1 /*
2  *	uvc_gadget.c  --  USB Video Class Gadget driver
3  *
4  *	Copyright (C) 2009-2010
5  *	    Laurent Pinchart (laurent.pinchart@ideasonboard.com)
6  *
7  *	This program is free software; you can redistribute it and/or modify
8  *	it under the terms of the GNU General Public License as published by
9  *	the Free Software Foundation; either version 2 of the License, or
10  *	(at your option) any later version.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/device.h>
16 #include <linux/errno.h>
17 #include <linux/fs.h>
18 #include <linux/list.h>
19 #include <linux/mutex.h>
20 #include <linux/string.h>
21 #include <linux/usb/ch9.h>
22 #include <linux/usb/gadget.h>
23 #include <linux/usb/video.h>
24 #include <linux/vmalloc.h>
25 #include <linux/wait.h>
26 
27 #include <media/v4l2-dev.h>
28 #include <media/v4l2-event.h>
29 
30 #include "uvc.h"
31 #include "uvc_v4l2.h"
32 #include "uvc_video.h"
33 #include "u_uvc.h"
34 
35 unsigned int uvc_gadget_trace_param;
36 
37 /* --------------------------------------------------------------------------
38  * Function descriptors
39  */
40 
41 /* string IDs are assigned dynamically */
42 
43 #define UVC_STRING_CONTROL_IDX			0
44 #define UVC_STRING_STREAMING_IDX		1
45 
46 static struct usb_string uvc_en_us_strings[] = {
47 	[UVC_STRING_CONTROL_IDX].s = "UVC Camera",
48 	[UVC_STRING_STREAMING_IDX].s = "Video Streaming",
49 	{  }
50 };
51 
52 static struct usb_gadget_strings uvc_stringtab = {
53 	.language = 0x0409,	/* en-us */
54 	.strings = uvc_en_us_strings,
55 };
56 
57 static struct usb_gadget_strings *uvc_function_strings[] = {
58 	&uvc_stringtab,
59 	NULL,
60 };
61 
62 #define UVC_INTF_VIDEO_CONTROL			0
63 #define UVC_INTF_VIDEO_STREAMING		1
64 
65 #define UVC_STATUS_MAX_PACKET_SIZE		16	/* 16 bytes status */
66 
67 static struct usb_interface_assoc_descriptor uvc_iad = {
68 	.bLength		= sizeof(uvc_iad),
69 	.bDescriptorType	= USB_DT_INTERFACE_ASSOCIATION,
70 	.bFirstInterface	= 0,
71 	.bInterfaceCount	= 2,
72 	.bFunctionClass		= USB_CLASS_VIDEO,
73 	.bFunctionSubClass	= UVC_SC_VIDEO_INTERFACE_COLLECTION,
74 	.bFunctionProtocol	= 0x00,
75 	.iFunction		= 0,
76 };
77 
78 static struct usb_interface_descriptor uvc_control_intf = {
79 	.bLength		= USB_DT_INTERFACE_SIZE,
80 	.bDescriptorType	= USB_DT_INTERFACE,
81 	.bInterfaceNumber	= UVC_INTF_VIDEO_CONTROL,
82 	.bAlternateSetting	= 0,
83 	.bNumEndpoints		= 1,
84 	.bInterfaceClass	= USB_CLASS_VIDEO,
85 	.bInterfaceSubClass	= UVC_SC_VIDEOCONTROL,
86 	.bInterfaceProtocol	= 0x00,
87 	.iInterface		= 0,
88 };
89 
90 static struct usb_endpoint_descriptor uvc_control_ep = {
91 	.bLength		= USB_DT_ENDPOINT_SIZE,
92 	.bDescriptorType	= USB_DT_ENDPOINT,
93 	.bEndpointAddress	= USB_DIR_IN,
94 	.bmAttributes		= USB_ENDPOINT_XFER_INT,
95 	.wMaxPacketSize		= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
96 	.bInterval		= 8,
97 };
98 
99 static struct usb_ss_ep_comp_descriptor uvc_ss_control_comp = {
100 	.bLength		= sizeof(uvc_ss_control_comp),
101 	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
102 	/* The following 3 values can be tweaked if necessary. */
103 	.bMaxBurst		= 0,
104 	.bmAttributes		= 0,
105 	.wBytesPerInterval	= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
106 };
107 
108 static struct uvc_control_endpoint_descriptor uvc_control_cs_ep = {
109 	.bLength		= UVC_DT_CONTROL_ENDPOINT_SIZE,
110 	.bDescriptorType	= USB_DT_CS_ENDPOINT,
111 	.bDescriptorSubType	= UVC_EP_INTERRUPT,
112 	.wMaxTransferSize	= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
113 };
114 
115 static struct usb_interface_descriptor uvc_streaming_intf_alt0 = {
116 	.bLength		= USB_DT_INTERFACE_SIZE,
117 	.bDescriptorType	= USB_DT_INTERFACE,
118 	.bInterfaceNumber	= UVC_INTF_VIDEO_STREAMING,
119 	.bAlternateSetting	= 0,
120 	.bNumEndpoints		= 0,
121 	.bInterfaceClass	= USB_CLASS_VIDEO,
122 	.bInterfaceSubClass	= UVC_SC_VIDEOSTREAMING,
123 	.bInterfaceProtocol	= 0x00,
124 	.iInterface		= 0,
125 };
126 
127 static struct usb_interface_descriptor uvc_streaming_intf_alt1 = {
128 	.bLength		= USB_DT_INTERFACE_SIZE,
129 	.bDescriptorType	= USB_DT_INTERFACE,
130 	.bInterfaceNumber	= UVC_INTF_VIDEO_STREAMING,
131 	.bAlternateSetting	= 1,
132 	.bNumEndpoints		= 1,
133 	.bInterfaceClass	= USB_CLASS_VIDEO,
134 	.bInterfaceSubClass	= UVC_SC_VIDEOSTREAMING,
135 	.bInterfaceProtocol	= 0x00,
136 	.iInterface		= 0,
137 };
138 
139 static struct usb_endpoint_descriptor uvc_fs_streaming_ep = {
140 	.bLength		= USB_DT_ENDPOINT_SIZE,
141 	.bDescriptorType	= USB_DT_ENDPOINT,
142 	.bEndpointAddress	= USB_DIR_IN,
143 	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
144 				| USB_ENDPOINT_XFER_ISOC,
145 	/* The wMaxPacketSize and bInterval values will be initialized from
146 	 * module parameters.
147 	 */
148 };
149 
150 static struct usb_endpoint_descriptor uvc_hs_streaming_ep = {
151 	.bLength		= USB_DT_ENDPOINT_SIZE,
152 	.bDescriptorType	= USB_DT_ENDPOINT,
153 	.bEndpointAddress	= USB_DIR_IN,
154 	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
155 				| USB_ENDPOINT_XFER_ISOC,
156 	/* The wMaxPacketSize and bInterval values will be initialized from
157 	 * module parameters.
158 	 */
159 };
160 
161 static struct usb_endpoint_descriptor uvc_ss_streaming_ep = {
162 	.bLength		= USB_DT_ENDPOINT_SIZE,
163 	.bDescriptorType	= USB_DT_ENDPOINT,
164 
165 	.bEndpointAddress	= USB_DIR_IN,
166 	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
167 				| USB_ENDPOINT_XFER_ISOC,
168 	/* The wMaxPacketSize and bInterval values will be initialized from
169 	 * module parameters.
170 	 */
171 };
172 
173 static struct usb_ss_ep_comp_descriptor uvc_ss_streaming_comp = {
174 	.bLength		= sizeof(uvc_ss_streaming_comp),
175 	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
176 	/* The bMaxBurst, bmAttributes and wBytesPerInterval values will be
177 	 * initialized from module parameters.
178 	 */
179 };
180 
181 static const struct usb_descriptor_header * const uvc_fs_streaming[] = {
182 	(struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
183 	(struct usb_descriptor_header *) &uvc_fs_streaming_ep,
184 	NULL,
185 };
186 
187 static const struct usb_descriptor_header * const uvc_hs_streaming[] = {
188 	(struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
189 	(struct usb_descriptor_header *) &uvc_hs_streaming_ep,
190 	NULL,
191 };
192 
193 static const struct usb_descriptor_header * const uvc_ss_streaming[] = {
194 	(struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
195 	(struct usb_descriptor_header *) &uvc_ss_streaming_ep,
196 	(struct usb_descriptor_header *) &uvc_ss_streaming_comp,
197 	NULL,
198 };
199 
200 void uvc_set_trace_param(unsigned int trace)
201 {
202 	uvc_gadget_trace_param = trace;
203 }
204 EXPORT_SYMBOL(uvc_set_trace_param);
205 
206 /* --------------------------------------------------------------------------
207  * Control requests
208  */
209 
210 static void
211 uvc_function_ep0_complete(struct usb_ep *ep, struct usb_request *req)
212 {
213 	struct uvc_device *uvc = req->context;
214 	struct v4l2_event v4l2_event;
215 	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
216 
217 	if (uvc->event_setup_out) {
218 		uvc->event_setup_out = 0;
219 
220 		memset(&v4l2_event, 0, sizeof(v4l2_event));
221 		v4l2_event.type = UVC_EVENT_DATA;
222 		uvc_event->data.length = req->actual;
223 		memcpy(&uvc_event->data.data, req->buf, req->actual);
224 		v4l2_event_queue(uvc->vdev, &v4l2_event);
225 	}
226 }
227 
228 static int
229 uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
230 {
231 	struct uvc_device *uvc = to_uvc(f);
232 	struct v4l2_event v4l2_event;
233 	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
234 
235 	/* printk(KERN_INFO "setup request %02x %02x value %04x index %04x %04x\n",
236 	 *	ctrl->bRequestType, ctrl->bRequest, le16_to_cpu(ctrl->wValue),
237 	 *	le16_to_cpu(ctrl->wIndex), le16_to_cpu(ctrl->wLength));
238 	 */
239 
240 	if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) {
241 		INFO(f->config->cdev, "invalid request type\n");
242 		return -EINVAL;
243 	}
244 
245 	/* Stall too big requests. */
246 	if (le16_to_cpu(ctrl->wLength) > UVC_MAX_REQUEST_SIZE)
247 		return -EINVAL;
248 
249 	/* Tell the complete callback to generate an event for the next request
250 	 * that will be enqueued by UVCIOC_SEND_RESPONSE.
251 	 */
252 	uvc->event_setup_out = !(ctrl->bRequestType & USB_DIR_IN);
253 	uvc->event_length = le16_to_cpu(ctrl->wLength);
254 
255 	memset(&v4l2_event, 0, sizeof(v4l2_event));
256 	v4l2_event.type = UVC_EVENT_SETUP;
257 	memcpy(&uvc_event->req, ctrl, sizeof(uvc_event->req));
258 	v4l2_event_queue(uvc->vdev, &v4l2_event);
259 
260 	return 0;
261 }
262 
263 void uvc_function_setup_continue(struct uvc_device *uvc)
264 {
265 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
266 
267 	usb_composite_setup_continue(cdev);
268 }
269 
270 static int
271 uvc_function_get_alt(struct usb_function *f, unsigned interface)
272 {
273 	struct uvc_device *uvc = to_uvc(f);
274 
275 	INFO(f->config->cdev, "uvc_function_get_alt(%u)\n", interface);
276 
277 	if (interface == uvc->control_intf)
278 		return 0;
279 	else if (interface != uvc->streaming_intf)
280 		return -EINVAL;
281 	else
282 		return uvc->state == UVC_STATE_STREAMING ? 1 : 0;
283 }
284 
285 static int
286 uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
287 {
288 	struct uvc_device *uvc = to_uvc(f);
289 	struct v4l2_event v4l2_event;
290 	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
291 	int ret;
292 
293 	INFO(f->config->cdev, "uvc_function_set_alt(%u, %u)\n", interface, alt);
294 
295 	if (interface == uvc->control_intf) {
296 		if (alt)
297 			return -EINVAL;
298 
299 		if (uvc->state == UVC_STATE_DISCONNECTED) {
300 			memset(&v4l2_event, 0, sizeof(v4l2_event));
301 			v4l2_event.type = UVC_EVENT_CONNECT;
302 			uvc_event->speed = f->config->cdev->gadget->speed;
303 			v4l2_event_queue(uvc->vdev, &v4l2_event);
304 
305 			uvc->state = UVC_STATE_CONNECTED;
306 		}
307 
308 		return 0;
309 	}
310 
311 	if (interface != uvc->streaming_intf)
312 		return -EINVAL;
313 
314 	/* TODO
315 	if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
316 		return alt ? -EINVAL : 0;
317 	*/
318 
319 	switch (alt) {
320 	case 0:
321 		if (uvc->state != UVC_STATE_STREAMING)
322 			return 0;
323 
324 		if (uvc->video.ep)
325 			usb_ep_disable(uvc->video.ep);
326 
327 		memset(&v4l2_event, 0, sizeof(v4l2_event));
328 		v4l2_event.type = UVC_EVENT_STREAMOFF;
329 		v4l2_event_queue(uvc->vdev, &v4l2_event);
330 
331 		uvc->state = UVC_STATE_CONNECTED;
332 		return 0;
333 
334 	case 1:
335 		if (uvc->state != UVC_STATE_CONNECTED)
336 			return 0;
337 
338 		if (uvc->video.ep) {
339 			ret = config_ep_by_speed(f->config->cdev->gadget,
340 					&(uvc->func), uvc->video.ep);
341 			if (ret)
342 				return ret;
343 			usb_ep_enable(uvc->video.ep);
344 		}
345 
346 		memset(&v4l2_event, 0, sizeof(v4l2_event));
347 		v4l2_event.type = UVC_EVENT_STREAMON;
348 		v4l2_event_queue(uvc->vdev, &v4l2_event);
349 		return USB_GADGET_DELAYED_STATUS;
350 
351 	default:
352 		return -EINVAL;
353 	}
354 }
355 
356 static void
357 uvc_function_disable(struct usb_function *f)
358 {
359 	struct uvc_device *uvc = to_uvc(f);
360 	struct v4l2_event v4l2_event;
361 
362 	INFO(f->config->cdev, "uvc_function_disable\n");
363 
364 	memset(&v4l2_event, 0, sizeof(v4l2_event));
365 	v4l2_event.type = UVC_EVENT_DISCONNECT;
366 	v4l2_event_queue(uvc->vdev, &v4l2_event);
367 
368 	uvc->state = UVC_STATE_DISCONNECTED;
369 }
370 
371 /* --------------------------------------------------------------------------
372  * Connection / disconnection
373  */
374 
375 void
376 uvc_function_connect(struct uvc_device *uvc)
377 {
378 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
379 	int ret;
380 
381 	if ((ret = usb_function_activate(&uvc->func)) < 0)
382 		INFO(cdev, "UVC connect failed with %d\n", ret);
383 }
384 
385 void
386 uvc_function_disconnect(struct uvc_device *uvc)
387 {
388 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
389 	int ret;
390 
391 	if ((ret = usb_function_deactivate(&uvc->func)) < 0)
392 		INFO(cdev, "UVC disconnect failed with %d\n", ret);
393 }
394 
395 /* --------------------------------------------------------------------------
396  * USB probe and disconnect
397  */
398 
399 static int
400 uvc_register_video(struct uvc_device *uvc)
401 {
402 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
403 	struct video_device *video;
404 
405 	/* TODO reference counting. */
406 	video = video_device_alloc();
407 	if (video == NULL)
408 		return -ENOMEM;
409 
410 	video->v4l2_dev = &uvc->v4l2_dev;
411 	video->fops = &uvc_v4l2_fops;
412 	video->ioctl_ops = &uvc_v4l2_ioctl_ops;
413 	video->release = video_device_release;
414 	video->vfl_dir = VFL_DIR_TX;
415 	strlcpy(video->name, cdev->gadget->name, sizeof(video->name));
416 
417 	uvc->vdev = video;
418 	video_set_drvdata(video, uvc);
419 
420 	return video_register_device(video, VFL_TYPE_GRABBER, -1);
421 }
422 
423 #define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
424 	do { \
425 		memcpy(mem, desc, (desc)->bLength); \
426 		*(dst)++ = mem; \
427 		mem += (desc)->bLength; \
428 	} while (0);
429 
430 #define UVC_COPY_DESCRIPTORS(mem, dst, src) \
431 	do { \
432 		const struct usb_descriptor_header * const *__src; \
433 		for (__src = src; *__src; ++__src) { \
434 			memcpy(mem, *__src, (*__src)->bLength); \
435 			*dst++ = mem; \
436 			mem += (*__src)->bLength; \
437 		} \
438 	} while (0)
439 
440 static struct usb_descriptor_header **
441 uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
442 {
443 	struct uvc_input_header_descriptor *uvc_streaming_header;
444 	struct uvc_header_descriptor *uvc_control_header;
445 	const struct uvc_descriptor_header * const *uvc_control_desc;
446 	const struct uvc_descriptor_header * const *uvc_streaming_cls;
447 	const struct usb_descriptor_header * const *uvc_streaming_std;
448 	const struct usb_descriptor_header * const *src;
449 	struct usb_descriptor_header **dst;
450 	struct usb_descriptor_header **hdr;
451 	unsigned int control_size;
452 	unsigned int streaming_size;
453 	unsigned int n_desc;
454 	unsigned int bytes;
455 	void *mem;
456 
457 	switch (speed) {
458 	case USB_SPEED_SUPER:
459 		uvc_control_desc = uvc->desc.ss_control;
460 		uvc_streaming_cls = uvc->desc.ss_streaming;
461 		uvc_streaming_std = uvc_ss_streaming;
462 		break;
463 
464 	case USB_SPEED_HIGH:
465 		uvc_control_desc = uvc->desc.fs_control;
466 		uvc_streaming_cls = uvc->desc.hs_streaming;
467 		uvc_streaming_std = uvc_hs_streaming;
468 		break;
469 
470 	case USB_SPEED_FULL:
471 	default:
472 		uvc_control_desc = uvc->desc.fs_control;
473 		uvc_streaming_cls = uvc->desc.fs_streaming;
474 		uvc_streaming_std = uvc_fs_streaming;
475 		break;
476 	}
477 
478 	/* Descriptors layout
479 	 *
480 	 * uvc_iad
481 	 * uvc_control_intf
482 	 * Class-specific UVC control descriptors
483 	 * uvc_control_ep
484 	 * uvc_control_cs_ep
485 	 * uvc_ss_control_comp (for SS only)
486 	 * uvc_streaming_intf_alt0
487 	 * Class-specific UVC streaming descriptors
488 	 * uvc_{fs|hs}_streaming
489 	 */
490 
491 	/* Count descriptors and compute their size. */
492 	control_size = 0;
493 	streaming_size = 0;
494 	bytes = uvc_iad.bLength + uvc_control_intf.bLength
495 	      + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
496 	      + uvc_streaming_intf_alt0.bLength;
497 
498 	if (speed == USB_SPEED_SUPER) {
499 		bytes += uvc_ss_control_comp.bLength;
500 		n_desc = 6;
501 	} else {
502 		n_desc = 5;
503 	}
504 
505 	for (src = (const struct usb_descriptor_header **)uvc_control_desc;
506 	     *src; ++src) {
507 		control_size += (*src)->bLength;
508 		bytes += (*src)->bLength;
509 		n_desc++;
510 	}
511 	for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
512 	     *src; ++src) {
513 		streaming_size += (*src)->bLength;
514 		bytes += (*src)->bLength;
515 		n_desc++;
516 	}
517 	for (src = uvc_streaming_std; *src; ++src) {
518 		bytes += (*src)->bLength;
519 		n_desc++;
520 	}
521 
522 	mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
523 	if (mem == NULL)
524 		return NULL;
525 
526 	hdr = mem;
527 	dst = mem;
528 	mem += (n_desc + 1) * sizeof(*src);
529 
530 	/* Copy the descriptors. */
531 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
532 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
533 
534 	uvc_control_header = mem;
535 	UVC_COPY_DESCRIPTORS(mem, dst,
536 		(const struct usb_descriptor_header **)uvc_control_desc);
537 	uvc_control_header->wTotalLength = cpu_to_le16(control_size);
538 	uvc_control_header->bInCollection = 1;
539 	uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
540 
541 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
542 	if (speed == USB_SPEED_SUPER)
543 		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
544 
545 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
546 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
547 
548 	uvc_streaming_header = mem;
549 	UVC_COPY_DESCRIPTORS(mem, dst,
550 		(const struct usb_descriptor_header**)uvc_streaming_cls);
551 	uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
552 	uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
553 
554 	UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
555 
556 	*dst = NULL;
557 	return hdr;
558 }
559 
560 static int
561 uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
562 {
563 	struct usb_composite_dev *cdev = c->cdev;
564 	struct uvc_device *uvc = to_uvc(f);
565 	struct usb_string *us;
566 	unsigned int max_packet_mult;
567 	unsigned int max_packet_size;
568 	struct usb_ep *ep;
569 	struct f_uvc_opts *opts;
570 	int ret = -EINVAL;
571 
572 	INFO(cdev, "uvc_function_bind\n");
573 
574 	opts = to_f_uvc_opts(f->fi);
575 	/* Sanity check the streaming endpoint module parameters.
576 	 */
577 	opts->streaming_interval = clamp(opts->streaming_interval, 1U, 16U);
578 	opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U);
579 	opts->streaming_maxburst = min(opts->streaming_maxburst, 15U);
580 
581 	/* Fill in the FS/HS/SS Video Streaming specific descriptors from the
582 	 * module parameters.
583 	 *
584 	 * NOTE: We assume that the user knows what they are doing and won't
585 	 * give parameters that their UDC doesn't support.
586 	 */
587 	if (opts->streaming_maxpacket <= 1024) {
588 		max_packet_mult = 1;
589 		max_packet_size = opts->streaming_maxpacket;
590 	} else if (opts->streaming_maxpacket <= 2048) {
591 		max_packet_mult = 2;
592 		max_packet_size = opts->streaming_maxpacket / 2;
593 	} else {
594 		max_packet_mult = 3;
595 		max_packet_size = opts->streaming_maxpacket / 3;
596 	}
597 
598 	uvc_fs_streaming_ep.wMaxPacketSize =
599 		cpu_to_le16(min(opts->streaming_maxpacket, 1023U));
600 	uvc_fs_streaming_ep.bInterval = opts->streaming_interval;
601 
602 	uvc_hs_streaming_ep.wMaxPacketSize =
603 		cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));
604 	uvc_hs_streaming_ep.bInterval = opts->streaming_interval;
605 
606 	uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);
607 	uvc_ss_streaming_ep.bInterval = opts->streaming_interval;
608 	uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
609 	uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
610 	uvc_ss_streaming_comp.wBytesPerInterval =
611 		cpu_to_le16(max_packet_size * max_packet_mult *
612 			    opts->streaming_maxburst);
613 
614 	/* Allocate endpoints. */
615 	ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);
616 	if (!ep) {
617 		INFO(cdev, "Unable to allocate control EP\n");
618 		goto error;
619 	}
620 	uvc->control_ep = ep;
621 	ep->driver_data = uvc;
622 
623 	if (gadget_is_superspeed(c->cdev->gadget))
624 		ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
625 					  &uvc_ss_streaming_comp);
626 	else if (gadget_is_dualspeed(cdev->gadget))
627 		ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
628 	else
629 		ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
630 
631 	if (!ep) {
632 		INFO(cdev, "Unable to allocate streaming EP\n");
633 		goto error;
634 	}
635 	uvc->video.ep = ep;
636 	ep->driver_data = uvc;
637 
638 	uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
639 	uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
640 	uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
641 
642 	us = usb_gstrings_attach(cdev, uvc_function_strings,
643 				 ARRAY_SIZE(uvc_en_us_strings));
644 	if (IS_ERR(us)) {
645 		ret = PTR_ERR(us);
646 		goto error;
647 	}
648 	uvc_iad.iFunction = us[UVC_STRING_CONTROL_IDX].id;
649 	uvc_control_intf.iInterface = us[UVC_STRING_CONTROL_IDX].id;
650 	ret = us[UVC_STRING_STREAMING_IDX].id;
651 	uvc_streaming_intf_alt0.iInterface = ret;
652 	uvc_streaming_intf_alt1.iInterface = ret;
653 
654 	/* Allocate interface IDs. */
655 	if ((ret = usb_interface_id(c, f)) < 0)
656 		goto error;
657 	uvc_iad.bFirstInterface = ret;
658 	uvc_control_intf.bInterfaceNumber = ret;
659 	uvc->control_intf = ret;
660 
661 	if ((ret = usb_interface_id(c, f)) < 0)
662 		goto error;
663 	uvc_streaming_intf_alt0.bInterfaceNumber = ret;
664 	uvc_streaming_intf_alt1.bInterfaceNumber = ret;
665 	uvc->streaming_intf = ret;
666 
667 	/* Copy descriptors */
668 	f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
669 	if (gadget_is_dualspeed(cdev->gadget))
670 		f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
671 	if (gadget_is_superspeed(c->cdev->gadget))
672 		f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
673 
674 	/* Preallocate control endpoint request. */
675 	uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
676 	uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
677 	if (uvc->control_req == NULL || uvc->control_buf == NULL) {
678 		ret = -ENOMEM;
679 		goto error;
680 	}
681 
682 	uvc->control_req->buf = uvc->control_buf;
683 	uvc->control_req->complete = uvc_function_ep0_complete;
684 	uvc->control_req->context = uvc;
685 
686 	/* Avoid letting this gadget enumerate until the userspace server is
687 	 * active.
688 	 */
689 	if ((ret = usb_function_deactivate(f)) < 0)
690 		goto error;
691 
692 	if (v4l2_device_register(&cdev->gadget->dev, &uvc->v4l2_dev)) {
693 		printk(KERN_INFO "v4l2_device_register failed\n");
694 		goto error;
695 	}
696 
697 	/* Initialise video. */
698 	ret = uvcg_video_init(&uvc->video);
699 	if (ret < 0)
700 		goto error;
701 
702 	/* Register a V4L2 device. */
703 	ret = uvc_register_video(uvc);
704 	if (ret < 0) {
705 		printk(KERN_INFO "Unable to register video device\n");
706 		goto error;
707 	}
708 
709 	return 0;
710 
711 error:
712 	v4l2_device_unregister(&uvc->v4l2_dev);
713 	if (uvc->vdev)
714 		video_device_release(uvc->vdev);
715 
716 	if (uvc->control_ep)
717 		uvc->control_ep->driver_data = NULL;
718 	if (uvc->video.ep)
719 		uvc->video.ep->driver_data = NULL;
720 
721 	if (uvc->control_req)
722 		usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
723 	kfree(uvc->control_buf);
724 
725 	usb_free_all_descriptors(f);
726 	return ret;
727 }
728 
729 /* --------------------------------------------------------------------------
730  * USB gadget function
731  */
732 
733 static void uvc_free_inst(struct usb_function_instance *f)
734 {
735 	struct f_uvc_opts *opts = to_f_uvc_opts(f);
736 
737 	kfree(opts);
738 }
739 
740 static struct usb_function_instance *uvc_alloc_inst(void)
741 {
742 	struct f_uvc_opts *opts;
743 
744 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
745 	if (!opts)
746 		return ERR_PTR(-ENOMEM);
747 	opts->func_inst.free_func_inst = uvc_free_inst;
748 
749 	return &opts->func_inst;
750 }
751 
752 static void uvc_free(struct usb_function *f)
753 {
754 	struct uvc_device *uvc = to_uvc(f);
755 
756 	kfree(uvc);
757 }
758 
759 static void uvc_unbind(struct usb_configuration *c, struct usb_function *f)
760 {
761 	struct usb_composite_dev *cdev = c->cdev;
762 	struct uvc_device *uvc = to_uvc(f);
763 
764 	INFO(cdev, "%s\n", __func__);
765 
766 	video_unregister_device(uvc->vdev);
767 	v4l2_device_unregister(&uvc->v4l2_dev);
768 	uvc->control_ep->driver_data = NULL;
769 	uvc->video.ep->driver_data = NULL;
770 
771 	usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
772 	kfree(uvc->control_buf);
773 
774 	usb_free_all_descriptors(f);
775 }
776 
777 static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
778 {
779 	struct uvc_device *uvc;
780 	struct f_uvc_opts *opts;
781 
782 	uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
783 	if (uvc == NULL)
784 		return ERR_PTR(-ENOMEM);
785 
786 	uvc->state = UVC_STATE_DISCONNECTED;
787 	opts = to_f_uvc_opts(fi);
788 
789 	uvc->desc.fs_control = opts->fs_control;
790 	uvc->desc.ss_control = opts->ss_control;
791 	uvc->desc.fs_streaming = opts->fs_streaming;
792 	uvc->desc.hs_streaming = opts->hs_streaming;
793 	uvc->desc.ss_streaming = opts->ss_streaming;
794 
795 	/* Register the function. */
796 	uvc->func.name = "uvc";
797 	uvc->func.bind = uvc_function_bind;
798 	uvc->func.unbind = uvc_unbind;
799 	uvc->func.get_alt = uvc_function_get_alt;
800 	uvc->func.set_alt = uvc_function_set_alt;
801 	uvc->func.disable = uvc_function_disable;
802 	uvc->func.setup = uvc_function_setup;
803 	uvc->func.free_func = uvc_free;
804 
805 	return &uvc->func;
806 }
807 
808 DECLARE_USB_FUNCTION_INIT(uvc, uvc_alloc_inst, uvc_alloc);
809 MODULE_LICENSE("GPL");
810 MODULE_AUTHOR("Laurent Pinchart");
811