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