xref: /linux/drivers/usb/gadget/function/uvc_v4l2.c (revision 566ab427f827b0256d3e8ce0235d088e6a9c28bd) 
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *	uvc_v4l2.c  --  USB Video Class Gadget driver
4  *
5  *	Copyright (C) 2009-2010
6  *	    Laurent Pinchart (laurent.pinchart@ideasonboard.com)
7  */
8 
9 #include <linux/device.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/list.h>
13 #include <linux/usb/g_uvc.h>
14 #include <linux/usb/uvc.h>
15 #include <linux/videodev2.h>
16 #include <linux/vmalloc.h>
17 #include <linux/wait.h>
18 
19 #include <media/v4l2-dev.h>
20 #include <media/v4l2-event.h>
21 #include <media/v4l2-ioctl.h>
22 
23 #include "f_uvc.h"
24 #include "uvc.h"
25 #include "uvc_queue.h"
26 #include "uvc_video.h"
27 #include "uvc_v4l2.h"
28 #include "uvc_configfs.h"
29 
30 static const struct uvc_format_desc *to_uvc_format(struct uvcg_format *uformat)
31 {
32 	char guid[16] = UVC_GUID_FORMAT_MJPEG;
33 	const struct uvc_format_desc *format;
34 	struct uvcg_uncompressed *unc;
35 
36 	if (uformat->type == UVCG_UNCOMPRESSED) {
37 		unc = to_uvcg_uncompressed(&uformat->group.cg_item);
38 		if (!unc)
39 			return ERR_PTR(-EINVAL);
40 
41 		memcpy(guid, unc->desc.guidFormat, sizeof(guid));
42 	}
43 
44 	format = uvc_format_by_guid(guid);
45 	if (!format)
46 		return ERR_PTR(-EINVAL);
47 
48 	return format;
49 }
50 
51 static int uvc_v4l2_get_bytesperline(struct uvcg_format *uformat,
52 			      struct uvcg_frame *uframe)
53 {
54 	struct uvcg_uncompressed *u;
55 
56 	if (uformat->type == UVCG_UNCOMPRESSED) {
57 		u = to_uvcg_uncompressed(&uformat->group.cg_item);
58 		if (!u)
59 			return 0;
60 
61 		return u->desc.bBitsPerPixel * uframe->frame.w_width / 8;
62 	}
63 
64 	return 0;
65 }
66 
67 static int uvc_get_frame_size(struct uvcg_format *uformat,
68 		       struct uvcg_frame *uframe)
69 {
70 	unsigned int bpl = uvc_v4l2_get_bytesperline(uformat, uframe);
71 
72 	return bpl ? bpl * uframe->frame.w_height :
73 		uframe->frame.dw_max_video_frame_buffer_size;
74 }
75 
76 static struct uvcg_format *find_format_by_index(struct uvc_device *uvc, int index)
77 {
78 	struct uvcg_format_ptr *format;
79 	struct uvcg_format *uformat = NULL;
80 	int i = 1;
81 
82 	list_for_each_entry(format, &uvc->header->formats, entry) {
83 		if (index == i) {
84 			uformat = format->fmt;
85 			break;
86 		}
87 		i++;
88 	}
89 
90 	return uformat;
91 }
92 
93 static struct uvcg_frame *find_frame_by_index(struct uvc_device *uvc,
94 				       struct uvcg_format *uformat,
95 				       int index)
96 {
97 	struct uvcg_format_ptr *format;
98 	struct uvcg_frame_ptr *frame;
99 	struct uvcg_frame *uframe = NULL;
100 
101 	list_for_each_entry(format, &uvc->header->formats, entry) {
102 		if (format->fmt->type != uformat->type)
103 			continue;
104 		list_for_each_entry(frame, &format->fmt->frames, entry) {
105 			if (index == frame->frm->frame.b_frame_index) {
106 				uframe = frame->frm;
107 				break;
108 			}
109 		}
110 	}
111 
112 	return uframe;
113 }
114 
115 static struct uvcg_format *find_format_by_pix(struct uvc_device *uvc,
116 					      u32 pixelformat)
117 {
118 	struct uvcg_format_ptr *format;
119 	struct uvcg_format *uformat = NULL;
120 
121 	list_for_each_entry(format, &uvc->header->formats, entry) {
122 		const struct uvc_format_desc *fmtdesc = to_uvc_format(format->fmt);
123 
124 		if (IS_ERR(fmtdesc))
125 			continue;
126 
127 		if (fmtdesc->fcc == pixelformat) {
128 			uformat = format->fmt;
129 			break;
130 		}
131 	}
132 
133 	return uformat;
134 }
135 
136 static struct uvcg_frame *find_closest_frame_by_size(struct uvc_device *uvc,
137 					   struct uvcg_format *uformat,
138 					   u16 rw, u16 rh)
139 {
140 	struct uvc_video *video = &uvc->video;
141 	struct uvcg_format_ptr *format;
142 	struct uvcg_frame_ptr *frame;
143 	struct uvcg_frame *uframe = NULL;
144 	unsigned int d, maxd;
145 
146 	/* Find the closest image size. The distance between image sizes is
147 	 * the size in pixels of the non-overlapping regions between the
148 	 * requested size and the frame-specified size.
149 	 */
150 	maxd = (unsigned int)-1;
151 
152 	list_for_each_entry(format, &uvc->header->formats, entry) {
153 		if (format->fmt->type != uformat->type)
154 			continue;
155 
156 		list_for_each_entry(frame, &format->fmt->frames, entry) {
157 			u16 w, h;
158 
159 			w = frame->frm->frame.w_width;
160 			h = frame->frm->frame.w_height;
161 
162 			d = min(w, rw) * min(h, rh);
163 			d = w*h + rw*rh - 2*d;
164 			if (d < maxd) {
165 				maxd = d;
166 				uframe = frame->frm;
167 			}
168 
169 			if (maxd == 0)
170 				break;
171 		}
172 	}
173 
174 	if (!uframe)
175 		uvcg_dbg(&video->uvc->func, "Unsupported size %ux%u\n", rw, rh);
176 
177 	return uframe;
178 }
179 
180 /* --------------------------------------------------------------------------
181  * Requests handling
182  */
183 
184 static int
185 uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
186 {
187 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
188 	struct usb_request *req = uvc->control_req;
189 
190 	if (data->length < 0)
191 		return usb_ep_set_halt(cdev->gadget->ep0);
192 
193 	req->length = min_t(unsigned int, uvc->event_length, data->length);
194 	req->zero = data->length < uvc->event_length;
195 
196 	memcpy(req->buf, data->data, req->length);
197 
198 	return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
199 }
200 
201 /* --------------------------------------------------------------------------
202  * V4L2 ioctls
203  */
204 
205 static int
206 uvc_v4l2_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
207 {
208 	struct video_device *vdev = video_devdata(file);
209 	struct uvc_device *uvc = video_get_drvdata(vdev);
210 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
211 
212 	strscpy(cap->driver, "g_uvc", sizeof(cap->driver));
213 	strscpy(cap->card, cdev->gadget->name, sizeof(cap->card));
214 	strscpy(cap->bus_info, dev_name(&cdev->gadget->dev),
215 		sizeof(cap->bus_info));
216 	return 0;
217 }
218 
219 static int
220 uvc_v4l2_get_format(struct file *file, void *fh, struct v4l2_format *fmt)
221 {
222 	struct video_device *vdev = video_devdata(file);
223 	struct uvc_device *uvc = video_get_drvdata(vdev);
224 	struct uvc_video *video = &uvc->video;
225 
226 	fmt->fmt.pix.pixelformat = video->fcc;
227 	fmt->fmt.pix.width = video->width;
228 	fmt->fmt.pix.height = video->height;
229 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
230 	fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
231 	fmt->fmt.pix.sizeimage = video->imagesize;
232 	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
233 	fmt->fmt.pix.priv = 0;
234 
235 	return 0;
236 }
237 
238 static int
239 uvc_v4l2_try_format(struct file *file, void *fh, struct v4l2_format *fmt)
240 {
241 	struct video_device *vdev = video_devdata(file);
242 	struct uvc_device *uvc = video_get_drvdata(vdev);
243 	struct uvc_video *video = &uvc->video;
244 	struct uvcg_format *uformat;
245 	struct uvcg_frame *uframe;
246 	const struct uvc_format_desc *fmtdesc;
247 	u8 *fcc;
248 
249 	if (fmt->type != video->queue.queue.type)
250 		return -EINVAL;
251 
252 	fcc = (u8 *)&fmt->fmt.pix.pixelformat;
253 	uvcg_dbg(&uvc->func, "Trying format 0x%08x (%c%c%c%c): %ux%u\n",
254 		fmt->fmt.pix.pixelformat,
255 		fcc[0], fcc[1], fcc[2], fcc[3],
256 		fmt->fmt.pix.width, fmt->fmt.pix.height);
257 
258 	uformat = find_format_by_pix(uvc, fmt->fmt.pix.pixelformat);
259 	if (!uformat)
260 		return -EINVAL;
261 
262 	uframe = find_closest_frame_by_size(uvc, uformat,
263 				fmt->fmt.pix.width, fmt->fmt.pix.height);
264 	if (!uframe)
265 		return -EINVAL;
266 
267 	if (uformat->type == UVCG_UNCOMPRESSED) {
268 		struct uvcg_uncompressed *u =
269 			to_uvcg_uncompressed(&uformat->group.cg_item);
270 		if (!u)
271 			return 0;
272 
273 		v4l2_fill_pixfmt(&fmt->fmt.pix, fmt->fmt.pix.pixelformat,
274 				 uframe->frame.w_width, uframe->frame.w_height);
275 
276 		if (fmt->fmt.pix.sizeimage != (uvc_v4l2_get_bytesperline(uformat, uframe) *
277 						uframe->frame.w_height))
278 			return -EINVAL;
279 	} else {
280 		fmt->fmt.pix.width = uframe->frame.w_width;
281 		fmt->fmt.pix.height = uframe->frame.w_height;
282 		fmt->fmt.pix.bytesperline = uvc_v4l2_get_bytesperline(uformat, uframe);
283 		fmt->fmt.pix.sizeimage = uvc_get_frame_size(uformat, uframe);
284 		fmtdesc = to_uvc_format(uformat);
285 		if (IS_ERR(fmtdesc))
286 			return PTR_ERR(fmtdesc);
287 		fmt->fmt.pix.pixelformat = fmtdesc->fcc;
288 	}
289 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
290 	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
291 	fmt->fmt.pix.priv = 0;
292 
293 	return 0;
294 }
295 
296 static int
297 uvc_v4l2_set_format(struct file *file, void *fh, struct v4l2_format *fmt)
298 {
299 	struct video_device *vdev = video_devdata(file);
300 	struct uvc_device *uvc = video_get_drvdata(vdev);
301 	struct uvc_video *video = &uvc->video;
302 	int ret;
303 
304 	ret = uvc_v4l2_try_format(file, fh, fmt);
305 	if (ret)
306 		return ret;
307 
308 	video->fcc = fmt->fmt.pix.pixelformat;
309 	video->bpp = fmt->fmt.pix.bytesperline * 8 / video->width;
310 	video->width = fmt->fmt.pix.width;
311 	video->height = fmt->fmt.pix.height;
312 	video->imagesize = fmt->fmt.pix.sizeimage;
313 
314 	return ret;
315 }
316 
317 static int
318 uvc_v4l2_enum_frameintervals(struct file *file, void *fh,
319 		struct v4l2_frmivalenum *fival)
320 {
321 	struct video_device *vdev = video_devdata(file);
322 	struct uvc_device *uvc = video_get_drvdata(vdev);
323 	struct uvcg_format *uformat = NULL;
324 	struct uvcg_frame *uframe = NULL;
325 	struct uvcg_frame_ptr *frame;
326 
327 	uformat = find_format_by_pix(uvc, fival->pixel_format);
328 	if (!uformat)
329 		return -EINVAL;
330 
331 	list_for_each_entry(frame, &uformat->frames, entry) {
332 		if (frame->frm->frame.w_width == fival->width &&
333 		    frame->frm->frame.w_height == fival->height) {
334 			uframe = frame->frm;
335 			break;
336 		}
337 	}
338 	if (!uframe)
339 		return -EINVAL;
340 
341 	if (fival->index >= uframe->frame.b_frame_interval_type)
342 		return -EINVAL;
343 
344 	fival->discrete.numerator =
345 		uframe->dw_frame_interval[fival->index];
346 
347 	/* TODO: handle V4L2_FRMIVAL_TYPE_STEPWISE */
348 	fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
349 	fival->discrete.denominator = 10000000;
350 	v4l2_simplify_fraction(&fival->discrete.numerator,
351 		&fival->discrete.denominator, 8, 333);
352 
353 	return 0;
354 }
355 
356 static int
357 uvc_v4l2_enum_framesizes(struct file *file, void *fh,
358 		struct v4l2_frmsizeenum *fsize)
359 {
360 	struct video_device *vdev = video_devdata(file);
361 	struct uvc_device *uvc = video_get_drvdata(vdev);
362 	struct uvcg_format *uformat = NULL;
363 	struct uvcg_frame *uframe = NULL;
364 
365 	uformat = find_format_by_pix(uvc, fsize->pixel_format);
366 	if (!uformat)
367 		return -EINVAL;
368 
369 	if (fsize->index >= uformat->num_frames)
370 		return -EINVAL;
371 
372 	uframe = find_frame_by_index(uvc, uformat, fsize->index + 1);
373 	if (!uframe)
374 		return -EINVAL;
375 
376 	fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
377 	fsize->discrete.width = uframe->frame.w_width;
378 	fsize->discrete.height = uframe->frame.w_height;
379 
380 	return 0;
381 }
382 
383 static int
384 uvc_v4l2_enum_format(struct file *file, void *fh, struct v4l2_fmtdesc *f)
385 {
386 	struct video_device *vdev = video_devdata(file);
387 	struct uvc_device *uvc = video_get_drvdata(vdev);
388 	const struct uvc_format_desc *fmtdesc;
389 	struct uvcg_format *uformat;
390 
391 	if (f->index >= uvc->header->num_fmt)
392 		return -EINVAL;
393 
394 	uformat = find_format_by_index(uvc, f->index + 1);
395 	if (!uformat)
396 		return -EINVAL;
397 
398 	fmtdesc = to_uvc_format(uformat);
399 	if (IS_ERR(fmtdesc))
400 		return PTR_ERR(fmtdesc);
401 
402 	f->pixelformat = fmtdesc->fcc;
403 
404 	return 0;
405 }
406 
407 static int
408 uvc_v4l2_reqbufs(struct file *file, void *fh, struct v4l2_requestbuffers *b)
409 {
410 	struct video_device *vdev = video_devdata(file);
411 	struct uvc_device *uvc = video_get_drvdata(vdev);
412 	struct uvc_video *video = &uvc->video;
413 
414 	if (b->type != video->queue.queue.type)
415 		return -EINVAL;
416 
417 	return uvcg_alloc_buffers(&video->queue, b);
418 }
419 
420 static int
421 uvc_v4l2_querybuf(struct file *file, void *fh, struct v4l2_buffer *b)
422 {
423 	struct video_device *vdev = video_devdata(file);
424 	struct uvc_device *uvc = video_get_drvdata(vdev);
425 	struct uvc_video *video = &uvc->video;
426 
427 	return uvcg_query_buffer(&video->queue, b);
428 }
429 
430 static int
431 uvc_v4l2_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
432 {
433 	struct video_device *vdev = video_devdata(file);
434 	struct uvc_device *uvc = video_get_drvdata(vdev);
435 	struct uvc_video *video = &uvc->video;
436 	int ret;
437 
438 	ret = uvcg_queue_buffer(&video->queue, b);
439 	if (ret < 0)
440 		return ret;
441 
442 	if (uvc->state == UVC_STATE_STREAMING)
443 		queue_work(video->async_wq, &video->pump);
444 
445 	return ret;
446 }
447 
448 static int
449 uvc_v4l2_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b)
450 {
451 	struct video_device *vdev = video_devdata(file);
452 	struct uvc_device *uvc = video_get_drvdata(vdev);
453 	struct uvc_video *video = &uvc->video;
454 
455 	return uvcg_dequeue_buffer(&video->queue, b, file->f_flags & O_NONBLOCK);
456 }
457 
458 static int
459 uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
460 {
461 	struct video_device *vdev = video_devdata(file);
462 	struct uvc_device *uvc = video_get_drvdata(vdev);
463 	struct uvc_video *video = &uvc->video;
464 	int ret;
465 
466 	if (type != video->queue.queue.type)
467 		return -EINVAL;
468 
469 	/* Enable UVC video. */
470 	ret = uvcg_video_enable(video);
471 	if (ret < 0)
472 		return ret;
473 
474 	/*
475 	 * Complete the alternate setting selection setup phase now that
476 	 * userspace is ready to provide video frames.
477 	 */
478 	uvc_function_setup_continue(uvc, 0);
479 	uvc->state = UVC_STATE_STREAMING;
480 
481 	return 0;
482 }
483 
484 static int
485 uvc_v4l2_streamoff(struct file *file, void *fh, enum v4l2_buf_type type)
486 {
487 	struct video_device *vdev = video_devdata(file);
488 	struct uvc_device *uvc = video_get_drvdata(vdev);
489 	struct uvc_video *video = &uvc->video;
490 	int ret = 0;
491 
492 	if (type != video->queue.queue.type)
493 		return -EINVAL;
494 
495 	ret = uvcg_video_disable(video);
496 	if (ret < 0)
497 		return ret;
498 
499 	uvc->state = UVC_STATE_CONNECTED;
500 	uvc_function_setup_continue(uvc, 1);
501 	return 0;
502 }
503 
504 static int
505 uvc_v4l2_subscribe_event(struct v4l2_fh *fh,
506 			 const struct v4l2_event_subscription *sub)
507 {
508 	struct uvc_device *uvc = video_get_drvdata(fh->vdev);
509 	struct uvc_file_handle *handle = to_uvc_file_handle(fh);
510 	int ret;
511 
512 	if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
513 		return -EINVAL;
514 
515 	if (sub->type == UVC_EVENT_SETUP && uvc->func_connected)
516 		return -EBUSY;
517 
518 	ret = v4l2_event_subscribe(fh, sub, 2, NULL);
519 	if (ret < 0)
520 		return ret;
521 
522 	if (sub->type == UVC_EVENT_SETUP) {
523 		uvc->func_connected = true;
524 		handle->is_uvc_app_handle = true;
525 		uvc_function_connect(uvc);
526 	}
527 
528 	return 0;
529 }
530 
531 static void uvc_v4l2_disable(struct uvc_device *uvc)
532 {
533 	uvc_function_disconnect(uvc);
534 	uvcg_video_disable(&uvc->video);
535 	uvcg_free_buffers(&uvc->video.queue);
536 	uvc->func_connected = false;
537 	wake_up_interruptible(&uvc->func_connected_queue);
538 }
539 
540 static int
541 uvc_v4l2_unsubscribe_event(struct v4l2_fh *fh,
542 			   const struct v4l2_event_subscription *sub)
543 {
544 	struct uvc_device *uvc = video_get_drvdata(fh->vdev);
545 	struct uvc_file_handle *handle = to_uvc_file_handle(fh);
546 	int ret;
547 
548 	ret = v4l2_event_unsubscribe(fh, sub);
549 	if (ret < 0)
550 		return ret;
551 
552 	if (sub->type == UVC_EVENT_SETUP && handle->is_uvc_app_handle) {
553 		uvc_v4l2_disable(uvc);
554 		handle->is_uvc_app_handle = false;
555 	}
556 
557 	return 0;
558 }
559 
560 static long
561 uvc_v4l2_ioctl_default(struct file *file, void *fh, bool valid_prio,
562 		       unsigned int cmd, void *arg)
563 {
564 	struct video_device *vdev = video_devdata(file);
565 	struct uvc_device *uvc = video_get_drvdata(vdev);
566 
567 	switch (cmd) {
568 	case UVCIOC_SEND_RESPONSE:
569 		return uvc_send_response(uvc, arg);
570 
571 	default:
572 		return -ENOIOCTLCMD;
573 	}
574 }
575 
576 const struct v4l2_ioctl_ops uvc_v4l2_ioctl_ops = {
577 	.vidioc_querycap = uvc_v4l2_querycap,
578 	.vidioc_try_fmt_vid_out = uvc_v4l2_try_format,
579 	.vidioc_g_fmt_vid_out = uvc_v4l2_get_format,
580 	.vidioc_s_fmt_vid_out = uvc_v4l2_set_format,
581 	.vidioc_enum_frameintervals = uvc_v4l2_enum_frameintervals,
582 	.vidioc_enum_framesizes = uvc_v4l2_enum_framesizes,
583 	.vidioc_enum_fmt_vid_out = uvc_v4l2_enum_format,
584 	.vidioc_reqbufs = uvc_v4l2_reqbufs,
585 	.vidioc_querybuf = uvc_v4l2_querybuf,
586 	.vidioc_qbuf = uvc_v4l2_qbuf,
587 	.vidioc_dqbuf = uvc_v4l2_dqbuf,
588 	.vidioc_streamon = uvc_v4l2_streamon,
589 	.vidioc_streamoff = uvc_v4l2_streamoff,
590 	.vidioc_subscribe_event = uvc_v4l2_subscribe_event,
591 	.vidioc_unsubscribe_event = uvc_v4l2_unsubscribe_event,
592 	.vidioc_default = uvc_v4l2_ioctl_default,
593 };
594 
595 /* --------------------------------------------------------------------------
596  * V4L2
597  */
598 
599 static int
600 uvc_v4l2_open(struct file *file)
601 {
602 	struct video_device *vdev = video_devdata(file);
603 	struct uvc_device *uvc = video_get_drvdata(vdev);
604 	struct uvc_file_handle *handle;
605 
606 	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
607 	if (handle == NULL)
608 		return -ENOMEM;
609 
610 	v4l2_fh_init(&handle->vfh, vdev);
611 	v4l2_fh_add(&handle->vfh);
612 
613 	handle->device = &uvc->video;
614 	file->private_data = &handle->vfh;
615 
616 	return 0;
617 }
618 
619 static int
620 uvc_v4l2_release(struct file *file)
621 {
622 	struct video_device *vdev = video_devdata(file);
623 	struct uvc_device *uvc = video_get_drvdata(vdev);
624 	struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
625 	struct uvc_video *video = handle->device;
626 
627 	mutex_lock(&video->mutex);
628 	if (handle->is_uvc_app_handle)
629 		uvc_v4l2_disable(uvc);
630 	mutex_unlock(&video->mutex);
631 
632 	file->private_data = NULL;
633 	v4l2_fh_del(&handle->vfh);
634 	v4l2_fh_exit(&handle->vfh);
635 	kfree(handle);
636 
637 	return 0;
638 }
639 
640 static int
641 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
642 {
643 	struct video_device *vdev = video_devdata(file);
644 	struct uvc_device *uvc = video_get_drvdata(vdev);
645 
646 	return uvcg_queue_mmap(&uvc->video.queue, vma);
647 }
648 
649 static __poll_t
650 uvc_v4l2_poll(struct file *file, poll_table *wait)
651 {
652 	struct video_device *vdev = video_devdata(file);
653 	struct uvc_device *uvc = video_get_drvdata(vdev);
654 
655 	return uvcg_queue_poll(&uvc->video.queue, file, wait);
656 }
657 
658 #ifndef CONFIG_MMU
659 static unsigned long uvcg_v4l2_get_unmapped_area(struct file *file,
660 		unsigned long addr, unsigned long len, unsigned long pgoff,
661 		unsigned long flags)
662 {
663 	struct video_device *vdev = video_devdata(file);
664 	struct uvc_device *uvc = video_get_drvdata(vdev);
665 
666 	return uvcg_queue_get_unmapped_area(&uvc->video.queue, pgoff);
667 }
668 #endif
669 
670 const struct v4l2_file_operations uvc_v4l2_fops = {
671 	.owner		= THIS_MODULE,
672 	.open		= uvc_v4l2_open,
673 	.release	= uvc_v4l2_release,
674 	.unlocked_ioctl	= video_ioctl2,
675 	.mmap		= uvc_v4l2_mmap,
676 	.poll		= uvc_v4l2_poll,
677 #ifndef CONFIG_MMU
678 	.get_unmapped_area = uvcg_v4l2_get_unmapped_area,
679 #endif
680 };
681