1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 *	uvc_gadget.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/fs.h>
  12#include <linux/kernel.h>
  13#include <linux/list.h>
  14#include <linux/module.h>
  15#include <linux/mutex.h>
  16#include <linux/string.h>
  17#include <linux/usb/ch9.h>
  18#include <linux/usb/gadget.h>
  19#include <linux/usb/g_uvc.h>
  20#include <linux/usb/video.h>
  21#include <linux/vmalloc.h>
  22#include <linux/wait.h>
  23
  24#include <media/v4l2-dev.h>
  25#include <media/v4l2-event.h>
  26
 
  27#include "uvc.h"
  28#include "uvc_configfs.h"
  29#include "uvc_v4l2.h"
  30#include "uvc_video.h"
  31
  32unsigned int uvc_gadget_trace_param;
  33module_param_named(trace, uvc_gadget_trace_param, uint, 0644);
  34MODULE_PARM_DESC(trace, "Trace level bitmask");
  35
  36/* --------------------------------------------------------------------------
  37 * Function descriptors
  38 */
  39
  40/* string IDs are assigned dynamically */
  41
 
 
 
  42static struct usb_string uvc_en_us_strings[] = {
  43	/* [UVC_STRING_CONTROL_IDX].s = DYNAMIC, */
  44	[UVC_STRING_STREAMING_IDX].s = "Video Streaming",
  45	{  }
  46};
  47
  48static struct usb_gadget_strings uvc_stringtab = {
  49	.language = 0x0409,	/* en-us */
  50	.strings = uvc_en_us_strings,
  51};
  52
  53static struct usb_gadget_strings *uvc_function_strings[] = {
  54	&uvc_stringtab,
  55	NULL,
  56};
  57
  58#define UVC_INTF_VIDEO_CONTROL			0
  59#define UVC_INTF_VIDEO_STREAMING		1
  60
  61#define UVC_STATUS_MAX_PACKET_SIZE		16	/* 16 bytes status */
  62
  63static struct usb_interface_assoc_descriptor uvc_iad = {
  64	.bLength		= sizeof(uvc_iad),
  65	.bDescriptorType	= USB_DT_INTERFACE_ASSOCIATION,
  66	.bFirstInterface	= 0,
  67	.bInterfaceCount	= 2,
  68	.bFunctionClass		= USB_CLASS_VIDEO,
  69	.bFunctionSubClass	= UVC_SC_VIDEO_INTERFACE_COLLECTION,
  70	.bFunctionProtocol	= 0x00,
  71	.iFunction		= 0,
  72};
  73
  74static struct usb_interface_descriptor uvc_control_intf = {
  75	.bLength		= USB_DT_INTERFACE_SIZE,
  76	.bDescriptorType	= USB_DT_INTERFACE,
  77	.bInterfaceNumber	= UVC_INTF_VIDEO_CONTROL,
  78	.bAlternateSetting	= 0,
  79	.bNumEndpoints		= 0,
  80	.bInterfaceClass	= USB_CLASS_VIDEO,
  81	.bInterfaceSubClass	= UVC_SC_VIDEOCONTROL,
  82	.bInterfaceProtocol	= 0x00,
  83	.iInterface		= 0,
  84};
  85
  86static struct usb_endpoint_descriptor uvc_interrupt_ep = {
  87	.bLength		= USB_DT_ENDPOINT_SIZE,
  88	.bDescriptorType	= USB_DT_ENDPOINT,
  89	.bEndpointAddress	= USB_DIR_IN,
  90	.bmAttributes		= USB_ENDPOINT_XFER_INT,
  91	.wMaxPacketSize		= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
  92	.bInterval		= 8,
  93};
  94
  95static struct usb_ss_ep_comp_descriptor uvc_ss_interrupt_comp = {
  96	.bLength		= sizeof(uvc_ss_interrupt_comp),
  97	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
  98	/* The following 3 values can be tweaked if necessary. */
  99	.bMaxBurst		= 0,
 100	.bmAttributes		= 0,
 101	.wBytesPerInterval	= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 102};
 103
 104static struct uvc_control_endpoint_descriptor uvc_interrupt_cs_ep = {
 105	.bLength		= UVC_DT_CONTROL_ENDPOINT_SIZE,
 106	.bDescriptorType	= USB_DT_CS_ENDPOINT,
 107	.bDescriptorSubType	= UVC_EP_INTERRUPT,
 108	.wMaxTransferSize	= cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
 109};
 110
 111static struct usb_interface_descriptor uvc_streaming_intf_alt0 = {
 112	.bLength		= USB_DT_INTERFACE_SIZE,
 113	.bDescriptorType	= USB_DT_INTERFACE,
 114	.bInterfaceNumber	= UVC_INTF_VIDEO_STREAMING,
 115	.bAlternateSetting	= 0,
 116	.bNumEndpoints		= 0,
 117	.bInterfaceClass	= USB_CLASS_VIDEO,
 118	.bInterfaceSubClass	= UVC_SC_VIDEOSTREAMING,
 119	.bInterfaceProtocol	= 0x00,
 120	.iInterface		= 0,
 121};
 122
 123static struct usb_interface_descriptor uvc_streaming_intf_alt1 = {
 124	.bLength		= USB_DT_INTERFACE_SIZE,
 125	.bDescriptorType	= USB_DT_INTERFACE,
 126	.bInterfaceNumber	= UVC_INTF_VIDEO_STREAMING,
 127	.bAlternateSetting	= 1,
 128	.bNumEndpoints		= 1,
 129	.bInterfaceClass	= USB_CLASS_VIDEO,
 130	.bInterfaceSubClass	= UVC_SC_VIDEOSTREAMING,
 131	.bInterfaceProtocol	= 0x00,
 132	.iInterface		= 0,
 133};
 134
 135static struct usb_endpoint_descriptor uvc_fs_streaming_ep = {
 136	.bLength		= USB_DT_ENDPOINT_SIZE,
 137	.bDescriptorType	= USB_DT_ENDPOINT,
 138	.bEndpointAddress	= USB_DIR_IN,
 139	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
 140				| USB_ENDPOINT_XFER_ISOC,
 141	/*
 142	 * The wMaxPacketSize and bInterval values will be initialized from
 143	 * module parameters.
 144	 */
 145};
 146
 147static struct usb_endpoint_descriptor uvc_hs_streaming_ep = {
 148	.bLength		= USB_DT_ENDPOINT_SIZE,
 149	.bDescriptorType	= USB_DT_ENDPOINT,
 150	.bEndpointAddress	= USB_DIR_IN,
 151	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
 152				| USB_ENDPOINT_XFER_ISOC,
 153	/*
 154	 * The wMaxPacketSize and bInterval values will be initialized from
 155	 * module parameters.
 156	 */
 157};
 158
 159static struct usb_endpoint_descriptor uvc_ss_streaming_ep = {
 160	.bLength		= USB_DT_ENDPOINT_SIZE,
 161	.bDescriptorType	= USB_DT_ENDPOINT,
 162
 163	.bEndpointAddress	= USB_DIR_IN,
 164	.bmAttributes		= USB_ENDPOINT_SYNC_ASYNC
 165				| USB_ENDPOINT_XFER_ISOC,
 166	/*
 167	 * The wMaxPacketSize and bInterval values will be initialized from
 168	 * module parameters.
 169	 */
 170};
 171
 172static struct usb_ss_ep_comp_descriptor uvc_ss_streaming_comp = {
 173	.bLength		= sizeof(uvc_ss_streaming_comp),
 174	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
 175	/*
 176	 * The bMaxBurst, bmAttributes and wBytesPerInterval values will be
 177	 * initialized from module parameters.
 178	 */
 179};
 180
 181static 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
 187static 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
 193static 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/* --------------------------------------------------------------------------
 201 * Control requests
 202 */
 203
 204static void
 205uvc_function_ep0_complete(struct usb_ep *ep, struct usb_request *req)
 206{
 207	struct uvc_device *uvc = req->context;
 208	struct v4l2_event v4l2_event;
 209	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 210
 211	if (uvc->event_setup_out) {
 212		uvc->event_setup_out = 0;
 213
 214		memset(&v4l2_event, 0, sizeof(v4l2_event));
 215		v4l2_event.type = UVC_EVENT_DATA;
 216		uvc_event->data.length = min_t(unsigned int, req->actual,
 217			sizeof(uvc_event->data.data));
 218		memcpy(&uvc_event->data.data, req->buf, uvc_event->data.length);
 219		v4l2_event_queue(&uvc->vdev, &v4l2_event);
 220	}
 221}
 222
 223static int
 224uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 225{
 226	struct uvc_device *uvc = to_uvc(f);
 227	struct v4l2_event v4l2_event;
 228	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 229	unsigned int interface = le16_to_cpu(ctrl->wIndex) & 0xff;
 230	struct usb_ctrlrequest *mctrl;
 231
 232	if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) {
 233		uvcg_info(f, "invalid request type\n");
 234		return -EINVAL;
 235	}
 236
 237	/* Stall too big requests. */
 238	if (le16_to_cpu(ctrl->wLength) > UVC_MAX_REQUEST_SIZE)
 239		return -EINVAL;
 240
 241	/*
 242	 * Tell the complete callback to generate an event for the next request
 243	 * that will be enqueued by UVCIOC_SEND_RESPONSE.
 244	 */
 245	uvc->event_setup_out = !(ctrl->bRequestType & USB_DIR_IN);
 246	uvc->event_length = le16_to_cpu(ctrl->wLength);
 247
 248	memset(&v4l2_event, 0, sizeof(v4l2_event));
 249	v4l2_event.type = UVC_EVENT_SETUP;
 250	memcpy(&uvc_event->req, ctrl, sizeof(uvc_event->req));
 251
 252	/* check for the interface number, fixup the interface number in
 253	 * the ctrl request so the userspace doesn't have to bother with
 254	 * offset and configfs parsing
 255	 */
 256	mctrl = &uvc_event->req;
 257	mctrl->wIndex &= ~cpu_to_le16(0xff);
 258	if (interface == uvc->streaming_intf)
 259		mctrl->wIndex = cpu_to_le16(UVC_STRING_STREAMING_IDX);
 260
 261	v4l2_event_queue(&uvc->vdev, &v4l2_event);
 262
 263	return 0;
 264}
 265
 266void uvc_function_setup_continue(struct uvc_device *uvc, int disable_ep)
 267{
 268	struct usb_composite_dev *cdev = uvc->func.config->cdev;
 269
 270	if (disable_ep && uvc->video.ep)
 271		usb_ep_disable(uvc->video.ep);
 272
 273	usb_composite_setup_continue(cdev);
 274}
 275
 276static int
 277uvc_function_get_alt(struct usb_function *f, unsigned interface)
 278{
 279	struct uvc_device *uvc = to_uvc(f);
 280
 281	uvcg_info(f, "%s(%u)\n", __func__, interface);
 282
 283	if (interface == uvc->control_intf)
 284		return 0;
 285	else if (interface != uvc->streaming_intf)
 286		return -EINVAL;
 287	else
 288		return uvc->video.ep->enabled ? 1 : 0;
 289}
 290
 291static int
 292uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
 293{
 294	struct uvc_device *uvc = to_uvc(f);
 295	struct usb_composite_dev *cdev = f->config->cdev;
 296	struct v4l2_event v4l2_event;
 297	struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
 298	int ret;
 299
 300	uvcg_info(f, "%s(%u, %u)\n", __func__, interface, alt);
 301
 302	if (interface == uvc->control_intf) {
 303		if (alt)
 304			return -EINVAL;
 305
 306		if (uvc->enable_interrupt_ep) {
 307			uvcg_info(f, "reset UVC interrupt endpoint\n");
 308			usb_ep_disable(uvc->interrupt_ep);
 309
 310			if (!uvc->interrupt_ep->desc)
 311				if (config_ep_by_speed(cdev->gadget, f,
 312						       uvc->interrupt_ep))
 313					return -EINVAL;
 314
 315			usb_ep_enable(uvc->interrupt_ep);
 316		}
 
 
 
 317
 318		if (uvc->state == UVC_STATE_DISCONNECTED) {
 319			memset(&v4l2_event, 0, sizeof(v4l2_event));
 320			v4l2_event.type = UVC_EVENT_CONNECT;
 321			uvc_event->speed = cdev->gadget->speed;
 322			v4l2_event_queue(&uvc->vdev, &v4l2_event);
 323
 324			uvc->state = UVC_STATE_CONNECTED;
 325		}
 326
 327		return 0;
 328	}
 329
 330	if (interface != uvc->streaming_intf)
 331		return -EINVAL;
 332
 333	/* TODO
 334	if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
 335		return alt ? -EINVAL : 0;
 336	*/
 337
 338	switch (alt) {
 339	case 0:
 340		if (uvc->state != UVC_STATE_STREAMING)
 341			return 0;
 342
 
 
 
 343		memset(&v4l2_event, 0, sizeof(v4l2_event));
 344		v4l2_event.type = UVC_EVENT_STREAMOFF;
 345		v4l2_event_queue(&uvc->vdev, &v4l2_event);
 346
 347		return USB_GADGET_DELAYED_STATUS;
 
 348
 349	case 1:
 350		if (uvc->state != UVC_STATE_CONNECTED)
 351			return 0;
 352
 353		if (!uvc->video.ep)
 354			return -EINVAL;
 355
 356		uvcg_info(f, "reset UVC\n");
 357		usb_ep_disable(uvc->video.ep);
 358
 359		ret = config_ep_by_speed(f->config->cdev->gadget,
 360				&(uvc->func), uvc->video.ep);
 361		if (ret)
 362			return ret;
 363		usb_ep_enable(uvc->video.ep);
 364
 365		memset(&v4l2_event, 0, sizeof(v4l2_event));
 366		v4l2_event.type = UVC_EVENT_STREAMON;
 367		v4l2_event_queue(&uvc->vdev, &v4l2_event);
 368		return USB_GADGET_DELAYED_STATUS;
 369
 370	default:
 371		return -EINVAL;
 372	}
 373}
 374
 375static void
 376uvc_function_disable(struct usb_function *f)
 377{
 378	struct uvc_device *uvc = to_uvc(f);
 379	struct v4l2_event v4l2_event;
 380
 381	uvcg_info(f, "%s()\n", __func__);
 382
 383	memset(&v4l2_event, 0, sizeof(v4l2_event));
 384	v4l2_event.type = UVC_EVENT_DISCONNECT;
 385	v4l2_event_queue(&uvc->vdev, &v4l2_event);
 386
 387	uvc->state = UVC_STATE_DISCONNECTED;
 388
 389	usb_ep_disable(uvc->video.ep);
 390	if (uvc->enable_interrupt_ep)
 391		usb_ep_disable(uvc->interrupt_ep);
 392}
 393
 394/* --------------------------------------------------------------------------
 395 * Connection / disconnection
 396 */
 397
 398void
 399uvc_function_connect(struct uvc_device *uvc)
 400{
 401	int ret;
 402
 403	if ((ret = usb_function_activate(&uvc->func)) < 0)
 404		uvcg_info(&uvc->func, "UVC connect failed with %d\n", ret);
 405}
 406
 407void
 408uvc_function_disconnect(struct uvc_device *uvc)
 409{
 410	int ret;
 411
 412	if ((ret = usb_function_deactivate(&uvc->func)) < 0)
 413		uvcg_info(&uvc->func, "UVC disconnect failed with %d\n", ret);
 414}
 415
 416/* --------------------------------------------------------------------------
 417 * USB probe and disconnect
 418 */
 419
 420static ssize_t function_name_show(struct device *dev,
 421				  struct device_attribute *attr, char *buf)
 422{
 423	struct uvc_device *uvc = dev_get_drvdata(dev);
 424
 425	return sprintf(buf, "%s\n", uvc->func.fi->group.cg_item.ci_name);
 426}
 427
 428static DEVICE_ATTR_RO(function_name);
 429
 430static int
 431uvc_register_video(struct uvc_device *uvc)
 432{
 433	struct usb_composite_dev *cdev = uvc->func.config->cdev;
 434	int ret;
 435
 436	/* TODO reference counting. */
 437	memset(&uvc->vdev, 0, sizeof(uvc->vdev));
 438	uvc->vdev.v4l2_dev = &uvc->v4l2_dev;
 439	uvc->vdev.v4l2_dev->dev = &cdev->gadget->dev;
 440	uvc->vdev.fops = &uvc_v4l2_fops;
 441	uvc->vdev.ioctl_ops = &uvc_v4l2_ioctl_ops;
 442	uvc->vdev.release = video_device_release_empty;
 443	uvc->vdev.vfl_dir = VFL_DIR_TX;
 444	uvc->vdev.lock = &uvc->video.mutex;
 445	uvc->vdev.device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 446	strscpy(uvc->vdev.name, cdev->gadget->name, sizeof(uvc->vdev.name));
 447
 448	video_set_drvdata(&uvc->vdev, uvc);
 449
 450	ret = video_register_device(&uvc->vdev, VFL_TYPE_VIDEO, -1);
 451	if (ret < 0)
 452		return ret;
 453
 454	ret = device_create_file(&uvc->vdev.dev, &dev_attr_function_name);
 455	if (ret < 0) {
 456		video_unregister_device(&uvc->vdev);
 457		return ret;
 458	}
 459
 460	return 0;
 461}
 462
 463#define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
 464	do { \
 465		memcpy(mem, desc, (desc)->bLength); \
 466		*(dst)++ = mem; \
 467		mem += (desc)->bLength; \
 468	} while (0);
 469
 470#define UVC_COPY_DESCRIPTORS(mem, dst, src) \
 471	do { \
 472		const struct usb_descriptor_header * const *__src; \
 473		for (__src = src; *__src; ++__src) { \
 474			memcpy(mem, *__src, (*__src)->bLength); \
 475			*dst++ = mem; \
 476			mem += (*__src)->bLength; \
 477		} \
 478	} while (0)
 479
 480#define UVC_COPY_XU_DESCRIPTOR(mem, dst, desc)					\
 481	do {									\
 482		*(dst)++ = mem;							\
 483		memcpy(mem, desc, 22); /* bLength to bNrInPins */		\
 484		mem += 22;							\
 485										\
 486		memcpy(mem, (desc)->baSourceID, (desc)->bNrInPins);		\
 487		mem += (desc)->bNrInPins;					\
 488										\
 489		memcpy(mem, &(desc)->bControlSize, 1);				\
 490		mem++;								\
 491										\
 492		memcpy(mem, (desc)->bmControls, (desc)->bControlSize);		\
 493		mem += (desc)->bControlSize;					\
 494										\
 495		memcpy(mem, &(desc)->iExtension, 1);				\
 496		mem++;								\
 497	} while (0)
 498
 499static struct usb_descriptor_header **
 500uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 501{
 502	struct uvc_input_header_descriptor *uvc_streaming_header;
 503	struct uvc_header_descriptor *uvc_control_header;
 504	const struct uvc_descriptor_header * const *uvc_control_desc;
 505	const struct uvc_descriptor_header * const *uvc_streaming_cls;
 506	const struct usb_descriptor_header * const *uvc_streaming_std;
 507	const struct usb_descriptor_header * const *src;
 508	struct usb_descriptor_header **dst;
 509	struct usb_descriptor_header **hdr;
 510	struct uvcg_extension *xu;
 511	unsigned int control_size;
 512	unsigned int streaming_size;
 513	unsigned int n_desc;
 514	unsigned int bytes;
 515	void *mem;
 516
 517	switch (speed) {
 518	case USB_SPEED_SUPER_PLUS:
 519	case USB_SPEED_SUPER:
 520		uvc_control_desc = uvc->desc.ss_control;
 521		uvc_streaming_cls = uvc->desc.ss_streaming;
 522		uvc_streaming_std = uvc_ss_streaming;
 523		break;
 524
 525	case USB_SPEED_HIGH:
 526		uvc_control_desc = uvc->desc.fs_control;
 527		uvc_streaming_cls = uvc->desc.hs_streaming;
 528		uvc_streaming_std = uvc_hs_streaming;
 529		break;
 530
 531	case USB_SPEED_FULL:
 532	default:
 533		uvc_control_desc = uvc->desc.fs_control;
 534		uvc_streaming_cls = uvc->desc.fs_streaming;
 535		uvc_streaming_std = uvc_fs_streaming;
 536		break;
 537	}
 538
 539	if (!uvc_control_desc || !uvc_streaming_cls)
 540		return ERR_PTR(-ENODEV);
 541
 542	/*
 543	 * Descriptors layout
 544	 *
 545	 * uvc_iad
 546	 * uvc_control_intf
 547	 * Class-specific UVC control descriptors
 548	 * uvc_interrupt_ep
 549	 * uvc_interrupt_cs_ep
 550	 * uvc_ss_interrupt_comp (for SS only)
 551	 * uvc_streaming_intf_alt0
 552	 * Class-specific UVC streaming descriptors
 553	 * uvc_{fs|hs}_streaming
 554	 */
 555
 556	/* Count descriptors and compute their size. */
 557	control_size = 0;
 558	streaming_size = 0;
 559	bytes = uvc_iad.bLength + uvc_control_intf.bLength
 
 560	      + uvc_streaming_intf_alt0.bLength;
 561
 562	n_desc = 3;
 563	if (uvc->enable_interrupt_ep) {
 564		bytes += uvc_interrupt_ep.bLength + uvc_interrupt_cs_ep.bLength;
 565		n_desc += 2;
 566
 567		if (speed == USB_SPEED_SUPER ||
 568		    speed == USB_SPEED_SUPER_PLUS) {
 569			bytes += uvc_ss_interrupt_comp.bLength;
 570			n_desc += 1;
 571		}
 572	}
 573
 574	for (src = (const struct usb_descriptor_header **)uvc_control_desc;
 575	     *src; ++src) {
 576		control_size += (*src)->bLength;
 577		bytes += (*src)->bLength;
 578		n_desc++;
 579	}
 580
 581	list_for_each_entry(xu, uvc->desc.extension_units, list) {
 582		control_size += xu->desc.bLength;
 583		bytes += xu->desc.bLength;
 584		n_desc++;
 585	}
 586
 587	for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
 588	     *src; ++src) {
 589		streaming_size += (*src)->bLength;
 590		bytes += (*src)->bLength;
 591		n_desc++;
 592	}
 593	for (src = uvc_streaming_std; *src; ++src) {
 594		bytes += (*src)->bLength;
 595		n_desc++;
 596	}
 597
 598	mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
 599	if (mem == NULL)
 600		return NULL;
 601
 602	hdr = mem;
 603	dst = mem;
 604	mem += (n_desc + 1) * sizeof(*src);
 605
 606	/* Copy the descriptors. */
 607	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
 608	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
 609
 610	uvc_control_header = mem;
 611	UVC_COPY_DESCRIPTORS(mem, dst,
 612		(const struct usb_descriptor_header **)uvc_control_desc);
 613
 614	list_for_each_entry(xu, uvc->desc.extension_units, list)
 615		UVC_COPY_XU_DESCRIPTOR(mem, dst, &xu->desc);
 616
 617	uvc_control_header->wTotalLength = cpu_to_le16(control_size);
 618	uvc_control_header->bInCollection = 1;
 619	uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 620
 621	if (uvc->enable_interrupt_ep) {
 622		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_ep);
 623		if (speed == USB_SPEED_SUPER ||
 624		    speed == USB_SPEED_SUPER_PLUS)
 625			UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_interrupt_comp);
 626
 627		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_cs_ep);
 628	}
 629
 
 630	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
 631
 632	uvc_streaming_header = mem;
 633	UVC_COPY_DESCRIPTORS(mem, dst,
 634		(const struct usb_descriptor_header**)uvc_streaming_cls);
 635	uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
 636	uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
 637
 638	UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
 639
 640	*dst = NULL;
 641	return hdr;
 642}
 643
 644static int
 645uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 646{
 647	struct usb_composite_dev *cdev = c->cdev;
 648	struct uvc_device *uvc = to_uvc(f);
 649	struct uvcg_extension *xu;
 650	struct usb_string *us;
 651	unsigned int max_packet_mult;
 652	unsigned int max_packet_size;
 653	struct usb_ep *ep;
 654	struct f_uvc_opts *opts;
 655	int ret = -EINVAL;
 656
 657	uvcg_info(f, "%s()\n", __func__);
 658
 659	opts = fi_to_f_uvc_opts(f->fi);
 660	/* Sanity check the streaming endpoint module parameters. */
 
 661	opts->streaming_interval = clamp(opts->streaming_interval, 1U, 16U);
 662	opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U);
 663	opts->streaming_maxburst = min(opts->streaming_maxburst, 15U);
 664
 665	/* For SS, wMaxPacketSize has to be 1024 if bMaxBurst is not 0 */
 666	if (opts->streaming_maxburst &&
 667	    (opts->streaming_maxpacket % 1024) != 0) {
 668		opts->streaming_maxpacket = roundup(opts->streaming_maxpacket, 1024);
 669		uvcg_info(f, "overriding streaming_maxpacket to %d\n",
 670			  opts->streaming_maxpacket);
 671	}
 672
 673	/*
 674	 * Fill in the FS/HS/SS Video Streaming specific descriptors from the
 675	 * module parameters.
 676	 *
 677	 * NOTE: We assume that the user knows what they are doing and won't
 678	 * give parameters that their UDC doesn't support.
 679	 */
 680	if (opts->streaming_maxpacket <= 1024) {
 681		max_packet_mult = 1;
 682		max_packet_size = opts->streaming_maxpacket;
 683	} else if (opts->streaming_maxpacket <= 2048) {
 684		max_packet_mult = 2;
 685		max_packet_size = opts->streaming_maxpacket / 2;
 686	} else {
 687		max_packet_mult = 3;
 688		max_packet_size = opts->streaming_maxpacket / 3;
 689	}
 690
 691	uvc_fs_streaming_ep.wMaxPacketSize =
 692		cpu_to_le16(min(opts->streaming_maxpacket, 1023U));
 693	uvc_fs_streaming_ep.bInterval = opts->streaming_interval;
 694
 695	uvc_hs_streaming_ep.wMaxPacketSize =
 696		cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));
 697
 698	/* A high-bandwidth endpoint must specify a bInterval value of 1 */
 699	if (max_packet_mult > 1)
 700		uvc_hs_streaming_ep.bInterval = 1;
 701	else
 702		uvc_hs_streaming_ep.bInterval = opts->streaming_interval;
 703
 704	uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);
 705	uvc_ss_streaming_ep.bInterval = opts->streaming_interval;
 706	uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
 707	uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
 708	uvc_ss_streaming_comp.wBytesPerInterval =
 709		cpu_to_le16(max_packet_size * max_packet_mult *
 710			    (opts->streaming_maxburst + 1));
 711
 712	/* Allocate endpoints. */
 713	if (opts->enable_interrupt_ep) {
 714		ep = usb_ep_autoconfig(cdev->gadget, &uvc_interrupt_ep);
 715		if (!ep) {
 716			uvcg_info(f, "Unable to allocate interrupt EP\n");
 717			goto error;
 718		}
 719		uvc->interrupt_ep = ep;
 720		uvc_control_intf.bNumEndpoints = 1;
 721	}
 722	uvc->enable_interrupt_ep = opts->enable_interrupt_ep;
 723
 724	/*
 725	 * gadget_is_{super|dual}speed() API check UDC controller capitblity. It should pass down
 726	 * highest speed endpoint descriptor to UDC controller. So UDC controller driver can reserve
 727	 * enough resource at check_config(), especially mult and maxburst. So UDC driver (such as
 728	 * cdns3) can know need at least (mult + 1) * (maxburst + 1) * wMaxPacketSize internal
 729	 * memory for this uvc functions. This is the only straightforward method to resolve the UDC
 730	 * resource allocation issue in the current gadget framework.
 731	 */
 732	if (gadget_is_superspeed(c->cdev->gadget))
 733		ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
 734					  &uvc_ss_streaming_comp);
 735	else if (gadget_is_dualspeed(cdev->gadget))
 736		ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
 737	else
 738		ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
 739
 740	if (!ep) {
 741		uvcg_info(f, "Unable to allocate streaming EP\n");
 742		goto error;
 743	}
 744	uvc->video.ep = ep;
 745
 746	uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 747	uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 748	uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
 749
 750	/*
 751	 * XUs can have an arbitrary string descriptor describing them. If they
 752	 * have one pick up the ID.
 753	 */
 754	list_for_each_entry(xu, &opts->extension_units, list)
 755		if (xu->string_descriptor_index)
 756			xu->desc.iExtension = cdev->usb_strings[xu->string_descriptor_index].id;
 757
 758	/*
 759	 * We attach the hard-coded defaults incase the user does not provide
 760	 * any more appropriate strings through configfs.
 761	 */
 762	uvc_en_us_strings[UVC_STRING_CONTROL_IDX].s = opts->function_name;
 763	us = usb_gstrings_attach(cdev, uvc_function_strings,
 764				 ARRAY_SIZE(uvc_en_us_strings));
 765	if (IS_ERR(us)) {
 766		ret = PTR_ERR(us);
 767		goto error;
 768	}
 769
 770	uvc_iad.iFunction = opts->iad_index ? cdev->usb_strings[opts->iad_index].id :
 771			    us[UVC_STRING_CONTROL_IDX].id;
 772	uvc_streaming_intf_alt0.iInterface = opts->vs0_index ?
 773					     cdev->usb_strings[opts->vs0_index].id :
 774					     us[UVC_STRING_STREAMING_IDX].id;
 775	uvc_streaming_intf_alt1.iInterface = opts->vs1_index ?
 776					     cdev->usb_strings[opts->vs1_index].id :
 777					     us[UVC_STRING_STREAMING_IDX].id;
 778
 779	/* Allocate interface IDs. */
 780	if ((ret = usb_interface_id(c, f)) < 0)
 781		goto error;
 782	uvc_iad.bFirstInterface = ret;
 783	uvc_control_intf.bInterfaceNumber = ret;
 784	uvc->control_intf = ret;
 785	opts->control_interface = ret;
 786
 787	if ((ret = usb_interface_id(c, f)) < 0)
 788		goto error;
 789	uvc_streaming_intf_alt0.bInterfaceNumber = ret;
 790	uvc_streaming_intf_alt1.bInterfaceNumber = ret;
 791	uvc->streaming_intf = ret;
 792	opts->streaming_interface = ret;
 793
 794	/* Copy descriptors */
 795	f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
 796	if (IS_ERR(f->fs_descriptors)) {
 797		ret = PTR_ERR(f->fs_descriptors);
 798		f->fs_descriptors = NULL;
 799		goto error;
 800	}
 801
 802	f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
 803	if (IS_ERR(f->hs_descriptors)) {
 804		ret = PTR_ERR(f->hs_descriptors);
 805		f->hs_descriptors = NULL;
 806		goto error;
 807	}
 808
 809	f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
 810	if (IS_ERR(f->ss_descriptors)) {
 811		ret = PTR_ERR(f->ss_descriptors);
 812		f->ss_descriptors = NULL;
 813		goto error;
 814	}
 815
 816	f->ssp_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER_PLUS);
 817	if (IS_ERR(f->ssp_descriptors)) {
 818		ret = PTR_ERR(f->ssp_descriptors);
 819		f->ssp_descriptors = NULL;
 820		goto error;
 
 821	}
 822
 823	/* Preallocate control endpoint request. */
 824	uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 825	uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
 826	if (uvc->control_req == NULL || uvc->control_buf == NULL) {
 827		ret = -ENOMEM;
 828		goto error;
 829	}
 830
 831	uvc->control_req->buf = uvc->control_buf;
 832	uvc->control_req->complete = uvc_function_ep0_complete;
 833	uvc->control_req->context = uvc;
 834
 835	if (v4l2_device_register(&cdev->gadget->dev, &uvc->v4l2_dev)) {
 836		uvcg_err(f, "failed to register V4L2 device\n");
 837		goto error;
 838	}
 839
 840	/* Initialise video. */
 841	ret = uvcg_video_init(&uvc->video, uvc);
 842	if (ret < 0)
 843		goto v4l2_error;
 844
 845	/* Register a V4L2 device. */
 846	ret = uvc_register_video(uvc);
 847	if (ret < 0) {
 848		uvcg_err(f, "failed to register video device\n");
 849		goto v4l2_error;
 850	}
 851
 852	return 0;
 853
 854v4l2_error:
 855	v4l2_device_unregister(&uvc->v4l2_dev);
 856error:
 
 
 857	if (uvc->control_req)
 858		usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
 859	kfree(uvc->control_buf);
 860
 861	usb_free_all_descriptors(f);
 862	return ret;
 863}
 864
 865/* --------------------------------------------------------------------------
 866 * USB gadget function
 867 */
 868
 869static void uvc_free_inst(struct usb_function_instance *f)
 870{
 871	struct f_uvc_opts *opts = fi_to_f_uvc_opts(f);
 872
 873	mutex_destroy(&opts->lock);
 874	kfree(opts);
 875}
 876
 877static struct usb_function_instance *uvc_alloc_inst(void)
 878{
 879	struct f_uvc_opts *opts;
 880	struct uvc_camera_terminal_descriptor *cd;
 881	struct uvc_processing_unit_descriptor *pd;
 882	struct uvc_output_terminal_descriptor *od;
 
 883	struct uvc_descriptor_header **ctl_cls;
 884	int ret;
 885
 886	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 887	if (!opts)
 888		return ERR_PTR(-ENOMEM);
 889	opts->func_inst.free_func_inst = uvc_free_inst;
 890	mutex_init(&opts->lock);
 891
 892	cd = &opts->uvc_camera_terminal;
 893	cd->bLength			= UVC_DT_CAMERA_TERMINAL_SIZE(3);
 894	cd->bDescriptorType		= USB_DT_CS_INTERFACE;
 895	cd->bDescriptorSubType		= UVC_VC_INPUT_TERMINAL;
 896	cd->bTerminalID			= 1;
 897	cd->wTerminalType		= cpu_to_le16(0x0201);
 898	cd->bAssocTerminal		= 0;
 899	cd->iTerminal			= 0;
 900	cd->wObjectiveFocalLengthMin	= cpu_to_le16(0);
 901	cd->wObjectiveFocalLengthMax	= cpu_to_le16(0);
 902	cd->wOcularFocalLength		= cpu_to_le16(0);
 903	cd->bControlSize		= 3;
 904	cd->bmControls[0]		= 2;
 905	cd->bmControls[1]		= 0;
 906	cd->bmControls[2]		= 0;
 907
 908	pd = &opts->uvc_processing;
 909	pd->bLength			= UVC_DT_PROCESSING_UNIT_SIZE(2);
 910	pd->bDescriptorType		= USB_DT_CS_INTERFACE;
 911	pd->bDescriptorSubType		= UVC_VC_PROCESSING_UNIT;
 912	pd->bUnitID			= 2;
 913	pd->bSourceID			= 1;
 914	pd->wMaxMultiplier		= cpu_to_le16(16*1024);
 915	pd->bControlSize		= 2;
 916	pd->bmControls[0]		= 1;
 917	pd->bmControls[1]		= 0;
 918	pd->iProcessing			= 0;
 919	pd->bmVideoStandards		= 0;
 920
 921	od = &opts->uvc_output_terminal;
 922	od->bLength			= UVC_DT_OUTPUT_TERMINAL_SIZE;
 923	od->bDescriptorType		= USB_DT_CS_INTERFACE;
 924	od->bDescriptorSubType		= UVC_VC_OUTPUT_TERMINAL;
 925	od->bTerminalID			= 3;
 926	od->wTerminalType		= cpu_to_le16(0x0101);
 927	od->bAssocTerminal		= 0;
 928	od->bSourceID			= 2;
 929	od->iTerminal			= 0;
 930
 931	/*
 932	 * With the ability to add XUs to the UVC function graph, we need to be
 933	 * able to allocate unique unit IDs to them. The IDs are 1-based, with
 934	 * the CT, PU and OT above consuming the first 3.
 935	 */
 936	opts->last_unit_id		= 3;
 
 937
 938	/* Prepare fs control class descriptors for configfs-based gadgets */
 939	ctl_cls = opts->uvc_fs_control_cls;
 940	ctl_cls[0] = NULL;	/* assigned elsewhere by configfs */
 941	ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 942	ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 943	ctl_cls[3] = (struct uvc_descriptor_header *)od;
 944	ctl_cls[4] = NULL;	/* NULL-terminate */
 945	opts->fs_control =
 946		(const struct uvc_descriptor_header * const *)ctl_cls;
 947
 948	/* Prepare hs control class descriptors for configfs-based gadgets */
 949	ctl_cls = opts->uvc_ss_control_cls;
 950	ctl_cls[0] = NULL;	/* assigned elsewhere by configfs */
 951	ctl_cls[1] = (struct uvc_descriptor_header *)cd;
 952	ctl_cls[2] = (struct uvc_descriptor_header *)pd;
 953	ctl_cls[3] = (struct uvc_descriptor_header *)od;
 954	ctl_cls[4] = NULL;	/* NULL-terminate */
 955	opts->ss_control =
 956		(const struct uvc_descriptor_header * const *)ctl_cls;
 957
 958	INIT_LIST_HEAD(&opts->extension_units);
 959
 960	opts->streaming_interval = 1;
 961	opts->streaming_maxpacket = 1024;
 962	snprintf(opts->function_name, sizeof(opts->function_name), "UVC Camera");
 963
 964	ret = uvcg_attach_configfs(opts);
 965	if (ret < 0) {
 966		kfree(opts);
 967		return ERR_PTR(ret);
 968	}
 969
 970	return &opts->func_inst;
 971}
 972
 973static void uvc_free(struct usb_function *f)
 974{
 975	struct uvc_device *uvc = to_uvc(f);
 976	struct f_uvc_opts *opts = container_of(f->fi, struct f_uvc_opts,
 977					       func_inst);
 978	if (!opts->header)
 979		config_item_put(&uvc->header->item);
 980	--opts->refcnt;
 981	kfree(uvc);
 982}
 983
 984static void uvc_function_unbind(struct usb_configuration *c,
 985				struct usb_function *f)
 986{
 987	struct usb_composite_dev *cdev = c->cdev;
 988	struct uvc_device *uvc = to_uvc(f);
 989	struct uvc_video *video = &uvc->video;
 990	long wait_ret = 1;
 991
 992	uvcg_info(f, "%s()\n", __func__);
 993
 994	if (video->async_wq)
 995		destroy_workqueue(video->async_wq);
 996
 997	/*
 998	 * If we know we're connected via v4l2, then there should be a cleanup
 999	 * of the device from userspace either via UVC_EVENT_DISCONNECT or
1000	 * though the video device removal uevent. Allow some time for the
1001	 * application to close out before things get deleted.
1002	 */
1003	if (uvc->func_connected) {
1004		uvcg_dbg(f, "waiting for clean disconnect\n");
1005		wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
1006				uvc->func_connected == false, msecs_to_jiffies(500));
1007		uvcg_dbg(f, "done waiting with ret: %ld\n", wait_ret);
1008	}
1009
1010	device_remove_file(&uvc->vdev.dev, &dev_attr_function_name);
1011	video_unregister_device(&uvc->vdev);
1012	v4l2_device_unregister(&uvc->v4l2_dev);
1013
1014	if (uvc->func_connected) {
1015		/*
1016		 * Wait for the release to occur to ensure there are no longer any
1017		 * pending operations that may cause panics when resources are cleaned
1018		 * up.
1019		 */
1020		uvcg_warn(f, "%s no clean disconnect, wait for release\n", __func__);
1021		wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
1022				uvc->func_connected == false, msecs_to_jiffies(1000));
1023		uvcg_dbg(f, "done waiting for release with ret: %ld\n", wait_ret);
1024	}
1025
1026	usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
1027	kfree(uvc->control_buf);
1028
1029	usb_free_all_descriptors(f);
1030}
1031
1032static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
1033{
1034	struct uvc_device *uvc;
1035	struct f_uvc_opts *opts;
1036	struct uvc_descriptor_header **strm_cls;
1037	struct config_item *streaming, *header, *h;
1038
1039	uvc = kzalloc(sizeof(*uvc), GFP_KERNEL);
1040	if (uvc == NULL)
1041		return ERR_PTR(-ENOMEM);
1042
1043	mutex_init(&uvc->video.mutex);
1044	uvc->state = UVC_STATE_DISCONNECTED;
1045	init_waitqueue_head(&uvc->func_connected_queue);
1046	opts = fi_to_f_uvc_opts(fi);
1047
1048	mutex_lock(&opts->lock);
1049	if (opts->uvc_fs_streaming_cls) {
1050		strm_cls = opts->uvc_fs_streaming_cls;
1051		opts->fs_streaming =
1052			(const struct uvc_descriptor_header * const *)strm_cls;
1053	}
1054	if (opts->uvc_hs_streaming_cls) {
1055		strm_cls = opts->uvc_hs_streaming_cls;
1056		opts->hs_streaming =
1057			(const struct uvc_descriptor_header * const *)strm_cls;
1058	}
1059	if (opts->uvc_ss_streaming_cls) {
1060		strm_cls = opts->uvc_ss_streaming_cls;
1061		opts->ss_streaming =
1062			(const struct uvc_descriptor_header * const *)strm_cls;
1063	}
1064
1065	uvc->desc.fs_control = opts->fs_control;
1066	uvc->desc.ss_control = opts->ss_control;
1067	uvc->desc.fs_streaming = opts->fs_streaming;
1068	uvc->desc.hs_streaming = opts->hs_streaming;
1069	uvc->desc.ss_streaming = opts->ss_streaming;
1070
1071	if (opts->header) {
1072		uvc->header = opts->header;
1073	} else {
1074		streaming = config_group_find_item(&opts->func_inst.group, "streaming");
1075		if (!streaming)
1076			goto err_config;
1077
1078		header = config_group_find_item(to_config_group(streaming), "header");
1079		config_item_put(streaming);
1080		if (!header)
1081			goto err_config;
1082
1083		h = config_group_find_item(to_config_group(header), "h");
1084		config_item_put(header);
1085		if (!h)
1086			goto err_config;
1087
1088		uvc->header = to_uvcg_streaming_header(h);
1089		if (!uvc->header->linked) {
1090			mutex_unlock(&opts->lock);
1091			kfree(uvc);
1092			return ERR_PTR(-EBUSY);
1093		}
1094	}
1095
1096	uvc->desc.extension_units = &opts->extension_units;
1097
1098	++opts->refcnt;
1099	mutex_unlock(&opts->lock);
1100
1101	/* Register the function. */
1102	uvc->func.name = "uvc";
1103	uvc->func.bind = uvc_function_bind;
1104	uvc->func.unbind = uvc_function_unbind;
1105	uvc->func.get_alt = uvc_function_get_alt;
1106	uvc->func.set_alt = uvc_function_set_alt;
1107	uvc->func.disable = uvc_function_disable;
1108	uvc->func.setup = uvc_function_setup;
1109	uvc->func.free_func = uvc_free;
1110	uvc->func.bind_deactivated = true;
1111
1112	return &uvc->func;
1113
1114err_config:
1115	mutex_unlock(&opts->lock);
1116	kfree(uvc);
1117	return ERR_PTR(-ENOENT);
1118}
1119
1120DECLARE_USB_FUNCTION_INIT(uvc, uvc_alloc_inst, uvc_alloc);
1121MODULE_LICENSE("GPL");
1122MODULE_AUTHOR("Laurent Pinchart");