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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * composite.c - infrastructure for Composite USB Gadgets
   4 *
   5 * Copyright (C) 2006-2008 David Brownell
   6 */
   7
   8/* #define VERBOSE_DEBUG */
   9
  10#include <linux/kallsyms.h>
  11#include <linux/kernel.h>
  12#include <linux/slab.h>
  13#include <linux/module.h>
  14#include <linux/device.h>
  15#include <linux/utsname.h>
  16#include <linux/bitfield.h>
  17#include <linux/uuid.h>
  18
  19#include <linux/usb/composite.h>
  20#include <linux/usb/otg.h>
  21#include <linux/usb/webusb.h>
  22#include <linux/unaligned.h>
  23
  24#include "u_os_desc.h"
  25
  26/**
  27 * struct usb_os_string - represents OS String to be reported by a gadget
  28 * @bLength: total length of the entire descritor, always 0x12
  29 * @bDescriptorType: USB_DT_STRING
  30 * @qwSignature: the OS String proper
  31 * @bMS_VendorCode: code used by the host for subsequent requests
  32 * @bPad: not used, must be zero
  33 */
  34struct usb_os_string {
  35	__u8	bLength;
  36	__u8	bDescriptorType;
  37	__u8	qwSignature[OS_STRING_QW_SIGN_LEN];
  38	__u8	bMS_VendorCode;
  39	__u8	bPad;
  40} __packed;
  41
  42/*
  43 * The code in this file is utility code, used to build a gadget driver
  44 * from one or more "function" drivers, one or more "configuration"
  45 * objects, and a "usb_composite_driver" by gluing them together along
  46 * with the relevant device-wide data.
  47 */
  48
  49static struct usb_gadget_strings **get_containers_gs(
  50		struct usb_gadget_string_container *uc)
  51{
  52	return (struct usb_gadget_strings **)uc->stash;
  53}
  54
  55/**
  56 * function_descriptors() - get function descriptors for speed
  57 * @f: the function
  58 * @speed: the speed
  59 *
  60 * Returns the descriptors or NULL if not set.
  61 */
  62static struct usb_descriptor_header **
  63function_descriptors(struct usb_function *f,
  64		     enum usb_device_speed speed)
  65{
  66	struct usb_descriptor_header **descriptors;
  67
  68	/*
  69	 * NOTE: we try to help gadget drivers which might not be setting
  70	 * max_speed appropriately.
  71	 */
  72
  73	switch (speed) {
  74	case USB_SPEED_SUPER_PLUS:
  75		descriptors = f->ssp_descriptors;
  76		if (descriptors)
  77			break;
  78		fallthrough;
  79	case USB_SPEED_SUPER:
  80		descriptors = f->ss_descriptors;
  81		if (descriptors)
  82			break;
  83		fallthrough;
  84	case USB_SPEED_HIGH:
  85		descriptors = f->hs_descriptors;
  86		if (descriptors)
  87			break;
  88		fallthrough;
  89	default:
  90		descriptors = f->fs_descriptors;
  91	}
  92
  93	/*
  94	 * if we can't find any descriptors at all, then this gadget deserves to
  95	 * Oops with a NULL pointer dereference
  96	 */
  97
  98	return descriptors;
  99}
 100
 101/**
 102 * next_desc() - advance to the next desc_type descriptor
 103 * @t: currect pointer within descriptor array
 104 * @desc_type: descriptor type
 105 *
 106 * Return: next desc_type descriptor or NULL
 107 *
 108 * Iterate over @t until either desc_type descriptor found or
 109 * NULL (that indicates end of list) encountered
 110 */
 111static struct usb_descriptor_header**
 112next_desc(struct usb_descriptor_header **t, u8 desc_type)
 113{
 114	for (; *t; t++) {
 115		if ((*t)->bDescriptorType == desc_type)
 116			return t;
 117	}
 118	return NULL;
 119}
 120
 121/*
 122 * for_each_desc() - iterate over desc_type descriptors in the
 123 * descriptors list
 124 * @start: pointer within descriptor array.
 125 * @iter_desc: desc_type descriptor to use as the loop cursor
 126 * @desc_type: wanted descriptr type
 127 */
 128#define for_each_desc(start, iter_desc, desc_type) \
 129	for (iter_desc = next_desc(start, desc_type); \
 130	     iter_desc; iter_desc = next_desc(iter_desc + 1, desc_type))
 131
 132/**
 133 * config_ep_by_speed_and_alt() - configures the given endpoint
 134 * according to gadget speed.
 135 * @g: pointer to the gadget
 136 * @f: usb function
 137 * @_ep: the endpoint to configure
 138 * @alt: alternate setting number
 139 *
 140 * Return: error code, 0 on success
 141 *
 142 * This function chooses the right descriptors for a given
 143 * endpoint according to gadget speed and saves it in the
 144 * endpoint desc field. If the endpoint already has a descriptor
 145 * assigned to it - overwrites it with currently corresponding
 146 * descriptor. The endpoint maxpacket field is updated according
 147 * to the chosen descriptor.
 148 * Note: the supplied function should hold all the descriptors
 149 * for supported speeds
 150 */
 151int config_ep_by_speed_and_alt(struct usb_gadget *g,
 152				struct usb_function *f,
 153				struct usb_ep *_ep,
 154				u8 alt)
 155{
 156	struct usb_endpoint_descriptor *chosen_desc = NULL;
 157	struct usb_interface_descriptor *int_desc = NULL;
 158	struct usb_descriptor_header **speed_desc = NULL;
 159
 160	struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 161	int want_comp_desc = 0;
 162
 163	struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 164	struct usb_composite_dev *cdev;
 165	bool incomplete_desc = false;
 166
 167	if (!g || !f || !_ep)
 168		return -EIO;
 169
 170	/* select desired speed */
 171	switch (g->speed) {
 172	case USB_SPEED_SUPER_PLUS:
 173		if (f->ssp_descriptors) {
 174			speed_desc = f->ssp_descriptors;
 175			want_comp_desc = 1;
 176			break;
 177		}
 178		incomplete_desc = true;
 179		fallthrough;
 180	case USB_SPEED_SUPER:
 181		if (f->ss_descriptors) {
 182			speed_desc = f->ss_descriptors;
 183			want_comp_desc = 1;
 184			break;
 185		}
 186		incomplete_desc = true;
 187		fallthrough;
 188	case USB_SPEED_HIGH:
 189		if (f->hs_descriptors) {
 190			speed_desc = f->hs_descriptors;
 191			break;
 192		}
 193		incomplete_desc = true;
 194		fallthrough;
 195	default:
 196		speed_desc = f->fs_descriptors;
 197	}
 198
 199	cdev = get_gadget_data(g);
 200	if (incomplete_desc)
 201		WARNING(cdev,
 202			"%s doesn't hold the descriptors for current speed\n",
 203			f->name);
 204
 205	/* find correct alternate setting descriptor */
 206	for_each_desc(speed_desc, d_spd, USB_DT_INTERFACE) {
 207		int_desc = (struct usb_interface_descriptor *)*d_spd;
 208
 209		if (int_desc->bAlternateSetting == alt) {
 210			speed_desc = d_spd;
 211			goto intf_found;
 212		}
 213	}
 214	return -EIO;
 215
 216intf_found:
 217	/* find descriptors */
 218	for_each_desc(speed_desc, d_spd, USB_DT_ENDPOINT) {
 219		chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 220		if (chosen_desc->bEndpointAddress == _ep->address)
 221			goto ep_found;
 222	}
 223	return -EIO;
 224
 225ep_found:
 226	/* commit results */
 227	_ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 228	_ep->desc = chosen_desc;
 229	_ep->comp_desc = NULL;
 230	_ep->maxburst = 0;
 231	_ep->mult = 1;
 232
 233	if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 234				usb_endpoint_xfer_int(_ep->desc)))
 235		_ep->mult = usb_endpoint_maxp_mult(_ep->desc);
 236
 237	if (!want_comp_desc)
 238		return 0;
 239
 240	/*
 241	 * Companion descriptor should follow EP descriptor
 242	 * USB 3.0 spec, #9.6.7
 243	 */
 244	comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 245	if (!comp_desc ||
 246	    (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 247		return -EIO;
 248	_ep->comp_desc = comp_desc;
 249	if (g->speed >= USB_SPEED_SUPER) {
 250		switch (usb_endpoint_type(_ep->desc)) {
 251		case USB_ENDPOINT_XFER_ISOC:
 252			/* mult: bits 1:0 of bmAttributes */
 253			_ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
 254			fallthrough;
 255		case USB_ENDPOINT_XFER_BULK:
 256		case USB_ENDPOINT_XFER_INT:
 257			_ep->maxburst = comp_desc->bMaxBurst + 1;
 258			break;
 259		default:
 260			if (comp_desc->bMaxBurst != 0)
 
 
 
 261				ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 
 262			_ep->maxburst = 1;
 263			break;
 264		}
 265	}
 266	return 0;
 267}
 268EXPORT_SYMBOL_GPL(config_ep_by_speed_and_alt);
 269
 270/**
 271 * config_ep_by_speed() - configures the given endpoint
 272 * according to gadget speed.
 273 * @g: pointer to the gadget
 274 * @f: usb function
 275 * @_ep: the endpoint to configure
 276 *
 277 * Return: error code, 0 on success
 278 *
 279 * This function chooses the right descriptors for a given
 280 * endpoint according to gadget speed and saves it in the
 281 * endpoint desc field. If the endpoint already has a descriptor
 282 * assigned to it - overwrites it with currently corresponding
 283 * descriptor. The endpoint maxpacket field is updated according
 284 * to the chosen descriptor.
 285 * Note: the supplied function should hold all the descriptors
 286 * for supported speeds
 287 */
 288int config_ep_by_speed(struct usb_gadget *g,
 289			struct usb_function *f,
 290			struct usb_ep *_ep)
 291{
 292	return config_ep_by_speed_and_alt(g, f, _ep, 0);
 293}
 294EXPORT_SYMBOL_GPL(config_ep_by_speed);
 295
 296/**
 297 * usb_add_function() - add a function to a configuration
 298 * @config: the configuration
 299 * @function: the function being added
 300 * Context: single threaded during gadget setup
 301 *
 302 * After initialization, each configuration must have one or more
 303 * functions added to it.  Adding a function involves calling its @bind()
 304 * method to allocate resources such as interface and string identifiers
 305 * and endpoints.
 306 *
 307 * This function returns the value of the function's bind(), which is
 308 * zero for success else a negative errno value.
 309 */
 310int usb_add_function(struct usb_configuration *config,
 311		struct usb_function *function)
 312{
 313	int	value = -EINVAL;
 314
 315	DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 316			function->name, function,
 317			config->label, config);
 318
 319	if (!function->set_alt || !function->disable)
 320		goto done;
 321
 322	function->config = config;
 323	list_add_tail(&function->list, &config->functions);
 324
 325	if (function->bind_deactivated) {
 326		value = usb_function_deactivate(function);
 327		if (value)
 328			goto done;
 329	}
 330
 331	/* REVISIT *require* function->bind? */
 332	if (function->bind) {
 333		value = function->bind(config, function);
 334		if (value < 0) {
 335			list_del(&function->list);
 336			function->config = NULL;
 337		}
 338	} else
 339		value = 0;
 340
 341	/* We allow configurations that don't work at both speeds.
 342	 * If we run into a lowspeed Linux system, treat it the same
 343	 * as full speed ... it's the function drivers that will need
 344	 * to avoid bulk and ISO transfers.
 345	 */
 346	if (!config->fullspeed && function->fs_descriptors)
 347		config->fullspeed = true;
 348	if (!config->highspeed && function->hs_descriptors)
 349		config->highspeed = true;
 350	if (!config->superspeed && function->ss_descriptors)
 351		config->superspeed = true;
 352	if (!config->superspeed_plus && function->ssp_descriptors)
 353		config->superspeed_plus = true;
 354
 355done:
 356	if (value)
 357		DBG(config->cdev, "adding '%s'/%p --> %d\n",
 358				function->name, function, value);
 359	return value;
 360}
 361EXPORT_SYMBOL_GPL(usb_add_function);
 362
 363void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 364{
 365	if (f->disable)
 366		f->disable(f);
 367
 368	bitmap_zero(f->endpoints, 32);
 369	list_del(&f->list);
 370	if (f->unbind)
 371		f->unbind(c, f);
 372
 373	if (f->bind_deactivated)
 374		usb_function_activate(f);
 375}
 376EXPORT_SYMBOL_GPL(usb_remove_function);
 377
 378/**
 379 * usb_function_deactivate - prevent function and gadget enumeration
 380 * @function: the function that isn't yet ready to respond
 381 *
 382 * Blocks response of the gadget driver to host enumeration by
 383 * preventing the data line pullup from being activated.  This is
 384 * normally called during @bind() processing to change from the
 385 * initial "ready to respond" state, or when a required resource
 386 * becomes available.
 387 *
 388 * For example, drivers that serve as a passthrough to a userspace
 389 * daemon can block enumeration unless that daemon (such as an OBEX,
 390 * MTP, or print server) is ready to handle host requests.
 391 *
 392 * Not all systems support software control of their USB peripheral
 393 * data pullups.
 394 *
 395 * Returns zero on success, else negative errno.
 396 */
 397int usb_function_deactivate(struct usb_function *function)
 398{
 399	struct usb_composite_dev	*cdev = function->config->cdev;
 400	unsigned long			flags;
 401	int				status = 0;
 402
 403	spin_lock_irqsave(&cdev->lock, flags);
 404
 405	if (cdev->deactivations == 0) {
 406		spin_unlock_irqrestore(&cdev->lock, flags);
 407		status = usb_gadget_deactivate(cdev->gadget);
 408		spin_lock_irqsave(&cdev->lock, flags);
 409	}
 410	if (status == 0)
 411		cdev->deactivations++;
 412
 413	spin_unlock_irqrestore(&cdev->lock, flags);
 414	return status;
 415}
 416EXPORT_SYMBOL_GPL(usb_function_deactivate);
 417
 418/**
 419 * usb_function_activate - allow function and gadget enumeration
 420 * @function: function on which usb_function_activate() was called
 421 *
 422 * Reverses effect of usb_function_deactivate().  If no more functions
 423 * are delaying their activation, the gadget driver will respond to
 424 * host enumeration procedures.
 425 *
 426 * Returns zero on success, else negative errno.
 427 */
 428int usb_function_activate(struct usb_function *function)
 429{
 430	struct usb_composite_dev	*cdev = function->config->cdev;
 431	unsigned long			flags;
 432	int				status = 0;
 433
 434	spin_lock_irqsave(&cdev->lock, flags);
 435
 436	if (WARN_ON(cdev->deactivations == 0))
 437		status = -EINVAL;
 438	else {
 439		cdev->deactivations--;
 440		if (cdev->deactivations == 0) {
 441			spin_unlock_irqrestore(&cdev->lock, flags);
 442			status = usb_gadget_activate(cdev->gadget);
 443			spin_lock_irqsave(&cdev->lock, flags);
 444		}
 445	}
 446
 447	spin_unlock_irqrestore(&cdev->lock, flags);
 448	return status;
 449}
 450EXPORT_SYMBOL_GPL(usb_function_activate);
 451
 452/**
 453 * usb_interface_id() - allocate an unused interface ID
 454 * @config: configuration associated with the interface
 455 * @function: function handling the interface
 456 * Context: single threaded during gadget setup
 457 *
 458 * usb_interface_id() is called from usb_function.bind() callbacks to
 459 * allocate new interface IDs.  The function driver will then store that
 460 * ID in interface, association, CDC union, and other descriptors.  It
 461 * will also handle any control requests targeted at that interface,
 462 * particularly changing its altsetting via set_alt().  There may
 463 * also be class-specific or vendor-specific requests to handle.
 464 *
 465 * All interface identifier should be allocated using this routine, to
 466 * ensure that for example different functions don't wrongly assign
 467 * different meanings to the same identifier.  Note that since interface
 468 * identifiers are configuration-specific, functions used in more than
 469 * one configuration (or more than once in a given configuration) need
 470 * multiple versions of the relevant descriptors.
 471 *
 472 * Returns the interface ID which was allocated; or -ENODEV if no
 473 * more interface IDs can be allocated.
 474 */
 475int usb_interface_id(struct usb_configuration *config,
 476		struct usb_function *function)
 477{
 478	unsigned id = config->next_interface_id;
 479
 480	if (id < MAX_CONFIG_INTERFACES) {
 481		config->interface[id] = function;
 482		config->next_interface_id = id + 1;
 483		return id;
 484	}
 485	return -ENODEV;
 486}
 487EXPORT_SYMBOL_GPL(usb_interface_id);
 488
 489/**
 490 * usb_func_wakeup - sends function wake notification to the host.
 491 * @func: function that sends the remote wakeup notification.
 492 *
 493 * Applicable to devices operating at enhanced superspeed when usb
 494 * functions are put in function suspend state and armed for function
 495 * remote wakeup. On completion, function wake notification is sent. If
 496 * the device is in low power state it tries to bring the device to active
 497 * state before sending the wake notification. Since it is a synchronous
 498 * call, caller must take care of not calling it in interrupt context.
 499 * For devices operating at lower speeds  returns negative errno.
 500 *
 501 * Returns zero on success, else negative errno.
 502 */
 503int usb_func_wakeup(struct usb_function *func)
 504{
 505	struct usb_gadget	*gadget = func->config->cdev->gadget;
 506	int			id;
 507
 508	if (!gadget->ops->func_wakeup)
 509		return -EOPNOTSUPP;
 510
 511	if (!func->func_wakeup_armed) {
 512		ERROR(func->config->cdev, "not armed for func remote wakeup\n");
 513		return -EINVAL;
 514	}
 515
 516	for (id = 0; id < MAX_CONFIG_INTERFACES; id++)
 517		if (func->config->interface[id] == func)
 518			break;
 519
 520	if (id == MAX_CONFIG_INTERFACES) {
 521		ERROR(func->config->cdev, "Invalid function\n");
 522		return -EINVAL;
 523	}
 524
 525	return gadget->ops->func_wakeup(gadget, id);
 526}
 527EXPORT_SYMBOL_GPL(usb_func_wakeup);
 528
 529static u8 encode_bMaxPower(enum usb_device_speed speed,
 530		struct usb_configuration *c)
 531{
 532	unsigned val;
 533
 534	if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
 535		val = c->MaxPower;
 536	else
 537		val = CONFIG_USB_GADGET_VBUS_DRAW;
 538	if (!val)
 539		return 0;
 540	if (speed < USB_SPEED_SUPER)
 541		return min(val, 500U) / 2;
 542	else
 543		/*
 544		 * USB 3.x supports up to 900mA, but since 900 isn't divisible
 545		 * by 8 the integral division will effectively cap to 896mA.
 546		 */
 547		return min(val, 900U) / 8;
 548}
 549
 550void check_remote_wakeup_config(struct usb_gadget *g,
 551				struct usb_configuration *c)
 552{
 553	if (USB_CONFIG_ATT_WAKEUP & c->bmAttributes) {
 554		/* Reset the rw bit if gadget is not capable of it */
 555		if (!g->wakeup_capable && g->ops->set_remote_wakeup) {
 556			WARN(c->cdev, "Clearing wakeup bit for config c.%d\n",
 557			     c->bConfigurationValue);
 558			c->bmAttributes &= ~USB_CONFIG_ATT_WAKEUP;
 559		}
 560	}
 561}
 562
 563static int config_buf(struct usb_configuration *config,
 564		enum usb_device_speed speed, void *buf, u8 type)
 565{
 566	struct usb_config_descriptor	*c = buf;
 567	void				*next = buf + USB_DT_CONFIG_SIZE;
 568	int				len;
 569	struct usb_function		*f;
 570	int				status;
 571
 572	len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 573	/* write the config descriptor */
 574	c = buf;
 575	c->bLength = USB_DT_CONFIG_SIZE;
 576	c->bDescriptorType = type;
 577	/* wTotalLength is written later */
 578	c->bNumInterfaces = config->next_interface_id;
 579	c->bConfigurationValue = config->bConfigurationValue;
 580	c->iConfiguration = config->iConfiguration;
 581	c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 582	c->bMaxPower = encode_bMaxPower(speed, config);
 583
 584	/* There may be e.g. OTG descriptors */
 585	if (config->descriptors) {
 586		status = usb_descriptor_fillbuf(next, len,
 587				config->descriptors);
 588		if (status < 0)
 589			return status;
 590		len -= status;
 591		next += status;
 592	}
 593
 594	/* add each function's descriptors */
 595	list_for_each_entry(f, &config->functions, list) {
 596		struct usb_descriptor_header **descriptors;
 597
 598		descriptors = function_descriptors(f, speed);
 599		if (!descriptors)
 600			continue;
 601		status = usb_descriptor_fillbuf(next, len,
 602			(const struct usb_descriptor_header **) descriptors);
 603		if (status < 0)
 604			return status;
 605		len -= status;
 606		next += status;
 607	}
 608
 609	len = next - buf;
 610	c->wTotalLength = cpu_to_le16(len);
 611	return len;
 612}
 613
 614static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 615{
 616	struct usb_gadget		*gadget = cdev->gadget;
 617	struct usb_configuration	*c;
 618	struct list_head		*pos;
 619	u8				type = w_value >> 8;
 620	enum usb_device_speed		speed = USB_SPEED_UNKNOWN;
 621
 622	if (gadget->speed >= USB_SPEED_SUPER)
 623		speed = gadget->speed;
 624	else if (gadget_is_dualspeed(gadget)) {
 625		int	hs = 0;
 626		if (gadget->speed == USB_SPEED_HIGH)
 627			hs = 1;
 628		if (type == USB_DT_OTHER_SPEED_CONFIG)
 629			hs = !hs;
 630		if (hs)
 631			speed = USB_SPEED_HIGH;
 632
 633	}
 634
 635	/* This is a lookup by config *INDEX* */
 636	w_value &= 0xff;
 637
 638	pos = &cdev->configs;
 639	c = cdev->os_desc_config;
 640	if (c)
 641		goto check_config;
 642
 643	while ((pos = pos->next) !=  &cdev->configs) {
 644		c = list_entry(pos, typeof(*c), list);
 645
 646		/* skip OS Descriptors config which is handled separately */
 647		if (c == cdev->os_desc_config)
 648			continue;
 649
 650check_config:
 651		/* ignore configs that won't work at this speed */
 652		switch (speed) {
 653		case USB_SPEED_SUPER_PLUS:
 654			if (!c->superspeed_plus)
 655				continue;
 656			break;
 657		case USB_SPEED_SUPER:
 658			if (!c->superspeed)
 659				continue;
 660			break;
 661		case USB_SPEED_HIGH:
 662			if (!c->highspeed)
 663				continue;
 664			break;
 665		default:
 666			if (!c->fullspeed)
 667				continue;
 668		}
 669
 670		if (w_value == 0)
 671			return config_buf(c, speed, cdev->req->buf, type);
 672		w_value--;
 673	}
 674	return -EINVAL;
 675}
 676
 677static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 678{
 679	struct usb_gadget		*gadget = cdev->gadget;
 680	struct usb_configuration	*c;
 681	unsigned			count = 0;
 682	int				hs = 0;
 683	int				ss = 0;
 684	int				ssp = 0;
 685
 686	if (gadget_is_dualspeed(gadget)) {
 687		if (gadget->speed == USB_SPEED_HIGH)
 688			hs = 1;
 689		if (gadget->speed == USB_SPEED_SUPER)
 690			ss = 1;
 691		if (gadget->speed == USB_SPEED_SUPER_PLUS)
 692			ssp = 1;
 693		if (type == USB_DT_DEVICE_QUALIFIER)
 694			hs = !hs;
 695	}
 696	list_for_each_entry(c, &cdev->configs, list) {
 697		/* ignore configs that won't work at this speed */
 698		if (ssp) {
 699			if (!c->superspeed_plus)
 700				continue;
 701		} else if (ss) {
 702			if (!c->superspeed)
 703				continue;
 704		} else if (hs) {
 705			if (!c->highspeed)
 706				continue;
 707		} else {
 708			if (!c->fullspeed)
 709				continue;
 710		}
 711		count++;
 712	}
 713	return count;
 714}
 715
 716/**
 717 * bos_desc() - prepares the BOS descriptor.
 718 * @cdev: pointer to usb_composite device to generate the bos
 719 *	descriptor for
 720 *
 721 * This function generates the BOS (Binary Device Object)
 722 * descriptor and its device capabilities descriptors. The BOS
 723 * descriptor should be supported by a SuperSpeed device.
 724 */
 725static int bos_desc(struct usb_composite_dev *cdev)
 726{
 727	struct usb_ext_cap_descriptor	*usb_ext;
 728	struct usb_dcd_config_params	dcd_config_params;
 729	struct usb_bos_descriptor	*bos = cdev->req->buf;
 730	unsigned int			besl = 0;
 731
 732	bos->bLength = USB_DT_BOS_SIZE;
 733	bos->bDescriptorType = USB_DT_BOS;
 734
 735	bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 736	bos->bNumDeviceCaps = 0;
 737
 738	/* Get Controller configuration */
 739	if (cdev->gadget->ops->get_config_params) {
 740		cdev->gadget->ops->get_config_params(cdev->gadget,
 741						     &dcd_config_params);
 742	} else {
 743		dcd_config_params.besl_baseline =
 744			USB_DEFAULT_BESL_UNSPECIFIED;
 745		dcd_config_params.besl_deep =
 746			USB_DEFAULT_BESL_UNSPECIFIED;
 747		dcd_config_params.bU1devExitLat =
 748			USB_DEFAULT_U1_DEV_EXIT_LAT;
 749		dcd_config_params.bU2DevExitLat =
 750			cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 751	}
 752
 753	if (dcd_config_params.besl_baseline != USB_DEFAULT_BESL_UNSPECIFIED)
 754		besl = USB_BESL_BASELINE_VALID |
 755			USB_SET_BESL_BASELINE(dcd_config_params.besl_baseline);
 756
 757	if (dcd_config_params.besl_deep != USB_DEFAULT_BESL_UNSPECIFIED)
 758		besl |= USB_BESL_DEEP_VALID |
 759			USB_SET_BESL_DEEP(dcd_config_params.besl_deep);
 760
 761	/*
 762	 * A SuperSpeed device shall include the USB2.0 extension descriptor
 763	 * and shall support LPM when operating in USB2.0 HS mode.
 764	 */
 765	if (cdev->gadget->lpm_capable) {
 766		usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 767		bos->bNumDeviceCaps++;
 768		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 769		usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 770		usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 771		usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 772		usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
 773							USB_BESL_SUPPORT | besl);
 774	}
 775
 776	/*
 777	 * The Superspeed USB Capability descriptor shall be implemented by all
 778	 * SuperSpeed devices.
 779	 */
 780	if (gadget_is_superspeed(cdev->gadget)) {
 781		struct usb_ss_cap_descriptor *ss_cap;
 782
 783		ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 784		bos->bNumDeviceCaps++;
 785		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 786		ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 787		ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 788		ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 789		ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 790		ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 791						      USB_FULL_SPEED_OPERATION |
 792						      USB_HIGH_SPEED_OPERATION |
 793						      USB_5GBPS_OPERATION);
 794		ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 795		ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 796		ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 797	}
 798
 799	/* The SuperSpeedPlus USB Device Capability descriptor */
 800	if (gadget_is_superspeed_plus(cdev->gadget)) {
 801		struct usb_ssp_cap_descriptor *ssp_cap;
 802		u8 ssac = 1;
 803		u8 ssic;
 804		int i;
 805
 806		if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x2)
 807			ssac = 3;
 808
 809		/*
 810		 * Paired RX and TX sublink speed attributes share
 811		 * the same SSID.
 812		 */
 813		ssic = (ssac + 1) / 2 - 1;
 814
 815		ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 816		bos->bNumDeviceCaps++;
 817
 818		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(ssac));
 819		ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(ssac);
 820		ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 821		ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 822		ssp_cap->bReserved = 0;
 823		ssp_cap->wReserved = 0;
 824
 825		ssp_cap->bmAttributes =
 826			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, ssac) |
 827				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, ssic));
 828
 829		ssp_cap->wFunctionalitySupport =
 830			cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, 0) |
 831				    FIELD_PREP(USB_SSP_MIN_RX_LANE_COUNT, 1) |
 832				    FIELD_PREP(USB_SSP_MIN_TX_LANE_COUNT, 1));
 833
 834		/*
 835		 * Use 1 SSID if the gadget supports up to gen2x1 or not
 836		 * specified:
 837		 * - SSID 0 for symmetric RX/TX sublink speed of 10 Gbps.
 838		 *
 839		 * Use 1 SSID if the gadget supports up to gen1x2:
 840		 * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
 841		 *
 842		 * Use 2 SSIDs if the gadget supports up to gen2x2:
 843		 * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
 844		 * - SSID 1 for symmetric RX/TX sublink speed of 10 Gbps.
 845		 */
 846		for (i = 0; i < ssac + 1; i++) {
 847			u8 ssid;
 848			u8 mantissa;
 849			u8 type;
 850
 851			ssid = i >> 1;
 852
 853			if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x1 ||
 854			    cdev->gadget->max_ssp_rate == USB_SSP_GEN_UNKNOWN)
 855				mantissa = 10;
 856			else
 857				mantissa = 5 << ssid;
 858
 859			if (i % 2)
 860				type = USB_SSP_SUBLINK_SPEED_ST_SYM_TX;
 861			else
 862				type = USB_SSP_SUBLINK_SPEED_ST_SYM_RX;
 863
 864			ssp_cap->bmSublinkSpeedAttr[i] =
 865				cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, ssid) |
 866					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE,
 867						       USB_SSP_SUBLINK_SPEED_LSE_GBPS) |
 868					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST, type) |
 869					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP,
 870						       USB_SSP_SUBLINK_SPEED_LP_SSP) |
 871					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, mantissa));
 872		}
 873	}
 874
 875	/* The WebUSB Platform Capability descriptor */
 876	if (cdev->use_webusb) {
 877		struct usb_plat_dev_cap_descriptor *webusb_cap;
 878		struct usb_webusb_cap_data *webusb_cap_data;
 879		guid_t webusb_uuid = WEBUSB_UUID;
 880
 881		webusb_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 882		webusb_cap_data = (struct usb_webusb_cap_data *) webusb_cap->CapabilityData;
 883		bos->bNumDeviceCaps++;
 884		le16_add_cpu(&bos->wTotalLength,
 885			USB_DT_USB_PLAT_DEV_CAP_SIZE(USB_WEBUSB_CAP_DATA_SIZE));
 886
 887		webusb_cap->bLength = USB_DT_USB_PLAT_DEV_CAP_SIZE(USB_WEBUSB_CAP_DATA_SIZE);
 888		webusb_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 889		webusb_cap->bDevCapabilityType = USB_PLAT_DEV_CAP_TYPE;
 890		webusb_cap->bReserved = 0;
 891		export_guid(webusb_cap->UUID, &webusb_uuid);
 892
 893		if (cdev->bcd_webusb_version != 0)
 894			webusb_cap_data->bcdVersion = cpu_to_le16(cdev->bcd_webusb_version);
 895		else
 896			webusb_cap_data->bcdVersion = WEBUSB_VERSION_1_00;
 897
 898		webusb_cap_data->bVendorCode = cdev->b_webusb_vendor_code;
 899
 900		if (strnlen(cdev->landing_page, sizeof(cdev->landing_page)) > 0)
 901			webusb_cap_data->iLandingPage = WEBUSB_LANDING_PAGE_PRESENT;
 902		else
 903			webusb_cap_data->iLandingPage = WEBUSB_LANDING_PAGE_NOT_PRESENT;
 904	}
 905
 906	return le16_to_cpu(bos->wTotalLength);
 907}
 908
 909static void device_qual(struct usb_composite_dev *cdev)
 910{
 911	struct usb_qualifier_descriptor	*qual = cdev->req->buf;
 912
 913	qual->bLength = sizeof(*qual);
 914	qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 915	/* POLICY: same bcdUSB and device type info at both speeds */
 916	qual->bcdUSB = cdev->desc.bcdUSB;
 917	qual->bDeviceClass = cdev->desc.bDeviceClass;
 918	qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 919	qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 920	/* ASSUME same EP0 fifo size at both speeds */
 921	qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 922	qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 923	qual->bRESERVED = 0;
 924}
 925
 926/*-------------------------------------------------------------------------*/
 927
 928static void reset_config(struct usb_composite_dev *cdev)
 929{
 930	struct usb_function		*f;
 931
 932	DBG(cdev, "reset config\n");
 933
 934	list_for_each_entry(f, &cdev->config->functions, list) {
 935		if (f->disable)
 936			f->disable(f);
 937
 938		/* Section 9.1.1.6, disable remote wakeup when device is reset */
 939		f->func_wakeup_armed = false;
 940
 941		bitmap_zero(f->endpoints, 32);
 942	}
 943	cdev->config = NULL;
 944	cdev->delayed_status = 0;
 945}
 946
 947static int set_config(struct usb_composite_dev *cdev,
 948		const struct usb_ctrlrequest *ctrl, unsigned number)
 949{
 950	struct usb_gadget	*gadget = cdev->gadget;
 951	struct usb_configuration *c = NULL, *iter;
 952	int			result = -EINVAL;
 953	unsigned		power = gadget_is_otg(gadget) ? 8 : 100;
 954	int			tmp;
 955
 956	if (number) {
 957		list_for_each_entry(iter, &cdev->configs, list) {
 958			if (iter->bConfigurationValue != number)
 959				continue;
 960			/*
 961			 * We disable the FDs of the previous
 962			 * configuration only if the new configuration
 963			 * is a valid one
 964			 */
 965			if (cdev->config)
 966				reset_config(cdev);
 967			c = iter;
 968			result = 0;
 969			break;
 970		}
 971		if (result < 0)
 972			goto done;
 973	} else { /* Zero configuration value - need to reset the config */
 974		if (cdev->config)
 975			reset_config(cdev);
 976		result = 0;
 977	}
 978
 979	DBG(cdev, "%s config #%d: %s\n",
 980	    usb_speed_string(gadget->speed),
 981	    number, c ? c->label : "unconfigured");
 982
 983	if (!c)
 984		goto done;
 985
 986	usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 987	cdev->config = c;
 988
 989	/* Initialize all interfaces by setting them to altsetting zero. */
 990	for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 991		struct usb_function	*f = c->interface[tmp];
 992		struct usb_descriptor_header **descriptors;
 993
 994		if (!f)
 995			break;
 996
 997		/*
 998		 * Record which endpoints are used by the function. This is used
 999		 * to dispatch control requests targeted at that endpoint to the
1000		 * function's setup callback instead of the current
1001		 * configuration's setup callback.
1002		 */
1003		descriptors = function_descriptors(f, gadget->speed);
1004
1005		for (; *descriptors; ++descriptors) {
1006			struct usb_endpoint_descriptor *ep;
1007			int addr;
1008
1009			if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
1010				continue;
1011
1012			ep = (struct usb_endpoint_descriptor *)*descriptors;
1013			addr = ((ep->bEndpointAddress & 0x80) >> 3)
1014			     |  (ep->bEndpointAddress & 0x0f);
1015			set_bit(addr, f->endpoints);
1016		}
1017
1018		result = f->set_alt(f, tmp, 0);
1019		if (result < 0) {
1020			DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
1021					tmp, f->name, f, result);
1022
1023			reset_config(cdev);
1024			goto done;
1025		}
1026
1027		if (result == USB_GADGET_DELAYED_STATUS) {
1028			DBG(cdev,
1029			 "%s: interface %d (%s) requested delayed status\n",
1030					__func__, tmp, f->name);
1031			cdev->delayed_status++;
1032			DBG(cdev, "delayed_status count %d\n",
1033					cdev->delayed_status);
1034		}
1035	}
1036
1037	/* when we return, be sure our power usage is valid */
1038	if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
1039		power = c->MaxPower;
1040	else
1041		power = CONFIG_USB_GADGET_VBUS_DRAW;
1042
1043	if (gadget->speed < USB_SPEED_SUPER)
1044		power = min(power, 500U);
1045	else
1046		power = min(power, 900U);
1047
1048	if (USB_CONFIG_ATT_WAKEUP & c->bmAttributes)
1049		usb_gadget_set_remote_wakeup(gadget, 1);
1050	else
1051		usb_gadget_set_remote_wakeup(gadget, 0);
1052done:
1053	if (power > USB_SELF_POWER_VBUS_MAX_DRAW ||
1054	    (c && !(c->bmAttributes & USB_CONFIG_ATT_SELFPOWER)))
1055		usb_gadget_clear_selfpowered(gadget);
1056	else
1057		usb_gadget_set_selfpowered(gadget);
 
 
1058
1059	usb_gadget_vbus_draw(gadget, power);
1060	if (result >= 0 && cdev->delayed_status)
1061		result = USB_GADGET_DELAYED_STATUS;
1062	return result;
1063}
1064
1065int usb_add_config_only(struct usb_composite_dev *cdev,
1066		struct usb_configuration *config)
1067{
1068	struct usb_configuration *c;
1069
1070	if (!config->bConfigurationValue)
1071		return -EINVAL;
1072
1073	/* Prevent duplicate configuration identifiers */
1074	list_for_each_entry(c, &cdev->configs, list) {
1075		if (c->bConfigurationValue == config->bConfigurationValue)
1076			return -EBUSY;
1077	}
1078
1079	config->cdev = cdev;
1080	list_add_tail(&config->list, &cdev->configs);
1081
1082	INIT_LIST_HEAD(&config->functions);
1083	config->next_interface_id = 0;
1084	memset(config->interface, 0, sizeof(config->interface));
1085
1086	return 0;
1087}
1088EXPORT_SYMBOL_GPL(usb_add_config_only);
1089
1090/**
1091 * usb_add_config() - add a configuration to a device.
1092 * @cdev: wraps the USB gadget
1093 * @config: the configuration, with bConfigurationValue assigned
1094 * @bind: the configuration's bind function
1095 * Context: single threaded during gadget setup
1096 *
1097 * One of the main tasks of a composite @bind() routine is to
1098 * add each of the configurations it supports, using this routine.
1099 *
1100 * This function returns the value of the configuration's @bind(), which
1101 * is zero for success else a negative errno value.  Binding configurations
1102 * assigns global resources including string IDs, and per-configuration
1103 * resources such as interface IDs and endpoints.
1104 */
1105int usb_add_config(struct usb_composite_dev *cdev,
1106		struct usb_configuration *config,
1107		int (*bind)(struct usb_configuration *))
1108{
1109	int				status = -EINVAL;
1110
1111	if (!bind)
1112		goto done;
1113
1114	DBG(cdev, "adding config #%u '%s'/%p\n",
1115			config->bConfigurationValue,
1116			config->label, config);
1117
1118	status = usb_add_config_only(cdev, config);
1119	if (status)
1120		goto done;
1121
1122	status = bind(config);
1123
1124	if (status == 0)
1125		status = usb_gadget_check_config(cdev->gadget);
1126
1127	if (status < 0) {
1128		while (!list_empty(&config->functions)) {
1129			struct usb_function		*f;
1130
1131			f = list_first_entry(&config->functions,
1132					struct usb_function, list);
1133			list_del(&f->list);
1134			if (f->unbind) {
1135				DBG(cdev, "unbind function '%s'/%p\n",
1136					f->name, f);
1137				f->unbind(config, f);
1138				/* may free memory for "f" */
1139			}
1140		}
1141		list_del(&config->list);
1142		config->cdev = NULL;
1143	} else {
1144		unsigned	i;
1145
1146		DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
1147			config->bConfigurationValue, config,
1148			config->superspeed_plus ? " superplus" : "",
1149			config->superspeed ? " super" : "",
1150			config->highspeed ? " high" : "",
1151			config->fullspeed
1152				? (gadget_is_dualspeed(cdev->gadget)
1153					? " full"
1154					: " full/low")
1155				: "");
1156
1157		for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
1158			struct usb_function	*f = config->interface[i];
1159
1160			if (!f)
1161				continue;
1162			DBG(cdev, "  interface %d = %s/%p\n",
1163				i, f->name, f);
1164		}
1165	}
1166
1167	/* set_alt(), or next bind(), sets up ep->claimed as needed */
1168	usb_ep_autoconfig_reset(cdev->gadget);
1169
1170done:
1171	if (status)
1172		DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
1173				config->bConfigurationValue, status);
1174	return status;
1175}
1176EXPORT_SYMBOL_GPL(usb_add_config);
1177
1178static void remove_config(struct usb_composite_dev *cdev,
1179			      struct usb_configuration *config)
1180{
1181	while (!list_empty(&config->functions)) {
1182		struct usb_function		*f;
1183
1184		f = list_first_entry(&config->functions,
1185				struct usb_function, list);
1186
1187		usb_remove_function(config, f);
1188	}
1189	list_del(&config->list);
1190	if (config->unbind) {
1191		DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
1192		config->unbind(config);
1193			/* may free memory for "c" */
1194	}
1195}
1196
1197/**
1198 * usb_remove_config() - remove a configuration from a device.
1199 * @cdev: wraps the USB gadget
1200 * @config: the configuration
1201 *
1202 * Drivers must call usb_gadget_disconnect before calling this function
1203 * to disconnect the device from the host and make sure the host will not
1204 * try to enumerate the device while we are changing the config list.
1205 */
1206void usb_remove_config(struct usb_composite_dev *cdev,
1207		      struct usb_configuration *config)
1208{
1209	unsigned long flags;
1210
1211	spin_lock_irqsave(&cdev->lock, flags);
1212
1213	if (cdev->config == config)
1214		reset_config(cdev);
1215
1216	spin_unlock_irqrestore(&cdev->lock, flags);
1217
1218	remove_config(cdev, config);
1219}
1220
1221/*-------------------------------------------------------------------------*/
1222
1223/* We support strings in multiple languages ... string descriptor zero
1224 * says which languages are supported.  The typical case will be that
1225 * only one language (probably English) is used, with i18n handled on
1226 * the host side.
1227 */
1228
1229static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1230{
1231	const struct usb_gadget_strings	*s;
1232	__le16				language;
1233	__le16				*tmp;
1234
1235	while (*sp) {
1236		s = *sp;
1237		language = cpu_to_le16(s->language);
1238		for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) {
1239			if (*tmp == language)
1240				goto repeat;
1241		}
1242		*tmp++ = language;
1243repeat:
1244		sp++;
1245	}
1246}
1247
1248static int lookup_string(
1249	struct usb_gadget_strings	**sp,
1250	void				*buf,
1251	u16				language,
1252	int				id
1253)
1254{
1255	struct usb_gadget_strings	*s;
1256	int				value;
1257
1258	while (*sp) {
1259		s = *sp++;
1260		if (s->language != language)
1261			continue;
1262		value = usb_gadget_get_string(s, id, buf);
1263		if (value > 0)
1264			return value;
1265	}
1266	return -EINVAL;
1267}
1268
1269static int get_string(struct usb_composite_dev *cdev,
1270		void *buf, u16 language, int id)
1271{
1272	struct usb_composite_driver	*composite = cdev->driver;
1273	struct usb_gadget_string_container *uc;
1274	struct usb_configuration	*c;
1275	struct usb_function		*f;
1276	int				len;
1277
1278	/* Yes, not only is USB's i18n support probably more than most
1279	 * folk will ever care about ... also, it's all supported here.
1280	 * (Except for UTF8 support for Unicode's "Astral Planes".)
1281	 */
1282
1283	/* 0 == report all available language codes */
1284	if (id == 0) {
1285		struct usb_string_descriptor	*s = buf;
1286		struct usb_gadget_strings	**sp;
1287
1288		memset(s, 0, 256);
1289		s->bDescriptorType = USB_DT_STRING;
1290
1291		sp = composite->strings;
1292		if (sp)
1293			collect_langs(sp, s->wData);
1294
1295		list_for_each_entry(c, &cdev->configs, list) {
1296			sp = c->strings;
1297			if (sp)
1298				collect_langs(sp, s->wData);
1299
1300			list_for_each_entry(f, &c->functions, list) {
1301				sp = f->strings;
1302				if (sp)
1303					collect_langs(sp, s->wData);
1304			}
1305		}
1306		list_for_each_entry(uc, &cdev->gstrings, list) {
1307			struct usb_gadget_strings **sp;
1308
1309			sp = get_containers_gs(uc);
1310			collect_langs(sp, s->wData);
1311		}
1312
1313		for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++)
1314			continue;
1315		if (!len)
1316			return -EINVAL;
1317
1318		s->bLength = 2 * (len + 1);
1319		return s->bLength;
1320	}
1321
1322	if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1323		struct usb_os_string *b = buf;
1324		b->bLength = sizeof(*b);
1325		b->bDescriptorType = USB_DT_STRING;
1326		compiletime_assert(
1327			sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1328			"qwSignature size must be equal to qw_sign");
1329		memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1330		b->bMS_VendorCode = cdev->b_vendor_code;
1331		b->bPad = 0;
1332		return sizeof(*b);
1333	}
1334
1335	list_for_each_entry(uc, &cdev->gstrings, list) {
1336		struct usb_gadget_strings **sp;
1337
1338		sp = get_containers_gs(uc);
1339		len = lookup_string(sp, buf, language, id);
1340		if (len > 0)
1341			return len;
1342	}
1343
1344	/* String IDs are device-scoped, so we look up each string
1345	 * table we're told about.  These lookups are infrequent;
1346	 * simpler-is-better here.
1347	 */
1348	if (composite->strings) {
1349		len = lookup_string(composite->strings, buf, language, id);
1350		if (len > 0)
1351			return len;
1352	}
1353	list_for_each_entry(c, &cdev->configs, list) {
1354		if (c->strings) {
1355			len = lookup_string(c->strings, buf, language, id);
1356			if (len > 0)
1357				return len;
1358		}
1359		list_for_each_entry(f, &c->functions, list) {
1360			if (!f->strings)
1361				continue;
1362			len = lookup_string(f->strings, buf, language, id);
1363			if (len > 0)
1364				return len;
1365		}
1366	}
1367	return -EINVAL;
1368}
1369
1370/**
1371 * usb_string_id() - allocate an unused string ID
1372 * @cdev: the device whose string descriptor IDs are being allocated
1373 * Context: single threaded during gadget setup
1374 *
1375 * @usb_string_id() is called from bind() callbacks to allocate
1376 * string IDs.  Drivers for functions, configurations, or gadgets will
1377 * then store that ID in the appropriate descriptors and string table.
1378 *
1379 * All string identifier should be allocated using this,
1380 * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1381 * that for example different functions don't wrongly assign different
1382 * meanings to the same identifier.
1383 */
1384int usb_string_id(struct usb_composite_dev *cdev)
1385{
1386	if (cdev->next_string_id < 254) {
1387		/* string id 0 is reserved by USB spec for list of
1388		 * supported languages */
1389		/* 255 reserved as well? -- mina86 */
1390		cdev->next_string_id++;
1391		return cdev->next_string_id;
1392	}
1393	return -ENODEV;
1394}
1395EXPORT_SYMBOL_GPL(usb_string_id);
1396
1397/**
1398 * usb_string_ids_tab() - allocate unused string IDs in batch
1399 * @cdev: the device whose string descriptor IDs are being allocated
1400 * @str: an array of usb_string objects to assign numbers to
1401 * Context: single threaded during gadget setup
1402 *
1403 * @usb_string_ids() is called from bind() callbacks to allocate
1404 * string IDs.  Drivers for functions, configurations, or gadgets will
1405 * then copy IDs from the string table to the appropriate descriptors
1406 * and string table for other languages.
1407 *
1408 * All string identifier should be allocated using this,
1409 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1410 * example different functions don't wrongly assign different meanings
1411 * to the same identifier.
1412 */
1413int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1414{
1415	int next = cdev->next_string_id;
1416
1417	for (; str->s; ++str) {
1418		if (unlikely(next >= 254))
1419			return -ENODEV;
1420		str->id = ++next;
1421	}
1422
1423	cdev->next_string_id = next;
1424
1425	return 0;
1426}
1427EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1428
1429static struct usb_gadget_string_container *copy_gadget_strings(
1430		struct usb_gadget_strings **sp, unsigned n_gstrings,
1431		unsigned n_strings)
1432{
1433	struct usb_gadget_string_container *uc;
1434	struct usb_gadget_strings **gs_array;
1435	struct usb_gadget_strings *gs;
1436	struct usb_string *s;
1437	unsigned mem;
1438	unsigned n_gs;
1439	unsigned n_s;
1440	void *stash;
1441
1442	mem = sizeof(*uc);
1443	mem += sizeof(void *) * (n_gstrings + 1);
1444	mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1445	mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1446	uc = kmalloc(mem, GFP_KERNEL);
1447	if (!uc)
1448		return ERR_PTR(-ENOMEM);
1449	gs_array = get_containers_gs(uc);
1450	stash = uc->stash;
1451	stash += sizeof(void *) * (n_gstrings + 1);
1452	for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1453		struct usb_string *org_s;
1454
1455		gs_array[n_gs] = stash;
1456		gs = gs_array[n_gs];
1457		stash += sizeof(struct usb_gadget_strings);
1458		gs->language = sp[n_gs]->language;
1459		gs->strings = stash;
1460		org_s = sp[n_gs]->strings;
1461
1462		for (n_s = 0; n_s < n_strings; n_s++) {
1463			s = stash;
1464			stash += sizeof(struct usb_string);
1465			if (org_s->s)
1466				s->s = org_s->s;
1467			else
1468				s->s = "";
1469			org_s++;
1470		}
1471		s = stash;
1472		s->s = NULL;
1473		stash += sizeof(struct usb_string);
1474
1475	}
1476	gs_array[n_gs] = NULL;
1477	return uc;
1478}
1479
1480/**
1481 * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1482 * @cdev: the device whose string descriptor IDs are being allocated
1483 * and attached.
1484 * @sp: an array of usb_gadget_strings to attach.
1485 * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1486 *
1487 * This function will create a deep copy of usb_gadget_strings and usb_string
1488 * and attach it to the cdev. The actual string (usb_string.s) will not be
1489 * copied but only a referenced will be made. The struct usb_gadget_strings
1490 * array may contain multiple languages and should be NULL terminated.
1491 * The ->language pointer of each struct usb_gadget_strings has to contain the
1492 * same amount of entries.
1493 * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1494 * usb_string entry of es-ES contains the translation of the first usb_string
1495 * entry of en-US. Therefore both entries become the same id assign.
1496 */
1497struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1498		struct usb_gadget_strings **sp, unsigned n_strings)
1499{
1500	struct usb_gadget_string_container *uc;
1501	struct usb_gadget_strings **n_gs;
1502	unsigned n_gstrings = 0;
1503	unsigned i;
1504	int ret;
1505
1506	for (i = 0; sp[i]; i++)
1507		n_gstrings++;
1508
1509	if (!n_gstrings)
1510		return ERR_PTR(-EINVAL);
1511
1512	uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1513	if (IS_ERR(uc))
1514		return ERR_CAST(uc);
1515
1516	n_gs = get_containers_gs(uc);
1517	ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1518	if (ret)
1519		goto err;
1520
1521	for (i = 1; i < n_gstrings; i++) {
1522		struct usb_string *m_s;
1523		struct usb_string *s;
1524		unsigned n;
1525
1526		m_s = n_gs[0]->strings;
1527		s = n_gs[i]->strings;
1528		for (n = 0; n < n_strings; n++) {
1529			s->id = m_s->id;
1530			s++;
1531			m_s++;
1532		}
1533	}
1534	list_add_tail(&uc->list, &cdev->gstrings);
1535	return n_gs[0]->strings;
1536err:
1537	kfree(uc);
1538	return ERR_PTR(ret);
1539}
1540EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1541
1542/**
1543 * usb_string_ids_n() - allocate unused string IDs in batch
1544 * @c: the device whose string descriptor IDs are being allocated
1545 * @n: number of string IDs to allocate
1546 * Context: single threaded during gadget setup
1547 *
1548 * Returns the first requested ID.  This ID and next @n-1 IDs are now
1549 * valid IDs.  At least provided that @n is non-zero because if it
1550 * is, returns last requested ID which is now very useful information.
1551 *
1552 * @usb_string_ids_n() is called from bind() callbacks to allocate
1553 * string IDs.  Drivers for functions, configurations, or gadgets will
1554 * then store that ID in the appropriate descriptors and string table.
1555 *
1556 * All string identifier should be allocated using this,
1557 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1558 * example different functions don't wrongly assign different meanings
1559 * to the same identifier.
1560 */
1561int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1562{
1563	unsigned next = c->next_string_id;
1564	if (unlikely(n > 254 || (unsigned)next + n > 254))
1565		return -ENODEV;
1566	c->next_string_id += n;
1567	return next + 1;
1568}
1569EXPORT_SYMBOL_GPL(usb_string_ids_n);
1570
1571/*-------------------------------------------------------------------------*/
1572
1573static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1574{
1575	struct usb_composite_dev *cdev;
1576
1577	if (req->status || req->actual != req->length)
1578		DBG((struct usb_composite_dev *) ep->driver_data,
1579				"setup complete --> %d, %d/%d\n",
1580				req->status, req->actual, req->length);
1581
1582	/*
1583	 * REVIST The same ep0 requests are shared with function drivers
1584	 * so they don't have to maintain the same ->complete() stubs.
1585	 *
1586	 * Because of that, we need to check for the validity of ->context
1587	 * here, even though we know we've set it to something useful.
1588	 */
1589	if (!req->context)
1590		return;
1591
1592	cdev = req->context;
1593
1594	if (cdev->req == req)
1595		cdev->setup_pending = false;
1596	else if (cdev->os_desc_req == req)
1597		cdev->os_desc_pending = false;
1598	else
1599		WARN(1, "unknown request %p\n", req);
1600}
1601
1602static int composite_ep0_queue(struct usb_composite_dev *cdev,
1603		struct usb_request *req, gfp_t gfp_flags)
1604{
1605	int ret;
1606
1607	ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1608	if (ret == 0) {
1609		if (cdev->req == req)
1610			cdev->setup_pending = true;
1611		else if (cdev->os_desc_req == req)
1612			cdev->os_desc_pending = true;
1613		else
1614			WARN(1, "unknown request %p\n", req);
1615	}
1616
1617	return ret;
1618}
1619
1620static int count_ext_compat(struct usb_configuration *c)
1621{
1622	int i, res;
1623
1624	res = 0;
1625	for (i = 0; i < c->next_interface_id; ++i) {
1626		struct usb_function *f;
1627		int j;
1628
1629		f = c->interface[i];
1630		for (j = 0; j < f->os_desc_n; ++j) {
1631			struct usb_os_desc *d;
1632
1633			if (i != f->os_desc_table[j].if_id)
1634				continue;
1635			d = f->os_desc_table[j].os_desc;
1636			if (d && d->ext_compat_id)
1637				++res;
1638		}
1639	}
1640	BUG_ON(res > 255);
1641	return res;
1642}
1643
1644static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1645{
1646	int i, count;
1647
1648	count = 16;
1649	buf += 16;
1650	for (i = 0; i < c->next_interface_id; ++i) {
1651		struct usb_function *f;
1652		int j;
1653
1654		f = c->interface[i];
1655		for (j = 0; j < f->os_desc_n; ++j) {
1656			struct usb_os_desc *d;
1657
1658			if (i != f->os_desc_table[j].if_id)
1659				continue;
1660			d = f->os_desc_table[j].os_desc;
1661			if (d && d->ext_compat_id) {
1662				*buf++ = i;
1663				*buf++ = 0x01;
1664				memcpy(buf, d->ext_compat_id, 16);
1665				buf += 22;
1666			} else {
1667				++buf;
1668				*buf = 0x01;
1669				buf += 23;
1670			}
1671			count += 24;
1672			if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1673				return count;
1674		}
1675	}
1676
1677	return count;
1678}
1679
1680static int count_ext_prop(struct usb_configuration *c, int interface)
1681{
1682	struct usb_function *f;
1683	int j;
1684
1685	f = c->interface[interface];
1686	for (j = 0; j < f->os_desc_n; ++j) {
1687		struct usb_os_desc *d;
1688
1689		if (interface != f->os_desc_table[j].if_id)
1690			continue;
1691		d = f->os_desc_table[j].os_desc;
1692		if (d && d->ext_compat_id)
1693			return d->ext_prop_count;
1694	}
1695	return 0;
1696}
1697
1698static int len_ext_prop(struct usb_configuration *c, int interface)
1699{
1700	struct usb_function *f;
1701	struct usb_os_desc *d;
1702	int j, res;
1703
1704	res = 10; /* header length */
1705	f = c->interface[interface];
1706	for (j = 0; j < f->os_desc_n; ++j) {
1707		if (interface != f->os_desc_table[j].if_id)
1708			continue;
1709		d = f->os_desc_table[j].os_desc;
1710		if (d)
1711			return min(res + d->ext_prop_len, 4096);
1712	}
1713	return res;
1714}
1715
1716static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1717{
1718	struct usb_function *f;
1719	struct usb_os_desc *d;
1720	struct usb_os_desc_ext_prop *ext_prop;
1721	int j, count, n, ret;
1722
1723	f = c->interface[interface];
1724	count = 10; /* header length */
1725	buf += 10;
1726	for (j = 0; j < f->os_desc_n; ++j) {
1727		if (interface != f->os_desc_table[j].if_id)
1728			continue;
1729		d = f->os_desc_table[j].os_desc;
1730		if (d)
1731			list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1732				n = ext_prop->data_len +
1733					ext_prop->name_len + 14;
1734				if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1735					return count;
1736				usb_ext_prop_put_size(buf, n);
1737				usb_ext_prop_put_type(buf, ext_prop->type);
1738				ret = usb_ext_prop_put_name(buf, ext_prop->name,
1739							    ext_prop->name_len);
1740				if (ret < 0)
1741					return ret;
1742				switch (ext_prop->type) {
1743				case USB_EXT_PROP_UNICODE:
1744				case USB_EXT_PROP_UNICODE_ENV:
1745				case USB_EXT_PROP_UNICODE_LINK:
1746					usb_ext_prop_put_unicode(buf, ret,
1747							 ext_prop->data,
1748							 ext_prop->data_len);
1749					break;
1750				case USB_EXT_PROP_BINARY:
1751					usb_ext_prop_put_binary(buf, ret,
1752							ext_prop->data,
1753							ext_prop->data_len);
1754					break;
1755				case USB_EXT_PROP_LE32:
1756					/* not implemented */
1757				case USB_EXT_PROP_BE32:
1758					/* not implemented */
1759				default:
1760					return -EINVAL;
1761				}
1762				buf += n;
1763				count += n;
1764			}
1765	}
1766
1767	return count;
1768}
1769
1770/*
1771 * The setup() callback implements all the ep0 functionality that's
1772 * not handled lower down, in hardware or the hardware driver(like
1773 * device and endpoint feature flags, and their status).  It's all
1774 * housekeeping for the gadget function we're implementing.  Most of
1775 * the work is in config and function specific setup.
1776 */
1777int
1778composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1779{
1780	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
1781	struct usb_request		*req = cdev->req;
1782	int				value = -EOPNOTSUPP;
1783	int				status = 0;
1784	u16				w_index = le16_to_cpu(ctrl->wIndex);
1785	u8				intf = w_index & 0xFF;
1786	u16				w_value = le16_to_cpu(ctrl->wValue);
1787	u16				w_length = le16_to_cpu(ctrl->wLength);
1788	struct usb_function		*f = NULL;
1789	struct usb_function		*iter;
1790	u8				endp;
1791
1792	if (w_length > USB_COMP_EP0_BUFSIZ) {
1793		if (ctrl->bRequestType & USB_DIR_IN) {
1794			/* Cast away the const, we are going to overwrite on purpose. */
1795			__le16 *temp = (__le16 *)&ctrl->wLength;
1796
1797			*temp = cpu_to_le16(USB_COMP_EP0_BUFSIZ);
1798			w_length = USB_COMP_EP0_BUFSIZ;
1799		} else {
1800			goto done;
1801		}
1802	}
1803
1804	/* partial re-init of the response message; the function or the
1805	 * gadget might need to intercept e.g. a control-OUT completion
1806	 * when we delegate to it.
1807	 */
1808	req->zero = 0;
1809	req->context = cdev;
1810	req->complete = composite_setup_complete;
1811	req->length = 0;
1812	gadget->ep0->driver_data = cdev;
1813
1814	/*
1815	 * Don't let non-standard requests match any of the cases below
1816	 * by accident.
1817	 */
1818	if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1819		goto unknown;
1820
1821	switch (ctrl->bRequest) {
1822
1823	/* we handle all standard USB descriptors */
1824	case USB_REQ_GET_DESCRIPTOR:
1825		if (ctrl->bRequestType != USB_DIR_IN)
1826			goto unknown;
1827		switch (w_value >> 8) {
1828
1829		case USB_DT_DEVICE:
1830			cdev->desc.bNumConfigurations =
1831				count_configs(cdev, USB_DT_DEVICE);
1832			cdev->desc.bMaxPacketSize0 =
1833				cdev->gadget->ep0->maxpacket;
1834			if (gadget_is_superspeed(gadget)) {
1835				if (gadget->speed >= USB_SPEED_SUPER) {
1836					cdev->desc.bcdUSB = cpu_to_le16(0x0320);
1837					cdev->desc.bMaxPacketSize0 = 9;
1838				} else {
1839					cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1840				}
1841			} else {
1842				if (gadget->lpm_capable || cdev->use_webusb)
1843					cdev->desc.bcdUSB = cpu_to_le16(0x0201);
1844				else
1845					cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1846			}
1847
1848			value = min_t(u16, w_length, sizeof(cdev->desc));
1849			memcpy(req->buf, &cdev->desc, value);
1850			break;
1851		case USB_DT_DEVICE_QUALIFIER:
1852			if (!gadget_is_dualspeed(gadget) ||
1853			    gadget->speed >= USB_SPEED_SUPER)
1854				break;
1855			device_qual(cdev);
1856			value = min_t(int, w_length,
1857				sizeof(struct usb_qualifier_descriptor));
1858			break;
1859		case USB_DT_OTHER_SPEED_CONFIG:
1860			if (!gadget_is_dualspeed(gadget) ||
1861			    gadget->speed >= USB_SPEED_SUPER)
1862				break;
1863			fallthrough;
1864		case USB_DT_CONFIG:
1865			value = config_desc(cdev, w_value);
1866			if (value >= 0)
1867				value = min_t(u16, w_length, value);
1868			break;
1869		case USB_DT_STRING:
1870			value = get_string(cdev, req->buf,
1871					w_index, w_value & 0xff);
1872			if (value >= 0)
1873				value = min_t(u16, w_length, value);
1874			break;
1875		case USB_DT_BOS:
1876			if (gadget_is_superspeed(gadget) ||
1877			    gadget->lpm_capable || cdev->use_webusb) {
1878				value = bos_desc(cdev);
1879				value = min_t(u16, w_length, value);
1880			}
1881			break;
1882		case USB_DT_OTG:
1883			if (gadget_is_otg(gadget)) {
1884				struct usb_configuration *config;
1885				int otg_desc_len = 0;
1886
1887				if (cdev->config)
1888					config = cdev->config;
1889				else
1890					config = list_first_entry(
1891							&cdev->configs,
1892						struct usb_configuration, list);
1893				if (!config)
1894					goto done;
1895
1896				if (gadget->otg_caps &&
1897					(gadget->otg_caps->otg_rev >= 0x0200))
1898					otg_desc_len += sizeof(
1899						struct usb_otg20_descriptor);
1900				else
1901					otg_desc_len += sizeof(
1902						struct usb_otg_descriptor);
1903
1904				value = min_t(int, w_length, otg_desc_len);
1905				memcpy(req->buf, config->descriptors[0], value);
1906			}
1907			break;
1908		}
1909		break;
1910
1911	/* any number of configs can work */
1912	case USB_REQ_SET_CONFIGURATION:
1913		if (ctrl->bRequestType != 0)
1914			goto unknown;
1915		if (gadget_is_otg(gadget)) {
1916			if (gadget->a_hnp_support)
1917				DBG(cdev, "HNP available\n");
1918			else if (gadget->a_alt_hnp_support)
1919				DBG(cdev, "HNP on another port\n");
1920			else
1921				VDBG(cdev, "HNP inactive\n");
1922		}
1923		spin_lock(&cdev->lock);
1924		value = set_config(cdev, ctrl, w_value);
1925		spin_unlock(&cdev->lock);
1926		break;
1927	case USB_REQ_GET_CONFIGURATION:
1928		if (ctrl->bRequestType != USB_DIR_IN)
1929			goto unknown;
1930		if (cdev->config)
1931			*(u8 *)req->buf = cdev->config->bConfigurationValue;
1932		else
1933			*(u8 *)req->buf = 0;
1934		value = min_t(u16, w_length, 1);
1935		break;
1936
1937	/* function drivers must handle get/set altsetting */
1938	case USB_REQ_SET_INTERFACE:
1939		if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1940			goto unknown;
1941		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1942			break;
1943		f = cdev->config->interface[intf];
1944		if (!f)
1945			break;
1946
1947		/*
1948		 * If there's no get_alt() method, we know only altsetting zero
1949		 * works. There is no need to check if set_alt() is not NULL
1950		 * as we check this in usb_add_function().
1951		 */
1952		if (w_value && !f->get_alt)
1953			break;
1954
1955		spin_lock(&cdev->lock);
1956		value = f->set_alt(f, w_index, w_value);
1957		if (value == USB_GADGET_DELAYED_STATUS) {
1958			DBG(cdev,
1959			 "%s: interface %d (%s) requested delayed status\n",
1960					__func__, intf, f->name);
1961			cdev->delayed_status++;
1962			DBG(cdev, "delayed_status count %d\n",
1963					cdev->delayed_status);
1964		}
1965		spin_unlock(&cdev->lock);
1966		break;
1967	case USB_REQ_GET_INTERFACE:
1968		if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1969			goto unknown;
1970		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1971			break;
1972		f = cdev->config->interface[intf];
1973		if (!f)
1974			break;
1975		/* lots of interfaces only need altsetting zero... */
1976		value = f->get_alt ? f->get_alt(f, w_index) : 0;
1977		if (value < 0)
1978			break;
1979		*((u8 *)req->buf) = value;
1980		value = min_t(u16, w_length, 1);
1981		break;
1982	case USB_REQ_GET_STATUS:
1983		if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1984						(w_index == OTG_STS_SELECTOR)) {
1985			if (ctrl->bRequestType != (USB_DIR_IN |
1986							USB_RECIP_DEVICE))
1987				goto unknown;
1988			*((u8 *)req->buf) = gadget->host_request_flag;
1989			value = 1;
1990			break;
1991		}
1992
1993		/*
1994		 * USB 3.0 additions:
1995		 * Function driver should handle get_status request. If such cb
1996		 * wasn't supplied we respond with default value = 0
1997		 * Note: function driver should supply such cb only for the
1998		 * first interface of the function
1999		 */
2000		if (!gadget_is_superspeed(gadget))
2001			goto unknown;
2002		if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
2003			goto unknown;
2004		value = 2;	/* This is the length of the get_status reply */
2005		put_unaligned_le16(0, req->buf);
2006		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
2007			break;
2008		f = cdev->config->interface[intf];
2009		if (!f)
2010			break;
2011
2012		if (f->get_status) {
2013			status = f->get_status(f);
2014			if (status < 0)
2015				break;
2016		} else {
2017			/* Set D0 and D1 bits based on func wakeup capability */
2018			if (f->config->bmAttributes & USB_CONFIG_ATT_WAKEUP) {
2019				status |= USB_INTRF_STAT_FUNC_RW_CAP;
2020				if (f->func_wakeup_armed)
2021					status |= USB_INTRF_STAT_FUNC_RW;
2022			}
2023		}
2024
2025		put_unaligned_le16(status & 0x0000ffff, req->buf);
2026		break;
2027	/*
2028	 * Function drivers should handle SetFeature/ClearFeature
2029	 * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
2030	 * only for the first interface of the function
2031	 */
2032	case USB_REQ_CLEAR_FEATURE:
2033	case USB_REQ_SET_FEATURE:
2034		if (!gadget_is_superspeed(gadget))
2035			goto unknown;
2036		if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
2037			goto unknown;
2038		switch (w_value) {
2039		case USB_INTRF_FUNC_SUSPEND:
2040			if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
2041				break;
2042			f = cdev->config->interface[intf];
2043			if (!f)
2044				break;
2045			value = 0;
2046			if (f->func_suspend) {
2047				value = f->func_suspend(f, w_index >> 8);
2048			/* SetFeature(FUNCTION_SUSPEND) */
2049			} else if (ctrl->bRequest == USB_REQ_SET_FEATURE) {
2050				if (!(f->config->bmAttributes &
2051				      USB_CONFIG_ATT_WAKEUP) &&
2052				     (w_index & USB_INTRF_FUNC_SUSPEND_RW))
2053					break;
2054
2055				f->func_wakeup_armed = !!(w_index &
2056							  USB_INTRF_FUNC_SUSPEND_RW);
2057
2058				if (w_index & USB_INTRF_FUNC_SUSPEND_LP) {
2059					if (f->suspend && !f->func_suspended) {
2060						f->suspend(f);
2061						f->func_suspended = true;
2062					}
2063				/*
2064				 * Handle cases where host sends function resume
2065				 * through SetFeature(FUNCTION_SUSPEND) but low power
2066				 * bit reset
2067				 */
2068				} else {
2069					if (f->resume && f->func_suspended) {
2070						f->resume(f);
2071						f->func_suspended = false;
2072					}
2073				}
2074			/* ClearFeature(FUNCTION_SUSPEND) */
2075			} else if (ctrl->bRequest == USB_REQ_CLEAR_FEATURE) {
2076				f->func_wakeup_armed = false;
2077
2078				if (f->resume && f->func_suspended) {
2079					f->resume(f);
2080					f->func_suspended = false;
2081				}
2082			}
2083
2084			if (value < 0) {
2085				ERROR(cdev,
2086				      "func_suspend() returned error %d\n",
2087				      value);
2088				value = 0;
2089			}
2090			break;
2091		}
2092		break;
2093	default:
2094unknown:
2095		/*
2096		 * OS descriptors handling
2097		 */
2098		if (cdev->use_os_string && cdev->os_desc_config &&
2099		    (ctrl->bRequestType & USB_TYPE_VENDOR) &&
2100		    ctrl->bRequest == cdev->b_vendor_code) {
2101			struct usb_configuration	*os_desc_cfg;
2102			u8				*buf;
2103			int				interface;
2104			int				count = 0;
2105
2106			req = cdev->os_desc_req;
2107			req->context = cdev;
2108			req->complete = composite_setup_complete;
2109			buf = req->buf;
2110			os_desc_cfg = cdev->os_desc_config;
2111			w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
2112			memset(buf, 0, w_length);
2113			buf[5] = 0x01;
2114			switch (ctrl->bRequestType & USB_RECIP_MASK) {
2115			/*
2116			 * The Microsoft CompatID OS Descriptor Spec(w_index = 0x4) and
2117			 * Extended Prop OS Desc Spec(w_index = 0x5) state that the
2118			 * HighByte of wValue is the InterfaceNumber and the LowByte is
2119			 * the PageNumber. This high/low byte ordering is incorrectly
2120			 * documented in the Spec. USB analyzer output on the below
2121			 * request packets show the high/low byte inverted i.e LowByte
2122			 * is the InterfaceNumber and the HighByte is the PageNumber.
2123			 * Since we dont support >64KB CompatID/ExtendedProp descriptors,
2124			 * PageNumber is set to 0. Hence verify that the HighByte is 0
2125			 * for below two cases.
2126			 */
2127			case USB_RECIP_DEVICE:
2128				if (w_index != 0x4 || (w_value >> 8))
2129					break;
2130				buf[6] = w_index;
2131				/* Number of ext compat interfaces */
2132				count = count_ext_compat(os_desc_cfg);
2133				buf[8] = count;
2134				count *= 24; /* 24 B/ext compat desc */
2135				count += 16; /* header */
2136				put_unaligned_le32(count, buf);
2137				value = w_length;
2138				if (w_length > 0x10) {
2139					value = fill_ext_compat(os_desc_cfg, buf);
2140					value = min_t(u16, w_length, value);
2141				}
2142				break;
2143			case USB_RECIP_INTERFACE:
2144				if (w_index != 0x5 || (w_value >> 8))
2145					break;
2146				interface = w_value & 0xFF;
2147				if (interface >= MAX_CONFIG_INTERFACES ||
2148				    !os_desc_cfg->interface[interface])
2149					break;
2150				buf[6] = w_index;
2151				count = count_ext_prop(os_desc_cfg,
2152					interface);
2153				put_unaligned_le16(count, buf + 8);
2154				count = len_ext_prop(os_desc_cfg,
2155					interface);
2156				put_unaligned_le32(count, buf);
2157				value = w_length;
2158				if (w_length > 0x0A) {
2159					value = fill_ext_prop(os_desc_cfg,
2160							      interface, buf);
2161					if (value >= 0)
2162						value = min_t(u16, w_length, value);
2163				}
2164				break;
2165			}
2166
2167			goto check_value;
2168		}
2169
2170		/*
2171		 * WebUSB URL descriptor handling, following:
2172		 * https://wicg.github.io/webusb/#device-requests
2173		 */
2174		if (cdev->use_webusb &&
2175		    ctrl->bRequestType == (USB_DIR_IN | USB_TYPE_VENDOR) &&
2176		    w_index == WEBUSB_GET_URL &&
2177		    w_value == WEBUSB_LANDING_PAGE_PRESENT &&
2178		    ctrl->bRequest == cdev->b_webusb_vendor_code) {
2179			unsigned int	landing_page_length;
2180			unsigned int	landing_page_offset;
2181			struct webusb_url_descriptor *url_descriptor =
2182					(struct webusb_url_descriptor *)cdev->req->buf;
2183
2184			url_descriptor->bDescriptorType = WEBUSB_URL_DESCRIPTOR_TYPE;
2185
2186			if (strncasecmp(cdev->landing_page, "https://",  8) == 0) {
2187				landing_page_offset = 8;
2188				url_descriptor->bScheme = WEBUSB_URL_SCHEME_HTTPS;
2189			} else if (strncasecmp(cdev->landing_page, "http://", 7) == 0) {
2190				landing_page_offset = 7;
2191				url_descriptor->bScheme = WEBUSB_URL_SCHEME_HTTP;
2192			} else {
2193				landing_page_offset = 0;
2194				url_descriptor->bScheme = WEBUSB_URL_SCHEME_NONE;
2195			}
2196
2197			landing_page_length = strnlen(cdev->landing_page,
2198				sizeof(url_descriptor->URL)
2199				- WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + landing_page_offset);
2200
2201			if (w_length < WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + landing_page_length)
2202				landing_page_length = w_length
2203				- WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + landing_page_offset;
2204
2205			memcpy(url_descriptor->URL,
2206				cdev->landing_page + landing_page_offset,
2207				landing_page_length - landing_page_offset);
2208			url_descriptor->bLength = landing_page_length
2209				- landing_page_offset + WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH;
2210
2211			value = url_descriptor->bLength;
2212
2213			goto check_value;
2214		}
2215
2216		VDBG(cdev,
2217			"non-core control req%02x.%02x v%04x i%04x l%d\n",
2218			ctrl->bRequestType, ctrl->bRequest,
2219			w_value, w_index, w_length);
2220
2221		/* functions always handle their interfaces and endpoints...
2222		 * punt other recipients (other, WUSB, ...) to the current
2223		 * configuration code.
2224		 */
2225		if (cdev->config) {
2226			list_for_each_entry(f, &cdev->config->functions, list)
2227				if (f->req_match &&
2228				    f->req_match(f, ctrl, false))
2229					goto try_fun_setup;
2230		} else {
2231			struct usb_configuration *c;
2232			list_for_each_entry(c, &cdev->configs, list)
2233				list_for_each_entry(f, &c->functions, list)
2234					if (f->req_match &&
2235					    f->req_match(f, ctrl, true))
2236						goto try_fun_setup;
2237		}
2238		f = NULL;
2239
2240		switch (ctrl->bRequestType & USB_RECIP_MASK) {
2241		case USB_RECIP_INTERFACE:
2242			if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
2243				break;
2244			f = cdev->config->interface[intf];
2245			break;
2246
2247		case USB_RECIP_ENDPOINT:
2248			if (!cdev->config)
2249				break;
2250			endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
2251			list_for_each_entry(iter, &cdev->config->functions, list) {
2252				if (test_bit(endp, iter->endpoints)) {
2253					f = iter;
2254					break;
2255				}
2256			}
 
 
2257			break;
2258		}
2259try_fun_setup:
2260		if (f && f->setup)
2261			value = f->setup(f, ctrl);
2262		else {
2263			struct usb_configuration	*c;
2264
2265			c = cdev->config;
2266			if (!c)
2267				goto done;
2268
2269			/* try current config's setup */
2270			if (c->setup) {
2271				value = c->setup(c, ctrl);
2272				goto done;
2273			}
2274
2275			/* try the only function in the current config */
2276			if (!list_is_singular(&c->functions))
2277				goto done;
2278			f = list_first_entry(&c->functions, struct usb_function,
2279					     list);
2280			if (f->setup)
2281				value = f->setup(f, ctrl);
2282		}
2283
2284		goto done;
2285	}
2286
2287check_value:
2288	/* respond with data transfer before status phase? */
2289	if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
2290		req->length = value;
2291		req->context = cdev;
2292		req->zero = value < w_length;
2293		value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2294		if (value < 0) {
2295			DBG(cdev, "ep_queue --> %d\n", value);
2296			req->status = 0;
2297			composite_setup_complete(gadget->ep0, req);
2298		}
2299	} else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
2300		WARN(cdev,
2301			"%s: Delayed status not supported for w_length != 0",
2302			__func__);
2303	}
2304
2305done:
2306	/* device either stalls (value < 0) or reports success */
2307	return value;
2308}
2309
2310static void __composite_disconnect(struct usb_gadget *gadget)
2311{
2312	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2313	unsigned long			flags;
2314
2315	/* REVISIT:  should we have config and device level
2316	 * disconnect callbacks?
2317	 */
2318	spin_lock_irqsave(&cdev->lock, flags);
2319	cdev->suspended = 0;
2320	if (cdev->config)
2321		reset_config(cdev);
2322	if (cdev->driver->disconnect)
2323		cdev->driver->disconnect(cdev);
2324	spin_unlock_irqrestore(&cdev->lock, flags);
2325}
2326
2327void composite_disconnect(struct usb_gadget *gadget)
2328{
2329	usb_gadget_vbus_draw(gadget, 0);
2330	__composite_disconnect(gadget);
2331}
2332
2333void composite_reset(struct usb_gadget *gadget)
2334{
2335	/*
2336	 * Section 1.4.13 Standard Downstream Port of the USB battery charging
2337	 * specification v1.2 states that a device connected on a SDP shall only
2338	 * draw at max 100mA while in a connected, but unconfigured state.
2339	 */
2340	usb_gadget_vbus_draw(gadget, 100);
2341	__composite_disconnect(gadget);
2342}
2343
2344/*-------------------------------------------------------------------------*/
2345
2346static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2347			      char *buf)
2348{
2349	struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2350	struct usb_composite_dev *cdev = get_gadget_data(gadget);
2351
2352	return sprintf(buf, "%d\n", cdev->suspended);
2353}
2354static DEVICE_ATTR_RO(suspended);
2355
2356static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2357{
2358	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2359	struct usb_gadget_strings	*gstr = cdev->driver->strings[0];
2360	struct usb_string		*dev_str = gstr->strings;
2361
2362	/* composite_disconnect() must already have been called
2363	 * by the underlying peripheral controller driver!
2364	 * so there's no i/o concurrency that could affect the
2365	 * state protected by cdev->lock.
2366	 */
2367	WARN_ON(cdev->config);
2368
2369	while (!list_empty(&cdev->configs)) {
2370		struct usb_configuration	*c;
2371		c = list_first_entry(&cdev->configs,
2372				struct usb_configuration, list);
2373		remove_config(cdev, c);
2374	}
2375	if (cdev->driver->unbind && unbind_driver)
2376		cdev->driver->unbind(cdev);
2377
2378	composite_dev_cleanup(cdev);
2379
2380	if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
2381		dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
2382
2383	kfree(cdev->def_manufacturer);
2384	kfree(cdev);
2385	set_gadget_data(gadget, NULL);
2386}
2387
2388static void composite_unbind(struct usb_gadget *gadget)
2389{
2390	__composite_unbind(gadget, true);
2391}
2392
2393static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2394		const struct usb_device_descriptor *old)
2395{
2396	__le16 idVendor;
2397	__le16 idProduct;
2398	__le16 bcdDevice;
2399	u8 iSerialNumber;
2400	u8 iManufacturer;
2401	u8 iProduct;
2402
2403	/*
2404	 * these variables may have been set in
2405	 * usb_composite_overwrite_options()
2406	 */
2407	idVendor = new->idVendor;
2408	idProduct = new->idProduct;
2409	bcdDevice = new->bcdDevice;
2410	iSerialNumber = new->iSerialNumber;
2411	iManufacturer = new->iManufacturer;
2412	iProduct = new->iProduct;
2413
2414	*new = *old;
2415	if (idVendor)
2416		new->idVendor = idVendor;
2417	if (idProduct)
2418		new->idProduct = idProduct;
2419	if (bcdDevice)
2420		new->bcdDevice = bcdDevice;
2421	else
2422		new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2423	if (iSerialNumber)
2424		new->iSerialNumber = iSerialNumber;
2425	if (iManufacturer)
2426		new->iManufacturer = iManufacturer;
2427	if (iProduct)
2428		new->iProduct = iProduct;
2429}
2430
2431int composite_dev_prepare(struct usb_composite_driver *composite,
2432		struct usb_composite_dev *cdev)
2433{
2434	struct usb_gadget *gadget = cdev->gadget;
2435	int ret = -ENOMEM;
2436
2437	/* preallocate control response and buffer */
2438	cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2439	if (!cdev->req)
2440		return -ENOMEM;
2441
2442	cdev->req->buf = kzalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2443	if (!cdev->req->buf)
2444		goto fail;
2445
2446	ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2447	if (ret)
2448		goto fail_dev;
2449
2450	cdev->req->complete = composite_setup_complete;
2451	cdev->req->context = cdev;
2452	gadget->ep0->driver_data = cdev;
2453
2454	cdev->driver = composite;
2455
2456	/*
2457	 * As per USB compliance update, a device that is actively drawing
2458	 * more than 100mA from USB must report itself as bus-powered in
2459	 * the GetStatus(DEVICE) call.
2460	 */
2461	if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2462		usb_gadget_set_selfpowered(gadget);
2463
2464	/* interface and string IDs start at zero via kzalloc.
2465	 * we force endpoints to start unassigned; few controller
2466	 * drivers will zero ep->driver_data.
2467	 */
2468	usb_ep_autoconfig_reset(gadget);
2469	return 0;
2470fail_dev:
2471	kfree(cdev->req->buf);
2472fail:
2473	usb_ep_free_request(gadget->ep0, cdev->req);
2474	cdev->req = NULL;
2475	return ret;
2476}
2477
2478int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2479				  struct usb_ep *ep0)
2480{
2481	int ret = 0;
2482
2483	cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2484	if (!cdev->os_desc_req) {
2485		ret = -ENOMEM;
2486		goto end;
2487	}
2488
2489	cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2490					 GFP_KERNEL);
2491	if (!cdev->os_desc_req->buf) {
2492		ret = -ENOMEM;
2493		usb_ep_free_request(ep0, cdev->os_desc_req);
2494		goto end;
2495	}
2496	cdev->os_desc_req->context = cdev;
2497	cdev->os_desc_req->complete = composite_setup_complete;
2498end:
2499	return ret;
2500}
2501
2502void composite_dev_cleanup(struct usb_composite_dev *cdev)
2503{
2504	struct usb_gadget_string_container *uc, *tmp;
2505	struct usb_ep			   *ep, *tmp_ep;
2506
2507	list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2508		list_del(&uc->list);
2509		kfree(uc);
2510	}
2511	if (cdev->os_desc_req) {
2512		if (cdev->os_desc_pending)
2513			usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2514
2515		kfree(cdev->os_desc_req->buf);
2516		cdev->os_desc_req->buf = NULL;
2517		usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2518		cdev->os_desc_req = NULL;
2519	}
2520	if (cdev->req) {
2521		if (cdev->setup_pending)
2522			usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2523
2524		kfree(cdev->req->buf);
2525		cdev->req->buf = NULL;
2526		usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2527		cdev->req = NULL;
2528	}
2529	cdev->next_string_id = 0;
2530	device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2531
2532	/*
2533	 * Some UDC backends have a dynamic EP allocation scheme.
2534	 *
2535	 * In that case, the dispose() callback is used to notify the
2536	 * backend that the EPs are no longer in use.
2537	 *
2538	 * Note: The UDC backend can remove the EP from the ep_list as
2539	 *	 a result, so we need to use the _safe list iterator.
2540	 */
2541	list_for_each_entry_safe(ep, tmp_ep,
2542				 &cdev->gadget->ep_list, ep_list) {
2543		if (ep->ops->dispose)
2544			ep->ops->dispose(ep);
2545	}
2546}
2547
2548static int composite_bind(struct usb_gadget *gadget,
2549		struct usb_gadget_driver *gdriver)
2550{
2551	struct usb_composite_dev	*cdev;
2552	struct usb_composite_driver	*composite = to_cdriver(gdriver);
2553	int				status = -ENOMEM;
2554
2555	cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2556	if (!cdev)
2557		return status;
2558
2559	spin_lock_init(&cdev->lock);
2560	cdev->gadget = gadget;
2561	set_gadget_data(gadget, cdev);
2562	INIT_LIST_HEAD(&cdev->configs);
2563	INIT_LIST_HEAD(&cdev->gstrings);
2564
2565	status = composite_dev_prepare(composite, cdev);
2566	if (status)
2567		goto fail;
2568
2569	/* composite gadget needs to assign strings for whole device (like
2570	 * serial number), register function drivers, potentially update
2571	 * power state and consumption, etc
2572	 */
2573	status = composite->bind(cdev);
2574	if (status < 0)
2575		goto fail;
2576
2577	if (cdev->use_os_string) {
2578		status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2579		if (status)
2580			goto fail;
2581	}
2582
2583	update_unchanged_dev_desc(&cdev->desc, composite->dev);
2584
2585	/* has userspace failed to provide a serial number? */
2586	if (composite->needs_serial && !cdev->desc.iSerialNumber)
2587		WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2588
2589	INFO(cdev, "%s ready\n", composite->name);
2590	return 0;
2591
2592fail:
2593	__composite_unbind(gadget, false);
2594	return status;
2595}
2596
2597/*-------------------------------------------------------------------------*/
2598
2599void composite_suspend(struct usb_gadget *gadget)
2600{
2601	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2602	struct usb_function		*f;
2603
2604	/* REVISIT:  should we have config level
2605	 * suspend/resume callbacks?
2606	 */
2607	DBG(cdev, "suspend\n");
2608	if (cdev->config) {
2609		list_for_each_entry(f, &cdev->config->functions, list) {
2610			if (f->suspend)
2611				f->suspend(f);
2612		}
2613	}
2614	if (cdev->driver->suspend)
2615		cdev->driver->suspend(cdev);
2616
2617	cdev->suspended = 1;
2618
2619	if (cdev->config &&
2620	    cdev->config->bmAttributes & USB_CONFIG_ATT_SELFPOWER)
2621		usb_gadget_set_selfpowered(gadget);
2622
2623	usb_gadget_vbus_draw(gadget, 2);
2624}
2625
2626void composite_resume(struct usb_gadget *gadget)
2627{
2628	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2629	struct usb_function		*f;
2630	unsigned			maxpower;
2631
2632	/* REVISIT:  should we have config level
2633	 * suspend/resume callbacks?
2634	 */
2635	DBG(cdev, "resume\n");
2636	if (cdev->driver->resume)
2637		cdev->driver->resume(cdev);
2638	if (cdev->config) {
2639		list_for_each_entry(f, &cdev->config->functions, list) {
2640			/*
2641			 * Check for func_suspended flag to see if the function is
2642			 * in USB3 FUNCTION_SUSPEND state. In this case resume is
2643			 * done via FUNCTION_SUSPEND feature selector.
2644			 */
2645			if (f->resume && !f->func_suspended)
2646				f->resume(f);
2647		}
2648
2649		maxpower = cdev->config->MaxPower ?
2650			cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
2651		if (gadget->speed < USB_SPEED_SUPER)
2652			maxpower = min(maxpower, 500U);
2653		else
2654			maxpower = min(maxpower, 900U);
2655
2656		if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW ||
2657		    !(cdev->config->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
2658			usb_gadget_clear_selfpowered(gadget);
2659		else
2660			usb_gadget_set_selfpowered(gadget);
2661
2662		usb_gadget_vbus_draw(gadget, maxpower);
2663	} else {
2664		maxpower = CONFIG_USB_GADGET_VBUS_DRAW;
2665		maxpower = min(maxpower, 100U);
2666		usb_gadget_vbus_draw(gadget, maxpower);
2667	}
2668
2669	cdev->suspended = 0;
2670}
2671
2672/*-------------------------------------------------------------------------*/
2673
2674static const struct usb_gadget_driver composite_driver_template = {
2675	.bind		= composite_bind,
2676	.unbind		= composite_unbind,
2677
2678	.setup		= composite_setup,
2679	.reset		= composite_reset,
2680	.disconnect	= composite_disconnect,
2681
2682	.suspend	= composite_suspend,
2683	.resume		= composite_resume,
2684
2685	.driver	= {
2686		.owner		= THIS_MODULE,
2687	},
2688};
2689
2690/**
2691 * usb_composite_probe() - register a composite driver
2692 * @driver: the driver to register
2693 *
2694 * Context: single threaded during gadget setup
2695 *
2696 * This function is used to register drivers using the composite driver
2697 * framework.  The return value is zero, or a negative errno value.
2698 * Those values normally come from the driver's @bind method, which does
2699 * all the work of setting up the driver to match the hardware.
2700 *
2701 * On successful return, the gadget is ready to respond to requests from
2702 * the host, unless one of its components invokes usb_gadget_disconnect()
2703 * while it was binding.  That would usually be done in order to wait for
2704 * some userspace participation.
2705 */
2706int usb_composite_probe(struct usb_composite_driver *driver)
2707{
2708	struct usb_gadget_driver *gadget_driver;
2709
2710	if (!driver || !driver->dev || !driver->bind)
2711		return -EINVAL;
2712
2713	if (!driver->name)
2714		driver->name = "composite";
2715
2716	driver->gadget_driver = composite_driver_template;
2717	gadget_driver = &driver->gadget_driver;
2718
2719	gadget_driver->function =  (char *) driver->name;
2720	gadget_driver->driver.name = driver->name;
2721	gadget_driver->max_speed = driver->max_speed;
2722
2723	return usb_gadget_register_driver(gadget_driver);
2724}
2725EXPORT_SYMBOL_GPL(usb_composite_probe);
2726
2727/**
2728 * usb_composite_unregister() - unregister a composite driver
2729 * @driver: the driver to unregister
2730 *
2731 * This function is used to unregister drivers using the composite
2732 * driver framework.
2733 */
2734void usb_composite_unregister(struct usb_composite_driver *driver)
2735{
2736	usb_gadget_unregister_driver(&driver->gadget_driver);
2737}
2738EXPORT_SYMBOL_GPL(usb_composite_unregister);
2739
2740/**
2741 * usb_composite_setup_continue() - Continue with the control transfer
2742 * @cdev: the composite device who's control transfer was kept waiting
2743 *
2744 * This function must be called by the USB function driver to continue
2745 * with the control transfer's data/status stage in case it had requested to
2746 * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2747 * can request the composite framework to delay the setup request's data/status
2748 * stages by returning USB_GADGET_DELAYED_STATUS.
2749 */
2750void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2751{
2752	int			value;
2753	struct usb_request	*req = cdev->req;
2754	unsigned long		flags;
2755
2756	DBG(cdev, "%s\n", __func__);
2757	spin_lock_irqsave(&cdev->lock, flags);
2758
2759	if (cdev->delayed_status == 0) {
2760		WARN(cdev, "%s: Unexpected call\n", __func__);
2761
2762	} else if (--cdev->delayed_status == 0) {
2763		DBG(cdev, "%s: Completing delayed status\n", __func__);
2764		req->length = 0;
2765		req->context = cdev;
2766		value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2767		if (value < 0) {
2768			DBG(cdev, "ep_queue --> %d\n", value);
2769			req->status = 0;
2770			composite_setup_complete(cdev->gadget->ep0, req);
2771		}
2772	}
2773
2774	spin_unlock_irqrestore(&cdev->lock, flags);
2775}
2776EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2777
2778static char *composite_default_mfr(struct usb_gadget *gadget)
2779{
2780	return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2781			 init_utsname()->release, gadget->name);
2782}
2783
2784void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2785		struct usb_composite_overwrite *covr)
2786{
2787	struct usb_device_descriptor	*desc = &cdev->desc;
2788	struct usb_gadget_strings	*gstr = cdev->driver->strings[0];
2789	struct usb_string		*dev_str = gstr->strings;
2790
2791	if (covr->idVendor)
2792		desc->idVendor = cpu_to_le16(covr->idVendor);
2793
2794	if (covr->idProduct)
2795		desc->idProduct = cpu_to_le16(covr->idProduct);
2796
2797	if (covr->bcdDevice)
2798		desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2799
2800	if (covr->serial_number) {
2801		desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2802		dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2803	}
2804	if (covr->manufacturer) {
2805		desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2806		dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2807
2808	} else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2809		desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2810		cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2811		dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2812	}
2813
2814	if (covr->product) {
2815		desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2816		dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2817	}
2818}
2819EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2820
2821MODULE_DESCRIPTION("infrastructure for Composite USB Gadgets");
2822MODULE_LICENSE("GPL");
2823MODULE_AUTHOR("David Brownell");
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * composite.c - infrastructure for Composite USB Gadgets
   4 *
   5 * Copyright (C) 2006-2008 David Brownell
   6 */
   7
   8/* #define VERBOSE_DEBUG */
   9
  10#include <linux/kallsyms.h>
  11#include <linux/kernel.h>
  12#include <linux/slab.h>
  13#include <linux/module.h>
  14#include <linux/device.h>
  15#include <linux/utsname.h>
  16#include <linux/bitfield.h>
 
  17
  18#include <linux/usb/composite.h>
  19#include <linux/usb/otg.h>
  20#include <asm/unaligned.h>
 
  21
  22#include "u_os_desc.h"
  23
  24/**
  25 * struct usb_os_string - represents OS String to be reported by a gadget
  26 * @bLength: total length of the entire descritor, always 0x12
  27 * @bDescriptorType: USB_DT_STRING
  28 * @qwSignature: the OS String proper
  29 * @bMS_VendorCode: code used by the host for subsequent requests
  30 * @bPad: not used, must be zero
  31 */
  32struct usb_os_string {
  33	__u8	bLength;
  34	__u8	bDescriptorType;
  35	__u8	qwSignature[OS_STRING_QW_SIGN_LEN];
  36	__u8	bMS_VendorCode;
  37	__u8	bPad;
  38} __packed;
  39
  40/*
  41 * The code in this file is utility code, used to build a gadget driver
  42 * from one or more "function" drivers, one or more "configuration"
  43 * objects, and a "usb_composite_driver" by gluing them together along
  44 * with the relevant device-wide data.
  45 */
  46
  47static struct usb_gadget_strings **get_containers_gs(
  48		struct usb_gadget_string_container *uc)
  49{
  50	return (struct usb_gadget_strings **)uc->stash;
  51}
  52
  53/**
  54 * function_descriptors() - get function descriptors for speed
  55 * @f: the function
  56 * @speed: the speed
  57 *
  58 * Returns the descriptors or NULL if not set.
  59 */
  60static struct usb_descriptor_header **
  61function_descriptors(struct usb_function *f,
  62		     enum usb_device_speed speed)
  63{
  64	struct usb_descriptor_header **descriptors;
  65
  66	/*
  67	 * NOTE: we try to help gadget drivers which might not be setting
  68	 * max_speed appropriately.
  69	 */
  70
  71	switch (speed) {
  72	case USB_SPEED_SUPER_PLUS:
  73		descriptors = f->ssp_descriptors;
  74		if (descriptors)
  75			break;
  76		fallthrough;
  77	case USB_SPEED_SUPER:
  78		descriptors = f->ss_descriptors;
  79		if (descriptors)
  80			break;
  81		fallthrough;
  82	case USB_SPEED_HIGH:
  83		descriptors = f->hs_descriptors;
  84		if (descriptors)
  85			break;
  86		fallthrough;
  87	default:
  88		descriptors = f->fs_descriptors;
  89	}
  90
  91	/*
  92	 * if we can't find any descriptors at all, then this gadget deserves to
  93	 * Oops with a NULL pointer dereference
  94	 */
  95
  96	return descriptors;
  97}
  98
  99/**
 100 * next_desc() - advance to the next desc_type descriptor
 101 * @t: currect pointer within descriptor array
 102 * @desc_type: descriptor type
 103 *
 104 * Return: next desc_type descriptor or NULL
 105 *
 106 * Iterate over @t until either desc_type descriptor found or
 107 * NULL (that indicates end of list) encountered
 108 */
 109static struct usb_descriptor_header**
 110next_desc(struct usb_descriptor_header **t, u8 desc_type)
 111{
 112	for (; *t; t++) {
 113		if ((*t)->bDescriptorType == desc_type)
 114			return t;
 115	}
 116	return NULL;
 117}
 118
 119/*
 120 * for_each_desc() - iterate over desc_type descriptors in the
 121 * descriptors list
 122 * @start: pointer within descriptor array.
 123 * @iter_desc: desc_type descriptor to use as the loop cursor
 124 * @desc_type: wanted descriptr type
 125 */
 126#define for_each_desc(start, iter_desc, desc_type) \
 127	for (iter_desc = next_desc(start, desc_type); \
 128	     iter_desc; iter_desc = next_desc(iter_desc + 1, desc_type))
 129
 130/**
 131 * config_ep_by_speed_and_alt() - configures the given endpoint
 132 * according to gadget speed.
 133 * @g: pointer to the gadget
 134 * @f: usb function
 135 * @_ep: the endpoint to configure
 136 * @alt: alternate setting number
 137 *
 138 * Return: error code, 0 on success
 139 *
 140 * This function chooses the right descriptors for a given
 141 * endpoint according to gadget speed and saves it in the
 142 * endpoint desc field. If the endpoint already has a descriptor
 143 * assigned to it - overwrites it with currently corresponding
 144 * descriptor. The endpoint maxpacket field is updated according
 145 * to the chosen descriptor.
 146 * Note: the supplied function should hold all the descriptors
 147 * for supported speeds
 148 */
 149int config_ep_by_speed_and_alt(struct usb_gadget *g,
 150				struct usb_function *f,
 151				struct usb_ep *_ep,
 152				u8 alt)
 153{
 154	struct usb_endpoint_descriptor *chosen_desc = NULL;
 155	struct usb_interface_descriptor *int_desc = NULL;
 156	struct usb_descriptor_header **speed_desc = NULL;
 157
 158	struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
 159	int want_comp_desc = 0;
 160
 161	struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 
 
 162
 163	if (!g || !f || !_ep)
 164		return -EIO;
 165
 166	/* select desired speed */
 167	switch (g->speed) {
 168	case USB_SPEED_SUPER_PLUS:
 169		if (gadget_is_superspeed_plus(g)) {
 170			speed_desc = f->ssp_descriptors;
 171			want_comp_desc = 1;
 172			break;
 173		}
 
 174		fallthrough;
 175	case USB_SPEED_SUPER:
 176		if (gadget_is_superspeed(g)) {
 177			speed_desc = f->ss_descriptors;
 178			want_comp_desc = 1;
 179			break;
 180		}
 
 181		fallthrough;
 182	case USB_SPEED_HIGH:
 183		if (gadget_is_dualspeed(g)) {
 184			speed_desc = f->hs_descriptors;
 185			break;
 186		}
 
 187		fallthrough;
 188	default:
 189		speed_desc = f->fs_descriptors;
 190	}
 191
 
 
 
 
 
 
 192	/* find correct alternate setting descriptor */
 193	for_each_desc(speed_desc, d_spd, USB_DT_INTERFACE) {
 194		int_desc = (struct usb_interface_descriptor *)*d_spd;
 195
 196		if (int_desc->bAlternateSetting == alt) {
 197			speed_desc = d_spd;
 198			goto intf_found;
 199		}
 200	}
 201	return -EIO;
 202
 203intf_found:
 204	/* find descriptors */
 205	for_each_desc(speed_desc, d_spd, USB_DT_ENDPOINT) {
 206		chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
 207		if (chosen_desc->bEndpointAddress == _ep->address)
 208			goto ep_found;
 209	}
 210	return -EIO;
 211
 212ep_found:
 213	/* commit results */
 214	_ep->maxpacket = usb_endpoint_maxp(chosen_desc);
 215	_ep->desc = chosen_desc;
 216	_ep->comp_desc = NULL;
 217	_ep->maxburst = 0;
 218	_ep->mult = 1;
 219
 220	if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 221				usb_endpoint_xfer_int(_ep->desc)))
 222		_ep->mult = usb_endpoint_maxp_mult(_ep->desc);
 223
 224	if (!want_comp_desc)
 225		return 0;
 226
 227	/*
 228	 * Companion descriptor should follow EP descriptor
 229	 * USB 3.0 spec, #9.6.7
 230	 */
 231	comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
 232	if (!comp_desc ||
 233	    (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
 234		return -EIO;
 235	_ep->comp_desc = comp_desc;
 236	if (g->speed >= USB_SPEED_SUPER) {
 237		switch (usb_endpoint_type(_ep->desc)) {
 238		case USB_ENDPOINT_XFER_ISOC:
 239			/* mult: bits 1:0 of bmAttributes */
 240			_ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
 241			fallthrough;
 242		case USB_ENDPOINT_XFER_BULK:
 243		case USB_ENDPOINT_XFER_INT:
 244			_ep->maxburst = comp_desc->bMaxBurst + 1;
 245			break;
 246		default:
 247			if (comp_desc->bMaxBurst != 0) {
 248				struct usb_composite_dev *cdev;
 249
 250				cdev = get_gadget_data(g);
 251				ERROR(cdev, "ep0 bMaxBurst must be 0\n");
 252			}
 253			_ep->maxburst = 1;
 254			break;
 255		}
 256	}
 257	return 0;
 258}
 259EXPORT_SYMBOL_GPL(config_ep_by_speed_and_alt);
 260
 261/**
 262 * config_ep_by_speed() - configures the given endpoint
 263 * according to gadget speed.
 264 * @g: pointer to the gadget
 265 * @f: usb function
 266 * @_ep: the endpoint to configure
 267 *
 268 * Return: error code, 0 on success
 269 *
 270 * This function chooses the right descriptors for a given
 271 * endpoint according to gadget speed and saves it in the
 272 * endpoint desc field. If the endpoint already has a descriptor
 273 * assigned to it - overwrites it with currently corresponding
 274 * descriptor. The endpoint maxpacket field is updated according
 275 * to the chosen descriptor.
 276 * Note: the supplied function should hold all the descriptors
 277 * for supported speeds
 278 */
 279int config_ep_by_speed(struct usb_gadget *g,
 280			struct usb_function *f,
 281			struct usb_ep *_ep)
 282{
 283	return config_ep_by_speed_and_alt(g, f, _ep, 0);
 284}
 285EXPORT_SYMBOL_GPL(config_ep_by_speed);
 286
 287/**
 288 * usb_add_function() - add a function to a configuration
 289 * @config: the configuration
 290 * @function: the function being added
 291 * Context: single threaded during gadget setup
 292 *
 293 * After initialization, each configuration must have one or more
 294 * functions added to it.  Adding a function involves calling its @bind()
 295 * method to allocate resources such as interface and string identifiers
 296 * and endpoints.
 297 *
 298 * This function returns the value of the function's bind(), which is
 299 * zero for success else a negative errno value.
 300 */
 301int usb_add_function(struct usb_configuration *config,
 302		struct usb_function *function)
 303{
 304	int	value = -EINVAL;
 305
 306	DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
 307			function->name, function,
 308			config->label, config);
 309
 310	if (!function->set_alt || !function->disable)
 311		goto done;
 312
 313	function->config = config;
 314	list_add_tail(&function->list, &config->functions);
 315
 316	if (function->bind_deactivated) {
 317		value = usb_function_deactivate(function);
 318		if (value)
 319			goto done;
 320	}
 321
 322	/* REVISIT *require* function->bind? */
 323	if (function->bind) {
 324		value = function->bind(config, function);
 325		if (value < 0) {
 326			list_del(&function->list);
 327			function->config = NULL;
 328		}
 329	} else
 330		value = 0;
 331
 332	/* We allow configurations that don't work at both speeds.
 333	 * If we run into a lowspeed Linux system, treat it the same
 334	 * as full speed ... it's the function drivers that will need
 335	 * to avoid bulk and ISO transfers.
 336	 */
 337	if (!config->fullspeed && function->fs_descriptors)
 338		config->fullspeed = true;
 339	if (!config->highspeed && function->hs_descriptors)
 340		config->highspeed = true;
 341	if (!config->superspeed && function->ss_descriptors)
 342		config->superspeed = true;
 343	if (!config->superspeed_plus && function->ssp_descriptors)
 344		config->superspeed_plus = true;
 345
 346done:
 347	if (value)
 348		DBG(config->cdev, "adding '%s'/%p --> %d\n",
 349				function->name, function, value);
 350	return value;
 351}
 352EXPORT_SYMBOL_GPL(usb_add_function);
 353
 354void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
 355{
 356	if (f->disable)
 357		f->disable(f);
 358
 359	bitmap_zero(f->endpoints, 32);
 360	list_del(&f->list);
 361	if (f->unbind)
 362		f->unbind(c, f);
 363
 364	if (f->bind_deactivated)
 365		usb_function_activate(f);
 366}
 367EXPORT_SYMBOL_GPL(usb_remove_function);
 368
 369/**
 370 * usb_function_deactivate - prevent function and gadget enumeration
 371 * @function: the function that isn't yet ready to respond
 372 *
 373 * Blocks response of the gadget driver to host enumeration by
 374 * preventing the data line pullup from being activated.  This is
 375 * normally called during @bind() processing to change from the
 376 * initial "ready to respond" state, or when a required resource
 377 * becomes available.
 378 *
 379 * For example, drivers that serve as a passthrough to a userspace
 380 * daemon can block enumeration unless that daemon (such as an OBEX,
 381 * MTP, or print server) is ready to handle host requests.
 382 *
 383 * Not all systems support software control of their USB peripheral
 384 * data pullups.
 385 *
 386 * Returns zero on success, else negative errno.
 387 */
 388int usb_function_deactivate(struct usb_function *function)
 389{
 390	struct usb_composite_dev	*cdev = function->config->cdev;
 391	unsigned long			flags;
 392	int				status = 0;
 393
 394	spin_lock_irqsave(&cdev->lock, flags);
 395
 396	if (cdev->deactivations == 0) {
 397		spin_unlock_irqrestore(&cdev->lock, flags);
 398		status = usb_gadget_deactivate(cdev->gadget);
 399		spin_lock_irqsave(&cdev->lock, flags);
 400	}
 401	if (status == 0)
 402		cdev->deactivations++;
 403
 404	spin_unlock_irqrestore(&cdev->lock, flags);
 405	return status;
 406}
 407EXPORT_SYMBOL_GPL(usb_function_deactivate);
 408
 409/**
 410 * usb_function_activate - allow function and gadget enumeration
 411 * @function: function on which usb_function_activate() was called
 412 *
 413 * Reverses effect of usb_function_deactivate().  If no more functions
 414 * are delaying their activation, the gadget driver will respond to
 415 * host enumeration procedures.
 416 *
 417 * Returns zero on success, else negative errno.
 418 */
 419int usb_function_activate(struct usb_function *function)
 420{
 421	struct usb_composite_dev	*cdev = function->config->cdev;
 422	unsigned long			flags;
 423	int				status = 0;
 424
 425	spin_lock_irqsave(&cdev->lock, flags);
 426
 427	if (WARN_ON(cdev->deactivations == 0))
 428		status = -EINVAL;
 429	else {
 430		cdev->deactivations--;
 431		if (cdev->deactivations == 0) {
 432			spin_unlock_irqrestore(&cdev->lock, flags);
 433			status = usb_gadget_activate(cdev->gadget);
 434			spin_lock_irqsave(&cdev->lock, flags);
 435		}
 436	}
 437
 438	spin_unlock_irqrestore(&cdev->lock, flags);
 439	return status;
 440}
 441EXPORT_SYMBOL_GPL(usb_function_activate);
 442
 443/**
 444 * usb_interface_id() - allocate an unused interface ID
 445 * @config: configuration associated with the interface
 446 * @function: function handling the interface
 447 * Context: single threaded during gadget setup
 448 *
 449 * usb_interface_id() is called from usb_function.bind() callbacks to
 450 * allocate new interface IDs.  The function driver will then store that
 451 * ID in interface, association, CDC union, and other descriptors.  It
 452 * will also handle any control requests targeted at that interface,
 453 * particularly changing its altsetting via set_alt().  There may
 454 * also be class-specific or vendor-specific requests to handle.
 455 *
 456 * All interface identifier should be allocated using this routine, to
 457 * ensure that for example different functions don't wrongly assign
 458 * different meanings to the same identifier.  Note that since interface
 459 * identifiers are configuration-specific, functions used in more than
 460 * one configuration (or more than once in a given configuration) need
 461 * multiple versions of the relevant descriptors.
 462 *
 463 * Returns the interface ID which was allocated; or -ENODEV if no
 464 * more interface IDs can be allocated.
 465 */
 466int usb_interface_id(struct usb_configuration *config,
 467		struct usb_function *function)
 468{
 469	unsigned id = config->next_interface_id;
 470
 471	if (id < MAX_CONFIG_INTERFACES) {
 472		config->interface[id] = function;
 473		config->next_interface_id = id + 1;
 474		return id;
 475	}
 476	return -ENODEV;
 477}
 478EXPORT_SYMBOL_GPL(usb_interface_id);
 479
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 480static u8 encode_bMaxPower(enum usb_device_speed speed,
 481		struct usb_configuration *c)
 482{
 483	unsigned val;
 484
 485	if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
 486		val = c->MaxPower;
 487	else
 488		val = CONFIG_USB_GADGET_VBUS_DRAW;
 489	if (!val)
 490		return 0;
 491	if (speed < USB_SPEED_SUPER)
 492		return min(val, 500U) / 2;
 493	else
 494		/*
 495		 * USB 3.x supports up to 900mA, but since 900 isn't divisible
 496		 * by 8 the integral division will effectively cap to 896mA.
 497		 */
 498		return min(val, 900U) / 8;
 499}
 500
 
 
 
 
 
 
 
 
 
 
 
 
 
 501static int config_buf(struct usb_configuration *config,
 502		enum usb_device_speed speed, void *buf, u8 type)
 503{
 504	struct usb_config_descriptor	*c = buf;
 505	void				*next = buf + USB_DT_CONFIG_SIZE;
 506	int				len;
 507	struct usb_function		*f;
 508	int				status;
 509
 510	len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
 511	/* write the config descriptor */
 512	c = buf;
 513	c->bLength = USB_DT_CONFIG_SIZE;
 514	c->bDescriptorType = type;
 515	/* wTotalLength is written later */
 516	c->bNumInterfaces = config->next_interface_id;
 517	c->bConfigurationValue = config->bConfigurationValue;
 518	c->iConfiguration = config->iConfiguration;
 519	c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
 520	c->bMaxPower = encode_bMaxPower(speed, config);
 521
 522	/* There may be e.g. OTG descriptors */
 523	if (config->descriptors) {
 524		status = usb_descriptor_fillbuf(next, len,
 525				config->descriptors);
 526		if (status < 0)
 527			return status;
 528		len -= status;
 529		next += status;
 530	}
 531
 532	/* add each function's descriptors */
 533	list_for_each_entry(f, &config->functions, list) {
 534		struct usb_descriptor_header **descriptors;
 535
 536		descriptors = function_descriptors(f, speed);
 537		if (!descriptors)
 538			continue;
 539		status = usb_descriptor_fillbuf(next, len,
 540			(const struct usb_descriptor_header **) descriptors);
 541		if (status < 0)
 542			return status;
 543		len -= status;
 544		next += status;
 545	}
 546
 547	len = next - buf;
 548	c->wTotalLength = cpu_to_le16(len);
 549	return len;
 550}
 551
 552static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 553{
 554	struct usb_gadget		*gadget = cdev->gadget;
 555	struct usb_configuration	*c;
 556	struct list_head		*pos;
 557	u8				type = w_value >> 8;
 558	enum usb_device_speed		speed = USB_SPEED_UNKNOWN;
 559
 560	if (gadget->speed >= USB_SPEED_SUPER)
 561		speed = gadget->speed;
 562	else if (gadget_is_dualspeed(gadget)) {
 563		int	hs = 0;
 564		if (gadget->speed == USB_SPEED_HIGH)
 565			hs = 1;
 566		if (type == USB_DT_OTHER_SPEED_CONFIG)
 567			hs = !hs;
 568		if (hs)
 569			speed = USB_SPEED_HIGH;
 570
 571	}
 572
 573	/* This is a lookup by config *INDEX* */
 574	w_value &= 0xff;
 575
 576	pos = &cdev->configs;
 577	c = cdev->os_desc_config;
 578	if (c)
 579		goto check_config;
 580
 581	while ((pos = pos->next) !=  &cdev->configs) {
 582		c = list_entry(pos, typeof(*c), list);
 583
 584		/* skip OS Descriptors config which is handled separately */
 585		if (c == cdev->os_desc_config)
 586			continue;
 587
 588check_config:
 589		/* ignore configs that won't work at this speed */
 590		switch (speed) {
 591		case USB_SPEED_SUPER_PLUS:
 592			if (!c->superspeed_plus)
 593				continue;
 594			break;
 595		case USB_SPEED_SUPER:
 596			if (!c->superspeed)
 597				continue;
 598			break;
 599		case USB_SPEED_HIGH:
 600			if (!c->highspeed)
 601				continue;
 602			break;
 603		default:
 604			if (!c->fullspeed)
 605				continue;
 606		}
 607
 608		if (w_value == 0)
 609			return config_buf(c, speed, cdev->req->buf, type);
 610		w_value--;
 611	}
 612	return -EINVAL;
 613}
 614
 615static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 616{
 617	struct usb_gadget		*gadget = cdev->gadget;
 618	struct usb_configuration	*c;
 619	unsigned			count = 0;
 620	int				hs = 0;
 621	int				ss = 0;
 622	int				ssp = 0;
 623
 624	if (gadget_is_dualspeed(gadget)) {
 625		if (gadget->speed == USB_SPEED_HIGH)
 626			hs = 1;
 627		if (gadget->speed == USB_SPEED_SUPER)
 628			ss = 1;
 629		if (gadget->speed == USB_SPEED_SUPER_PLUS)
 630			ssp = 1;
 631		if (type == USB_DT_DEVICE_QUALIFIER)
 632			hs = !hs;
 633	}
 634	list_for_each_entry(c, &cdev->configs, list) {
 635		/* ignore configs that won't work at this speed */
 636		if (ssp) {
 637			if (!c->superspeed_plus)
 638				continue;
 639		} else if (ss) {
 640			if (!c->superspeed)
 641				continue;
 642		} else if (hs) {
 643			if (!c->highspeed)
 644				continue;
 645		} else {
 646			if (!c->fullspeed)
 647				continue;
 648		}
 649		count++;
 650	}
 651	return count;
 652}
 653
 654/**
 655 * bos_desc() - prepares the BOS descriptor.
 656 * @cdev: pointer to usb_composite device to generate the bos
 657 *	descriptor for
 658 *
 659 * This function generates the BOS (Binary Device Object)
 660 * descriptor and its device capabilities descriptors. The BOS
 661 * descriptor should be supported by a SuperSpeed device.
 662 */
 663static int bos_desc(struct usb_composite_dev *cdev)
 664{
 665	struct usb_ext_cap_descriptor	*usb_ext;
 666	struct usb_dcd_config_params	dcd_config_params;
 667	struct usb_bos_descriptor	*bos = cdev->req->buf;
 668	unsigned int			besl = 0;
 669
 670	bos->bLength = USB_DT_BOS_SIZE;
 671	bos->bDescriptorType = USB_DT_BOS;
 672
 673	bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
 674	bos->bNumDeviceCaps = 0;
 675
 676	/* Get Controller configuration */
 677	if (cdev->gadget->ops->get_config_params) {
 678		cdev->gadget->ops->get_config_params(cdev->gadget,
 679						     &dcd_config_params);
 680	} else {
 681		dcd_config_params.besl_baseline =
 682			USB_DEFAULT_BESL_UNSPECIFIED;
 683		dcd_config_params.besl_deep =
 684			USB_DEFAULT_BESL_UNSPECIFIED;
 685		dcd_config_params.bU1devExitLat =
 686			USB_DEFAULT_U1_DEV_EXIT_LAT;
 687		dcd_config_params.bU2DevExitLat =
 688			cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
 689	}
 690
 691	if (dcd_config_params.besl_baseline != USB_DEFAULT_BESL_UNSPECIFIED)
 692		besl = USB_BESL_BASELINE_VALID |
 693			USB_SET_BESL_BASELINE(dcd_config_params.besl_baseline);
 694
 695	if (dcd_config_params.besl_deep != USB_DEFAULT_BESL_UNSPECIFIED)
 696		besl |= USB_BESL_DEEP_VALID |
 697			USB_SET_BESL_DEEP(dcd_config_params.besl_deep);
 698
 699	/*
 700	 * A SuperSpeed device shall include the USB2.0 extension descriptor
 701	 * and shall support LPM when operating in USB2.0 HS mode.
 702	 */
 703	usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 704	bos->bNumDeviceCaps++;
 705	le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
 706	usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
 707	usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 708	usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
 709	usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
 710					    USB_BESL_SUPPORT | besl);
 
 
 711
 712	/*
 713	 * The Superspeed USB Capability descriptor shall be implemented by all
 714	 * SuperSpeed devices.
 715	 */
 716	if (gadget_is_superspeed(cdev->gadget)) {
 717		struct usb_ss_cap_descriptor *ss_cap;
 718
 719		ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 720		bos->bNumDeviceCaps++;
 721		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
 722		ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
 723		ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 724		ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
 725		ss_cap->bmAttributes = 0; /* LTM is not supported yet */
 726		ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
 727						      USB_FULL_SPEED_OPERATION |
 728						      USB_HIGH_SPEED_OPERATION |
 729						      USB_5GBPS_OPERATION);
 730		ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
 731		ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
 732		ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
 733	}
 734
 735	/* The SuperSpeedPlus USB Device Capability descriptor */
 736	if (gadget_is_superspeed_plus(cdev->gadget)) {
 737		struct usb_ssp_cap_descriptor *ssp_cap;
 738		u8 ssac = 1;
 739		u8 ssic;
 740		int i;
 741
 742		if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x2)
 743			ssac = 3;
 744
 745		/*
 746		 * Paired RX and TX sublink speed attributes share
 747		 * the same SSID.
 748		 */
 749		ssic = (ssac + 1) / 2 - 1;
 750
 751		ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
 752		bos->bNumDeviceCaps++;
 753
 754		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(ssac));
 755		ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(ssac);
 756		ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
 757		ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
 758		ssp_cap->bReserved = 0;
 759		ssp_cap->wReserved = 0;
 760
 761		ssp_cap->bmAttributes =
 762			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, ssac) |
 763				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, ssic));
 764
 765		ssp_cap->wFunctionalitySupport =
 766			cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, 0) |
 767				    FIELD_PREP(USB_SSP_MIN_RX_LANE_COUNT, 1) |
 768				    FIELD_PREP(USB_SSP_MIN_TX_LANE_COUNT, 1));
 769
 770		/*
 771		 * Use 1 SSID if the gadget supports up to gen2x1 or not
 772		 * specified:
 773		 * - SSID 0 for symmetric RX/TX sublink speed of 10 Gbps.
 774		 *
 775		 * Use 1 SSID if the gadget supports up to gen1x2:
 776		 * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
 777		 *
 778		 * Use 2 SSIDs if the gadget supports up to gen2x2:
 779		 * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
 780		 * - SSID 1 for symmetric RX/TX sublink speed of 10 Gbps.
 781		 */
 782		for (i = 0; i < ssac + 1; i++) {
 783			u8 ssid;
 784			u8 mantissa;
 785			u8 type;
 786
 787			ssid = i >> 1;
 788
 789			if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x1 ||
 790			    cdev->gadget->max_ssp_rate == USB_SSP_GEN_UNKNOWN)
 791				mantissa = 10;
 792			else
 793				mantissa = 5 << ssid;
 794
 795			if (i % 2)
 796				type = USB_SSP_SUBLINK_SPEED_ST_SYM_TX;
 797			else
 798				type = USB_SSP_SUBLINK_SPEED_ST_SYM_RX;
 799
 800			ssp_cap->bmSublinkSpeedAttr[i] =
 801				cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, ssid) |
 802					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE,
 803						       USB_SSP_SUBLINK_SPEED_LSE_GBPS) |
 804					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST, type) |
 805					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP,
 806						       USB_SSP_SUBLINK_SPEED_LP_SSP) |
 807					    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, mantissa));
 808		}
 809	}
 810
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 811	return le16_to_cpu(bos->wTotalLength);
 812}
 813
 814static void device_qual(struct usb_composite_dev *cdev)
 815{
 816	struct usb_qualifier_descriptor	*qual = cdev->req->buf;
 817
 818	qual->bLength = sizeof(*qual);
 819	qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
 820	/* POLICY: same bcdUSB and device type info at both speeds */
 821	qual->bcdUSB = cdev->desc.bcdUSB;
 822	qual->bDeviceClass = cdev->desc.bDeviceClass;
 823	qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 824	qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 825	/* ASSUME same EP0 fifo size at both speeds */
 826	qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 827	qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 828	qual->bRESERVED = 0;
 829}
 830
 831/*-------------------------------------------------------------------------*/
 832
 833static void reset_config(struct usb_composite_dev *cdev)
 834{
 835	struct usb_function		*f;
 836
 837	DBG(cdev, "reset config\n");
 838
 839	list_for_each_entry(f, &cdev->config->functions, list) {
 840		if (f->disable)
 841			f->disable(f);
 842
 
 
 
 843		bitmap_zero(f->endpoints, 32);
 844	}
 845	cdev->config = NULL;
 846	cdev->delayed_status = 0;
 847}
 848
 849static int set_config(struct usb_composite_dev *cdev,
 850		const struct usb_ctrlrequest *ctrl, unsigned number)
 851{
 852	struct usb_gadget	*gadget = cdev->gadget;
 853	struct usb_configuration *c = NULL;
 854	int			result = -EINVAL;
 855	unsigned		power = gadget_is_otg(gadget) ? 8 : 100;
 856	int			tmp;
 857
 858	if (number) {
 859		list_for_each_entry(c, &cdev->configs, list) {
 860			if (c->bConfigurationValue == number) {
 861				/*
 862				 * We disable the FDs of the previous
 863				 * configuration only if the new configuration
 864				 * is a valid one
 865				 */
 866				if (cdev->config)
 867					reset_config(cdev);
 868				result = 0;
 869				break;
 870			}
 
 871		}
 872		if (result < 0)
 873			goto done;
 874	} else { /* Zero configuration value - need to reset the config */
 875		if (cdev->config)
 876			reset_config(cdev);
 877		result = 0;
 878	}
 879
 880	DBG(cdev, "%s config #%d: %s\n",
 881	    usb_speed_string(gadget->speed),
 882	    number, c ? c->label : "unconfigured");
 883
 884	if (!c)
 885		goto done;
 886
 887	usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
 888	cdev->config = c;
 889
 890	/* Initialize all interfaces by setting them to altsetting zero. */
 891	for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
 892		struct usb_function	*f = c->interface[tmp];
 893		struct usb_descriptor_header **descriptors;
 894
 895		if (!f)
 896			break;
 897
 898		/*
 899		 * Record which endpoints are used by the function. This is used
 900		 * to dispatch control requests targeted at that endpoint to the
 901		 * function's setup callback instead of the current
 902		 * configuration's setup callback.
 903		 */
 904		descriptors = function_descriptors(f, gadget->speed);
 905
 906		for (; *descriptors; ++descriptors) {
 907			struct usb_endpoint_descriptor *ep;
 908			int addr;
 909
 910			if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
 911				continue;
 912
 913			ep = (struct usb_endpoint_descriptor *)*descriptors;
 914			addr = ((ep->bEndpointAddress & 0x80) >> 3)
 915			     |  (ep->bEndpointAddress & 0x0f);
 916			set_bit(addr, f->endpoints);
 917		}
 918
 919		result = f->set_alt(f, tmp, 0);
 920		if (result < 0) {
 921			DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
 922					tmp, f->name, f, result);
 923
 924			reset_config(cdev);
 925			goto done;
 926		}
 927
 928		if (result == USB_GADGET_DELAYED_STATUS) {
 929			DBG(cdev,
 930			 "%s: interface %d (%s) requested delayed status\n",
 931					__func__, tmp, f->name);
 932			cdev->delayed_status++;
 933			DBG(cdev, "delayed_status count %d\n",
 934					cdev->delayed_status);
 935		}
 936	}
 937
 938	/* when we return, be sure our power usage is valid */
 939	if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
 940		power = c->MaxPower;
 941	else
 942		power = CONFIG_USB_GADGET_VBUS_DRAW;
 943
 944	if (gadget->speed < USB_SPEED_SUPER)
 945		power = min(power, 500U);
 946	else
 947		power = min(power, 900U);
 
 
 
 
 
 948done:
 949	if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
 
 
 
 950		usb_gadget_set_selfpowered(gadget);
 951	else
 952		usb_gadget_clear_selfpowered(gadget);
 953
 954	usb_gadget_vbus_draw(gadget, power);
 955	if (result >= 0 && cdev->delayed_status)
 956		result = USB_GADGET_DELAYED_STATUS;
 957	return result;
 958}
 959
 960int usb_add_config_only(struct usb_composite_dev *cdev,
 961		struct usb_configuration *config)
 962{
 963	struct usb_configuration *c;
 964
 965	if (!config->bConfigurationValue)
 966		return -EINVAL;
 967
 968	/* Prevent duplicate configuration identifiers */
 969	list_for_each_entry(c, &cdev->configs, list) {
 970		if (c->bConfigurationValue == config->bConfigurationValue)
 971			return -EBUSY;
 972	}
 973
 974	config->cdev = cdev;
 975	list_add_tail(&config->list, &cdev->configs);
 976
 977	INIT_LIST_HEAD(&config->functions);
 978	config->next_interface_id = 0;
 979	memset(config->interface, 0, sizeof(config->interface));
 980
 981	return 0;
 982}
 983EXPORT_SYMBOL_GPL(usb_add_config_only);
 984
 985/**
 986 * usb_add_config() - add a configuration to a device.
 987 * @cdev: wraps the USB gadget
 988 * @config: the configuration, with bConfigurationValue assigned
 989 * @bind: the configuration's bind function
 990 * Context: single threaded during gadget setup
 991 *
 992 * One of the main tasks of a composite @bind() routine is to
 993 * add each of the configurations it supports, using this routine.
 994 *
 995 * This function returns the value of the configuration's @bind(), which
 996 * is zero for success else a negative errno value.  Binding configurations
 997 * assigns global resources including string IDs, and per-configuration
 998 * resources such as interface IDs and endpoints.
 999 */
1000int usb_add_config(struct usb_composite_dev *cdev,
1001		struct usb_configuration *config,
1002		int (*bind)(struct usb_configuration *))
1003{
1004	int				status = -EINVAL;
1005
1006	if (!bind)
1007		goto done;
1008
1009	DBG(cdev, "adding config #%u '%s'/%p\n",
1010			config->bConfigurationValue,
1011			config->label, config);
1012
1013	status = usb_add_config_only(cdev, config);
1014	if (status)
1015		goto done;
1016
1017	status = bind(config);
 
 
 
 
1018	if (status < 0) {
1019		while (!list_empty(&config->functions)) {
1020			struct usb_function		*f;
1021
1022			f = list_first_entry(&config->functions,
1023					struct usb_function, list);
1024			list_del(&f->list);
1025			if (f->unbind) {
1026				DBG(cdev, "unbind function '%s'/%p\n",
1027					f->name, f);
1028				f->unbind(config, f);
1029				/* may free memory for "f" */
1030			}
1031		}
1032		list_del(&config->list);
1033		config->cdev = NULL;
1034	} else {
1035		unsigned	i;
1036
1037		DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
1038			config->bConfigurationValue, config,
1039			config->superspeed_plus ? " superplus" : "",
1040			config->superspeed ? " super" : "",
1041			config->highspeed ? " high" : "",
1042			config->fullspeed
1043				? (gadget_is_dualspeed(cdev->gadget)
1044					? " full"
1045					: " full/low")
1046				: "");
1047
1048		for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
1049			struct usb_function	*f = config->interface[i];
1050
1051			if (!f)
1052				continue;
1053			DBG(cdev, "  interface %d = %s/%p\n",
1054				i, f->name, f);
1055		}
1056	}
1057
1058	/* set_alt(), or next bind(), sets up ep->claimed as needed */
1059	usb_ep_autoconfig_reset(cdev->gadget);
1060
1061done:
1062	if (status)
1063		DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
1064				config->bConfigurationValue, status);
1065	return status;
1066}
1067EXPORT_SYMBOL_GPL(usb_add_config);
1068
1069static void remove_config(struct usb_composite_dev *cdev,
1070			      struct usb_configuration *config)
1071{
1072	while (!list_empty(&config->functions)) {
1073		struct usb_function		*f;
1074
1075		f = list_first_entry(&config->functions,
1076				struct usb_function, list);
1077
1078		usb_remove_function(config, f);
1079	}
1080	list_del(&config->list);
1081	if (config->unbind) {
1082		DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
1083		config->unbind(config);
1084			/* may free memory for "c" */
1085	}
1086}
1087
1088/**
1089 * usb_remove_config() - remove a configuration from a device.
1090 * @cdev: wraps the USB gadget
1091 * @config: the configuration
1092 *
1093 * Drivers must call usb_gadget_disconnect before calling this function
1094 * to disconnect the device from the host and make sure the host will not
1095 * try to enumerate the device while we are changing the config list.
1096 */
1097void usb_remove_config(struct usb_composite_dev *cdev,
1098		      struct usb_configuration *config)
1099{
1100	unsigned long flags;
1101
1102	spin_lock_irqsave(&cdev->lock, flags);
1103
1104	if (cdev->config == config)
1105		reset_config(cdev);
1106
1107	spin_unlock_irqrestore(&cdev->lock, flags);
1108
1109	remove_config(cdev, config);
1110}
1111
1112/*-------------------------------------------------------------------------*/
1113
1114/* We support strings in multiple languages ... string descriptor zero
1115 * says which languages are supported.  The typical case will be that
1116 * only one language (probably English) is used, with i18n handled on
1117 * the host side.
1118 */
1119
1120static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1121{
1122	const struct usb_gadget_strings	*s;
1123	__le16				language;
1124	__le16				*tmp;
1125
1126	while (*sp) {
1127		s = *sp;
1128		language = cpu_to_le16(s->language);
1129		for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) {
1130			if (*tmp == language)
1131				goto repeat;
1132		}
1133		*tmp++ = language;
1134repeat:
1135		sp++;
1136	}
1137}
1138
1139static int lookup_string(
1140	struct usb_gadget_strings	**sp,
1141	void				*buf,
1142	u16				language,
1143	int				id
1144)
1145{
1146	struct usb_gadget_strings	*s;
1147	int				value;
1148
1149	while (*sp) {
1150		s = *sp++;
1151		if (s->language != language)
1152			continue;
1153		value = usb_gadget_get_string(s, id, buf);
1154		if (value > 0)
1155			return value;
1156	}
1157	return -EINVAL;
1158}
1159
1160static int get_string(struct usb_composite_dev *cdev,
1161		void *buf, u16 language, int id)
1162{
1163	struct usb_composite_driver	*composite = cdev->driver;
1164	struct usb_gadget_string_container *uc;
1165	struct usb_configuration	*c;
1166	struct usb_function		*f;
1167	int				len;
1168
1169	/* Yes, not only is USB's i18n support probably more than most
1170	 * folk will ever care about ... also, it's all supported here.
1171	 * (Except for UTF8 support for Unicode's "Astral Planes".)
1172	 */
1173
1174	/* 0 == report all available language codes */
1175	if (id == 0) {
1176		struct usb_string_descriptor	*s = buf;
1177		struct usb_gadget_strings	**sp;
1178
1179		memset(s, 0, 256);
1180		s->bDescriptorType = USB_DT_STRING;
1181
1182		sp = composite->strings;
1183		if (sp)
1184			collect_langs(sp, s->wData);
1185
1186		list_for_each_entry(c, &cdev->configs, list) {
1187			sp = c->strings;
1188			if (sp)
1189				collect_langs(sp, s->wData);
1190
1191			list_for_each_entry(f, &c->functions, list) {
1192				sp = f->strings;
1193				if (sp)
1194					collect_langs(sp, s->wData);
1195			}
1196		}
1197		list_for_each_entry(uc, &cdev->gstrings, list) {
1198			struct usb_gadget_strings **sp;
1199
1200			sp = get_containers_gs(uc);
1201			collect_langs(sp, s->wData);
1202		}
1203
1204		for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++)
1205			continue;
1206		if (!len)
1207			return -EINVAL;
1208
1209		s->bLength = 2 * (len + 1);
1210		return s->bLength;
1211	}
1212
1213	if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1214		struct usb_os_string *b = buf;
1215		b->bLength = sizeof(*b);
1216		b->bDescriptorType = USB_DT_STRING;
1217		compiletime_assert(
1218			sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1219			"qwSignature size must be equal to qw_sign");
1220		memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1221		b->bMS_VendorCode = cdev->b_vendor_code;
1222		b->bPad = 0;
1223		return sizeof(*b);
1224	}
1225
1226	list_for_each_entry(uc, &cdev->gstrings, list) {
1227		struct usb_gadget_strings **sp;
1228
1229		sp = get_containers_gs(uc);
1230		len = lookup_string(sp, buf, language, id);
1231		if (len > 0)
1232			return len;
1233	}
1234
1235	/* String IDs are device-scoped, so we look up each string
1236	 * table we're told about.  These lookups are infrequent;
1237	 * simpler-is-better here.
1238	 */
1239	if (composite->strings) {
1240		len = lookup_string(composite->strings, buf, language, id);
1241		if (len > 0)
1242			return len;
1243	}
1244	list_for_each_entry(c, &cdev->configs, list) {
1245		if (c->strings) {
1246			len = lookup_string(c->strings, buf, language, id);
1247			if (len > 0)
1248				return len;
1249		}
1250		list_for_each_entry(f, &c->functions, list) {
1251			if (!f->strings)
1252				continue;
1253			len = lookup_string(f->strings, buf, language, id);
1254			if (len > 0)
1255				return len;
1256		}
1257	}
1258	return -EINVAL;
1259}
1260
1261/**
1262 * usb_string_id() - allocate an unused string ID
1263 * @cdev: the device whose string descriptor IDs are being allocated
1264 * Context: single threaded during gadget setup
1265 *
1266 * @usb_string_id() is called from bind() callbacks to allocate
1267 * string IDs.  Drivers for functions, configurations, or gadgets will
1268 * then store that ID in the appropriate descriptors and string table.
1269 *
1270 * All string identifier should be allocated using this,
1271 * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1272 * that for example different functions don't wrongly assign different
1273 * meanings to the same identifier.
1274 */
1275int usb_string_id(struct usb_composite_dev *cdev)
1276{
1277	if (cdev->next_string_id < 254) {
1278		/* string id 0 is reserved by USB spec for list of
1279		 * supported languages */
1280		/* 255 reserved as well? -- mina86 */
1281		cdev->next_string_id++;
1282		return cdev->next_string_id;
1283	}
1284	return -ENODEV;
1285}
1286EXPORT_SYMBOL_GPL(usb_string_id);
1287
1288/**
1289 * usb_string_ids_tab() - allocate unused string IDs in batch
1290 * @cdev: the device whose string descriptor IDs are being allocated
1291 * @str: an array of usb_string objects to assign numbers to
1292 * Context: single threaded during gadget setup
1293 *
1294 * @usb_string_ids() is called from bind() callbacks to allocate
1295 * string IDs.  Drivers for functions, configurations, or gadgets will
1296 * then copy IDs from the string table to the appropriate descriptors
1297 * and string table for other languages.
1298 *
1299 * All string identifier should be allocated using this,
1300 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1301 * example different functions don't wrongly assign different meanings
1302 * to the same identifier.
1303 */
1304int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1305{
1306	int next = cdev->next_string_id;
1307
1308	for (; str->s; ++str) {
1309		if (unlikely(next >= 254))
1310			return -ENODEV;
1311		str->id = ++next;
1312	}
1313
1314	cdev->next_string_id = next;
1315
1316	return 0;
1317}
1318EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1319
1320static struct usb_gadget_string_container *copy_gadget_strings(
1321		struct usb_gadget_strings **sp, unsigned n_gstrings,
1322		unsigned n_strings)
1323{
1324	struct usb_gadget_string_container *uc;
1325	struct usb_gadget_strings **gs_array;
1326	struct usb_gadget_strings *gs;
1327	struct usb_string *s;
1328	unsigned mem;
1329	unsigned n_gs;
1330	unsigned n_s;
1331	void *stash;
1332
1333	mem = sizeof(*uc);
1334	mem += sizeof(void *) * (n_gstrings + 1);
1335	mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1336	mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1337	uc = kmalloc(mem, GFP_KERNEL);
1338	if (!uc)
1339		return ERR_PTR(-ENOMEM);
1340	gs_array = get_containers_gs(uc);
1341	stash = uc->stash;
1342	stash += sizeof(void *) * (n_gstrings + 1);
1343	for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1344		struct usb_string *org_s;
1345
1346		gs_array[n_gs] = stash;
1347		gs = gs_array[n_gs];
1348		stash += sizeof(struct usb_gadget_strings);
1349		gs->language = sp[n_gs]->language;
1350		gs->strings = stash;
1351		org_s = sp[n_gs]->strings;
1352
1353		for (n_s = 0; n_s < n_strings; n_s++) {
1354			s = stash;
1355			stash += sizeof(struct usb_string);
1356			if (org_s->s)
1357				s->s = org_s->s;
1358			else
1359				s->s = "";
1360			org_s++;
1361		}
1362		s = stash;
1363		s->s = NULL;
1364		stash += sizeof(struct usb_string);
1365
1366	}
1367	gs_array[n_gs] = NULL;
1368	return uc;
1369}
1370
1371/**
1372 * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1373 * @cdev: the device whose string descriptor IDs are being allocated
1374 * and attached.
1375 * @sp: an array of usb_gadget_strings to attach.
1376 * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1377 *
1378 * This function will create a deep copy of usb_gadget_strings and usb_string
1379 * and attach it to the cdev. The actual string (usb_string.s) will not be
1380 * copied but only a referenced will be made. The struct usb_gadget_strings
1381 * array may contain multiple languages and should be NULL terminated.
1382 * The ->language pointer of each struct usb_gadget_strings has to contain the
1383 * same amount of entries.
1384 * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1385 * usb_string entry of es-ES contains the translation of the first usb_string
1386 * entry of en-US. Therefore both entries become the same id assign.
1387 */
1388struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1389		struct usb_gadget_strings **sp, unsigned n_strings)
1390{
1391	struct usb_gadget_string_container *uc;
1392	struct usb_gadget_strings **n_gs;
1393	unsigned n_gstrings = 0;
1394	unsigned i;
1395	int ret;
1396
1397	for (i = 0; sp[i]; i++)
1398		n_gstrings++;
1399
1400	if (!n_gstrings)
1401		return ERR_PTR(-EINVAL);
1402
1403	uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1404	if (IS_ERR(uc))
1405		return ERR_CAST(uc);
1406
1407	n_gs = get_containers_gs(uc);
1408	ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1409	if (ret)
1410		goto err;
1411
1412	for (i = 1; i < n_gstrings; i++) {
1413		struct usb_string *m_s;
1414		struct usb_string *s;
1415		unsigned n;
1416
1417		m_s = n_gs[0]->strings;
1418		s = n_gs[i]->strings;
1419		for (n = 0; n < n_strings; n++) {
1420			s->id = m_s->id;
1421			s++;
1422			m_s++;
1423		}
1424	}
1425	list_add_tail(&uc->list, &cdev->gstrings);
1426	return n_gs[0]->strings;
1427err:
1428	kfree(uc);
1429	return ERR_PTR(ret);
1430}
1431EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1432
1433/**
1434 * usb_string_ids_n() - allocate unused string IDs in batch
1435 * @c: the device whose string descriptor IDs are being allocated
1436 * @n: number of string IDs to allocate
1437 * Context: single threaded during gadget setup
1438 *
1439 * Returns the first requested ID.  This ID and next @n-1 IDs are now
1440 * valid IDs.  At least provided that @n is non-zero because if it
1441 * is, returns last requested ID which is now very useful information.
1442 *
1443 * @usb_string_ids_n() is called from bind() callbacks to allocate
1444 * string IDs.  Drivers for functions, configurations, or gadgets will
1445 * then store that ID in the appropriate descriptors and string table.
1446 *
1447 * All string identifier should be allocated using this,
1448 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1449 * example different functions don't wrongly assign different meanings
1450 * to the same identifier.
1451 */
1452int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1453{
1454	unsigned next = c->next_string_id;
1455	if (unlikely(n > 254 || (unsigned)next + n > 254))
1456		return -ENODEV;
1457	c->next_string_id += n;
1458	return next + 1;
1459}
1460EXPORT_SYMBOL_GPL(usb_string_ids_n);
1461
1462/*-------------------------------------------------------------------------*/
1463
1464static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1465{
1466	struct usb_composite_dev *cdev;
1467
1468	if (req->status || req->actual != req->length)
1469		DBG((struct usb_composite_dev *) ep->driver_data,
1470				"setup complete --> %d, %d/%d\n",
1471				req->status, req->actual, req->length);
1472
1473	/*
1474	 * REVIST The same ep0 requests are shared with function drivers
1475	 * so they don't have to maintain the same ->complete() stubs.
1476	 *
1477	 * Because of that, we need to check for the validity of ->context
1478	 * here, even though we know we've set it to something useful.
1479	 */
1480	if (!req->context)
1481		return;
1482
1483	cdev = req->context;
1484
1485	if (cdev->req == req)
1486		cdev->setup_pending = false;
1487	else if (cdev->os_desc_req == req)
1488		cdev->os_desc_pending = false;
1489	else
1490		WARN(1, "unknown request %p\n", req);
1491}
1492
1493static int composite_ep0_queue(struct usb_composite_dev *cdev,
1494		struct usb_request *req, gfp_t gfp_flags)
1495{
1496	int ret;
1497
1498	ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1499	if (ret == 0) {
1500		if (cdev->req == req)
1501			cdev->setup_pending = true;
1502		else if (cdev->os_desc_req == req)
1503			cdev->os_desc_pending = true;
1504		else
1505			WARN(1, "unknown request %p\n", req);
1506	}
1507
1508	return ret;
1509}
1510
1511static int count_ext_compat(struct usb_configuration *c)
1512{
1513	int i, res;
1514
1515	res = 0;
1516	for (i = 0; i < c->next_interface_id; ++i) {
1517		struct usb_function *f;
1518		int j;
1519
1520		f = c->interface[i];
1521		for (j = 0; j < f->os_desc_n; ++j) {
1522			struct usb_os_desc *d;
1523
1524			if (i != f->os_desc_table[j].if_id)
1525				continue;
1526			d = f->os_desc_table[j].os_desc;
1527			if (d && d->ext_compat_id)
1528				++res;
1529		}
1530	}
1531	BUG_ON(res > 255);
1532	return res;
1533}
1534
1535static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1536{
1537	int i, count;
1538
1539	count = 16;
1540	buf += 16;
1541	for (i = 0; i < c->next_interface_id; ++i) {
1542		struct usb_function *f;
1543		int j;
1544
1545		f = c->interface[i];
1546		for (j = 0; j < f->os_desc_n; ++j) {
1547			struct usb_os_desc *d;
1548
1549			if (i != f->os_desc_table[j].if_id)
1550				continue;
1551			d = f->os_desc_table[j].os_desc;
1552			if (d && d->ext_compat_id) {
1553				*buf++ = i;
1554				*buf++ = 0x01;
1555				memcpy(buf, d->ext_compat_id, 16);
1556				buf += 22;
1557			} else {
1558				++buf;
1559				*buf = 0x01;
1560				buf += 23;
1561			}
1562			count += 24;
1563			if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1564				return count;
1565		}
1566	}
1567
1568	return count;
1569}
1570
1571static int count_ext_prop(struct usb_configuration *c, int interface)
1572{
1573	struct usb_function *f;
1574	int j;
1575
1576	f = c->interface[interface];
1577	for (j = 0; j < f->os_desc_n; ++j) {
1578		struct usb_os_desc *d;
1579
1580		if (interface != f->os_desc_table[j].if_id)
1581			continue;
1582		d = f->os_desc_table[j].os_desc;
1583		if (d && d->ext_compat_id)
1584			return d->ext_prop_count;
1585	}
1586	return 0;
1587}
1588
1589static int len_ext_prop(struct usb_configuration *c, int interface)
1590{
1591	struct usb_function *f;
1592	struct usb_os_desc *d;
1593	int j, res;
1594
1595	res = 10; /* header length */
1596	f = c->interface[interface];
1597	for (j = 0; j < f->os_desc_n; ++j) {
1598		if (interface != f->os_desc_table[j].if_id)
1599			continue;
1600		d = f->os_desc_table[j].os_desc;
1601		if (d)
1602			return min(res + d->ext_prop_len, 4096);
1603	}
1604	return res;
1605}
1606
1607static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1608{
1609	struct usb_function *f;
1610	struct usb_os_desc *d;
1611	struct usb_os_desc_ext_prop *ext_prop;
1612	int j, count, n, ret;
1613
1614	f = c->interface[interface];
1615	count = 10; /* header length */
1616	buf += 10;
1617	for (j = 0; j < f->os_desc_n; ++j) {
1618		if (interface != f->os_desc_table[j].if_id)
1619			continue;
1620		d = f->os_desc_table[j].os_desc;
1621		if (d)
1622			list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1623				n = ext_prop->data_len +
1624					ext_prop->name_len + 14;
1625				if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1626					return count;
1627				usb_ext_prop_put_size(buf, n);
1628				usb_ext_prop_put_type(buf, ext_prop->type);
1629				ret = usb_ext_prop_put_name(buf, ext_prop->name,
1630							    ext_prop->name_len);
1631				if (ret < 0)
1632					return ret;
1633				switch (ext_prop->type) {
1634				case USB_EXT_PROP_UNICODE:
1635				case USB_EXT_PROP_UNICODE_ENV:
1636				case USB_EXT_PROP_UNICODE_LINK:
1637					usb_ext_prop_put_unicode(buf, ret,
1638							 ext_prop->data,
1639							 ext_prop->data_len);
1640					break;
1641				case USB_EXT_PROP_BINARY:
1642					usb_ext_prop_put_binary(buf, ret,
1643							ext_prop->data,
1644							ext_prop->data_len);
1645					break;
1646				case USB_EXT_PROP_LE32:
1647					/* not implemented */
1648				case USB_EXT_PROP_BE32:
1649					/* not implemented */
1650				default:
1651					return -EINVAL;
1652				}
1653				buf += n;
1654				count += n;
1655			}
1656	}
1657
1658	return count;
1659}
1660
1661/*
1662 * The setup() callback implements all the ep0 functionality that's
1663 * not handled lower down, in hardware or the hardware driver(like
1664 * device and endpoint feature flags, and their status).  It's all
1665 * housekeeping for the gadget function we're implementing.  Most of
1666 * the work is in config and function specific setup.
1667 */
1668int
1669composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1670{
1671	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
1672	struct usb_request		*req = cdev->req;
1673	int				value = -EOPNOTSUPP;
1674	int				status = 0;
1675	u16				w_index = le16_to_cpu(ctrl->wIndex);
1676	u8				intf = w_index & 0xFF;
1677	u16				w_value = le16_to_cpu(ctrl->wValue);
1678	u16				w_length = le16_to_cpu(ctrl->wLength);
1679	struct usb_function		*f = NULL;
 
1680	u8				endp;
1681
 
 
 
 
 
 
 
 
 
 
 
 
1682	/* partial re-init of the response message; the function or the
1683	 * gadget might need to intercept e.g. a control-OUT completion
1684	 * when we delegate to it.
1685	 */
1686	req->zero = 0;
1687	req->context = cdev;
1688	req->complete = composite_setup_complete;
1689	req->length = 0;
1690	gadget->ep0->driver_data = cdev;
1691
1692	/*
1693	 * Don't let non-standard requests match any of the cases below
1694	 * by accident.
1695	 */
1696	if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1697		goto unknown;
1698
1699	switch (ctrl->bRequest) {
1700
1701	/* we handle all standard USB descriptors */
1702	case USB_REQ_GET_DESCRIPTOR:
1703		if (ctrl->bRequestType != USB_DIR_IN)
1704			goto unknown;
1705		switch (w_value >> 8) {
1706
1707		case USB_DT_DEVICE:
1708			cdev->desc.bNumConfigurations =
1709				count_configs(cdev, USB_DT_DEVICE);
1710			cdev->desc.bMaxPacketSize0 =
1711				cdev->gadget->ep0->maxpacket;
1712			if (gadget_is_superspeed(gadget)) {
1713				if (gadget->speed >= USB_SPEED_SUPER) {
1714					cdev->desc.bcdUSB = cpu_to_le16(0x0320);
1715					cdev->desc.bMaxPacketSize0 = 9;
1716				} else {
1717					cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1718				}
1719			} else {
1720				if (gadget->lpm_capable)
1721					cdev->desc.bcdUSB = cpu_to_le16(0x0201);
1722				else
1723					cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1724			}
1725
1726			value = min(w_length, (u16) sizeof cdev->desc);
1727			memcpy(req->buf, &cdev->desc, value);
1728			break;
1729		case USB_DT_DEVICE_QUALIFIER:
1730			if (!gadget_is_dualspeed(gadget) ||
1731			    gadget->speed >= USB_SPEED_SUPER)
1732				break;
1733			device_qual(cdev);
1734			value = min_t(int, w_length,
1735				sizeof(struct usb_qualifier_descriptor));
1736			break;
1737		case USB_DT_OTHER_SPEED_CONFIG:
1738			if (!gadget_is_dualspeed(gadget) ||
1739			    gadget->speed >= USB_SPEED_SUPER)
1740				break;
1741			fallthrough;
1742		case USB_DT_CONFIG:
1743			value = config_desc(cdev, w_value);
1744			if (value >= 0)
1745				value = min(w_length, (u16) value);
1746			break;
1747		case USB_DT_STRING:
1748			value = get_string(cdev, req->buf,
1749					w_index, w_value & 0xff);
1750			if (value >= 0)
1751				value = min(w_length, (u16) value);
1752			break;
1753		case USB_DT_BOS:
1754			if (gadget_is_superspeed(gadget) ||
1755			    gadget->lpm_capable) {
1756				value = bos_desc(cdev);
1757				value = min(w_length, (u16) value);
1758			}
1759			break;
1760		case USB_DT_OTG:
1761			if (gadget_is_otg(gadget)) {
1762				struct usb_configuration *config;
1763				int otg_desc_len = 0;
1764
1765				if (cdev->config)
1766					config = cdev->config;
1767				else
1768					config = list_first_entry(
1769							&cdev->configs,
1770						struct usb_configuration, list);
1771				if (!config)
1772					goto done;
1773
1774				if (gadget->otg_caps &&
1775					(gadget->otg_caps->otg_rev >= 0x0200))
1776					otg_desc_len += sizeof(
1777						struct usb_otg20_descriptor);
1778				else
1779					otg_desc_len += sizeof(
1780						struct usb_otg_descriptor);
1781
1782				value = min_t(int, w_length, otg_desc_len);
1783				memcpy(req->buf, config->descriptors[0], value);
1784			}
1785			break;
1786		}
1787		break;
1788
1789	/* any number of configs can work */
1790	case USB_REQ_SET_CONFIGURATION:
1791		if (ctrl->bRequestType != 0)
1792			goto unknown;
1793		if (gadget_is_otg(gadget)) {
1794			if (gadget->a_hnp_support)
1795				DBG(cdev, "HNP available\n");
1796			else if (gadget->a_alt_hnp_support)
1797				DBG(cdev, "HNP on another port\n");
1798			else
1799				VDBG(cdev, "HNP inactive\n");
1800		}
1801		spin_lock(&cdev->lock);
1802		value = set_config(cdev, ctrl, w_value);
1803		spin_unlock(&cdev->lock);
1804		break;
1805	case USB_REQ_GET_CONFIGURATION:
1806		if (ctrl->bRequestType != USB_DIR_IN)
1807			goto unknown;
1808		if (cdev->config)
1809			*(u8 *)req->buf = cdev->config->bConfigurationValue;
1810		else
1811			*(u8 *)req->buf = 0;
1812		value = min(w_length, (u16) 1);
1813		break;
1814
1815	/* function drivers must handle get/set altsetting */
1816	case USB_REQ_SET_INTERFACE:
1817		if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1818			goto unknown;
1819		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1820			break;
1821		f = cdev->config->interface[intf];
1822		if (!f)
1823			break;
1824
1825		/*
1826		 * If there's no get_alt() method, we know only altsetting zero
1827		 * works. There is no need to check if set_alt() is not NULL
1828		 * as we check this in usb_add_function().
1829		 */
1830		if (w_value && !f->get_alt)
1831			break;
1832
1833		spin_lock(&cdev->lock);
1834		value = f->set_alt(f, w_index, w_value);
1835		if (value == USB_GADGET_DELAYED_STATUS) {
1836			DBG(cdev,
1837			 "%s: interface %d (%s) requested delayed status\n",
1838					__func__, intf, f->name);
1839			cdev->delayed_status++;
1840			DBG(cdev, "delayed_status count %d\n",
1841					cdev->delayed_status);
1842		}
1843		spin_unlock(&cdev->lock);
1844		break;
1845	case USB_REQ_GET_INTERFACE:
1846		if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1847			goto unknown;
1848		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1849			break;
1850		f = cdev->config->interface[intf];
1851		if (!f)
1852			break;
1853		/* lots of interfaces only need altsetting zero... */
1854		value = f->get_alt ? f->get_alt(f, w_index) : 0;
1855		if (value < 0)
1856			break;
1857		*((u8 *)req->buf) = value;
1858		value = min(w_length, (u16) 1);
1859		break;
1860	case USB_REQ_GET_STATUS:
1861		if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1862						(w_index == OTG_STS_SELECTOR)) {
1863			if (ctrl->bRequestType != (USB_DIR_IN |
1864							USB_RECIP_DEVICE))
1865				goto unknown;
1866			*((u8 *)req->buf) = gadget->host_request_flag;
1867			value = 1;
1868			break;
1869		}
1870
1871		/*
1872		 * USB 3.0 additions:
1873		 * Function driver should handle get_status request. If such cb
1874		 * wasn't supplied we respond with default value = 0
1875		 * Note: function driver should supply such cb only for the
1876		 * first interface of the function
1877		 */
1878		if (!gadget_is_superspeed(gadget))
1879			goto unknown;
1880		if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1881			goto unknown;
1882		value = 2;	/* This is the length of the get_status reply */
1883		put_unaligned_le16(0, req->buf);
1884		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1885			break;
1886		f = cdev->config->interface[intf];
1887		if (!f)
1888			break;
1889		status = f->get_status ? f->get_status(f) : 0;
1890		if (status < 0)
1891			break;
 
 
 
 
 
 
 
 
 
 
 
1892		put_unaligned_le16(status & 0x0000ffff, req->buf);
1893		break;
1894	/*
1895	 * Function drivers should handle SetFeature/ClearFeature
1896	 * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1897	 * only for the first interface of the function
1898	 */
1899	case USB_REQ_CLEAR_FEATURE:
1900	case USB_REQ_SET_FEATURE:
1901		if (!gadget_is_superspeed(gadget))
1902			goto unknown;
1903		if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1904			goto unknown;
1905		switch (w_value) {
1906		case USB_INTRF_FUNC_SUSPEND:
1907			if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1908				break;
1909			f = cdev->config->interface[intf];
1910			if (!f)
1911				break;
1912			value = 0;
1913			if (f->func_suspend)
1914				value = f->func_suspend(f, w_index >> 8);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1915			if (value < 0) {
1916				ERROR(cdev,
1917				      "func_suspend() returned error %d\n",
1918				      value);
1919				value = 0;
1920			}
1921			break;
1922		}
1923		break;
1924	default:
1925unknown:
1926		/*
1927		 * OS descriptors handling
1928		 */
1929		if (cdev->use_os_string && cdev->os_desc_config &&
1930		    (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1931		    ctrl->bRequest == cdev->b_vendor_code) {
1932			struct usb_configuration	*os_desc_cfg;
1933			u8				*buf;
1934			int				interface;
1935			int				count = 0;
1936
1937			req = cdev->os_desc_req;
1938			req->context = cdev;
1939			req->complete = composite_setup_complete;
1940			buf = req->buf;
1941			os_desc_cfg = cdev->os_desc_config;
1942			w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
1943			memset(buf, 0, w_length);
1944			buf[5] = 0x01;
1945			switch (ctrl->bRequestType & USB_RECIP_MASK) {
 
 
 
 
 
 
 
 
 
 
 
 
1946			case USB_RECIP_DEVICE:
1947				if (w_index != 0x4 || (w_value >> 8))
1948					break;
1949				buf[6] = w_index;
1950				/* Number of ext compat interfaces */
1951				count = count_ext_compat(os_desc_cfg);
1952				buf[8] = count;
1953				count *= 24; /* 24 B/ext compat desc */
1954				count += 16; /* header */
1955				put_unaligned_le32(count, buf);
1956				value = w_length;
1957				if (w_length > 0x10) {
1958					value = fill_ext_compat(os_desc_cfg, buf);
1959					value = min_t(u16, w_length, value);
1960				}
1961				break;
1962			case USB_RECIP_INTERFACE:
1963				if (w_index != 0x5 || (w_value >> 8))
1964					break;
1965				interface = w_value & 0xFF;
 
 
 
1966				buf[6] = w_index;
1967				count = count_ext_prop(os_desc_cfg,
1968					interface);
1969				put_unaligned_le16(count, buf + 8);
1970				count = len_ext_prop(os_desc_cfg,
1971					interface);
1972				put_unaligned_le32(count, buf);
1973				value = w_length;
1974				if (w_length > 0x0A) {
1975					value = fill_ext_prop(os_desc_cfg,
1976							      interface, buf);
1977					if (value >= 0)
1978						value = min_t(u16, w_length, value);
1979				}
1980				break;
1981			}
1982
1983			goto check_value;
1984		}
1985
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1986		VDBG(cdev,
1987			"non-core control req%02x.%02x v%04x i%04x l%d\n",
1988			ctrl->bRequestType, ctrl->bRequest,
1989			w_value, w_index, w_length);
1990
1991		/* functions always handle their interfaces and endpoints...
1992		 * punt other recipients (other, WUSB, ...) to the current
1993		 * configuration code.
1994		 */
1995		if (cdev->config) {
1996			list_for_each_entry(f, &cdev->config->functions, list)
1997				if (f->req_match &&
1998				    f->req_match(f, ctrl, false))
1999					goto try_fun_setup;
2000		} else {
2001			struct usb_configuration *c;
2002			list_for_each_entry(c, &cdev->configs, list)
2003				list_for_each_entry(f, &c->functions, list)
2004					if (f->req_match &&
2005					    f->req_match(f, ctrl, true))
2006						goto try_fun_setup;
2007		}
2008		f = NULL;
2009
2010		switch (ctrl->bRequestType & USB_RECIP_MASK) {
2011		case USB_RECIP_INTERFACE:
2012			if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
2013				break;
2014			f = cdev->config->interface[intf];
2015			break;
2016
2017		case USB_RECIP_ENDPOINT:
2018			if (!cdev->config)
2019				break;
2020			endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
2021			list_for_each_entry(f, &cdev->config->functions, list) {
2022				if (test_bit(endp, f->endpoints))
 
2023					break;
 
2024			}
2025			if (&f->list == &cdev->config->functions)
2026				f = NULL;
2027			break;
2028		}
2029try_fun_setup:
2030		if (f && f->setup)
2031			value = f->setup(f, ctrl);
2032		else {
2033			struct usb_configuration	*c;
2034
2035			c = cdev->config;
2036			if (!c)
2037				goto done;
2038
2039			/* try current config's setup */
2040			if (c->setup) {
2041				value = c->setup(c, ctrl);
2042				goto done;
2043			}
2044
2045			/* try the only function in the current config */
2046			if (!list_is_singular(&c->functions))
2047				goto done;
2048			f = list_first_entry(&c->functions, struct usb_function,
2049					     list);
2050			if (f->setup)
2051				value = f->setup(f, ctrl);
2052		}
2053
2054		goto done;
2055	}
2056
2057check_value:
2058	/* respond with data transfer before status phase? */
2059	if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
2060		req->length = value;
2061		req->context = cdev;
2062		req->zero = value < w_length;
2063		value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2064		if (value < 0) {
2065			DBG(cdev, "ep_queue --> %d\n", value);
2066			req->status = 0;
2067			composite_setup_complete(gadget->ep0, req);
2068		}
2069	} else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
2070		WARN(cdev,
2071			"%s: Delayed status not supported for w_length != 0",
2072			__func__);
2073	}
2074
2075done:
2076	/* device either stalls (value < 0) or reports success */
2077	return value;
2078}
2079
2080static void __composite_disconnect(struct usb_gadget *gadget)
2081{
2082	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2083	unsigned long			flags;
2084
2085	/* REVISIT:  should we have config and device level
2086	 * disconnect callbacks?
2087	 */
2088	spin_lock_irqsave(&cdev->lock, flags);
2089	cdev->suspended = 0;
2090	if (cdev->config)
2091		reset_config(cdev);
2092	if (cdev->driver->disconnect)
2093		cdev->driver->disconnect(cdev);
2094	spin_unlock_irqrestore(&cdev->lock, flags);
2095}
2096
2097void composite_disconnect(struct usb_gadget *gadget)
2098{
2099	usb_gadget_vbus_draw(gadget, 0);
2100	__composite_disconnect(gadget);
2101}
2102
2103void composite_reset(struct usb_gadget *gadget)
2104{
2105	/*
2106	 * Section 1.4.13 Standard Downstream Port of the USB battery charging
2107	 * specification v1.2 states that a device connected on a SDP shall only
2108	 * draw at max 100mA while in a connected, but unconfigured state.
2109	 */
2110	usb_gadget_vbus_draw(gadget, 100);
2111	__composite_disconnect(gadget);
2112}
2113
2114/*-------------------------------------------------------------------------*/
2115
2116static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2117			      char *buf)
2118{
2119	struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2120	struct usb_composite_dev *cdev = get_gadget_data(gadget);
2121
2122	return sprintf(buf, "%d\n", cdev->suspended);
2123}
2124static DEVICE_ATTR_RO(suspended);
2125
2126static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2127{
2128	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2129	struct usb_gadget_strings	*gstr = cdev->driver->strings[0];
2130	struct usb_string		*dev_str = gstr->strings;
2131
2132	/* composite_disconnect() must already have been called
2133	 * by the underlying peripheral controller driver!
2134	 * so there's no i/o concurrency that could affect the
2135	 * state protected by cdev->lock.
2136	 */
2137	WARN_ON(cdev->config);
2138
2139	while (!list_empty(&cdev->configs)) {
2140		struct usb_configuration	*c;
2141		c = list_first_entry(&cdev->configs,
2142				struct usb_configuration, list);
2143		remove_config(cdev, c);
2144	}
2145	if (cdev->driver->unbind && unbind_driver)
2146		cdev->driver->unbind(cdev);
2147
2148	composite_dev_cleanup(cdev);
2149
2150	if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
2151		dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
2152
2153	kfree(cdev->def_manufacturer);
2154	kfree(cdev);
2155	set_gadget_data(gadget, NULL);
2156}
2157
2158static void composite_unbind(struct usb_gadget *gadget)
2159{
2160	__composite_unbind(gadget, true);
2161}
2162
2163static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2164		const struct usb_device_descriptor *old)
2165{
2166	__le16 idVendor;
2167	__le16 idProduct;
2168	__le16 bcdDevice;
2169	u8 iSerialNumber;
2170	u8 iManufacturer;
2171	u8 iProduct;
2172
2173	/*
2174	 * these variables may have been set in
2175	 * usb_composite_overwrite_options()
2176	 */
2177	idVendor = new->idVendor;
2178	idProduct = new->idProduct;
2179	bcdDevice = new->bcdDevice;
2180	iSerialNumber = new->iSerialNumber;
2181	iManufacturer = new->iManufacturer;
2182	iProduct = new->iProduct;
2183
2184	*new = *old;
2185	if (idVendor)
2186		new->idVendor = idVendor;
2187	if (idProduct)
2188		new->idProduct = idProduct;
2189	if (bcdDevice)
2190		new->bcdDevice = bcdDevice;
2191	else
2192		new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2193	if (iSerialNumber)
2194		new->iSerialNumber = iSerialNumber;
2195	if (iManufacturer)
2196		new->iManufacturer = iManufacturer;
2197	if (iProduct)
2198		new->iProduct = iProduct;
2199}
2200
2201int composite_dev_prepare(struct usb_composite_driver *composite,
2202		struct usb_composite_dev *cdev)
2203{
2204	struct usb_gadget *gadget = cdev->gadget;
2205	int ret = -ENOMEM;
2206
2207	/* preallocate control response and buffer */
2208	cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2209	if (!cdev->req)
2210		return -ENOMEM;
2211
2212	cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2213	if (!cdev->req->buf)
2214		goto fail;
2215
2216	ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2217	if (ret)
2218		goto fail_dev;
2219
2220	cdev->req->complete = composite_setup_complete;
2221	cdev->req->context = cdev;
2222	gadget->ep0->driver_data = cdev;
2223
2224	cdev->driver = composite;
2225
2226	/*
2227	 * As per USB compliance update, a device that is actively drawing
2228	 * more than 100mA from USB must report itself as bus-powered in
2229	 * the GetStatus(DEVICE) call.
2230	 */
2231	if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2232		usb_gadget_set_selfpowered(gadget);
2233
2234	/* interface and string IDs start at zero via kzalloc.
2235	 * we force endpoints to start unassigned; few controller
2236	 * drivers will zero ep->driver_data.
2237	 */
2238	usb_ep_autoconfig_reset(gadget);
2239	return 0;
2240fail_dev:
2241	kfree(cdev->req->buf);
2242fail:
2243	usb_ep_free_request(gadget->ep0, cdev->req);
2244	cdev->req = NULL;
2245	return ret;
2246}
2247
2248int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2249				  struct usb_ep *ep0)
2250{
2251	int ret = 0;
2252
2253	cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2254	if (!cdev->os_desc_req) {
2255		ret = -ENOMEM;
2256		goto end;
2257	}
2258
2259	cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2260					 GFP_KERNEL);
2261	if (!cdev->os_desc_req->buf) {
2262		ret = -ENOMEM;
2263		usb_ep_free_request(ep0, cdev->os_desc_req);
2264		goto end;
2265	}
2266	cdev->os_desc_req->context = cdev;
2267	cdev->os_desc_req->complete = composite_setup_complete;
2268end:
2269	return ret;
2270}
2271
2272void composite_dev_cleanup(struct usb_composite_dev *cdev)
2273{
2274	struct usb_gadget_string_container *uc, *tmp;
2275	struct usb_ep			   *ep, *tmp_ep;
2276
2277	list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2278		list_del(&uc->list);
2279		kfree(uc);
2280	}
2281	if (cdev->os_desc_req) {
2282		if (cdev->os_desc_pending)
2283			usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2284
2285		kfree(cdev->os_desc_req->buf);
2286		cdev->os_desc_req->buf = NULL;
2287		usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2288		cdev->os_desc_req = NULL;
2289	}
2290	if (cdev->req) {
2291		if (cdev->setup_pending)
2292			usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2293
2294		kfree(cdev->req->buf);
2295		cdev->req->buf = NULL;
2296		usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2297		cdev->req = NULL;
2298	}
2299	cdev->next_string_id = 0;
2300	device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2301
2302	/*
2303	 * Some UDC backends have a dynamic EP allocation scheme.
2304	 *
2305	 * In that case, the dispose() callback is used to notify the
2306	 * backend that the EPs are no longer in use.
2307	 *
2308	 * Note: The UDC backend can remove the EP from the ep_list as
2309	 *	 a result, so we need to use the _safe list iterator.
2310	 */
2311	list_for_each_entry_safe(ep, tmp_ep,
2312				 &cdev->gadget->ep_list, ep_list) {
2313		if (ep->ops->dispose)
2314			ep->ops->dispose(ep);
2315	}
2316}
2317
2318static int composite_bind(struct usb_gadget *gadget,
2319		struct usb_gadget_driver *gdriver)
2320{
2321	struct usb_composite_dev	*cdev;
2322	struct usb_composite_driver	*composite = to_cdriver(gdriver);
2323	int				status = -ENOMEM;
2324
2325	cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2326	if (!cdev)
2327		return status;
2328
2329	spin_lock_init(&cdev->lock);
2330	cdev->gadget = gadget;
2331	set_gadget_data(gadget, cdev);
2332	INIT_LIST_HEAD(&cdev->configs);
2333	INIT_LIST_HEAD(&cdev->gstrings);
2334
2335	status = composite_dev_prepare(composite, cdev);
2336	if (status)
2337		goto fail;
2338
2339	/* composite gadget needs to assign strings for whole device (like
2340	 * serial number), register function drivers, potentially update
2341	 * power state and consumption, etc
2342	 */
2343	status = composite->bind(cdev);
2344	if (status < 0)
2345		goto fail;
2346
2347	if (cdev->use_os_string) {
2348		status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2349		if (status)
2350			goto fail;
2351	}
2352
2353	update_unchanged_dev_desc(&cdev->desc, composite->dev);
2354
2355	/* has userspace failed to provide a serial number? */
2356	if (composite->needs_serial && !cdev->desc.iSerialNumber)
2357		WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2358
2359	INFO(cdev, "%s ready\n", composite->name);
2360	return 0;
2361
2362fail:
2363	__composite_unbind(gadget, false);
2364	return status;
2365}
2366
2367/*-------------------------------------------------------------------------*/
2368
2369void composite_suspend(struct usb_gadget *gadget)
2370{
2371	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2372	struct usb_function		*f;
2373
2374	/* REVISIT:  should we have config level
2375	 * suspend/resume callbacks?
2376	 */
2377	DBG(cdev, "suspend\n");
2378	if (cdev->config) {
2379		list_for_each_entry(f, &cdev->config->functions, list) {
2380			if (f->suspend)
2381				f->suspend(f);
2382		}
2383	}
2384	if (cdev->driver->suspend)
2385		cdev->driver->suspend(cdev);
2386
2387	cdev->suspended = 1;
2388
2389	usb_gadget_set_selfpowered(gadget);
 
 
 
2390	usb_gadget_vbus_draw(gadget, 2);
2391}
2392
2393void composite_resume(struct usb_gadget *gadget)
2394{
2395	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2396	struct usb_function		*f;
2397	unsigned			maxpower;
2398
2399	/* REVISIT:  should we have config level
2400	 * suspend/resume callbacks?
2401	 */
2402	DBG(cdev, "resume\n");
2403	if (cdev->driver->resume)
2404		cdev->driver->resume(cdev);
2405	if (cdev->config) {
2406		list_for_each_entry(f, &cdev->config->functions, list) {
2407			if (f->resume)
 
 
 
 
 
2408				f->resume(f);
2409		}
2410
2411		maxpower = cdev->config->MaxPower ?
2412			cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
2413		if (gadget->speed < USB_SPEED_SUPER)
2414			maxpower = min(maxpower, 500U);
2415		else
2416			maxpower = min(maxpower, 900U);
2417
2418		if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
 
2419			usb_gadget_clear_selfpowered(gadget);
 
 
2420
2421		usb_gadget_vbus_draw(gadget, maxpower);
 
 
 
 
2422	}
2423
2424	cdev->suspended = 0;
2425}
2426
2427/*-------------------------------------------------------------------------*/
2428
2429static const struct usb_gadget_driver composite_driver_template = {
2430	.bind		= composite_bind,
2431	.unbind		= composite_unbind,
2432
2433	.setup		= composite_setup,
2434	.reset		= composite_reset,
2435	.disconnect	= composite_disconnect,
2436
2437	.suspend	= composite_suspend,
2438	.resume		= composite_resume,
2439
2440	.driver	= {
2441		.owner		= THIS_MODULE,
2442	},
2443};
2444
2445/**
2446 * usb_composite_probe() - register a composite driver
2447 * @driver: the driver to register
2448 *
2449 * Context: single threaded during gadget setup
2450 *
2451 * This function is used to register drivers using the composite driver
2452 * framework.  The return value is zero, or a negative errno value.
2453 * Those values normally come from the driver's @bind method, which does
2454 * all the work of setting up the driver to match the hardware.
2455 *
2456 * On successful return, the gadget is ready to respond to requests from
2457 * the host, unless one of its components invokes usb_gadget_disconnect()
2458 * while it was binding.  That would usually be done in order to wait for
2459 * some userspace participation.
2460 */
2461int usb_composite_probe(struct usb_composite_driver *driver)
2462{
2463	struct usb_gadget_driver *gadget_driver;
2464
2465	if (!driver || !driver->dev || !driver->bind)
2466		return -EINVAL;
2467
2468	if (!driver->name)
2469		driver->name = "composite";
2470
2471	driver->gadget_driver = composite_driver_template;
2472	gadget_driver = &driver->gadget_driver;
2473
2474	gadget_driver->function =  (char *) driver->name;
2475	gadget_driver->driver.name = driver->name;
2476	gadget_driver->max_speed = driver->max_speed;
2477
2478	return usb_gadget_probe_driver(gadget_driver);
2479}
2480EXPORT_SYMBOL_GPL(usb_composite_probe);
2481
2482/**
2483 * usb_composite_unregister() - unregister a composite driver
2484 * @driver: the driver to unregister
2485 *
2486 * This function is used to unregister drivers using the composite
2487 * driver framework.
2488 */
2489void usb_composite_unregister(struct usb_composite_driver *driver)
2490{
2491	usb_gadget_unregister_driver(&driver->gadget_driver);
2492}
2493EXPORT_SYMBOL_GPL(usb_composite_unregister);
2494
2495/**
2496 * usb_composite_setup_continue() - Continue with the control transfer
2497 * @cdev: the composite device who's control transfer was kept waiting
2498 *
2499 * This function must be called by the USB function driver to continue
2500 * with the control transfer's data/status stage in case it had requested to
2501 * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2502 * can request the composite framework to delay the setup request's data/status
2503 * stages by returning USB_GADGET_DELAYED_STATUS.
2504 */
2505void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2506{
2507	int			value;
2508	struct usb_request	*req = cdev->req;
2509	unsigned long		flags;
2510
2511	DBG(cdev, "%s\n", __func__);
2512	spin_lock_irqsave(&cdev->lock, flags);
2513
2514	if (cdev->delayed_status == 0) {
2515		WARN(cdev, "%s: Unexpected call\n", __func__);
2516
2517	} else if (--cdev->delayed_status == 0) {
2518		DBG(cdev, "%s: Completing delayed status\n", __func__);
2519		req->length = 0;
2520		req->context = cdev;
2521		value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2522		if (value < 0) {
2523			DBG(cdev, "ep_queue --> %d\n", value);
2524			req->status = 0;
2525			composite_setup_complete(cdev->gadget->ep0, req);
2526		}
2527	}
2528
2529	spin_unlock_irqrestore(&cdev->lock, flags);
2530}
2531EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2532
2533static char *composite_default_mfr(struct usb_gadget *gadget)
2534{
2535	return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2536			 init_utsname()->release, gadget->name);
2537}
2538
2539void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2540		struct usb_composite_overwrite *covr)
2541{
2542	struct usb_device_descriptor	*desc = &cdev->desc;
2543	struct usb_gadget_strings	*gstr = cdev->driver->strings[0];
2544	struct usb_string		*dev_str = gstr->strings;
2545
2546	if (covr->idVendor)
2547		desc->idVendor = cpu_to_le16(covr->idVendor);
2548
2549	if (covr->idProduct)
2550		desc->idProduct = cpu_to_le16(covr->idProduct);
2551
2552	if (covr->bcdDevice)
2553		desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2554
2555	if (covr->serial_number) {
2556		desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2557		dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2558	}
2559	if (covr->manufacturer) {
2560		desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2561		dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2562
2563	} else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2564		desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2565		cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2566		dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2567	}
2568
2569	if (covr->product) {
2570		desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2571		dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2572	}
2573}
2574EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2575
 
2576MODULE_LICENSE("GPL");
2577MODULE_AUTHOR("David Brownell");