1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Video capture interface for Linux version 2
4 *
5 * A generic video device interface for the LINUX operating system
6 * using a set of device structures/vectors for low level operations.
7 *
8 * Authors: Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1)
9 * Mauro Carvalho Chehab <mchehab@kernel.org> (version 2)
10 *
11 * Fixes: 20000516 Claudio Matsuoka <claudio@conectiva.com>
12 * - Added procfs support
13 */
14
15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17#include <linux/debugfs.h>
18#include <linux/module.h>
19#include <linux/types.h>
20#include <linux/kernel.h>
21#include <linux/mm.h>
22#include <linux/string.h>
23#include <linux/errno.h>
24#include <linux/init.h>
25#include <linux/kmod.h>
26#include <linux/slab.h>
27#include <linux/uaccess.h>
28
29#include <media/v4l2-common.h>
30#include <media/v4l2-device.h>
31#include <media/v4l2-ioctl.h>
32#include <media/v4l2-event.h>
33
34#define VIDEO_NUM_DEVICES 256
35#define VIDEO_NAME "video4linux"
36
37#define dprintk(fmt, arg...) do { \
38 printk(KERN_DEBUG pr_fmt("%s: " fmt), \
39 __func__, ##arg); \
40} while (0)
41
42/*
43 * sysfs stuff
44 */
45
46static ssize_t index_show(struct device *cd,
47 struct device_attribute *attr, char *buf)
48{
49 struct video_device *vdev = to_video_device(cd);
50
51 return sprintf(buf, fmt: "%i\n", vdev->index);
52}
53static DEVICE_ATTR_RO(index);
54
55static ssize_t dev_debug_show(struct device *cd,
56 struct device_attribute *attr, char *buf)
57{
58 struct video_device *vdev = to_video_device(cd);
59
60 return sprintf(buf, fmt: "%i\n", vdev->dev_debug);
61}
62
63static ssize_t dev_debug_store(struct device *cd, struct device_attribute *attr,
64 const char *buf, size_t len)
65{
66 struct video_device *vdev = to_video_device(cd);
67 int res = 0;
68 u16 value;
69
70 res = kstrtou16(s: buf, base: 0, res: &value);
71 if (res)
72 return res;
73
74 vdev->dev_debug = value;
75 return len;
76}
77static DEVICE_ATTR_RW(dev_debug);
78
79static ssize_t name_show(struct device *cd,
80 struct device_attribute *attr, char *buf)
81{
82 struct video_device *vdev = to_video_device(cd);
83
84 return sprintf(buf, fmt: "%.*s\n", (int)sizeof(vdev->name), vdev->name);
85}
86static DEVICE_ATTR_RO(name);
87
88static struct attribute *video_device_attrs[] = {
89 &dev_attr_name.attr,
90 &dev_attr_dev_debug.attr,
91 &dev_attr_index.attr,
92 NULL,
93};
94ATTRIBUTE_GROUPS(video_device);
95
96/*
97 * Active devices
98 */
99static struct video_device *video_devices[VIDEO_NUM_DEVICES];
100static DEFINE_MUTEX(videodev_lock);
101static DECLARE_BITMAP(devnode_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES);
102
103/* Device node utility functions */
104
105/* Note: these utility functions all assume that vfl_type is in the range
106 [0, VFL_TYPE_MAX-1]. */
107
108#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
109/* Return the bitmap corresponding to vfl_type. */
110static inline unsigned long *devnode_bits(enum vfl_devnode_type vfl_type)
111{
112 /* Any types not assigned to fixed minor ranges must be mapped to
113 one single bitmap for the purposes of finding a free node number
114 since all those unassigned types use the same minor range. */
115 int idx = (vfl_type > VFL_TYPE_RADIO) ? VFL_TYPE_MAX - 1 : vfl_type;
116
117 return devnode_nums[idx];
118}
119#else
120/* Return the bitmap corresponding to vfl_type. */
121static inline unsigned long *devnode_bits(enum vfl_devnode_type vfl_type)
122{
123 return devnode_nums[vfl_type];
124}
125#endif
126
127/* Mark device node number vdev->num as used */
128static inline void devnode_set(struct video_device *vdev)
129{
130 set_bit(nr: vdev->num, addr: devnode_bits(vfl_type: vdev->vfl_type));
131}
132
133/* Mark device node number vdev->num as unused */
134static inline void devnode_clear(struct video_device *vdev)
135{
136 clear_bit(nr: vdev->num, addr: devnode_bits(vfl_type: vdev->vfl_type));
137}
138
139/* Try to find a free device node number in the range [from, to> */
140static inline int devnode_find(struct video_device *vdev, int from, int to)
141{
142 return find_next_zero_bit(addr: devnode_bits(vfl_type: vdev->vfl_type), size: to, offset: from);
143}
144
145struct video_device *video_device_alloc(void)
146{
147 return kzalloc(size: sizeof(struct video_device), GFP_KERNEL);
148}
149EXPORT_SYMBOL(video_device_alloc);
150
151void video_device_release(struct video_device *vdev)
152{
153 kfree(objp: vdev);
154}
155EXPORT_SYMBOL(video_device_release);
156
157void video_device_release_empty(struct video_device *vdev)
158{
159 /* Do nothing */
160 /* Only valid when the video_device struct is a static. */
161}
162EXPORT_SYMBOL(video_device_release_empty);
163
164static inline void video_get(struct video_device *vdev)
165{
166 get_device(dev: &vdev->dev);
167}
168
169static inline void video_put(struct video_device *vdev)
170{
171 put_device(dev: &vdev->dev);
172}
173
174/* Called when the last user of the video device exits. */
175static void v4l2_device_release(struct device *cd)
176{
177 struct video_device *vdev = to_video_device(cd);
178 struct v4l2_device *v4l2_dev = vdev->v4l2_dev;
179
180 mutex_lock(&videodev_lock);
181 if (WARN_ON(video_devices[vdev->minor] != vdev)) {
182 /* should not happen */
183 mutex_unlock(lock: &videodev_lock);
184 return;
185 }
186
187 /* Free up this device for reuse */
188 video_devices[vdev->minor] = NULL;
189
190 /* Delete the cdev on this minor as well */
191 cdev_del(vdev->cdev);
192 /* Just in case some driver tries to access this from
193 the release() callback. */
194 vdev->cdev = NULL;
195
196 /* Mark device node number as free */
197 devnode_clear(vdev);
198
199 mutex_unlock(lock: &videodev_lock);
200
201#if defined(CONFIG_MEDIA_CONTROLLER)
202 if (v4l2_dev->mdev && vdev->vfl_dir != VFL_DIR_M2M) {
203 /* Remove interfaces and interface links */
204 media_devnode_remove(devnode: vdev->intf_devnode);
205 if (vdev->entity.function != MEDIA_ENT_F_UNKNOWN)
206 media_device_unregister_entity(entity: &vdev->entity);
207 }
208#endif
209
210 /* Do not call v4l2_device_put if there is no release callback set.
211 * Drivers that have no v4l2_device release callback might free the
212 * v4l2_dev instance in the video_device release callback below, so we
213 * must perform this check here.
214 *
215 * TODO: In the long run all drivers that use v4l2_device should use the
216 * v4l2_device release callback. This check will then be unnecessary.
217 */
218 if (v4l2_dev->release == NULL)
219 v4l2_dev = NULL;
220
221 /* Release video_device and perform other
222 cleanups as needed. */
223 vdev->release(vdev);
224
225 /* Decrease v4l2_device refcount */
226 if (v4l2_dev)
227 v4l2_device_put(v4l2_dev);
228}
229
230static struct class video_class = {
231 .name = VIDEO_NAME,
232 .dev_groups = video_device_groups,
233};
234
235struct video_device *video_devdata(struct file *file)
236{
237 return video_devices[iminor(inode: file_inode(f: file))];
238}
239EXPORT_SYMBOL(video_devdata);
240
241
242/* Priority handling */
243
244static inline bool prio_is_valid(enum v4l2_priority prio)
245{
246 return prio == V4L2_PRIORITY_BACKGROUND ||
247 prio == V4L2_PRIORITY_INTERACTIVE ||
248 prio == V4L2_PRIORITY_RECORD;
249}
250
251void v4l2_prio_init(struct v4l2_prio_state *global)
252{
253 memset(global, 0, sizeof(*global));
254}
255EXPORT_SYMBOL(v4l2_prio_init);
256
257int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
258 enum v4l2_priority new)
259{
260 if (!prio_is_valid(prio: new))
261 return -EINVAL;
262 if (*local == new)
263 return 0;
264
265 atomic_inc(v: &global->prios[new]);
266 if (prio_is_valid(prio: *local))
267 atomic_dec(v: &global->prios[*local]);
268 *local = new;
269 return 0;
270}
271EXPORT_SYMBOL(v4l2_prio_change);
272
273void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local)
274{
275 v4l2_prio_change(global, local, V4L2_PRIORITY_DEFAULT);
276}
277EXPORT_SYMBOL(v4l2_prio_open);
278
279void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local)
280{
281 if (prio_is_valid(prio: local))
282 atomic_dec(v: &global->prios[local]);
283}
284EXPORT_SYMBOL(v4l2_prio_close);
285
286enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global)
287{
288 if (atomic_read(v: &global->prios[V4L2_PRIORITY_RECORD]) > 0)
289 return V4L2_PRIORITY_RECORD;
290 if (atomic_read(v: &global->prios[V4L2_PRIORITY_INTERACTIVE]) > 0)
291 return V4L2_PRIORITY_INTERACTIVE;
292 if (atomic_read(v: &global->prios[V4L2_PRIORITY_BACKGROUND]) > 0)
293 return V4L2_PRIORITY_BACKGROUND;
294 return V4L2_PRIORITY_UNSET;
295}
296EXPORT_SYMBOL(v4l2_prio_max);
297
298int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local)
299{
300 return (local < v4l2_prio_max(global)) ? -EBUSY : 0;
301}
302EXPORT_SYMBOL(v4l2_prio_check);
303
304
305static ssize_t v4l2_read(struct file *filp, char __user *buf,
306 size_t sz, loff_t *off)
307{
308 struct video_device *vdev = video_devdata(filp);
309 int ret = -ENODEV;
310
311 if (!vdev->fops->read)
312 return -EINVAL;
313 if (video_is_registered(vdev))
314 ret = vdev->fops->read(filp, buf, sz, off);
315 if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
316 (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
317 dprintk("%s: read: %zd (%d)\n",
318 video_device_node_name(vdev), sz, ret);
319 return ret;
320}
321
322static ssize_t v4l2_write(struct file *filp, const char __user *buf,
323 size_t sz, loff_t *off)
324{
325 struct video_device *vdev = video_devdata(filp);
326 int ret = -ENODEV;
327
328 if (!vdev->fops->write)
329 return -EINVAL;
330 if (video_is_registered(vdev))
331 ret = vdev->fops->write(filp, buf, sz, off);
332 if ((vdev->dev_debug & V4L2_DEV_DEBUG_FOP) &&
333 (vdev->dev_debug & V4L2_DEV_DEBUG_STREAMING))
334 dprintk("%s: write: %zd (%d)\n",
335 video_device_node_name(vdev), sz, ret);
336 return ret;
337}
338
339static __poll_t v4l2_poll(struct file *filp, struct poll_table_struct *poll)
340{
341 struct video_device *vdev = video_devdata(filp);
342 __poll_t res = EPOLLERR | EPOLLHUP | EPOLLPRI;
343
344 if (video_is_registered(vdev)) {
345 if (!vdev->fops->poll)
346 res = DEFAULT_POLLMASK;
347 else
348 res = vdev->fops->poll(filp, poll);
349 }
350 if (vdev->dev_debug & V4L2_DEV_DEBUG_POLL)
351 dprintk("%s: poll: %08x %08x\n",
352 video_device_node_name(vdev), res,
353 poll_requested_events(poll));
354 return res;
355}
356
357static 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
374static 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
393static 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 */
409static 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(lock: &videodev_lock);
420 return -ENODEV;
421 }
422 /* and increase the device refcount */
423 video_get(vdev);
424 mutex_unlock(lock: &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 */
442static int v4l2_release(struct inode *inode, struct file *filp)
443{
444 struct video_device *vdev = video_devdata(filp);
445 int ret = 0;
446
447 /*
448 * We need to serialize the release() with queueing new requests.
449 * The release() may trigger the cancellation of a streaming
450 * operation, and that should not be mixed with queueing a new
451 * request at the same time.
452 */
453 if (vdev->fops->release) {
454 if (v4l2_device_supports_requests(v4l2_dev: vdev->v4l2_dev)) {
455 mutex_lock(&vdev->v4l2_dev->mdev->req_queue_mutex);
456 ret = vdev->fops->release(filp);
457 mutex_unlock(lock: &vdev->v4l2_dev->mdev->req_queue_mutex);
458 } else {
459 ret = vdev->fops->release(filp);
460 }
461 }
462
463 if (vdev->dev_debug & V4L2_DEV_DEBUG_FOP)
464 dprintk("%s: release\n",
465 video_device_node_name(vdev));
466
467 /* decrease the refcount unconditionally since the release()
468 return value is ignored. */
469 video_put(vdev);
470 return ret;
471}
472
473static const struct file_operations v4l2_fops = {
474 .owner = THIS_MODULE,
475 .read = v4l2_read,
476 .write = v4l2_write,
477 .open = v4l2_open,
478 .get_unmapped_area = v4l2_get_unmapped_area,
479 .mmap = v4l2_mmap,
480 .unlocked_ioctl = v4l2_ioctl,
481#ifdef CONFIG_COMPAT
482 .compat_ioctl = v4l2_compat_ioctl32,
483#endif
484 .release = v4l2_release,
485 .poll = v4l2_poll,
486 .llseek = no_llseek,
487};
488
489/**
490 * get_index - assign stream index number based on v4l2_dev
491 * @vdev: video_device to assign index number to, vdev->v4l2_dev should be assigned
492 *
493 * Note that when this is called the new device has not yet been registered
494 * in the video_device array, but it was able to obtain a minor number.
495 *
496 * This means that we can always obtain a free stream index number since
497 * the worst case scenario is that there are VIDEO_NUM_DEVICES - 1 slots in
498 * use of the video_device array.
499 *
500 * Returns a free index number.
501 */
502static int get_index(struct video_device *vdev)
503{
504 /* This can be static since this function is called with the global
505 videodev_lock held. */
506 static DECLARE_BITMAP(used, VIDEO_NUM_DEVICES);
507 int i;
508
509 bitmap_zero(dst: used, VIDEO_NUM_DEVICES);
510
511 for (i = 0; i < VIDEO_NUM_DEVICES; i++) {
512 if (video_devices[i] != NULL &&
513 video_devices[i]->v4l2_dev == vdev->v4l2_dev) {
514 __set_bit(video_devices[i]->index, used);
515 }
516 }
517
518 return find_first_zero_bit(addr: used, VIDEO_NUM_DEVICES);
519}
520
521#define SET_VALID_IOCTL(ops, cmd, op) \
522 do { if ((ops)->op) __set_bit(_IOC_NR(cmd), valid_ioctls); } while (0)
523
524/* This determines which ioctls are actually implemented in the driver.
525 It's a one-time thing which simplifies video_ioctl2 as it can just do
526 a bit test.
527
528 Note that drivers can override this by setting bits to 1 in
529 vdev->valid_ioctls. If an ioctl is marked as 1 when this function is
530 called, then that ioctl will actually be marked as unimplemented.
531
532 It does that by first setting up the local valid_ioctls bitmap, and
533 at the end do a:
534
535 vdev->valid_ioctls = valid_ioctls & ~(vdev->valid_ioctls)
536 */
537static void determine_valid_ioctls(struct video_device *vdev)
538{
539 const u32 vid_caps = V4L2_CAP_VIDEO_CAPTURE |
540 V4L2_CAP_VIDEO_CAPTURE_MPLANE |
541 V4L2_CAP_VIDEO_OUTPUT |
542 V4L2_CAP_VIDEO_OUTPUT_MPLANE |
543 V4L2_CAP_VIDEO_M2M | V4L2_CAP_VIDEO_M2M_MPLANE;
544 const u32 meta_caps = V4L2_CAP_META_CAPTURE |
545 V4L2_CAP_META_OUTPUT;
546 DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE);
547 const struct v4l2_ioctl_ops *ops = vdev->ioctl_ops;
548 bool is_vid = vdev->vfl_type == VFL_TYPE_VIDEO &&
549 (vdev->device_caps & vid_caps);
550 bool is_vbi = vdev->vfl_type == VFL_TYPE_VBI;
551 bool is_radio = vdev->vfl_type == VFL_TYPE_RADIO;
552 bool is_sdr = vdev->vfl_type == VFL_TYPE_SDR;
553 bool is_tch = vdev->vfl_type == VFL_TYPE_TOUCH;
554 bool is_meta = vdev->vfl_type == VFL_TYPE_VIDEO &&
555 (vdev->device_caps & meta_caps);
556 bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
557 bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
558 bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
559 bool has_streaming = vdev->device_caps & V4L2_CAP_STREAMING;
560
561 bitmap_zero(dst: valid_ioctls, BASE_VIDIOC_PRIVATE);
562
563 /* vfl_type and vfl_dir independent ioctls */
564
565 SET_VALID_IOCTL(ops, VIDIOC_QUERYCAP, vidioc_querycap);
566 __set_bit(_IOC_NR(VIDIOC_G_PRIORITY), valid_ioctls);
567 __set_bit(_IOC_NR(VIDIOC_S_PRIORITY), valid_ioctls);
568
569 /* Note: the control handler can also be passed through the filehandle,
570 and that can't be tested here. If the bit for these control ioctls
571 is set, then the ioctl is valid. But if it is 0, then it can still
572 be valid if the filehandle passed the control handler. */
573 if (vdev->ctrl_handler || ops->vidioc_queryctrl)
574 __set_bit(_IOC_NR(VIDIOC_QUERYCTRL), valid_ioctls);
575 if (vdev->ctrl_handler || ops->vidioc_query_ext_ctrl)
576 __set_bit(_IOC_NR(VIDIOC_QUERY_EXT_CTRL), valid_ioctls);
577 if (vdev->ctrl_handler || ops->vidioc_g_ctrl || ops->vidioc_g_ext_ctrls)
578 __set_bit(_IOC_NR(VIDIOC_G_CTRL), valid_ioctls);
579 if (vdev->ctrl_handler || ops->vidioc_s_ctrl || ops->vidioc_s_ext_ctrls)
580 __set_bit(_IOC_NR(VIDIOC_S_CTRL), valid_ioctls);
581 if (vdev->ctrl_handler || ops->vidioc_g_ext_ctrls)
582 __set_bit(_IOC_NR(VIDIOC_G_EXT_CTRLS), valid_ioctls);
583 if (vdev->ctrl_handler || ops->vidioc_s_ext_ctrls)
584 __set_bit(_IOC_NR(VIDIOC_S_EXT_CTRLS), valid_ioctls);
585 if (vdev->ctrl_handler || ops->vidioc_try_ext_ctrls)
586 __set_bit(_IOC_NR(VIDIOC_TRY_EXT_CTRLS), valid_ioctls);
587 if (vdev->ctrl_handler || ops->vidioc_querymenu)
588 __set_bit(_IOC_NR(VIDIOC_QUERYMENU), valid_ioctls);
589 if (!is_tch) {
590 SET_VALID_IOCTL(ops, VIDIOC_G_FREQUENCY, vidioc_g_frequency);
591 SET_VALID_IOCTL(ops, VIDIOC_S_FREQUENCY, vidioc_s_frequency);
592 }
593 SET_VALID_IOCTL(ops, VIDIOC_LOG_STATUS, vidioc_log_status);
594#ifdef CONFIG_VIDEO_ADV_DEBUG
595 __set_bit(_IOC_NR(VIDIOC_DBG_G_CHIP_INFO), valid_ioctls);
596 __set_bit(_IOC_NR(VIDIOC_DBG_G_REGISTER), valid_ioctls);
597 __set_bit(_IOC_NR(VIDIOC_DBG_S_REGISTER), valid_ioctls);
598#endif
599 /* yes, really vidioc_subscribe_event */
600 SET_VALID_IOCTL(ops, VIDIOC_DQEVENT, vidioc_subscribe_event);
601 SET_VALID_IOCTL(ops, VIDIOC_SUBSCRIBE_EVENT, vidioc_subscribe_event);
602 SET_VALID_IOCTL(ops, VIDIOC_UNSUBSCRIBE_EVENT, vidioc_unsubscribe_event);
603 if (ops->vidioc_enum_freq_bands || ops->vidioc_g_tuner || ops->vidioc_g_modulator)
604 __set_bit(_IOC_NR(VIDIOC_ENUM_FREQ_BANDS), valid_ioctls);
605
606 if (is_vid) {
607 /* video specific ioctls */
608 if ((is_rx && (ops->vidioc_enum_fmt_vid_cap ||
609 ops->vidioc_enum_fmt_vid_overlay)) ||
610 (is_tx && ops->vidioc_enum_fmt_vid_out))
611 __set_bit(_IOC_NR(VIDIOC_ENUM_FMT), valid_ioctls);
612 if ((is_rx && (ops->vidioc_g_fmt_vid_cap ||
613 ops->vidioc_g_fmt_vid_cap_mplane ||
614 ops->vidioc_g_fmt_vid_overlay)) ||
615 (is_tx && (ops->vidioc_g_fmt_vid_out ||
616 ops->vidioc_g_fmt_vid_out_mplane ||
617 ops->vidioc_g_fmt_vid_out_overlay)))
618 __set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
619 if ((is_rx && (ops->vidioc_s_fmt_vid_cap ||
620 ops->vidioc_s_fmt_vid_cap_mplane ||
621 ops->vidioc_s_fmt_vid_overlay)) ||
622 (is_tx && (ops->vidioc_s_fmt_vid_out ||
623 ops->vidioc_s_fmt_vid_out_mplane ||
624 ops->vidioc_s_fmt_vid_out_overlay)))
625 __set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
626 if ((is_rx && (ops->vidioc_try_fmt_vid_cap ||
627 ops->vidioc_try_fmt_vid_cap_mplane ||
628 ops->vidioc_try_fmt_vid_overlay)) ||
629 (is_tx && (ops->vidioc_try_fmt_vid_out ||
630 ops->vidioc_try_fmt_vid_out_mplane ||
631 ops->vidioc_try_fmt_vid_out_overlay)))
632 __set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
633 SET_VALID_IOCTL(ops, VIDIOC_OVERLAY, vidioc_overlay);
634 SET_VALID_IOCTL(ops, VIDIOC_G_FBUF, vidioc_g_fbuf);
635 SET_VALID_IOCTL(ops, VIDIOC_S_FBUF, vidioc_s_fbuf);
636 SET_VALID_IOCTL(ops, VIDIOC_G_JPEGCOMP, vidioc_g_jpegcomp);
637 SET_VALID_IOCTL(ops, VIDIOC_S_JPEGCOMP, vidioc_s_jpegcomp);
638 SET_VALID_IOCTL(ops, VIDIOC_G_ENC_INDEX, vidioc_g_enc_index);
639 SET_VALID_IOCTL(ops, VIDIOC_ENCODER_CMD, vidioc_encoder_cmd);
640 SET_VALID_IOCTL(ops, VIDIOC_TRY_ENCODER_CMD, vidioc_try_encoder_cmd);
641 SET_VALID_IOCTL(ops, VIDIOC_DECODER_CMD, vidioc_decoder_cmd);
642 SET_VALID_IOCTL(ops, VIDIOC_TRY_DECODER_CMD, vidioc_try_decoder_cmd);
643 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FRAMESIZES, vidioc_enum_framesizes);
644 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FRAMEINTERVALS, vidioc_enum_frameintervals);
645 if (ops->vidioc_g_selection &&
646 !test_bit(_IOC_NR(VIDIOC_G_SELECTION), vdev->valid_ioctls)) {
647 __set_bit(_IOC_NR(VIDIOC_G_CROP), valid_ioctls);
648 __set_bit(_IOC_NR(VIDIOC_CROPCAP), valid_ioctls);
649 }
650 if (ops->vidioc_s_selection &&
651 !test_bit(_IOC_NR(VIDIOC_S_SELECTION), vdev->valid_ioctls))
652 __set_bit(_IOC_NR(VIDIOC_S_CROP), valid_ioctls);
653 SET_VALID_IOCTL(ops, VIDIOC_G_SELECTION, vidioc_g_selection);
654 SET_VALID_IOCTL(ops, VIDIOC_S_SELECTION, vidioc_s_selection);
655 }
656 if (is_meta && is_rx) {
657 /* metadata capture specific ioctls */
658 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FMT, vidioc_enum_fmt_meta_cap);
659 SET_VALID_IOCTL(ops, VIDIOC_G_FMT, vidioc_g_fmt_meta_cap);
660 SET_VALID_IOCTL(ops, VIDIOC_S_FMT, vidioc_s_fmt_meta_cap);
661 SET_VALID_IOCTL(ops, VIDIOC_TRY_FMT, vidioc_try_fmt_meta_cap);
662 } else if (is_meta && is_tx) {
663 /* metadata output specific ioctls */
664 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FMT, vidioc_enum_fmt_meta_out);
665 SET_VALID_IOCTL(ops, VIDIOC_G_FMT, vidioc_g_fmt_meta_out);
666 SET_VALID_IOCTL(ops, VIDIOC_S_FMT, vidioc_s_fmt_meta_out);
667 SET_VALID_IOCTL(ops, VIDIOC_TRY_FMT, vidioc_try_fmt_meta_out);
668 }
669 if (is_vbi) {
670 /* vbi specific ioctls */
671 if ((is_rx && (ops->vidioc_g_fmt_vbi_cap ||
672 ops->vidioc_g_fmt_sliced_vbi_cap)) ||
673 (is_tx && (ops->vidioc_g_fmt_vbi_out ||
674 ops->vidioc_g_fmt_sliced_vbi_out)))
675 __set_bit(_IOC_NR(VIDIOC_G_FMT), valid_ioctls);
676 if ((is_rx && (ops->vidioc_s_fmt_vbi_cap ||
677 ops->vidioc_s_fmt_sliced_vbi_cap)) ||
678 (is_tx && (ops->vidioc_s_fmt_vbi_out ||
679 ops->vidioc_s_fmt_sliced_vbi_out)))
680 __set_bit(_IOC_NR(VIDIOC_S_FMT), valid_ioctls);
681 if ((is_rx && (ops->vidioc_try_fmt_vbi_cap ||
682 ops->vidioc_try_fmt_sliced_vbi_cap)) ||
683 (is_tx && (ops->vidioc_try_fmt_vbi_out ||
684 ops->vidioc_try_fmt_sliced_vbi_out)))
685 __set_bit(_IOC_NR(VIDIOC_TRY_FMT), valid_ioctls);
686 SET_VALID_IOCTL(ops, VIDIOC_G_SLICED_VBI_CAP, vidioc_g_sliced_vbi_cap);
687 } else if (is_tch) {
688 /* touch specific ioctls */
689 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FMT, vidioc_enum_fmt_vid_cap);
690 SET_VALID_IOCTL(ops, VIDIOC_G_FMT, vidioc_g_fmt_vid_cap);
691 SET_VALID_IOCTL(ops, VIDIOC_S_FMT, vidioc_s_fmt_vid_cap);
692 SET_VALID_IOCTL(ops, VIDIOC_TRY_FMT, vidioc_try_fmt_vid_cap);
693 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FRAMESIZES, vidioc_enum_framesizes);
694 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FRAMEINTERVALS, vidioc_enum_frameintervals);
695 SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
696 SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
697 SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
698 SET_VALID_IOCTL(ops, VIDIOC_G_PARM, vidioc_g_parm);
699 SET_VALID_IOCTL(ops, VIDIOC_S_PARM, vidioc_s_parm);
700 } else if (is_sdr && is_rx) {
701 /* SDR receiver specific ioctls */
702 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FMT, vidioc_enum_fmt_sdr_cap);
703 SET_VALID_IOCTL(ops, VIDIOC_G_FMT, vidioc_g_fmt_sdr_cap);
704 SET_VALID_IOCTL(ops, VIDIOC_S_FMT, vidioc_s_fmt_sdr_cap);
705 SET_VALID_IOCTL(ops, VIDIOC_TRY_FMT, vidioc_try_fmt_sdr_cap);
706 } else if (is_sdr && is_tx) {
707 /* SDR transmitter specific ioctls */
708 SET_VALID_IOCTL(ops, VIDIOC_ENUM_FMT, vidioc_enum_fmt_sdr_out);
709 SET_VALID_IOCTL(ops, VIDIOC_G_FMT, vidioc_g_fmt_sdr_out);
710 SET_VALID_IOCTL(ops, VIDIOC_S_FMT, vidioc_s_fmt_sdr_out);
711 SET_VALID_IOCTL(ops, VIDIOC_TRY_FMT, vidioc_try_fmt_sdr_out);
712 }
713
714 if (has_streaming) {
715 /* ioctls valid for streaming I/O */
716 SET_VALID_IOCTL(ops, VIDIOC_REQBUFS, vidioc_reqbufs);
717 SET_VALID_IOCTL(ops, VIDIOC_QUERYBUF, vidioc_querybuf);
718 SET_VALID_IOCTL(ops, VIDIOC_QBUF, vidioc_qbuf);
719 SET_VALID_IOCTL(ops, VIDIOC_EXPBUF, vidioc_expbuf);
720 SET_VALID_IOCTL(ops, VIDIOC_DQBUF, vidioc_dqbuf);
721 SET_VALID_IOCTL(ops, VIDIOC_CREATE_BUFS, vidioc_create_bufs);
722 SET_VALID_IOCTL(ops, VIDIOC_PREPARE_BUF, vidioc_prepare_buf);
723 SET_VALID_IOCTL(ops, VIDIOC_STREAMON, vidioc_streamon);
724 SET_VALID_IOCTL(ops, VIDIOC_STREAMOFF, vidioc_streamoff);
725 }
726
727 if (is_vid || is_vbi || is_meta) {
728 /* ioctls valid for video, vbi and metadata */
729 if (ops->vidioc_s_std)
730 __set_bit(_IOC_NR(VIDIOC_ENUMSTD), valid_ioctls);
731 SET_VALID_IOCTL(ops, VIDIOC_S_STD, vidioc_s_std);
732 SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
733 if (is_rx) {
734 SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
735 if (is_io_mc) {
736 __set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
737 __set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
738 __set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
739 } else {
740 SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
741 SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
742 SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
743 }
744 SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
745 SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
746 SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
747 SET_VALID_IOCTL(ops, VIDIOC_QUERY_DV_TIMINGS, vidioc_query_dv_timings);
748 SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
749 }
750 if (is_tx) {
751 if (is_io_mc) {
752 __set_bit(_IOC_NR(VIDIOC_ENUMOUTPUT), valid_ioctls);
753 __set_bit(_IOC_NR(VIDIOC_G_OUTPUT), valid_ioctls);
754 __set_bit(_IOC_NR(VIDIOC_S_OUTPUT), valid_ioctls);
755 } else {
756 SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
757 SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
758 SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
759 }
760 SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
761 SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
762 SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
763 }
764 if (ops->vidioc_g_parm || ops->vidioc_g_std)
765 __set_bit(_IOC_NR(VIDIOC_G_PARM), valid_ioctls);
766 SET_VALID_IOCTL(ops, VIDIOC_S_PARM, vidioc_s_parm);
767 SET_VALID_IOCTL(ops, VIDIOC_S_DV_TIMINGS, vidioc_s_dv_timings);
768 SET_VALID_IOCTL(ops, VIDIOC_G_DV_TIMINGS, vidioc_g_dv_timings);
769 SET_VALID_IOCTL(ops, VIDIOC_ENUM_DV_TIMINGS, vidioc_enum_dv_timings);
770 SET_VALID_IOCTL(ops, VIDIOC_DV_TIMINGS_CAP, vidioc_dv_timings_cap);
771 SET_VALID_IOCTL(ops, VIDIOC_G_EDID, vidioc_g_edid);
772 }
773 if (is_tx && (is_radio || is_sdr)) {
774 /* radio transmitter only ioctls */
775 SET_VALID_IOCTL(ops, VIDIOC_G_MODULATOR, vidioc_g_modulator);
776 SET_VALID_IOCTL(ops, VIDIOC_S_MODULATOR, vidioc_s_modulator);
777 }
778 if (is_rx && !is_tch) {
779 /* receiver only ioctls */
780 SET_VALID_IOCTL(ops, VIDIOC_G_TUNER, vidioc_g_tuner);
781 SET_VALID_IOCTL(ops, VIDIOC_S_TUNER, vidioc_s_tuner);
782 SET_VALID_IOCTL(ops, VIDIOC_S_HW_FREQ_SEEK, vidioc_s_hw_freq_seek);
783 }
784
785 bitmap_andnot(dst: vdev->valid_ioctls, src1: valid_ioctls, src2: vdev->valid_ioctls,
786 BASE_VIDIOC_PRIVATE);
787}
788
789static int video_register_media_controller(struct video_device *vdev)
790{
791#if defined(CONFIG_MEDIA_CONTROLLER)
792 u32 intf_type;
793 int ret;
794
795 /* Memory-to-memory devices are more complex and use
796 * their own function to register its mc entities.
797 */
798 if (!vdev->v4l2_dev->mdev || vdev->vfl_dir == VFL_DIR_M2M)
799 return 0;
800
801 vdev->entity.obj_type = MEDIA_ENTITY_TYPE_VIDEO_DEVICE;
802 vdev->entity.function = MEDIA_ENT_F_UNKNOWN;
803
804 switch (vdev->vfl_type) {
805 case VFL_TYPE_VIDEO:
806 intf_type = MEDIA_INTF_T_V4L_VIDEO;
807 vdev->entity.function = MEDIA_ENT_F_IO_V4L;
808 break;
809 case VFL_TYPE_VBI:
810 intf_type = MEDIA_INTF_T_V4L_VBI;
811 vdev->entity.function = MEDIA_ENT_F_IO_VBI;
812 break;
813 case VFL_TYPE_SDR:
814 intf_type = MEDIA_INTF_T_V4L_SWRADIO;
815 vdev->entity.function = MEDIA_ENT_F_IO_SWRADIO;
816 break;
817 case VFL_TYPE_TOUCH:
818 intf_type = MEDIA_INTF_T_V4L_TOUCH;
819 vdev->entity.function = MEDIA_ENT_F_IO_V4L;
820 break;
821 case VFL_TYPE_RADIO:
822 intf_type = MEDIA_INTF_T_V4L_RADIO;
823 /*
824 * Radio doesn't have an entity at the V4L2 side to represent
825 * radio input or output. Instead, the audio input/output goes
826 * via either physical wires or ALSA.
827 */
828 break;
829 case VFL_TYPE_SUBDEV:
830 intf_type = MEDIA_INTF_T_V4L_SUBDEV;
831 /* Entity will be created via v4l2_device_register_subdev() */
832 break;
833 default:
834 return 0;
835 }
836
837 if (vdev->entity.function != MEDIA_ENT_F_UNKNOWN) {
838 vdev->entity.name = vdev->name;
839
840 /* Needed just for backward compatibility with legacy MC API */
841 vdev->entity.info.dev.major = VIDEO_MAJOR;
842 vdev->entity.info.dev.minor = vdev->minor;
843
844 ret = media_device_register_entity(mdev: vdev->v4l2_dev->mdev,
845 entity: &vdev->entity);
846 if (ret < 0) {
847 pr_warn("%s: media_device_register_entity failed\n",
848 __func__);
849 return ret;
850 }
851 }
852
853 vdev->intf_devnode = media_devnode_create(mdev: vdev->v4l2_dev->mdev,
854 type: intf_type,
855 flags: 0, VIDEO_MAJOR,
856 minor: vdev->minor);
857 if (!vdev->intf_devnode) {
858 media_device_unregister_entity(entity: &vdev->entity);
859 return -ENOMEM;
860 }
861
862 if (vdev->entity.function != MEDIA_ENT_F_UNKNOWN) {
863 struct media_link *link;
864
865 link = media_create_intf_link(entity: &vdev->entity,
866 intf: &vdev->intf_devnode->intf,
867 MEDIA_LNK_FL_ENABLED |
868 MEDIA_LNK_FL_IMMUTABLE);
869 if (!link) {
870 media_devnode_remove(devnode: vdev->intf_devnode);
871 media_device_unregister_entity(entity: &vdev->entity);
872 return -ENOMEM;
873 }
874 }
875
876 /* FIXME: how to create the other interface links? */
877
878#endif
879 return 0;
880}
881
882int __video_register_device(struct video_device *vdev,
883 enum vfl_devnode_type type,
884 int nr, int warn_if_nr_in_use,
885 struct module *owner)
886{
887 int i = 0;
888 int ret;
889 int minor_offset = 0;
890 int minor_cnt = VIDEO_NUM_DEVICES;
891 const char *name_base;
892
893 /* A minor value of -1 marks this video device as never
894 having been registered */
895 vdev->minor = -1;
896
897 /* the release callback MUST be present */
898 if (WARN_ON(!vdev->release))
899 return -EINVAL;
900 /* the v4l2_dev pointer MUST be present */
901 if (WARN_ON(!vdev->v4l2_dev))
902 return -EINVAL;
903 /* the device_caps field MUST be set for all but subdevs */
904 if (WARN_ON(type != VFL_TYPE_SUBDEV && !vdev->device_caps))
905 return -EINVAL;
906
907 /* v4l2_fh support */
908 spin_lock_init(&vdev->fh_lock);
909 INIT_LIST_HEAD(list: &vdev->fh_list);
910
911 /* Part 1: check device type */
912 switch (type) {
913 case VFL_TYPE_VIDEO:
914 name_base = "video";
915 break;
916 case VFL_TYPE_VBI:
917 name_base = "vbi";
918 break;
919 case VFL_TYPE_RADIO:
920 name_base = "radio";
921 break;
922 case VFL_TYPE_SUBDEV:
923 name_base = "v4l-subdev";
924 break;
925 case VFL_TYPE_SDR:
926 /* Use device name 'swradio' because 'sdr' was already taken. */
927 name_base = "swradio";
928 break;
929 case VFL_TYPE_TOUCH:
930 name_base = "v4l-touch";
931 break;
932 default:
933 pr_err("%s called with unknown type: %d\n",
934 __func__, type);
935 return -EINVAL;
936 }
937
938 vdev->vfl_type = type;
939 vdev->cdev = NULL;
940 if (vdev->dev_parent == NULL)
941 vdev->dev_parent = vdev->v4l2_dev->dev;
942 if (vdev->ctrl_handler == NULL)
943 vdev->ctrl_handler = vdev->v4l2_dev->ctrl_handler;
944 /* If the prio state pointer is NULL, then use the v4l2_device
945 prio state. */
946 if (vdev->prio == NULL)
947 vdev->prio = &vdev->v4l2_dev->prio;
948
949 /* Part 2: find a free minor, device node number and device index. */
950#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
951 /* Keep the ranges for the first four types for historical
952 * reasons.
953 * Newer devices (not yet in place) should use the range
954 * of 128-191 and just pick the first free minor there
955 * (new style). */
956 switch (type) {
957 case VFL_TYPE_VIDEO:
958 minor_offset = 0;
959 minor_cnt = 64;
960 break;
961 case VFL_TYPE_RADIO:
962 minor_offset = 64;
963 minor_cnt = 64;
964 break;
965 case VFL_TYPE_VBI:
966 minor_offset = 224;
967 minor_cnt = 32;
968 break;
969 default:
970 minor_offset = 128;
971 minor_cnt = 64;
972 break;
973 }
974#endif
975
976 /* Pick a device node number */
977 mutex_lock(&videodev_lock);
978 nr = devnode_find(vdev, from: nr == -1 ? 0 : nr, to: minor_cnt);
979 if (nr == minor_cnt)
980 nr = devnode_find(vdev, from: 0, to: minor_cnt);
981 if (nr == minor_cnt) {
982 pr_err("could not get a free device node number\n");
983 mutex_unlock(lock: &videodev_lock);
984 return -ENFILE;
985 }
986#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
987 /* 1-on-1 mapping of device node number to minor number */
988 i = nr;
989#else
990 /* The device node number and minor numbers are independent, so
991 we just find the first free minor number. */
992 for (i = 0; i < VIDEO_NUM_DEVICES; i++)
993 if (video_devices[i] == NULL)
994 break;
995 if (i == VIDEO_NUM_DEVICES) {
996 mutex_unlock(&videodev_lock);
997 pr_err("could not get a free minor\n");
998 return -ENFILE;
999 }
1000#endif
1001 vdev->minor = i + minor_offset;
1002 vdev->num = nr;
1003
1004 /* Should not happen since we thought this minor was free */
1005 if (WARN_ON(video_devices[vdev->minor])) {
1006 mutex_unlock(lock: &videodev_lock);
1007 pr_err("video_device not empty!\n");
1008 return -ENFILE;
1009 }
1010 devnode_set(vdev);
1011 vdev->index = get_index(vdev);
1012 video_devices[vdev->minor] = vdev;
1013 mutex_unlock(lock: &videodev_lock);
1014
1015 if (vdev->ioctl_ops)
1016 determine_valid_ioctls(vdev);
1017
1018 /* Part 3: Initialize the character device */
1019 vdev->cdev = cdev_alloc();
1020 if (vdev->cdev == NULL) {
1021 ret = -ENOMEM;
1022 goto cleanup;
1023 }
1024 vdev->cdev->ops = &v4l2_fops;
1025 vdev->cdev->owner = owner;
1026 ret = cdev_add(vdev->cdev, MKDEV(VIDEO_MAJOR, vdev->minor), 1);
1027 if (ret < 0) {
1028 pr_err("%s: cdev_add failed\n", __func__);
1029 kfree(objp: vdev->cdev);
1030 vdev->cdev = NULL;
1031 goto cleanup;
1032 }
1033
1034 /* Part 4: register the device with sysfs */
1035 vdev->dev.class = &video_class;
1036 vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor);
1037 vdev->dev.parent = vdev->dev_parent;
1038 dev_set_name(dev: &vdev->dev, name: "%s%d", name_base, vdev->num);
1039 ret = device_register(dev: &vdev->dev);
1040 if (ret < 0) {
1041 pr_err("%s: device_register failed\n", __func__);
1042 goto cleanup;
1043 }
1044 /* Register the release callback that will be called when the last
1045 reference to the device goes away. */
1046 vdev->dev.release = v4l2_device_release;
1047
1048 if (nr != -1 && nr != vdev->num && warn_if_nr_in_use)
1049 pr_warn("%s: requested %s%d, got %s\n", __func__,
1050 name_base, nr, video_device_node_name(vdev));
1051
1052 /* Increase v4l2_device refcount */
1053 v4l2_device_get(v4l2_dev: vdev->v4l2_dev);
1054
1055 /* Part 5: Register the entity. */
1056 ret = video_register_media_controller(vdev);
1057
1058 /* Part 6: Activate this minor. The char device can now be used. */
1059 set_bit(nr: V4L2_FL_REGISTERED, addr: &vdev->flags);
1060
1061 return 0;
1062
1063cleanup:
1064 mutex_lock(&videodev_lock);
1065 if (vdev->cdev)
1066 cdev_del(vdev->cdev);
1067 video_devices[vdev->minor] = NULL;
1068 devnode_clear(vdev);
1069 mutex_unlock(lock: &videodev_lock);
1070 /* Mark this video device as never having been registered. */
1071 vdev->minor = -1;
1072 return ret;
1073}
1074EXPORT_SYMBOL(__video_register_device);
1075
1076/**
1077 * video_unregister_device - unregister a video4linux device
1078 * @vdev: the device to unregister
1079 *
1080 * This unregisters the passed device. Future open calls will
1081 * be met with errors.
1082 */
1083void video_unregister_device(struct video_device *vdev)
1084{
1085 /* Check if vdev was ever registered at all */
1086 if (!vdev || !video_is_registered(vdev))
1087 return;
1088
1089 mutex_lock(&videodev_lock);
1090 /* This must be in a critical section to prevent a race with v4l2_open.
1091 * Once this bit has been cleared video_get may never be called again.
1092 */
1093 clear_bit(nr: V4L2_FL_REGISTERED, addr: &vdev->flags);
1094 mutex_unlock(lock: &videodev_lock);
1095 if (test_bit(V4L2_FL_USES_V4L2_FH, &vdev->flags))
1096 v4l2_event_wake_all(vdev);
1097 device_unregister(dev: &vdev->dev);
1098}
1099EXPORT_SYMBOL(video_unregister_device);
1100
1101#if defined(CONFIG_MEDIA_CONTROLLER)
1102
1103__must_check int video_device_pipeline_start(struct video_device *vdev,
1104 struct media_pipeline *pipe)
1105{
1106 struct media_entity *entity = &vdev->entity;
1107
1108 if (entity->num_pads != 1)
1109 return -ENODEV;
1110
1111 return media_pipeline_start(pad: &entity->pads[0], pipe);
1112}
1113EXPORT_SYMBOL_GPL(video_device_pipeline_start);
1114
1115__must_check int __video_device_pipeline_start(struct video_device *vdev,
1116 struct media_pipeline *pipe)
1117{
1118 struct media_entity *entity = &vdev->entity;
1119
1120 if (entity->num_pads != 1)
1121 return -ENODEV;
1122
1123 return __media_pipeline_start(pad: &entity->pads[0], pipe);
1124}
1125EXPORT_SYMBOL_GPL(__video_device_pipeline_start);
1126
1127void video_device_pipeline_stop(struct video_device *vdev)
1128{
1129 struct media_entity *entity = &vdev->entity;
1130
1131 if (WARN_ON(entity->num_pads != 1))
1132 return;
1133
1134 return media_pipeline_stop(pad: &entity->pads[0]);
1135}
1136EXPORT_SYMBOL_GPL(video_device_pipeline_stop);
1137
1138void __video_device_pipeline_stop(struct video_device *vdev)
1139{
1140 struct media_entity *entity = &vdev->entity;
1141
1142 if (WARN_ON(entity->num_pads != 1))
1143 return;
1144
1145 return __media_pipeline_stop(pad: &entity->pads[0]);
1146}
1147EXPORT_SYMBOL_GPL(__video_device_pipeline_stop);
1148
1149__must_check int video_device_pipeline_alloc_start(struct video_device *vdev)
1150{
1151 struct media_entity *entity = &vdev->entity;
1152
1153 if (entity->num_pads != 1)
1154 return -ENODEV;
1155
1156 return media_pipeline_alloc_start(pad: &entity->pads[0]);
1157}
1158EXPORT_SYMBOL_GPL(video_device_pipeline_alloc_start);
1159
1160struct media_pipeline *video_device_pipeline(struct video_device *vdev)
1161{
1162 struct media_entity *entity = &vdev->entity;
1163
1164 if (WARN_ON(entity->num_pads != 1))
1165 return NULL;
1166
1167 return media_pad_pipeline(pad: &entity->pads[0]);
1168}
1169EXPORT_SYMBOL_GPL(video_device_pipeline);
1170
1171#endif /* CONFIG_MEDIA_CONTROLLER */
1172
1173/*
1174 * Initialise video for linux
1175 */
1176static int __init videodev_init(void)
1177{
1178 dev_t dev = MKDEV(VIDEO_MAJOR, 0);
1179 int ret;
1180
1181 pr_info("Linux video capture interface: v2.00\n");
1182 ret = register_chrdev_region(dev, VIDEO_NUM_DEVICES, VIDEO_NAME);
1183 if (ret < 0) {
1184 pr_warn("videodev: unable to get major %d\n",
1185 VIDEO_MAJOR);
1186 return ret;
1187 }
1188
1189 ret = class_register(class: &video_class);
1190 if (ret < 0) {
1191 unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
1192 pr_warn("video_dev: class_register failed\n");
1193 return -EIO;
1194 }
1195
1196 return 0;
1197}
1198
1199static void __exit videodev_exit(void)
1200{
1201 dev_t dev = MKDEV(VIDEO_MAJOR, 0);
1202
1203 class_unregister(class: &video_class);
1204 unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
1205}
1206
1207subsys_initcall(videodev_init);
1208module_exit(videodev_exit)
1209
1210MODULE_AUTHOR("Alan Cox, Mauro Carvalho Chehab <mchehab@kernel.org>, Bill Dirks, Justin Schoeman, Gerd Knorr");
1211MODULE_DESCRIPTION("Video4Linux2 core driver");
1212MODULE_LICENSE("GPL");
1213MODULE_ALIAS_CHARDEV_MAJOR(VIDEO_MAJOR);
1214

source code of linux/drivers/media/v4l2-core/v4l2-dev.c