Linux Audio

Check our new training course

Real-Time Linux with PREEMPT_RT training

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