_zero(used, VIDEO_NUM_DEVICES);
496 
497 	for (i = 0; i < VIDEO_NUM_DEVICES; i++) {
498 		if (video_devices[i] != NULL &&
499 		    video_devices[i]->v4l2_dev == vdev->v4l2_dev) {
500 			set_bit(video_devices[i]->index, used);
501 		}
502 	}
503 
504 	return find_first_zero_bit(used, VIDEO_NUM_DEVICES);
505 }
506 
507 #define SET_VALID_IOCTL(ops, cmd, op)			\
508 	if (ops->op)					\
509 		set_bit(_IOC_NR(cmd), valid_ioctls)
510 
511 /* This determines which ioctls are actually implemented in the driver.
512    It's a one-time thing which simplifies video_ioctl2 as it can just do
513    a bit test.
514 
515    Note that drivers can override this by setting bits to 1 in
516    vdev->valid_ioctls. If an ioctl is marked as 1 when this function is
517    called, then that ioctl will actually be marked as unimplemented.
518 
519    It does that by first setting up the local valid_ioctls bitmap, and
520    at the end do a:
521 
522    vdev->valid_ioctls = valid_ioctls & ~(vdev->valid_ioctls)
523  */
524 static void determine_valid_ioctls(struct video_device *vdev)
525 {
526 	DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE);
527 	const struct v4l2_ioctl_ops *ops = vdev->ioctl_ops;
528 	bool is_vid = vdev->vfl_type == VFL_TYPE_GRABBER;
529 	bool is_vbi = vdev->vfl_type == VFL_TYPE_VBI;
530 	bool is_radio = vdev->vfl_type == VFL_TYPE_RADIO;
531 	bool is_sdr = vdev->vfl_type == VFL_TYPE_SDR;
532 	bool is_tch = vdev->vfl_type == VFL_TYPE_TOUCH;
533 	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
534 	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
535 
536 	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
537 
538 	/* vfl_type and vfl_dir independent ioctls */
539 
540 	SET_VALID_IOCTL(ops, VIDIOC_QUERYCAP, vidioc_querycap);
541 	set_bit(_IOC_NR(VIDIOC_G_PRIORITY), valid_ioctls);
542 	set_bit(_IOC_NR(VIDIOC_S_PRIORITY), valid_ioctls);
543 
544 	/* Note: the control handler can also be passed through the filehandle,
545 	   and that can't be tested here. If the bit for these control ioctls
546 	   is set, then the ioctl is valid. But if it is 0, then it can still
547 	   be valid if the filehandle passed the control handler. */
548 	if (vdev->ctrl_handler || ops->vidioc_queryctrl)
549 		set_bit(_IOC_NR(VIDIOC_QUERYCTRL), valid_ioctls);
550 	if (vdev->ctrl_handler || ops->vidioc_query_ext_ctrl)
551 		set_bit(_IOC_NR(VIDIOC_QUERY_EXT_CTRL), valid_ioctls);
552 	if (vdev->ctrl_handler || ops->vidioc_g_ctrl || ops->vidioc_g_ext_ctrls)
553 		set_bit(_IOC_NR(VIDIOC_G_CTRL), valid_ioctls);
554 	if (vdev->ctrl_handler || ops->vidioc_s_ctrl || ops->vidioc_s_ext_ctrls)
555 		set_bit(_IOC_NR(VIDIOC_S_CTRL), valid_ioctls);
556 	if (vdev->ctrl_handler || ops->vidioc_g_ext_ctrls)
557 		set_bit(_IOC_NR(VIDIOC_G_EXT_CTRLS), valid_ioctls);
558 	if (vdev->ctrl_handler || ops->vidioc_s_ext_ctrls)
559 		set_bit(_IOC_NR(VIDIOC_S_EXT_CTRLS), valid_ioctls);
560 	if (vdev->ctrl_handler || ops->vidioc_try_ext_ctrls)
561 		set_bit(_IOC_NR(VIDIOC_TRY_EXT_CTRLS), valid_ioctls);
562 	if (vdev->ctrl_handler || ops->vidioc_querymenu)
563 		set_bit(_IOC_NR(VIDIOC_QUERYMENU), valid_ioctls);
564 	SET_VALID_IOCTL(ops, VIDIOC_G_FREQUENCY, vidioc_g_frequency);
565 	SET_VALID_IOCTL(ops, VIDIOC_S_FREQUENCY, vidioc_s_frequency);
566 	SET_VALID_IOCTL(ops, VIDIOC_LOG_STATUS, vidioc_log_status);
567 #ifdef CONFIG_VIDEO_ADV_DEBUG
568 	set_bit(_IOC_NR(VIDIOC_DBG_G_CHIP_INFO), valid_ioctls);
569 	set_bit(_IOC_NR(VIDIOC_DBG_G_REGISTER), valid_ioctls);
570 	set_bit(_IOC_NR(VIDIOC_DBG_S_REGISTER), valid_ioctls);
571 #endif
572 	/* yes, really vidioc_subscribe_event */
573 	SET_VALID_IOCTL(ops, VIDIOC_DQEVENT, vidioc_subscribe_event);
574 	SET_VALID_IOCTL(ops, VIDIOC_SUBSCRIBE_EVENT, vidioc_subscribe_event);
575 	SET_VALID_IOCTL(ops, VIDIOC_UNSUBSCRIBE_EVENT, vidioc_unsubscribe_event);
576 	if (ops->vidioc_enum_freq_bands || ops->vidioc_g_tuner || ops->vidioc_g_modulator)
577 		set_bit(_IOC_NR(VIDIOC_ENUM_FREQ_BANDS), valid_ioctls);
578 
579 	if (is_vid || is_tch) {
580 		/* video and metadata specific ioctls */
581 		if ((is_rx && (ops->vidioc_enum_fmt_vid_cap ||
582 			       ops->vidioc_enum_fmt_vid_cap_mplane ||
583 			       ops->vidioc_enum_fmt_vid_overlay ||
584 			       ops->vidioc_enum_fmt_meta_cap)) ||
585 		    (is_tx && (ops->vidioc_enum_fmt_vid_out ||
586 			       ops->vidioc_enum_fmt_vid_out_mplane)))
587 			set_bit(_IOC_NR(VIDIOC_ENUM_FMT), valid_ioctls);
588 		if ((is_rx && (ops->vidioc_g_fmt_vid_cap ||
589 			       ops->vidioc_g_fmt_vid_cap_mplane ||
590 			       ops->vidioc_g_fmt_vid_overlay ||
591 			       ops->vidioc_g_fmt_meta_cap)) ||
592 		    (is_tx && (ops->vidioc_g_fmt_vid_out ||
593 			       ops->vidioc_g_fmt_vid_out_mplane ||
594 			       ops->vidioc_g_fmt_vid_out_overlay)))
595 			 set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
596 		if ((is_rx && (ops->vidioc_s_fmt_vid_cap ||
597 			       ops->vidioc_s_fmt_vid_cap_mplane ||
598 			       ops->vidioc_s_fmt_vid_overlay ||
599 			       ops->vidioc_s_fmt_meta_cap)) ||
600 		    (is_tx && (ops->vidioc_s_fmt_vid_out ||
601 			       ops->vidioc_s_fmt_vid_out_mplane ||
602 			       ops->vidioc_s_fmt_vid_out_overlay)))
603 			 set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
604 		if ((is_rx && (ops->vidioc_try_fmt_vid_cap ||
605 			       ops->vidioc_try_fmt_vid_cap_mplane ||
606 			       ops->vidioc_try_fmt_vid_overlay ||
607 			       ops->vidioc_try_fmt_meta_cap)) ||
608 		    (is_tx && (ops->vidioc_try_fmt_vid_out ||
609 			       ops->vidioc_try_fmt_vid_out_mplane ||
610 			       ops->vidioc_try_fmt_vid_out_overlay)))
611 			 set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
612 		SET_VALID_IOCTL(ops, VIDIOC_OVERLAY, vidioc_overlay);
613 		SET_VALID_IOCTL(ops, VIDIOC_G_FBUF, vidioc_g_fbuf);
614 		SET_VALID_IOCTL(ops, VIDIOC_S_FBUF, vidioc_s_fbuf);
615 		SET_VALID_IOCTL(ops, VIDIOC_G_JPEGCOMP, vidioc_g_jpegcomp);
616 		SET_VALID_IOCTL(ops, VIDIOC_S_JPEGCOMP, vidioc_s_jpegcomp);
617 		SET_VALID_IOCTL(ops, VIDIOC_G_ENC_INDEX, vidioc_g_enc_index);
618 		SET_VALID_IOCTL(ops, VIDIOC_ENCODER_CMD, vidioc_encoder_cmd);
619 		SET_VALID_IOCTL(ops, VIDIOC_TRY_ENCODER_CMD, vidioc_try_encoder_cmd);
620 		SET_VALID_IOCTL(ops, VIDIOC_DECODER_CMD, vidioc_decoder_cmd);
621 		SET_VALID_IOCTL(ops, VIDIOC_TRY_DECODER_CMD, vidioc_try_decoder_cmd);
622 		SET_VALID_IOCTL(ops, VIDIOC_ENUM_FRAMESIZES, vidioc_enum_framesizes);
623 		SET_VALID_IOCTL(ops, VIDIOC_ENUM_FRAMEINTERVALS, vidioc_enum_frameintervals);
624 		if (ops->vidioc_g_crop || ops->vidioc_g_selection)
625 			set_bit(_IOC_NR(VIDIOC_G_CROP), valid_ioctls);
626 		if (ops->vidioc_s_crop || ops->vidioc_s_selection)
627 			set_bit(_IOC_NR(VIDIOC_S_CROP), valid_ioctls);
628 		SET_VALID_IOCTL(ops, VIDIOC_G_SELECTION, vidioc_g_selection);
629 		SET_VALID_IOCTL(ops, VIDIOC_S_SELECTION, vidioc_s_selection);
630 		if (ops->vidioc_cropcap || ops->vidioc_g_selection)
631 			set_bit(_IOC_NR(VIDIOC_CROPCAP), valid_ioctls);
632 	} else if (is_vbi) {
633 		/* vbi specific ioctls */
634 		if ((is_rx && (ops->vidioc_g_fmt_vbi_cap ||
635 			       ops->vidioc_g_fmt_sliced_vbi_cap)) ||
636 		    (is_tx && (ops->vidioc_g_fmt_vbi_out ||
637 			       ops->vidioc_g_fmt_sliced_vbi_out)))
638 			set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
639 		if ((is_rx && (ops->vidioc_s_fmt_vbi_cap ||
640 			       ops->vidioc_s_fmt_sliced_vbi_cap)) ||
641 		    (is_tx && (ops->vidioc_s_fmt_vbi_out ||
642 			       ops->vidioc_s_fmt_sliced_vbi_out)))
643 			set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
644 		if ((is_rx && (ops->vidioc_try_fmt_vbi_cap ||
645 			       ops->vidioc_try_fmt_sliced_vbi_cap)) ||
646 		    (is_tx && (ops->vidioc_try_fmt_vbi_out ||
647 			       ops->vidioc_try_fmt_sliced_vbi_out)))
648 			set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
649 		SET_VALID_IOCTL(ops, VIDIOC_G_SLICED_VBI_CAP, vidioc_g_sliced_vbi_cap);
650 	} else if (is_sdr && is_rx) {
651 		/* SDR receiver specific ioctls */
652 		if (ops->vidioc_enum_fmt_sdr_cap)
653 			set_bit(_IOC_NR(VIDIOC_ENUM_FMT), valid_ioctls);
654 		if (ops->vidioc_g_fmt_sdr_cap)
655 			set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
656 		if (ops->vidioc_s_fmt_sdr_cap)
657 			set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
658 		if (ops->vidioc_try_fmt_sdr_cap)
659 			set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
660 	} else if (is_sdr && is_tx) {
661 		/* SDR transmitter specific ioctls */
662 		if (ops->vidioc_enum_fmt_sdr_out)
663 			set_bit(_IOC_NR(VIDIOC_ENUM_FMT), valid_ioctls);
664 		if (ops->vidioc_g_fmt_sdr_out)
665 			set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
666 		if (ops->vidioc_s_fmt_sdr_out)
667 			set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
668 		if (ops->vidioc_try_fmt_sdr_out)
669 			set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
670 	}
671 
672 	if (is_vid || is_vbi || is_sdr || is_tch) {
673 		/* ioctls valid for video, metadata, vbi or sdr */
674 		SET_VALID_IOCTL(ops, VIDIOC_REQBUFS, vidioc_reqbufs);
675 		SET_VALID_IOCTL(ops, VIDIOC_QUERYBUF, vidioc_querybuf);
676 		SET_VALID_IOCTL(ops, VIDIOC_QBUF, vidioc_qbuf);
677 		SET_VALID_IOCTL(ops, VIDIOC_EXPBUF, vidioc_expbuf);
678 		SET_VALID_IOCTL(ops, VIDIOC_DQBUF, vidioc_dqbuf);
679 		SET_VALID_IOCTL(ops, VIDIOC_CREATE_BUFS, vidioc_create_bufs);
680 		SET_VALID_IOCTL(ops, VIDIOC_PREPARE_BUF, vidioc_prepare_buf);
681 		SET_VALID_IOCTL(ops, VIDIOC_STREAMON, vidioc_streamon);
682 		SET_VALID_IOCTL(ops, VIDIOC_STREAMOFF, vidioc_streamoff);
683 	}
684 
685 	if (is_vid || is_vbi || is_tch) {
686 		/* ioctls valid for video or vbi */
687 		if (ops->vidioc_s_std)
688 			set_bit(_IOC_NR(VIDIOC_ENUMSTD), valid_ioctls);
689 		SET_VALID_IOCTL(ops, VIDIOC_S_STD, vidioc_s_std);
690 		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
691 		if (is_rx) {
692 			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
693 			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
694 			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
695 			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
696 			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
697 			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
698 			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
699 			SET_VALID_IOCTL(ops, VIDIOC_QUERY_DV_TIMINGS, vidioc_query_dv_timings);
700 			SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
701 		}
702 		if (is_tx) {
703 			SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
704 			SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
705 			SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
706 			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
707 			SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
708 			SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
709 		}
710 		if (ops->vidioc_g_parm || (vdev->vfl_type == VFL_TYPE_GRABBER &&
711 					ops->vidioc_g_std))
712 			set_bit(_IOC_NR(VIDIOC_G_PARM), valid_ioctls);
713 		SET_VALID_IOCTL(ops, VIDIOC_S_PARM, vidioc_s_parm);
714 		SET_VALID_IOCTL(ops, VIDIOC_S_DV_TIMINGS, vidioc_s_dv_timings);
715 		SET_VALID_IOCTL(ops, VIDIOC_G_DV_TIMINGS, vidioc_g_dv_timings);
716 		SET_VALID_IOCTL(ops, VIDIOC_ENUM_DV_TIMINGS, vidioc_enum_dv_timings);
717 		SET_VALID_IOCTL(ops, VIDIOC_DV_TIMINGS_CAP, vidioc_dv_timings_cap);
718 		SET_VALID_IOCTL(ops, VIDIOC_G_EDID, vidioc_g_edid);
719 	}
720 	if (is_tx && (is_radio || is_sdr)) {
721 		/* radio transmitter only ioctls */
722 		SET_VALID_IOCTL(ops, VIDIOC_G_MODULATOR, vidioc_g_modulator);
723 		SET_VALID_IOCTL(ops, VIDIOC_S_MODULATOR, vidioc_s_modulator);
724 	}
725 	if (is_rx) {
726 		/* receiver only ioctls */
727 		SET_VALID_IOCTL(ops, VIDIOC_G_TUNER, vidioc_g_tuner);
728 		SET_VALID_IOCTL(ops, VIDIOC_S_TUNER, vidioc_s_tuner);
729 		SET_VALID_IOCTL(ops, VIDIOC_S_HW_FREQ_SEEK, vidioc_s_hw_freq_seek);
730 	}
731 
732 	bitmap_andnot(vdev->valid_ioctls, valid_ioctls, vdev->valid_ioctls,
733 			BASE_VIDIOC_PRIVATE);
734 }
735 
736 static int video_register_media_controller(struct video_device *vdev, int type)
737 {
738 #if defined(CONFIG_MEDIA_CONTROLLER)
739 	u32 intf_type;
740 	int ret;
741 
742 	if (!vdev->v4l2_dev->mdev)
743 		return 0;
744 
745 	vdev->entity.obj_type = MEDIA_ENTITY_TYPE_VIDEO_DEVICE;
746 	vdev->entity.function = MEDIA_ENT_F_UNKNOWN;
747 
748 	switch (type) {
749 	case VFL_TYPE_GRABBER:
750 		intf_type = MEDIA_INTF_T_V4L_VIDEO;
751 		vdev->entity.function = MEDIA_ENT_F_IO_V4L;
752 		break;
753 	case VFL_TYPE_VBI:
754 		intf_type = MEDIA_INTF_T_V4L_VBI;
755 		vdev->entity.function = MEDIA_ENT_F_IO_VBI;
756 		break;
757 	case VFL_TYPE_SDR:
758 		intf_type = MEDIA_INTF_T_V4L_SWRADIO;
759 		vdev->entity.function = MEDIA_ENT_F_IO_SWRADIO;
760 		break;
761 	case VFL_TYPE_TOUCH:
762 		intf_type = MEDIA_INTF_T_V4L_TOUCH;
763 		vdev->entity.function = MEDIA_ENT_F_IO_V4L;
764 		break;
765 	case VFL_TYPE_RADIO:
766 		intf_type = MEDIA_INTF_T_V4L_RADIO;
767 		/*
768 		 * Radio doesn't have an entity at the V4L2 side to represent
769 		 * radio input or output. Instead, the audio input/output goes
770 		 * via either physical wires or ALSA.
771 		 */
772 		break;
773 	case VFL_TYPE_SUBDEV:
774 		intf_type = MEDIA_INTF_T_V4L_SUBDEV;
775 		/* Entity will be created via v4l2_device_register_subdev() */
776 		break;
777 	default:
778 		return 0;
779 	}
780 
781 	if (vdev->entity.function != MEDIA_ENT_F_UNKNOWN) {
782 		vdev->entity.name = vdev->name;
783 
784 		/* Needed just for backward compatibility with legacy MC API */
785 		vdev->entity.info.dev.major = VIDEO_MAJOR;
786 		vdev->entity.info.dev.minor = vdev->minor;
787 
788 		ret = media_device_register_entity(vdev->v4l2_dev->mdev,
789 						   &vdev->entity);
790 		if (ret < 0) {
791 			pr_warn("%s: media_device_register_entity failed\n",
792 				__func__);
793 			return ret;
794 		}
795 	}
796 
797 	vdev->intf_devnode = media_devnode_create(vdev->v4l2_dev->mdev,
798 						  intf_type,
799 						  0, VIDEO_MAJOR,
800 						  vdev->minor);
801 	if (!vdev->intf_devnode) {
802 		media_device_unregister_entity(&vdev->entity);
803 		return -ENOMEM;
804 	}
805 
806 	if (vdev->entity.function != MEDIA_ENT_F_UNKNOWN) {
807 		struct media_link *link;
808 
809 		link = media_create_intf_link(&vdev->entity,
810 					      &vdev->intf_devnode->intf,
811 					      MEDIA_LNK_FL_ENABLED);
812 		if (!link) {
813 			media_devnode_remove(vdev->intf_devnode);
814 			media_device_unregister_entity(&vdev->entity);
815 			return -ENOMEM;
816 		}
817 	}
818 
819 	/* FIXME: how to create the other interface links? */
820 
821 #endif
822 	return 0;
823 }
824 
825 int __video_register_device(struct video_device *vdev,
826 			    enum vfl_devnode_type type,
827 			    int nr, int warn_if_nr_in_use,
828 			    struct module *owner)
829 {
830 	int i = 0;
831 	int ret;
832 	int minor_offset = 0;
833 	int minor_cnt = VIDEO_NUM_DEVICES;
834 	const char *name_base;
835 
836 	/* A minor value of -1 marks this video device as never
837 	   having been registered */
838 	vdev->minor = -1;
839 
840 	/* the release callback MUST be present */
841 	if (WARN_ON(!vdev->release))
842 		return -EINVAL;
843 	/* the v4l2_dev pointer MUST be present */
844 	if (WARN_ON(!vdev->v4l2_dev))
845 		return -EINVAL;
846 
847 	/* v4l2_fh support */
848 	spin_lock_init(&vdev->fh_lock);
849 	INIT_LIST_HEAD(&vdev->fh_list);
850 
851 	/* Part 1: check device type */
852 	switch (type) {
853 	case VFL_TYPE_GRABBER:
854 		name_base = "video";
855 		break;
856 	case VFL_TYPE_VBI:
857 		name_base = "vbi";
858 		break;
859 	case VFL_TYPE_RADIO:
860 		name_base = "radio";
861 		break;
862 	case VFL_TYPE_SUBDEV:
863 		name_base = "v4l-subdev";
864 		break;
865 	case VFL_TYPE_SDR:
866 		/* Use device name 'swradio' because 'sdr' was already taken. */
867 		name_base = "swradio";
868 		break;
869 	case VFL_TYPE_TOUCH:
870 		name_base = "v4l-touch";
871 		break;
872 	default:
873 		pr_err("%s called with unknown type: %d\n",
874 		       __func__, type);
875 		return -EINVAL;
876 	}
877 
878 	vdev->vfl_type = type;
879 	vdev->cdev = NULL;
880 	if (vdev->dev_parent == NULL)
881 		vdev->dev_parent = vdev->v4l2_dev->dev;
882 	if (vdev->ctrl_handler == NULL)
883 		vdev->ctrl_handler = vdev->v4l2_dev->ctrl_handler;
884 	/* If the prio state pointer is NULL, then use the v4l2_device
885 	   prio state. */
886 	if (vdev->prio == NULL)
887 		vdev->prio = &vdev->v4l2_dev->prio;
888 
889 	/* Part 2: find a free minor, device node number and device index. */
890 #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
891 	/* Keep the ranges for the first four types for historical
892 	 * reasons.
893 	 * Newer devices (not yet in place) should use the range
894 	 * of 128-191 and just pick the first free minor there
895 	 * (new style). */
896 	switch (type) {
897 	case VFL_TYPE_GRABBER:
898 		minor_offset = 0;
899 		minor_cnt = 64;
900 		break;
901 	case VFL_TYPE_RADIO:
902 		minor_offset = 64;
903 		minor_cnt = 64;
904 		break;
905 	case VFL_TYPE_VBI:
906 		minor_offset = 224;
907 		minor_cnt = 32;
908 		break;
909 	default:
910 		minor_offset = 128;
911 		minor_cnt = 64;
912 		break;
913 	}
914 #endif
915 
916 	/* Pick a device node number */
917 	mutex_lock(&videodev_lock);
918 	nr = devnode_find(vdev, nr == -1 ? 0 : nr, minor_cnt);
919 	if (nr == minor_cnt)
920 		nr = devnode_find(vdev, 0, minor_cnt);
921 	if (nr == minor_cnt) {
922 		pr_err("could not get a free device node number\n");
923 		mutex_unlock(&videodev_lock);
924 		return -ENFILE;
925 	}
926 #ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
927 	/* 1-on-1 mapping of device node number to minor number */
928 	i = nr;
929 #else
930 	/* The device node number and minor numbers are independent, so
931 	   we just find the first free minor number. */
932 	for (i = 0; i < VIDEO_NUM_DEVICES; i++)
933 		if (video_devices[i] == NULL)
934 			break;
935 	if (i == VIDEO_NUM_DEVICES) {
936 		mutex_unlock(&videodev_lock);
937 		pr_err("could not get a free minor\n");
938 		return -ENFILE;
939 	}
940 #endif
941 	vdev->minor = i + minor_offset;
942 	vdev->num = nr;
943 
944 	/* Should not happen since we thought this minor was free */
945 	if (WARN_ON(video_devices[vdev->minor])) {
946 		mutex_unlock(&videodev_lock);
947 		pr_err("video_device not empty!\n");
948 		return -ENFILE;
949 	}
950 	devnode_set(vdev);
951 	vdev->index = get_index(vdev);
952 	video_devices[vdev->minor] = vdev;
953 	mutex_unlock(&videodev_lock);
954 
955 	if (vdev->ioctl_ops)
956 		determine_valid_ioctls(vdev);
957 
958 	/* Part 3: Initialize the character device */
959 	vdev->cdev = cdev_alloc();
960 	if (vdev->cdev == NULL) {
961 		ret = -ENOMEM;
962 		goto cleanup;
963 	}
964 	vdev->cdev->ops = &v4l2_fops;
965 	vdev->cdev->owner = owner;
966 	ret = cdev_add(vdev->cdev, MKDEV(VIDEO_MAJOR, vdev->minor), 1);
967 	if (ret < 0) {
968 		pr_err("%s: cdev_add failed\n", __func__);
969 		kfree(vdev->cdev);
970 		vdev->cdev = NULL;
971 		goto cleanup;
972 	}
973 
974 	/* Part 4: register the device with sysfs */
975 	vdev->dev.class = &video_class;
976 	vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor);
977 	vdev->dev.parent = vdev->dev_parent;
978 	dev_set_name(&vdev->dev, "%s%d", name_base, vdev->num);
979 	ret = device_register(&vdev->dev);
980 	if (ret < 0) {
981 		pr_err("%s: device_register failed\n", __func__);
982 		goto cleanup;
983 	}
984 	/* Register the release callback that will be called when the last
985 	   reference to the device goes away. */
986 	vdev->dev.release = v4l2_device_release;
987 
988 	if (nr != -1 && nr != vdev->num && warn_if_nr_in_use)
989 		pr_warn("%s: requested %s%d, got %s\n", __func__,
990 			name_base, nr, video_device_node_name(vdev));
991 
992 	/* Increase v4l2_device refcount */
993 	v4l2_device_get(vdev->v4l2_dev);
994 
995 	/* Part 5: Register the entity. */
996 	ret = video_register_media_controller(vdev, type);
997 
998 	/* Part 6: Activate this minor. The char device can now be used. */
999 	set_bit(V4L2_FL_REGISTERED, &vdev->flags);
1000 
1001 	return 0;
1002 
1003 cleanup:
1004 	mutex_lock(&videodev_lock);
1005 	if (vdev->cdev)
1006 		cdev_del(vdev->cdev);
1007 	video_devices[vdev->minor] = NULL;
1008 	devnode_clear(vdev);
1009 	mutex_unlock(&videodev_lock);
1010 	/* Mark this video device as never having been registered. */
1011 	vdev->minor = -1;
1012 	return ret;
1013 }
1014 EXPORT_SYMBOL(__video_register_device);
1015 
1016 /**
1017  *	video_unregister_device - unregister a video4linux device
1018  *	@vdev: the device to unregister
1019  *
1020  *	This unregisters the passed device. Future open calls will
1021  *	be met with errors.
1022  */
1023 void video_unregister_device(struct video_device *vdev)
1024 {
1025 	/* Check if vdev was ever registered at all */
1026 	if (!vdev || !video_is_registered(vdev))
1027 		return;
1028 
1029 	mutex_lock(&videodev_lock);
1030 	/* This must be in a critical section to prevent a race with v4l2_open.
1031 	 * Once this bit has been cleared video_get may never be called again.
1032 	 */
1033 	clear_bit(V4L2_FL_REGISTERED, &vdev->flags);
1034 	mutex_unlock(&videodev_lock);
1035 	device_unregister(&vdev->dev);
1036 }
1037 EXPORT_SYMBOL(video_unregister_device);
1038 
1039 /*
1040  *	Initialise video for linux
1041  */
1042 static int __init videodev_init(void)
1043 {
1044 	dev_t dev = MKDEV(VIDEO_MAJOR, 0);
1045 	int ret;
1046 
1047 	pr_info("Linux video capture interface: v2.00\n");
1048 	ret = register_chrdev_region(dev, VIDEO_NUM_DEVICES, VIDEO_NAME);
1049 	if (ret < 0) {
1050 		pr_warn("videodev: unable to get major %d\n",
1051 				VIDEO_MAJOR);
1052 		return ret;
1053 	}
1054 
1055 	ret = class_register(&video_class);
1056 	if (ret < 0) {
1057 		unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
1058 		pr_warn("video_dev: class_register failed\n");
1059 		return -EIO;
1060 	}
1061 
1062 	return 0;
1063 }
1064 
1065 static void __exit videodev_exit(void)
1066 {
1067 	dev_t dev = MKDEV(VIDEO_MAJOR, 0);
1068 
1069 	class_unregister(&video_class);
1070 	unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
1071 }
1072 
1073 subsys_initcall(videodev_init);
1074 module_exit(videodev_exit)
1075 
1076 MODULE_AUTHOR("Alan Cox, Mauro Carvalho Chehab <mchehab@kernel.org>");
1077 MODULE_DESCRIPTION("Device registrar for Video4Linux drivers v2");
1078 MODULE_LICENSE("GPL");
1079 MODULE_ALIAS_CHARDEV_MAJOR(VIDEO_MAJOR);
1080