1 /*
2  * V4L2 sub-device
3  *
4  * Copyright (C) 2010 Nokia Corporation
5  *
6  * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
7  *	    Sakari Ailus <sakari.ailus@iki.fi>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  */
18 
19 #include <linux/ioctl.h>
20 #include <linux/mm.h>
21 #include <linux/slab.h>
22 #include <linux/types.h>
23 #include <linux/videodev2.h>
24 #include <linux/export.h>
25 
26 #include <media/v4l2-ctrls.h>
27 #include <media/v4l2-device.h>
28 #include <media/v4l2-ioctl.h>
29 #include <media/v4l2-fh.h>
30 #include <media/v4l2-event.h>
31 
32 static int subdev_fh_init(struct v4l2_subdev_fh *fh, struct v4l2_subdev *sd)
33 {
34 #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
35 	if (sd->entity.num_pads) {
36 		fh->pad = v4l2_subdev_alloc_pad_config(sd);
37 		if (fh->pad == NULL)
38 			return -ENOMEM;
39 	}
40 #endif
41 	return 0;
42 }
43 
44 static void subdev_fh_free(struct v4l2_subdev_fh *fh)
45 {
46 #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
47 	v4l2_subdev_free_pad_config(fh->pad);
48 	fh->pad = NULL;
49 #endif
50 }
51 
52 static int subdev_open(struct file *file)
53 {
54 	struct video_device *vdev = video_devdata(file);
55 	struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
56 	struct v4l2_subdev_fh *subdev_fh;
57 #if defined(CONFIG_MEDIA_CONTROLLER)
58 	struct media_entity *entity = NULL;
59 #endif
60 	int ret;
61 
62 	subdev_fh = kzalloc(sizeof(*subdev_fh), GFP_KERNEL);
63 	if (subdev_fh == NULL)
64 		return -ENOMEM;
65 
66 	ret = subdev_fh_init(subdev_fh, sd);
67 	if (ret) {
68 		kfree(subdev_fh);
69 		return ret;
70 	}
71 
72 	v4l2_fh_init(&subdev_fh->vfh, vdev);
73 	v4l2_fh_add(&subdev_fh->vfh);
74 	file->private_data = &subdev_fh->vfh;
75 #if defined(CONFIG_MEDIA_CONTROLLER)
76 	if (sd->v4l2_dev->mdev) {
77 		entity = media_entity_get(&sd->entity);
78 		if (!entity) {
79 			ret = -EBUSY;
80 			goto err;
81 		}
82 	}
83 #endif
84 
85 	if (sd->internal_ops && sd->internal_ops->open) {
86 		ret = sd->internal_ops->open(sd, subdev_fh);
87 		if (ret < 0)
88 			goto err;
89 	}
90 
91 	return 0;
92 
93 err:
94 #if defined(CONFIG_MEDIA_CONTROLLER)
95 	media_entity_put(entity);
96 #endif
97 	v4l2_fh_del(&subdev_fh->vfh);
98 	v4l2_fh_exit(&subdev_fh->vfh);
99 	subdev_fh_free(subdev_fh);
100 	kfree(subdev_fh);
101 
102 	return ret;
103 }
104 
105 static int subdev_close(struct file *file)
106 {
107 	struct video_device *vdev = video_devdata(file);
108 	struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
109 	struct v4l2_fh *vfh = file->private_data;
110 	struct v4l2_subdev_fh *subdev_fh = to_v4l2_subdev_fh(vfh);
111 
112 	if (sd->internal_ops && sd->internal_ops->close)
113 		sd->internal_ops->close(sd, subdev_fh);
114 #if defined(CONFIG_MEDIA_CONTROLLER)
115 	if (sd->v4l2_dev->mdev)
116 		media_entity_put(&sd->entity);
117 #endif
118 	v4l2_fh_del(vfh);
119 	v4l2_fh_exit(vfh);
120 	subdev_fh_free(subdev_fh);
121 	kfree(subdev_fh);
122 	file->private_data = NULL;
123 
124 	return 0;
125 }
126 
127 #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
128 static int check_format(struct v4l2_subdev *sd,
129 			struct v4l2_subdev_format *format)
130 {
131 	if (format->which != V4L2_SUBDEV_FORMAT_TRY &&
132 	    format->which != V4L2_SUBDEV_FORMAT_ACTIVE)
133 		return -EINVAL;
134 
135 	if (format->pad >= sd->entity.num_pads)
136 		return -EINVAL;
137 
138 	return 0;
139 }
140 
141 static int check_crop(struct v4l2_subdev *sd, struct v4l2_subdev_crop *crop)
142 {
143 	if (crop->which != V4L2_SUBDEV_FORMAT_TRY &&
144 	    crop->which != V4L2_SUBDEV_FORMAT_ACTIVE)
145 		return -EINVAL;
146 
147 	if (crop->pad >= sd->entity.num_pads)
148 		return -EINVAL;
149 
150 	return 0;
151 }
152 
153 static int check_selection(struct v4l2_subdev *sd,
154 			   struct v4l2_subdev_selection *sel)
155 {
156 	if (sel->which != V4L2_SUBDEV_FORMAT_TRY &&
157 	    sel->which != V4L2_SUBDEV_FORMAT_ACTIVE)
158 		return -EINVAL;
159 
160 	if (sel->pad >= sd->entity.num_pads)
161 		return -EINVAL;
162 
163 	return 0;
164 }
165 
166 static int check_edid(struct v4l2_subdev *sd, struct v4l2_subdev_edid *edid)
167 {
168 	if (edid->pad >= sd->entity.num_pads)
169 		return -EINVAL;
170 
171 	if (edid->blocks && edid->edid == NULL)
172 		return -EINVAL;
173 
174 	return 0;
175 }
176 #endif
177 
178 static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
179 {
180 	struct video_device *vdev = video_devdata(file);
181 	struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
182 	struct v4l2_fh *vfh = file->private_data;
183 #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
184 	struct v4l2_subdev_fh *subdev_fh = to_v4l2_subdev_fh(vfh);
185 	int rval;
186 #endif
187 
188 	switch (cmd) {
189 	case VIDIOC_QUERYCTRL:
190 		/*
191 		 * TODO: this really should be folded into v4l2_queryctrl (this
192 		 * currently returns -EINVAL for NULL control handlers).
193 		 * However, v4l2_queryctrl() is still called directly by
194 		 * drivers as well and until that has been addressed I believe
195 		 * it is safer to do the check here. The same is true for the
196 		 * other control ioctls below.
197 		 */
198 		if (!vfh->ctrl_handler)
199 			return -ENOTTY;
200 		return v4l2_queryctrl(vfh->ctrl_handler, arg);
201 
202 	case VIDIOC_QUERY_EXT_CTRL:
203 		if (!vfh->ctrl_handler)
204 			return -ENOTTY;
205 		return v4l2_query_ext_ctrl(vfh->ctrl_handler, arg);
206 
207 	case VIDIOC_QUERYMENU:
208 		if (!vfh->ctrl_handler)
209 			return -ENOTTY;
210 		return v4l2_querymenu(vfh->ctrl_handler, arg);
211 
212 	case VIDIOC_G_CTRL:
213 		if (!vfh->ctrl_handler)
214 			return -ENOTTY;
215 		return v4l2_g_ctrl(vfh->ctrl_handler, arg);
216 
217 	case VIDIOC_S_CTRL:
218 		if (!vfh->ctrl_handler)
219 			return -ENOTTY;
220 		return v4l2_s_ctrl(vfh, vfh->ctrl_handler, arg);
221 
222 	case VIDIOC_G_EXT_CTRLS:
223 		if (!vfh->ctrl_handler)
224 			return -ENOTTY;
225 		return v4l2_g_ext_ctrls(vfh->ctrl_handler, arg);
226 
227 	case VIDIOC_S_EXT_CTRLS:
228 		if (!vfh->ctrl_handler)
229 			return -ENOTTY;
230 		return v4l2_s_ext_ctrls(vfh, vfh->ctrl_handler, arg);
231 
232 	case VIDIOC_TRY_EXT_CTRLS:
233 		if (!vfh->ctrl_handler)
234 			return -ENOTTY;
235 		return v4l2_try_ext_ctrls(vfh->ctrl_handler, arg);
236 
237 	case VIDIOC_DQEVENT:
238 		if (!(sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS))
239 			return -ENOIOCTLCMD;
240 
241 		return v4l2_event_dequeue(vfh, arg, file->f_flags & O_NONBLOCK);
242 
243 	case VIDIOC_SUBSCRIBE_EVENT:
244 		return v4l2_subdev_call(sd, core, subscribe_event, vfh, arg);
245 
246 	case VIDIOC_UNSUBSCRIBE_EVENT:
247 		return v4l2_subdev_call(sd, core, unsubscribe_event, vfh, arg);
248 
249 #ifdef CONFIG_VIDEO_ADV_DEBUG
250 	case VIDIOC_DBG_G_REGISTER:
251 	{
252 		struct v4l2_dbg_register *p = arg;
253 
254 		if (!capable(CAP_SYS_ADMIN))
255 			return -EPERM;
256 		return v4l2_subdev_call(sd, core, g_register, p);
257 	}
258 	case VIDIOC_DBG_S_REGISTER:
259 	{
260 		struct v4l2_dbg_register *p = arg;
261 
262 		if (!capable(CAP_SYS_ADMIN))
263 			return -EPERM;
264 		return v4l2_subdev_call(sd, core, s_register, p);
265 	}
266 	case VIDIOC_DBG_G_CHIP_INFO:
267 	{
268 		struct v4l2_dbg_chip_info *p = arg;
269 
270 		if (p->match.type != V4L2_CHIP_MATCH_SUBDEV || p->match.addr)
271 			return -EINVAL;
272 		if (sd->ops->core && sd->ops->core->s_register)
273 			p->flags |= V4L2_CHIP_FL_WRITABLE;
274 		if (sd->ops->core && sd->ops->core->g_register)
275 			p->flags |= V4L2_CHIP_FL_READABLE;
276 		strlcpy(p->name, sd->name, sizeof(p->name));
277 		return 0;
278 	}
279 #endif
280 
281 	case VIDIOC_LOG_STATUS: {
282 		int ret;
283 
284 		pr_info("%s: =================  START STATUS  =================\n",
285 			sd->name);
286 		ret = v4l2_subdev_call(sd, core, log_status);
287 		pr_info("%s: ==================  END STATUS  ==================\n",
288 			sd->name);
289 		return ret;
290 	}
291 
292 #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
293 	case VIDIOC_SUBDEV_G_FMT: {
294 		struct v4l2_subdev_format *format = arg;
295 
296 		rval = check_format(sd, format);
297 		if (rval)
298 			return rval;
299 
300 		memset(format->reserved, 0, sizeof(format->reserved));
301 		memset(format->format.reserved, 0, sizeof(format->format.reserved));
302 		return v4l2_subdev_call(sd, pad, get_fmt, subdev_fh->pad, format);
303 	}
304 
305 	case VIDIOC_SUBDEV_S_FMT: {
306 		struct v4l2_subdev_format *format = arg;
307 
308 		rval = check_format(sd, format);
309 		if (rval)
310 			return rval;
311 
312 		memset(format->reserved, 0, sizeof(format->reserved));
313 		memset(format->format.reserved, 0, sizeof(format->format.reserved));
314 		return v4l2_subdev_call(sd, pad, set_fmt, subdev_fh->pad, format);
315 	}
316 
317 	case VIDIOC_SUBDEV_G_CROP: {
318 		struct v4l2_subdev_crop *crop = arg;
319 		struct v4l2_subdev_selection sel;
320 
321 		rval = check_crop(sd, crop);
322 		if (rval)
323 			return rval;
324 
325 		memset(crop->reserved, 0, sizeof(crop->reserved));
326 		memset(&sel, 0, sizeof(sel));
327 		sel.which = crop->which;
328 		sel.pad = crop->pad;
329 		sel.target = V4L2_SEL_TGT_CROP;
330 
331 		rval = v4l2_subdev_call(
332 			sd, pad, get_selection, subdev_fh->pad, &sel);
333 
334 		crop->rect = sel.r;
335 
336 		return rval;
337 	}
338 
339 	case VIDIOC_SUBDEV_S_CROP: {
340 		struct v4l2_subdev_crop *crop = arg;
341 		struct v4l2_subdev_selection sel;
342 
343 		memset(crop->reserved, 0, sizeof(crop->reserved));
344 		rval = check_crop(sd, crop);
345 		if (rval)
346 			return rval;
347 
348 		memset(&sel, 0, sizeof(sel));
349 		sel.which = crop->which;
350 		sel.pad = crop->pad;
351 		sel.target = V4L2_SEL_TGT_CROP;
352 		sel.r = crop->rect;
353 
354 		rval = v4l2_subdev_call(
355 			sd, pad, set_selection, subdev_fh->pad, &sel);
356 
357 		crop->rect = sel.r;
358 
359 		return rval;
360 	}
361 
362 	case VIDIOC_SUBDEV_ENUM_MBUS_CODE: {
363 		struct v4l2_subdev_mbus_code_enum *code = arg;
364 
365 		if (code->which != V4L2_SUBDEV_FORMAT_TRY &&
366 		    code->which != V4L2_SUBDEV_FORMAT_ACTIVE)
367 			return -EINVAL;
368 
369 		if (code->pad >= sd->entity.num_pads)
370 			return -EINVAL;
371 
372 		memset(code->reserved, 0, sizeof(code->reserved));
373 		return v4l2_subdev_call(sd, pad, enum_mbus_code, subdev_fh->pad,
374 					code);
375 	}
376 
377 	case VIDIOC_SUBDEV_ENUM_FRAME_SIZE: {
378 		struct v4l2_subdev_frame_size_enum *fse = arg;
379 
380 		if (fse->which != V4L2_SUBDEV_FORMAT_TRY &&
381 		    fse->which != V4L2_SUBDEV_FORMAT_ACTIVE)
382 			return -EINVAL;
383 
384 		if (fse->pad >= sd->entity.num_pads)
385 			return -EINVAL;
386 
387 		memset(fse->reserved, 0, sizeof(fse->reserved));
388 		return v4l2_subdev_call(sd, pad, enum_frame_size, subdev_fh->pad,
389 					fse);
390 	}
391 
392 	case VIDIOC_SUBDEV_G_FRAME_INTERVAL: {
393 		struct v4l2_subdev_frame_interval *fi = arg;
394 
395 		if (fi->pad >= sd->entity.num_pads)
396 			return -EINVAL;
397 
398 		memset(fi->reserved, 0, sizeof(fi->reserved));
399 		return v4l2_subdev_call(sd, video, g_frame_interval, arg);
400 	}
401 
402 	case VIDIOC_SUBDEV_S_FRAME_INTERVAL: {
403 		struct v4l2_subdev_frame_interval *fi = arg;
404 
405 		if (fi->pad >= sd->entity.num_pads)
406 			return -EINVAL;
407 
408 		memset(fi->reserved, 0, sizeof(fi->reserved));
409 		return v4l2_subdev_call(sd, video, s_frame_interval, arg);
410 	}
411 
412 	case VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL: {
413 		struct v4l2_subdev_frame_interval_enum *fie = arg;
414 
415 		if (fie->which != V4L2_SUBDEV_FORMAT_TRY &&
416 		    fie->which != V4L2_SUBDEV_FORMAT_ACTIVE)
417 			return -EINVAL;
418 
419 		if (fie->pad >= sd->entity.num_pads)
420 			return -EINVAL;
421 
422 		memset(fie->reserved, 0, sizeof(fie->reserved));
423 		return v4l2_subdev_call(sd, pad, enum_frame_interval, subdev_fh->pad,
424 					fie);
425 	}
426 
427 	case VIDIOC_SUBDEV_G_SELECTION: {
428 		struct v4l2_subdev_selection *sel = arg;
429 
430 		rval = check_selection(sd, sel);
431 		if (rval)
432 			return rval;
433 
434 		memset(sel->reserved, 0, sizeof(sel->reserved));
435 		return v4l2_subdev_call(
436 			sd, pad, get_selection, subdev_fh->pad, sel);
437 	}
438 
439 	case VIDIOC_SUBDEV_S_SELECTION: {
440 		struct v4l2_subdev_selection *sel = arg;
441 
442 		rval = check_selection(sd, sel);
443 		if (rval)
444 			return rval;
445 
446 		memset(sel->reserved, 0, sizeof(sel->reserved));
447 		return v4l2_subdev_call(
448 			sd, pad, set_selection, subdev_fh->pad, sel);
449 	}
450 
451 	case VIDIOC_G_EDID: {
452 		struct v4l2_subdev_edid *edid = arg;
453 
454 		rval = check_edid(sd, edid);
455 		if (rval)
456 			return rval;
457 
458 		return v4l2_subdev_call(sd, pad, get_edid, edid);
459 	}
460 
461 	case VIDIOC_S_EDID: {
462 		struct v4l2_subdev_edid *edid = arg;
463 
464 		rval = check_edid(sd, edid);
465 		if (rval)
466 			return rval;
467 
468 		return v4l2_subdev_call(sd, pad, set_edid, edid);
469 	}
470 
471 	case VIDIOC_SUBDEV_DV_TIMINGS_CAP: {
472 		struct v4l2_dv_timings_cap *cap = arg;
473 
474 		if (cap->pad >= sd->entity.num_pads)
475 			return -EINVAL;
476 
477 		return v4l2_subdev_call(sd, pad, dv_timings_cap, cap);
478 	}
479 
480 	case VIDIOC_SUBDEV_ENUM_DV_TIMINGS: {
481 		struct v4l2_enum_dv_timings *dvt = arg;
482 
483 		if (dvt->pad >= sd->entity.num_pads)
484 			return -EINVAL;
485 
486 		return v4l2_subdev_call(sd, pad, enum_dv_timings, dvt);
487 	}
488 
489 	case VIDIOC_SUBDEV_QUERY_DV_TIMINGS:
490 		return v4l2_subdev_call(sd, video, query_dv_timings, arg);
491 
492 	case VIDIOC_SUBDEV_G_DV_TIMINGS:
493 		return v4l2_subdev_call(sd, video, g_dv_timings, arg);
494 
495 	case VIDIOC_SUBDEV_S_DV_TIMINGS:
496 		return v4l2_subdev_call(sd, video, s_dv_timings, arg);
497 #endif
498 	default:
499 		return v4l2_subdev_call(sd, core, ioctl, cmd, arg);
500 	}
501 
502 	return 0;
503 }
504 
505 static long subdev_ioctl(struct file *file, unsigned int cmd,
506 	unsigned long arg)
507 {
508 	return video_usercopy(file, cmd, arg, subdev_do_ioctl);
509 }
510 
511 #ifdef CONFIG_COMPAT
512 static long subdev_compat_ioctl32(struct file *file, unsigned int cmd,
513 	unsigned long arg)
514 {
515 	struct video_device *vdev = video_devdata(file);
516 	struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
517 
518 	return v4l2_subdev_call(sd, core, compat_ioctl32, cmd, arg);
519 }
520 #endif
521 
522 static __poll_t subdev_poll(struct file *file, poll_table *wait)
523 {
524 	struct video_device *vdev = video_devdata(file);
525 	struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
526 	struct v4l2_fh *fh = file->private_data;
527 
528 	if (!(sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS))
529 		return EPOLLERR;
530 
531 	poll_wait(file, &fh->wait, wait);
532 
533 	if (v4l2_event_pending(fh))
534 		return EPOLLPRI;
535 
536 	return 0;
537 }
538 
539 const struct v4l2_file_operations v4l2_subdev_fops = {
540 	.owner = THIS_MODULE,
541 	.open = subdev_open,
542 	.unlocked_ioctl = subdev_ioctl,
543 #ifdef CONFIG_COMPAT
544 	.compat_ioctl32 = subdev_compat_ioctl32,
545 #endif
546 	.release = subdev_close,
547 	.poll = subdev_poll,
548 };
549 
550 #ifdef CONFIG_MEDIA_CONTROLLER
551 int v4l2_subdev_link_validate_default(struct v4l2_subdev *sd,
552 				      struct media_link *link,
553 				      struct v4l2_subdev_format *source_fmt,
554 				      struct v4l2_subdev_format *sink_fmt)
555 {
556 	/* The width, height and code must match. */
557 	if (source_fmt->format.width != sink_fmt->format.width
558 	    || source_fmt->format.height != sink_fmt->format.height
559 	    || source_fmt->format.code != sink_fmt->format.code)
560 		return -EPIPE;
561 
562 	/* The field order must match, or the sink field order must be NONE
563 	 * to support interlaced hardware connected to bridges that support
564 	 * progressive formats only.
565 	 */
566 	if (source_fmt->format.field != sink_fmt->format.field &&
567 	    sink_fmt->format.field != V4L2_FIELD_NONE)
568 		return -EPIPE;
569 
570 	return 0;
571 }
572 EXPORT_SYMBOL_GPL(v4l2_subdev_link_validate_default);
573 
574 static int
575 v4l2_subdev_link_validate_get_format(struct media_pad *pad,
576 				     struct v4l2_subdev_format *fmt)
577 {
578 	if (is_media_entity_v4l2_subdev(pad->entity)) {
579 		struct v4l2_subdev *sd =
580 			media_entity_to_v4l2_subdev(pad->entity);
581 
582 		fmt->which = V4L2_SUBDEV_FORMAT_ACTIVE;
583 		fmt->pad = pad->index;
584 		return v4l2_subdev_call(sd, pad, get_fmt, NULL, fmt);
585 	}
586 
587 	WARN(pad->entity->function != MEDIA_ENT_F_IO_V4L,
588 	     "Driver bug! Wrong media entity type 0x%08x, entity %s\n",
589 	     pad->entity->function, pad->entity->name);
590 
591 	return -EINVAL;
592 }
593 
594 int v4l2_subdev_link_validate(struct media_link *link)
595 {
596 	struct v4l2_subdev *sink;
597 	struct v4l2_subdev_format sink_fmt, source_fmt;
598 	int rval;
599 
600 	rval = v4l2_subdev_link_validate_get_format(
601 		link->source, &source_fmt);
602 	if (rval < 0)
603 		return 0;
604 
605 	rval = v4l2_subdev_link_validate_get_format(
606 		link->sink, &sink_fmt);
607 	if (rval < 0)
608 		return 0;
609 
610 	sink = media_entity_to_v4l2_subdev(link->sink->entity);
611 
612 	rval = v4l2_subdev_call(sink, pad, link_validate, link,
613 				&source_fmt, &sink_fmt);
614 	if (rval != -ENOIOCTLCMD)
615 		return rval;
616 
617 	return v4l2_subdev_link_validate_default(
618 		sink, link, &source_fmt, &sink_fmt);
619 }
620 EXPORT_SYMBOL_GPL(v4l2_subdev_link_validate);
621 
622 struct v4l2_subdev_pad_config *
623 v4l2_subdev_alloc_pad_config(struct v4l2_subdev *sd)
624 {
625 	struct v4l2_subdev_pad_config *cfg;
626 	int ret;
627 
628 	if (!sd->entity.num_pads)
629 		return NULL;
630 
631 	cfg = kvmalloc_array(sd->entity.num_pads, sizeof(*cfg),
632 			     GFP_KERNEL | __GFP_ZERO);
633 	if (!cfg)
634 		return NULL;
635 
636 	ret = v4l2_subdev_call(sd, pad, init_cfg, cfg);
637 	if (ret < 0 && ret != -ENOIOCTLCMD) {
638 		kvfree(cfg);
639 		return NULL;
640 	}
641 
642 	return cfg;
643 }
644 EXPORT_SYMBOL_GPL(v4l2_subdev_alloc_pad_config);
645 
646 void v4l2_subdev_free_pad_config(struct v4l2_subdev_pad_config *cfg)
647 {
648 	kvfree(cfg);
649 }
650 EXPORT_SYMBOL_GPL(v4l2_subdev_free_pad_config);
651 #endif /* CONFIG_MEDIA_CONTROLLER */
652 
653 void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops)
654 {
655 	INIT_LIST_HEAD(&sd->list);
656 	BUG_ON(!ops);
657 	sd->ops = ops;
658 	sd->v4l2_dev = NULL;
659 	sd->flags = 0;
660 	sd->name[0] = '\0';
661 	sd->grp_id = 0;
662 	sd->dev_priv = NULL;
663 	sd->host_priv = NULL;
664 #if defined(CONFIG_MEDIA_CONTROLLER)
665 	sd->entity.name = sd->name;
666 	sd->entity.obj_type = MEDIA_ENTITY_TYPE_V4L2_SUBDEV;
667 	sd->entity.function = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
668 #endif
669 }
670 EXPORT_SYMBOL(v4l2_subdev_init);
671 
672 void v4l2_subdev_notify_event(struct v4l2_subdev *sd,
673 			      const struct v4l2_event *ev)
674 {
675 	v4l2_event_queue(sd->devnode, ev);
676 	v4l2_subdev_notify(sd, V4L2_DEVICE_NOTIFY_EVENT, (void *)ev);
677 }
678 EXPORT_SYMBOL_GPL(v4l2_subdev_notify_event);
679