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 "u_uvc.h"
31 #include "uvc.h"
32 #include "uvc_configfs.h"
33 #include "uvc_v4l2.h"
34 #include "uvc_video.h"
35 
36 unsigned int uvc_gadget_trace_param;
37 
38 /* --------------------------------------------------------------------------
39  * Function descriptors
40  */
41 
42 /* string IDs are assigned dynamically */
43 
44 #define UVC_STRING_CONTROL_IDX			0
45 #define UVC_STRING_STREAMING_IDX		1
46 
47 static struct usb_string uvc_en_us_strings[] = {
48 	[UVC_STRING_CONTROL_IDX].s = "UVC Camera",
49 	[UVC_STRING_STREAMING_IDX].s = "Video Streaming",
50 	{  }
51 };
52 
53 static struct usb_gadget_strings uvc_stringtab = {
54 	.language = 0x0409,	/* en-us */
55 	.strings = uvc_en_us_strings,
56 };
57 
58 static struct usb_gadget_strings *uvc_function_strings[] = {
59 	&uvc_stringtab,
60 	NULL,
61 };
62 
63 #define UVC_INTF_VIDEO_CONTROL			0
64 #define UVC_INTF_VIDEO_STREAMING		1
65 
66 #define UVC_STATUS_MAX_PACKET_SIZE		16	/* 16 bytes status */
67 
68 static struct usb_interface_assoc_descriptor uvc_iad = {
69 	.bLength		= sizeof(uvc_iad),
70 	.bDescriptorType	= USB_DT_INTERFACE_ASSOCIATION,
71 	.bFirstInterface	= 0,
72 	.bInterfaceCount	= 2,
73 	.bFunctionClass		= USB_CLASS_VIDEO,
74 	.bFunctionSubClass	= UVC_SC_VIDEO_INTERFACE_COLLECTION,
75 	.bFunctionProtocol	= 0x00,
76 	.iFunction		= 0,
77 };
78 
79 static struct usb_interface_descriptor uvc_control_intf = {
80 	.bLength		= USB_DT_INTERFACE_SIZE,
81 	.bDescriptorType	= USB_DT_INTERFACE,
82 	.bInterfaceNumber	= UVC_INTF_VIDEO_CONTROL,
83 	.bAlternateSetting	= 0,
84 	.bNumEndpoints		= 1,
85 	.bInterfaceClass	= USB_CLASS_VIDEO,
86 	.bInterfaceSubClass	= UVC_SC_VIDEOCONTROL,
87 	.bInterfaceProtocol	= 0x00,
88 	.iInterface		= 0,
89 };
90 
91 static struct usb_endpoint_descriptor uvc_control_ep = {
92 	.bLength		= USB_DT_ENDPOINT_SIZE,
93 	.bDescriptorType	= USB_DT_ENDPOINT,
94 	.bEndpointAddress	= USB_DIR_IN,
95 	.bmAttributes		= USB_ENDPOINT_XFER_INT,
96 	.wMaxPacketSize		= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
97 	.bInterval		= 8,
98 };
99 
100 static struct usb_ss_ep_comp_descriptor uvc_ss_control_comp = {
101 	.bLength		= sizeof(uvc_ss_control_comp),
102 	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
103 	/* The following 3 values can be tweaked if necessary. */
104 	.bMaxBurst		= 0,
105 	.bmAttributes		= 0,
106 	.wBytesPerInterval	= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
107 };
108 
109 static struct uvc_control_endpoint_descriptor uvc_control_cs_ep = {
110 	.bLength		= UVC_DT_CONTROL_ENDPOINT_SIZE,
111 	.bDescriptorType	= USB_DT_CS_ENDPOINT,
112 	.bDescriptorSubType	= UVC_EP_INTERRUPT,
113 	.wMaxTransferSize	= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
114 };
115 
116 static struct usb_interface_descriptor uvc_streaming_intf_alt0 = {
117 	.bLength		= USB_DT_INTERFACE_SIZE,
118 	.bDescriptorType	= USB_DT_INTERFACE,
119 	.bInterfaceNumber	= UVC_INTF_VIDEO_STREAMING,
120 	.bAlternateSetting	= 0,
121 	.bNumEndpoints		= 0,
122 	.bInterfaceClass	= USB_CLASS_VIDEO,
123 	.bInterfaceSubClass	= UVC_SC_VIDEOSTREAMING,
124 	.bInterfaceProtocol	= 0x00,
125 	.iInterface		= 0,
126 };
127 
128 static struct usb_interface_descriptor uvc_streaming_intf_alt1 = {
129 	.bLength		= USB_DT_INTERFACE_SIZE,
130 	.bDescriptorType	= USB_DT_INTERFACE,
131 	.bInterfaceNumber	= UVC_INTF_VIDEO_STREAMING,
132 	.bAlternateSetting	= 1,
133 	.bNumEndpoints		= 1,
134 	.bInterfaceClass	= USB_CLASS_VIDEO,
135 	.bInterfaceSubClass	= UVC_SC_VIDEOSTREAMING,
136 	.bInterfaceProtocol	= 0x00,
137 	.iInterface		= 0,
138 };
139 
140 static struct usb_endpoint_descriptor uvc_fs_streaming_ep = {
141 	.bLength		= USB_DT_ENDPOINT_SIZE,
142 	.bDescriptorType	= USB_DT_ENDPOINT,
143 	.bEndpointAddress	= USB_DIR_IN,
144 	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
145 				| USB_ENDPOINT_XFER_ISOC,
146 	/* The wMaxPacketSize and bInterval values will be initialized from
147 	 * module parameters.
148 	 */
149 };
150 
151 static struct usb_endpoint_descriptor uvc_hs_streaming_ep = {
152 	.bLength		= USB_DT_ENDPOINT_SIZE,
153 	.bDescriptorType	= USB_DT_ENDPOINT,
154 	.bEndpointAddress	= USB_DIR_IN,
155 	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
156 				| USB_ENDPOINT_XFER_ISOC,
157 	/* The wMaxPacketSize and bInterval values will be initialized from
158 	 * module parameters.
159 	 */
160 };
161 
162 static struct usb_endpoint_descriptor uvc_ss_streaming_ep = {
163 	.bLength		= USB_DT_ENDPOINT_SIZE,
164 	.bDescriptorType	= USB_DT_ENDPOINT,
165 
166 	.bEndpointAddress	= USB_DIR_IN,
167 	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
168 				| USB_ENDPOINT_XFER_ISOC,
169 	/* The wMaxPacketSize and bInterval values will be initialized from
170 	 * module parameters.
171 	 */
172 };
173 
174 static struct usb_ss_ep_comp_descriptor uvc_ss_streaming_comp = {
175 	.bLength		= sizeof(uvc_ss_streaming_comp),
176 	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
177 	/* The bMaxBurst, bmAttributes and wBytesPerInterval values will be
178 	 * initialized from module parameters.
179 	 */
180 };
181 
182 static const struct usb_descriptor_header * const uvc_fs_streaming[] = {
183 	(struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
184 	(struct usb_descriptor_header *) &uvc_fs_streaming_ep,
185 	NULL,
186 };
187 
188 static const struct usb_descriptor_header * const uvc_hs_streaming[] = {
189 	(struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
190 	(struct usb_descriptor_header *) &uvc_hs_streaming_ep,
191 	NULL,
192 };
193 
194 static const struct usb_descriptor_header * const uvc_ss_streaming[] = {
195 	(struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
196 	(struct usb_descriptor_header *) &uvc_ss_streaming_ep,
197 	(struct usb_descriptor_header *) &uvc_ss_streaming_comp,
198 	NULL,
199 };
200 
201 void uvc_set_trace_param(unsigned int trace)
202 {
203 	uvc_gadget_trace_param = trace;
204 }
205 EXPORT_SYMBOL(uvc_set_trace_param);
206 
207 /* --------------------------------------------------------------------------
208  * Control requests
209  */
210 
211 static void
212 uvc_function_ep0_complete(struct usb_ep *ep, struct usb_request *req)
213 {
214 	struct uvc_device *uvc = req->context;
215 	struct v4l2_event v4l2_event;
216 	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
217 
218 	if (uvc->event_setup_out) {
219 		uvc->event_setup_out = 0;
220 
221 		memset(&v4l2_event, 0, sizeof(v4l2_event));
222 		v4l2_event.type = UVC_EVENT_DATA;
223 		uvc_event->data.length = req->actual;
224 		memcpy(&uvc_event->data.data, req->buf, req->actual);
225 		v4l2_event_queue(&uvc->vdev, &v4l2_event);
226 	}
227 }
228 
229 static int
230 uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
231 {
232 	struct uvc_device *uvc = to_uvc(f);
233 	struct v4l2_event v4l2_event;
234 	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
235 
236 	/* printk(KERN_INFO "setup request %02x %02x value %04x index %04x %04x\n",
237 	 *	ctrl->bRequestType, ctrl->bRequest, le16_to_cpu(ctrl->wValue),
238 	 *	le16_to_cpu(ctrl->wIndex), le16_to_cpu(ctrl->wLength));
239 	 */
240 
241 	if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) {
242 		INFO(f->config->cdev, "invalid request type\n");
243 		return -EINVAL;
244 	}
245 
246 	/* Stall too big requests. */
247 	if (le16_to_cpu(ctrl->wLength) > UVC_MAX_REQUEST_SIZE)
248 		return -EINVAL;
249 
250 	/* Tell the complete callback to generate an event for the next request
251 	 * that will be enqueued by UVCIOC_SEND_RESPONSE.
252 	 */
253 	uvc->event_setup_out = !(ctrl->bRequestType & USB_DIR_IN);
254 	uvc->event_length = le16_to_cpu(ctrl->wLength);
255 
256 	memset(&v4l2_event, 0, sizeof(v4l2_event));
257 	v4l2_event.type = UVC_EVENT_SETUP;
258 	memcpy(&uvc_event->req, ctrl, sizeof(uvc_event->req));
259 	v4l2_event_queue(&uvc->vdev, &v4l2_event);
260 
261 	/* Pass additional setup data to userspace */
262 	if (uvc->event_setup_out && uvc->event_length) {
263 		uvc->control_req->length = uvc->event_length;
264 		return usb_ep_queue(uvc->func.config->cdev->gadget->ep0,
265 			uvc->control_req, GFP_ATOMIC);
266 	}
267 
268 	return 0;
269 }
270 
271 void uvc_function_setup_continue(struct uvc_device *uvc)
272 {
273 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
274 
275 	usb_composite_setup_continue(cdev);
276 }
277 
278 static int
279 uvc_function_get_alt(struct usb_function *f, unsigned interface)
280 {
281 	struct uvc_device *uvc = to_uvc(f);
282 
283 	INFO(f->config->cdev, "uvc_function_get_alt(%u)\n", interface);
284 
285 	if (interface == uvc->control_intf)
286 		return 0;
287 	else if (interface != uvc->streaming_intf)
288 		return -EINVAL;
289 	else
290 		return uvc->video.ep->enabled ? 1 : 0;
291 }
292 
293 static int
294 uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
295 {
296 	struct uvc_device *uvc = to_uvc(f);
297 	struct usb_composite_dev *cdev = f->config->cdev;
298 	struct v4l2_event v4l2_event;
299 	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
300 	int ret;
301 
302 	INFO(cdev, "uvc_function_set_alt(%u, %u)\n", interface, alt);
303 
304 	if (interface == uvc->control_intf) {
305 		if (alt)
306 			return -EINVAL;
307 
308 		INFO(cdev, "reset UVC Control\n");
309 		usb_ep_disable(uvc->control_ep);
310 
311 		if (!uvc->control_ep->desc)
312 			if (config_ep_by_speed(cdev->gadget, f, uvc->control_ep))
313 				return -EINVAL;
314 
315 		usb_ep_enable(uvc->control_ep);
316 
317 		if (uvc->state == UVC_STATE_DISCONNECTED) {
318 			memset(&v4l2_event, 0, sizeof(v4l2_event));
319 			v4l2_event.type = UVC_EVENT_CONNECT;
320 			uvc_event->speed = cdev->gadget->speed;
321 			v4l2_event_queue(&uvc->vdev, &v4l2_event);
322 
323 			uvc->state = UVC_STATE_CONNECTED;
324 		}
325 
326 		return 0;
327 	}
328 
329 	if (interface != uvc->streaming_intf)
330 		return -EINVAL;
331 
332 	/* TODO
333 	if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
334 		return alt ? -EINVAL : 0;
335 	*/
336 
337 	switch (alt) {
338 	case 0:
339 		if (uvc->state != UVC_STATE_STREAMING)
340 			return 0;
341 
342 		if (uvc->video.ep)
343 			usb_ep_disable(uvc->video.ep);
344 
345 		memset(&v4l2_event, 0, sizeof(v4l2_event));
346 		v4l2_event.type = UVC_EVENT_STREAMOFF;
347 		v4l2_event_queue(&uvc->vdev, &v4l2_event);
348 
349 		uvc->state = UVC_STATE_CONNECTED;
350 		return 0;
351 
352 	case 1:
353 		if (uvc->state != UVC_STATE_CONNECTED)
354 			return 0;
355 
356 		if (!uvc->video.ep)
357 			return -EINVAL;
358 
359 		INFO(cdev, "reset UVC\n");
360 		usb_ep_disable(uvc->video.ep);
361 
362 		ret = config_ep_by_speed(f->config->cdev->gadget,
363 				&(uvc->func), uvc->video.ep);
364 		if (ret)
365 			return ret;
366 		usb_ep_enable(uvc->video.ep);
367 
368 		memset(&v4l2_event, 0, sizeof(v4l2_event));
369 		v4l2_event.type = UVC_EVENT_STREAMON;
370 		v4l2_event_queue(&uvc->vdev, &v4l2_event);
371 		return USB_GADGET_DELAYED_STATUS;
372 
373 	default:
374 		return -EINVAL;
375 	}
376 }
377 
378 static void
379 uvc_function_disable(struct usb_function *f)
380 {
381 	struct uvc_device *uvc = to_uvc(f);
382 	struct v4l2_event v4l2_event;
383 
384 	INFO(f->config->cdev, "uvc_function_disable\n");
385 
386 	memset(&v4l2_event, 0, sizeof(v4l2_event));
387 	v4l2_event.type = UVC_EVENT_DISCONNECT;
388 	v4l2_event_queue(&uvc->vdev, &v4l2_event);
389 
390 	uvc->state = UVC_STATE_DISCONNECTED;
391 
392 	usb_ep_disable(uvc->video.ep);
393 	usb_ep_disable(uvc->control_ep);
394 }
395 
396 /* --------------------------------------------------------------------------
397  * Connection / disconnection
398  */
399 
400 void
401 uvc_function_connect(struct uvc_device *uvc)
402 {
403 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
404 	int ret;
405 
406 	if ((ret = usb_function_activate(&uvc->func)) < 0)
407 		INFO(cdev, "UVC connect failed with %d\n", ret);
408 }
409 
410 void
411 uvc_function_disconnect(struct uvc_device *uvc)
412 {
413 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
414 	int ret;
415 
416 	if ((ret = usb_function_deactivate(&uvc->func)) < 0)
417 		INFO(cdev, "UVC disconnect failed with %d\n", ret);
418 }
419 
420 /* --------------------------------------------------------------------------
421  * USB probe and disconnect
422  */
423 
424 static int
425 uvc_register_video(struct uvc_device *uvc)
426 {
427 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
428 
429 	/* TODO reference counting. */
430 	uvc->vdev.v4l2_dev = &uvc->v4l2_dev;
431 	uvc->vdev.fops = &uvc_v4l2_fops;
432 	uvc->vdev.ioctl_ops = &uvc_v4l2_ioctl_ops;
433 	uvc->vdev.release = video_device_release_empty;
434 	uvc->vdev.vfl_dir = VFL_DIR_TX;
435 	uvc->vdev.lock = &uvc->video.mutex;
436 	strlcpy(uvc->vdev.name, cdev->gadget->name, sizeof(uvc->vdev.name));
437 
438 	video_set_drvdata(&uvc->vdev, uvc);
439 
440 	return video_register_device(&uvc->vdev, VFL_TYPE_GRABBER, -1);
441 }
442 
443 #define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
444 	do { \
445 		memcpy(mem, desc, (desc)->bLength); \
446 		*(dst)++ = mem; \
447 		mem += (desc)->bLength; \
448 	} while (0);
449 
450 #define UVC_COPY_DESCRIPTORS(mem, dst, src) \
451 	do { \
452 		const struct usb_descriptor_header * const *__src; \
453 		for (__src = src; *__src; ++__src) { \
454 			memcpy(mem, *__src, (*__src)->bLength); \
455 			*dst++ = mem; \
456 			mem += (*__src)->bLength; \
457 		} \
458 	} while (0)
459 
460 static struct usb_descriptor_header **
461 uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
462 {
463 	struct uvc_input_header_descriptor *uvc_streaming_header;
464 	struct uvc_header_descriptor *uvc_control_header;
465 	const struct uvc_descriptor_header * const *uvc_control_desc;
466 	const struct uvc_descriptor_header * const *uvc_streaming_cls;
467 	const struct usb_descriptor_header * const *uvc_streaming_std;
468 	const struct usb_descriptor_header * const *src;
469 	struct usb_descriptor_header **dst;
470 	struct usb_descriptor_header **hdr;
471 	unsigned int control_size;
472 	unsigned int streaming_size;
473 	unsigned int n_desc;
474 	unsigned int bytes;
475 	void *mem;
476 
477 	switch (speed) {
478 	case USB_SPEED_SUPER:
479 		uvc_control_desc = uvc->desc.ss_control;
480 		uvc_streaming_cls = uvc->desc.ss_streaming;
481 		uvc_streaming_std = uvc_ss_streaming;
482 		break;
483 
484 	case USB_SPEED_HIGH:
485 		uvc_control_desc = uvc->desc.fs_control;
486 		uvc_streaming_cls = uvc->desc.hs_streaming;
487 		uvc_streaming_std = uvc_hs_streaming;
488 		break;
489 
490 	case USB_SPEED_FULL:
491 	default:
492 		uvc_control_desc = uvc->desc.fs_control;
493 		uvc_streaming_cls = uvc->desc.fs_streaming;
494 		uvc_streaming_std = uvc_fs_streaming;
495 		break;
496 	}
497 
498 	if (!uvc_control_desc || !uvc_streaming_cls)
499 		return ERR_PTR(-ENODEV);
500 
501 	/* Descriptors layout
502 	 *
503 	 * uvc_iad
504 	 * uvc_control_intf
505 	 * Class-specific UVC control descriptors
506 	 * uvc_control_ep
507 	 * uvc_control_cs_ep
508 	 * uvc_ss_control_comp (for SS only)
509 	 * uvc_streaming_intf_alt0
510 	 * Class-specific UVC streaming descriptors
511 	 * uvc_{fs|hs}_streaming
512 	 */
513 
514 	/* Count descriptors and compute their size. */
515 	control_size = 0;
516 	streaming_size = 0;
517 	bytes = uvc_iad.bLength + uvc_control_intf.bLength
518 	      + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
519 	      + uvc_streaming_intf_alt0.bLength;
520 
521 	if (speed == USB_SPEED_SUPER) {
522 		bytes += uvc_ss_control_comp.bLength;
523 		n_desc = 6;
524 	} else {
525 		n_desc = 5;
526 	}
527 
528 	for (src = (const struct usb_descriptor_header **)uvc_control_desc;
529 	     *src; ++src) {
530 		control_size += (*src)->bLength;
531 		bytes += (*src)->bLength;
532 		n_desc++;
533 	}
534 	for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
535 	     *src; ++src) {
536 		streaming_size += (*src)->bLength;
537 		bytes += (*src)->bLength;
538 		n_desc++;
539 	}
540 	for (src = uvc_streaming_std; *src; ++src) {
541 		bytes += (*src)->bLength;
542 		n_desc++;
543 	}
544 
545 	mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
546 	if (mem == NULL)
547 		return NULL;
548 
549 	hdr = mem;
550 	dst = mem;
551 	mem += (n_desc + 1) * sizeof(*src);
552 
553 	/* Copy the descriptors. */
554 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
555 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
556 
557 	uvc_control_header = mem;
558 	UVC_COPY_DESCRIPTORS(mem, dst,
559 		(const struct usb_descriptor_header **)uvc_control_desc);
560 	uvc_control_header->wTotalLength = cpu_to_le16(control_size);
561 	uvc_control_header->bInCollection = 1;
562 	uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
563 
564 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
565 	if (speed == USB_SPEED_SUPER)
566 		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
567 
568 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
569 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
570 
571 	uvc_streaming_header = mem;
572 	UVC_COPY_DESCRIPTORS(mem, dst,
573 		(const struct usb_descriptor_header**)uvc_streaming_cls);
574 	uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
575 	uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
576 
577 	UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
578 
579 	*dst = NULL;
580 	return hdr;
581 }
582 
583 static int
584 uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
585 {
586 	struct usb_composite_dev *cdev = c->cdev;
587 	struct uvc_device *uvc = to_uvc(f);
588 	struct usb_string *us;
589 	unsigned int max_packet_mult;
590 	unsigned int max_packet_size;
591 	struct usb_ep *ep;
592 	struct f_uvc_opts *opts;
593 	int ret = -EINVAL;
594 
595 	INFO(cdev, "uvc_function_bind\n");
596 
597 	opts = fi_to_f_uvc_opts(f->fi);
598 	/* Sanity check the streaming endpoint module parameters.
599 	 */
600 	opts->streaming_interval = clamp(opts->streaming_interval, 1U, 16U);
601 	opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U);
602 	opts->streaming_maxburst = min(opts->streaming_maxburst, 15U);
603 
604 	/* Fill in the FS/HS/SS Video Streaming specific descriptors from the
605 	 * module parameters.
606 	 *
607 	 * NOTE: We assume that the user knows what they are doing and won't
608 	 * give parameters that their UDC doesn't support.
609 	 */
610 	if (opts->streaming_maxpacket <= 1024) {
611 		max_packet_mult = 1;
612 		max_packet_size = opts->streaming_maxpacket;
613 	} else if (opts->streaming_maxpacket <= 2048) {
614 		max_packet_mult = 2;
615 		max_packet_size = opts->streaming_maxpacket / 2;
616 	} else {
617 		max_packet_mult = 3;
618 		max_packet_size = opts->streaming_maxpacket / 3;
619 	}
620 
621 	uvc_fs_streaming_ep.wMaxPacketSize =
622 		cpu_to_le16(min(opts->streaming_maxpacket, 1023U));
623 	uvc_fs_streaming_ep.bInterval = opts->streaming_interval;
624 
625 	uvc_hs_streaming_ep.wMaxPacketSize =
626 		cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));
627 	uvc_hs_streaming_ep.bInterval = opts->streaming_interval;
628 
629 	uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);
630 	uvc_ss_streaming_ep.bInterval = opts->streaming_interval;
631 	uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
632 	uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
633 	uvc_ss_streaming_comp.wBytesPerInterval =
634 		cpu_to_le16(max_packet_size * max_packet_mult *
635 			    opts->streaming_maxburst);
636 
637 	/* Allocate endpoints. */
638 	ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);
639 	if (!ep) {
640 		INFO(cdev, "Unable to allocate control EP\n");
641 		goto error;
642 	}
643 	uvc->control_ep = ep;
644 
645 	if (gadget_is_superspeed(c->cdev->gadget))
646 		ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
647 					  &uvc_ss_streaming_comp);
648 	else if (gadget_is_dualspeed(cdev->gadget))
649 		ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
650 	else
651 		ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
652 
653 	if (!ep) {
654 		INFO(cdev, "Unable to allocate streaming EP\n");
655 		goto error;
656 	}
657 	uvc->video.ep = ep;
658 
659 	uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
660 	uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
661 	uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
662 
663 	us = usb_gstrings_attach(cdev, uvc_function_strings,
664 				 ARRAY_SIZE(uvc_en_us_strings));
665 	if (IS_ERR(us)) {
666 		ret = PTR_ERR(us);
667 		goto error;
668 	}
669 	uvc_iad.iFunction = us[UVC_STRING_CONTROL_IDX].id;
670 	uvc_control_intf.iInterface = us[UVC_STRING_CONTROL_IDX].id;
671 	ret = us[UVC_STRING_STREAMING_IDX].id;
672 	uvc_streaming_intf_alt0.iInterface = ret;
673 	uvc_streaming_intf_alt1.iInterface = ret;
674 
675 	/* Allocate interface IDs. */
676 	if ((ret = usb_interface_id(c, f)) < 0)
677 		goto error;
678 	uvc_iad.bFirstInterface = ret;
679 	uvc_control_intf.bInterfaceNumber = ret;
680 	uvc->control_intf = ret;
681 
682 	if ((ret = usb_interface_id(c, f)) < 0)
683 		goto error;
684 	uvc_streaming_intf_alt0.bInterfaceNumber = ret;
685 	uvc_streaming_intf_alt1.bInterfaceNumber = ret;
686 	uvc->streaming_intf = ret;
687 
688 	/* Copy descriptors */
689 	f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
690 	if (IS_ERR(f->fs_descriptors)) {
691 		ret = PTR_ERR(f->fs_descriptors);
692 		f->fs_descriptors = NULL;
693 		goto error;
694 	}
695 	if (gadget_is_dualspeed(cdev->gadget)) {
696 		f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
697 		if (IS_ERR(f->hs_descriptors)) {
698 			ret = PTR_ERR(f->hs_descriptors);
699 			f->hs_descriptors = NULL;
700 			goto error;
701 		}
702 	}
703 	if (gadget_is_superspeed(c->cdev->gadget)) {
704 		f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
705 		if (IS_ERR(f->ss_descriptors)) {
706 			ret = PTR_ERR(f->ss_descriptors);
707 			f->ss_descriptors = NULL;
708 			goto error;
709 		}
710 	}
711 
712 	/* Preallocate control endpoint request. */
713 	uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
714 	uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
715 	if (uvc->control_req == NULL || uvc->control_buf == NULL) {
716 		ret = -ENOMEM;
717 		goto error;
718 	}
719 
720 	uvc->control_req->buf = uvc->control_buf;
721 	uvc->control_req->complete = uvc_function_ep0_complete;
722 	uvc->control_req->context = uvc;
723 
724 	if (v4l2_device_register(&cdev->gadget->dev, &uvc->v4l2_dev)) {
725 		printk(KERN_INFO "v4l2_device_register failed\n");
726 		goto error;
727 	}
728 
729 	/* Initialise video. */
730 	ret = uvcg_video_init(&uvc->video);
731 	if (ret < 0)
732 		goto error;
733 
734 	/* Register a V4L2 device. */
735 	ret = uvc_register_video(uvc);
736 	if (ret < 0) {
737 		printk(KERN_INFO "Unable to register video device\n");
738 		goto error;
739 	}
740 
741 	return 0;
742 
743 error:
744 	v4l2_device_unregister(&uvc->v4l2_dev);
745 
746 	if (uvc->control_req)
747 		usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
748 	kfree(uvc->control_buf);
749 
750 	usb_free_all_descriptors(f);
751 	return ret;
752 }
753 
754 /* --------------------------------------------------------------------------
755  * USB gadget function
756  */
757 
758 static void uvc_free_inst(struct usb_function_instance *f)
759 {
760 	struct f_uvc_opts *opts = fi_to_f_uvc_opts(f);
761 
762 	mutex_destroy(&opts->lock);
763 	kfree(opts);
764 }
765 
766 static struct usb_function_instance *uvc_alloc_inst(void)
767 {
768 	struct f_uvc_opts *opts;
769 	struct uvc_camera_terminal_descriptor *cd;
770 	struct uvc_processing_unit_descriptor *pd;
771 	struct uvc_output_terminal_descriptor *od;
772 	struct uvc_color_matching_descriptor *md;
773 	struct uvc_descriptor_header **ctl_cls;
774 
775 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
776 	if (!opts)
777 		return ERR_PTR(-ENOMEM);
778 	opts->func_inst.free_func_inst = uvc_free_inst;
779 	mutex_init(&opts->lock);
780 
781 	cd = &opts->uvc_camera_terminal;
782 	cd->bLength			= UVC_DT_CAMERA_TERMINAL_SIZE(3);
783 	cd->bDescriptorType		= USB_DT_CS_INTERFACE;
784 	cd->bDescriptorSubType		= UVC_VC_INPUT_TERMINAL;
785 	cd->bTerminalID			= 1;
786 	cd->wTerminalType		= cpu_to_le16(0x0201);
787 	cd->bAssocTerminal		= 0;
788 	cd->iTerminal			= 0;
789 	cd->wObjectiveFocalLengthMin	= cpu_to_le16(0);
790 	cd->wObjectiveFocalLengthMax	= cpu_to_le16(0);
791 	cd->wOcularFocalLength		= cpu_to_le16(0);
792 	cd->bControlSize		= 3;
793 	cd->bmControls[0]		= 2;
794 	cd->bmControls[1]		= 0;
795 	cd->bmControls[2]		= 0;
796 
797 	pd = &opts->uvc_processing;
798 	pd->bLength			= UVC_DT_PROCESSING_UNIT_SIZE(2);
799 	pd->bDescriptorType		= USB_DT_CS_INTERFACE;
800 	pd->bDescriptorSubType		= UVC_VC_PROCESSING_UNIT;
801 	pd->bUnitID			= 2;
802 	pd->bSourceID			= 1;
803 	pd->wMaxMultiplier		= cpu_to_le16(16*1024);
804 	pd->bControlSize		= 2;
805 	pd->bmControls[0]		= 1;
806 	pd->bmControls[1]		= 0;
807 	pd->iProcessing			= 0;
808 
809 	od = &opts->uvc_output_terminal;
810 	od->bLength			= UVC_DT_OUTPUT_TERMINAL_SIZE;
811 	od->bDescriptorType		= USB_DT_CS_INTERFACE;
812 	od->bDescriptorSubType		= UVC_VC_OUTPUT_TERMINAL;
813 	od->bTerminalID			= 3;
814 	od->wTerminalType		= cpu_to_le16(0x0101);
815 	od->bAssocTerminal		= 0;
816 	od->bSourceID			= 2;
817 	od->iTerminal			= 0;
818 
819 	md = &opts->uvc_color_matching;
820 	md->bLength			= UVC_DT_COLOR_MATCHING_SIZE;
821 	md->bDescriptorType		= USB_DT_CS_INTERFACE;
822 	md->bDescriptorSubType		= UVC_VS_COLORFORMAT;
823 	md->bColorPrimaries		= 1;
824 	md->bTransferCharacteristics	= 1;
825 	md->bMatrixCoefficients		= 4;
826 
827 	/* Prepare fs control class descriptors for configfs-based gadgets */
828 	ctl_cls = opts->uvc_fs_control_cls;
829 	ctl_cls[0] = NULL;	/* assigned elsewhere by configfs */
830 	ctl_cls[1] = (struct uvc_descriptor_header *)cd;
831 	ctl_cls[2] = (struct uvc_descriptor_header *)pd;
832 	ctl_cls[3] = (struct uvc_descriptor_header *)od;
833 	ctl_cls[4] = NULL;	/* NULL-terminate */
834 	opts->fs_control =
835 		(const struct uvc_descriptor_header * const *)ctl_cls;
836 
837 	/* Prepare hs control class descriptors for configfs-based gadgets */
838 	ctl_cls = opts->uvc_ss_control_cls;
839 	ctl_cls[0] = NULL;	/* assigned elsewhere by configfs */
840 	ctl_cls[1] = (struct uvc_descriptor_header *)cd;
841 	ctl_cls[2] = (struct uvc_descriptor_header *)pd;
842 	ctl_cls[3] = (struct uvc_descriptor_header *)od;
843 	ctl_cls[4] = NULL;	/* NULL-terminate */
844 	opts->ss_control =
845 		(const struct uvc_descriptor_header * const *)ctl_cls;
846 
847 	opts->streaming_interval = 1;
848 	opts->streaming_maxpacket = 1024;
849 
850 	uvcg_attach_configfs(opts);
851 	return &opts->func_inst;
852 }
853 
854 static void uvc_free(struct usb_function *f)
855 {
856 	struct uvc_device *uvc = to_uvc(f);
857 	struct f_uvc_opts *opts = container_of(f->fi, struct f_uvc_opts,
858 					       func_inst);
859 	--opts->refcnt;
860 	kfree(uvc);
861 }
862 
863 static void uvc_unbind(struct usb_configuration *c, struct usb_function *f)
864 {
865 	struct usb_composite_dev *cdev = c->cdev;
866 	struct uvc_device *uvc = to_uvc(f);
867 
868 	INFO(cdev, "%s\n", __func__);
869 
870 	video_unregister_device(&uvc->vdev);
871 	v4l2_device_unregister(&uvc->v4l2_dev);
872 
873 	usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
874 	kfree(uvc->control_buf);
875 
876 	usb_free_all_descriptors(f);
877 }
878 
879 static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
880 {
881 	struct uvc_device *uvc;
882 	struct f_uvc_opts *opts;
883 	struct uvc_descriptor_header **strm_cls;
884 
885 	uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
886 	if (uvc == NULL)
887 		return ERR_PTR(-ENOMEM);
888 
889 	mutex_init(&uvc->video.mutex);
890 	uvc->state = UVC_STATE_DISCONNECTED;
891 	opts = fi_to_f_uvc_opts(fi);
892 
893 	mutex_lock(&opts->lock);
894 	if (opts->uvc_fs_streaming_cls) {
895 		strm_cls = opts->uvc_fs_streaming_cls;
896 		opts->fs_streaming =
897 			(const struct uvc_descriptor_header * const *)strm_cls;
898 	}
899 	if (opts->uvc_hs_streaming_cls) {
900 		strm_cls = opts->uvc_hs_streaming_cls;
901 		opts->hs_streaming =
902 			(const struct uvc_descriptor_header * const *)strm_cls;
903 	}
904 	if (opts->uvc_ss_streaming_cls) {
905 		strm_cls = opts->uvc_ss_streaming_cls;
906 		opts->ss_streaming =
907 			(const struct uvc_descriptor_header * const *)strm_cls;
908 	}
909 
910 	uvc->desc.fs_control = opts->fs_control;
911 	uvc->desc.ss_control = opts->ss_control;
912 	uvc->desc.fs_streaming = opts->fs_streaming;
913 	uvc->desc.hs_streaming = opts->hs_streaming;
914 	uvc->desc.ss_streaming = opts->ss_streaming;
915 	++opts->refcnt;
916 	mutex_unlock(&opts->lock);
917 
918 	/* Register the function. */
919 	uvc->func.name = "uvc";
920 	uvc->func.bind = uvc_function_bind;
921 	uvc->func.unbind = uvc_unbind;
922 	uvc->func.get_alt = uvc_function_get_alt;
923 	uvc->func.set_alt = uvc_function_set_alt;
924 	uvc->func.disable = uvc_function_disable;
925 	uvc->func.setup = uvc_function_setup;
926 	uvc->func.free_func = uvc_free;
927 	uvc->func.bind_deactivated = true;
928 
929 	return &uvc->func;
930 }
931 
932 DECLARE_USB_FUNCTION_INIT(uvc, uvc_alloc_inst, uvc_alloc);
933 MODULE_LICENSE("GPL");
934 MODULE_AUTHOR("Laurent Pinchart");
935