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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * drivers/usb/core/sysfs.c
   4 *
   5 * (C) Copyright 2002 David Brownell
   6 * (C) Copyright 2002,2004 Greg Kroah-Hartman
   7 * (C) Copyright 2002,2004 IBM Corp.
   8 *
   9 * All of the sysfs file attributes for usb devices and interfaces.
  10 *
  11 * Released under the GPLv2 only.
  12 */
  13
  14
  15#include <linux/kernel.h>
  16#include <linux/kstrtox.h>
  17#include <linux/string.h>
  18#include <linux/usb.h>
  19#include <linux/usb/hcd.h>
  20#include <linux/usb/quirks.h>
  21#include <linux/of.h>
  22#include "usb.h"
  23
  24/* Active configuration fields */
  25#define usb_actconfig_show(field, format_string)			\
  26static ssize_t field##_show(struct device *dev,				\
  27			    struct device_attribute *attr, char *buf)	\
  28{									\
  29	struct usb_device *udev;					\
  30	struct usb_host_config *actconfig;				\
  31	ssize_t rc;							\
  32									\
  33	udev = to_usb_device(dev);					\
  34	rc = usb_lock_device_interruptible(udev);			\
  35	if (rc < 0)							\
  36		return -EINTR;						\
  37	actconfig = udev->actconfig;					\
  38	if (actconfig)							\
  39		rc = sysfs_emit(buf, format_string,			\
  40				actconfig->desc.field);			\
  41	usb_unlock_device(udev);					\
  42	return rc;							\
  43}									\
  44
  45#define usb_actconfig_attr(field, format_string)		\
  46	usb_actconfig_show(field, format_string)		\
  47	static DEVICE_ATTR_RO(field)
  48
  49usb_actconfig_attr(bNumInterfaces, "%2d\n");
  50usb_actconfig_attr(bmAttributes, "%2x\n");
  51
  52static ssize_t bMaxPower_show(struct device *dev,
  53		struct device_attribute *attr, char *buf)
  54{
  55	struct usb_device *udev;
  56	struct usb_host_config *actconfig;
  57	ssize_t rc;
  58
  59	udev = to_usb_device(dev);
  60	rc = usb_lock_device_interruptible(udev);
  61	if (rc < 0)
  62		return -EINTR;
  63	actconfig = udev->actconfig;
  64	if (actconfig)
  65		rc = sysfs_emit(buf, "%dmA\n", usb_get_max_power(udev, actconfig));
  66	usb_unlock_device(udev);
  67	return rc;
  68}
  69static DEVICE_ATTR_RO(bMaxPower);
  70
  71static ssize_t configuration_show(struct device *dev,
  72		struct device_attribute *attr, char *buf)
  73{
  74	struct usb_device *udev;
  75	struct usb_host_config *actconfig;
  76	ssize_t rc;
  77
  78	udev = to_usb_device(dev);
  79	rc = usb_lock_device_interruptible(udev);
  80	if (rc < 0)
  81		return -EINTR;
  82	actconfig = udev->actconfig;
  83	if (actconfig && actconfig->string)
  84		rc = sysfs_emit(buf, "%s\n", actconfig->string);
  85	usb_unlock_device(udev);
  86	return rc;
  87}
  88static DEVICE_ATTR_RO(configuration);
  89
  90/* configuration value is always present, and r/w */
  91usb_actconfig_show(bConfigurationValue, "%u\n");
  92
  93static ssize_t bConfigurationValue_store(struct device *dev,
  94					 struct device_attribute *attr,
  95					 const char *buf, size_t count)
  96{
  97	struct usb_device	*udev = to_usb_device(dev);
  98	int			config, value, rc;
  99
 100	if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
 101		return -EINVAL;
 102	rc = usb_lock_device_interruptible(udev);
 103	if (rc < 0)
 104		return -EINTR;
 105	value = usb_set_configuration(udev, config);
 106	usb_unlock_device(udev);
 107	return (value < 0) ? value : count;
 108}
 109static DEVICE_ATTR_IGNORE_LOCKDEP(bConfigurationValue, S_IRUGO | S_IWUSR,
 110		bConfigurationValue_show, bConfigurationValue_store);
 111
 112#ifdef CONFIG_OF
 113static ssize_t devspec_show(struct device *dev, struct device_attribute *attr,
 114			    char *buf)
 115{
 116	struct device_node *of_node = dev->of_node;
 117
 118	return sysfs_emit(buf, "%pOF\n", of_node);
 119}
 120static DEVICE_ATTR_RO(devspec);
 121#endif
 122
 123/* String fields */
 124#define usb_string_attr(name)						\
 125static ssize_t  name##_show(struct device *dev,				\
 126		struct device_attribute *attr, char *buf)		\
 127{									\
 128	struct usb_device *udev;					\
 129	int retval;							\
 130									\
 131	udev = to_usb_device(dev);					\
 132	retval = usb_lock_device_interruptible(udev);			\
 133	if (retval < 0)							\
 134		return -EINTR;						\
 135	retval = sysfs_emit(buf, "%s\n", udev->name);			\
 136	usb_unlock_device(udev);					\
 137	return retval;							\
 138}									\
 139static DEVICE_ATTR_RO(name)
 140
 141usb_string_attr(product);
 142usb_string_attr(manufacturer);
 143usb_string_attr(serial);
 144
 145static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
 146			  char *buf)
 147{
 148	struct usb_device *udev;
 149	char *speed;
 150
 151	udev = to_usb_device(dev);
 152
 153	switch (udev->speed) {
 154	case USB_SPEED_LOW:
 155		speed = "1.5";
 156		break;
 157	case USB_SPEED_UNKNOWN:
 158	case USB_SPEED_FULL:
 159		speed = "12";
 160		break;
 161	case USB_SPEED_HIGH:
 162		speed = "480";
 163		break;
 
 
 
 164	case USB_SPEED_SUPER:
 165		speed = "5000";
 166		break;
 167	case USB_SPEED_SUPER_PLUS:
 168		if (udev->ssp_rate == USB_SSP_GEN_2x2)
 169			speed = "20000";
 170		else
 171			speed = "10000";
 172		break;
 173	default:
 174		speed = "unknown";
 175	}
 176	return sysfs_emit(buf, "%s\n", speed);
 177}
 178static DEVICE_ATTR_RO(speed);
 179
 180static ssize_t rx_lanes_show(struct device *dev, struct device_attribute *attr,
 181			  char *buf)
 182{
 183	struct usb_device *udev;
 184
 185	udev = to_usb_device(dev);
 186	return sysfs_emit(buf, "%d\n", udev->rx_lanes);
 187}
 188static DEVICE_ATTR_RO(rx_lanes);
 189
 190static ssize_t tx_lanes_show(struct device *dev, struct device_attribute *attr,
 191			  char *buf)
 192{
 193	struct usb_device *udev;
 194
 195	udev = to_usb_device(dev);
 196	return sysfs_emit(buf, "%d\n", udev->tx_lanes);
 197}
 198static DEVICE_ATTR_RO(tx_lanes);
 199
 200static ssize_t busnum_show(struct device *dev, struct device_attribute *attr,
 201			   char *buf)
 202{
 203	struct usb_device *udev;
 204
 205	udev = to_usb_device(dev);
 206	return sysfs_emit(buf, "%d\n", udev->bus->busnum);
 207}
 208static DEVICE_ATTR_RO(busnum);
 209
 210static ssize_t devnum_show(struct device *dev, struct device_attribute *attr,
 211			   char *buf)
 212{
 213	struct usb_device *udev;
 214
 215	udev = to_usb_device(dev);
 216	return sysfs_emit(buf, "%d\n", udev->devnum);
 217}
 218static DEVICE_ATTR_RO(devnum);
 219
 220static ssize_t devpath_show(struct device *dev, struct device_attribute *attr,
 221			    char *buf)
 222{
 223	struct usb_device *udev;
 224
 225	udev = to_usb_device(dev);
 226	return sysfs_emit(buf, "%s\n", udev->devpath);
 227}
 228static DEVICE_ATTR_RO(devpath);
 229
 230static ssize_t version_show(struct device *dev, struct device_attribute *attr,
 231			    char *buf)
 232{
 233	struct usb_device *udev;
 234	u16 bcdUSB;
 235
 236	udev = to_usb_device(dev);
 237	bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
 238	return sysfs_emit(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
 239}
 240static DEVICE_ATTR_RO(version);
 241
 242static ssize_t maxchild_show(struct device *dev, struct device_attribute *attr,
 243			     char *buf)
 244{
 245	struct usb_device *udev;
 246
 247	udev = to_usb_device(dev);
 248	return sysfs_emit(buf, "%d\n", udev->maxchild);
 249}
 250static DEVICE_ATTR_RO(maxchild);
 251
 252static ssize_t quirks_show(struct device *dev, struct device_attribute *attr,
 253			   char *buf)
 254{
 255	struct usb_device *udev;
 256
 257	udev = to_usb_device(dev);
 258	return sysfs_emit(buf, "0x%x\n", udev->quirks);
 259}
 260static DEVICE_ATTR_RO(quirks);
 261
 262static ssize_t avoid_reset_quirk_show(struct device *dev,
 263				      struct device_attribute *attr, char *buf)
 264{
 265	struct usb_device *udev;
 266
 267	udev = to_usb_device(dev);
 268	return sysfs_emit(buf, "%d\n", !!(udev->quirks & USB_QUIRK_RESET));
 269}
 270
 271static ssize_t avoid_reset_quirk_store(struct device *dev,
 272				      struct device_attribute *attr,
 273				      const char *buf, size_t count)
 274{
 275	struct usb_device	*udev = to_usb_device(dev);
 276	bool			val;
 277	int			rc;
 278
 279	if (kstrtobool(buf, &val) != 0)
 280		return -EINVAL;
 281	rc = usb_lock_device_interruptible(udev);
 282	if (rc < 0)
 283		return -EINTR;
 284	if (val)
 285		udev->quirks |= USB_QUIRK_RESET;
 286	else
 287		udev->quirks &= ~USB_QUIRK_RESET;
 288	usb_unlock_device(udev);
 289	return count;
 290}
 291static DEVICE_ATTR_RW(avoid_reset_quirk);
 292
 293static ssize_t urbnum_show(struct device *dev, struct device_attribute *attr,
 294			   char *buf)
 295{
 296	struct usb_device *udev;
 297
 298	udev = to_usb_device(dev);
 299	return sysfs_emit(buf, "%d\n", atomic_read(&udev->urbnum));
 300}
 301static DEVICE_ATTR_RO(urbnum);
 302
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 303static ssize_t ltm_capable_show(struct device *dev,
 304				struct device_attribute *attr, char *buf)
 305{
 306	if (usb_device_supports_ltm(to_usb_device(dev)))
 307		return sysfs_emit(buf, "%s\n", "yes");
 308	return sysfs_emit(buf, "%s\n", "no");
 309}
 310static DEVICE_ATTR_RO(ltm_capable);
 311
 312#ifdef	CONFIG_PM
 313
 314static ssize_t persist_show(struct device *dev, struct device_attribute *attr,
 315			    char *buf)
 316{
 317	struct usb_device *udev = to_usb_device(dev);
 318
 319	return sysfs_emit(buf, "%d\n", udev->persist_enabled);
 320}
 321
 322static ssize_t persist_store(struct device *dev, struct device_attribute *attr,
 323			     const char *buf, size_t count)
 324{
 325	struct usb_device *udev = to_usb_device(dev);
 326	bool value;
 327	int rc;
 328
 329	/* Hubs are always enabled for USB_PERSIST */
 330	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
 331		return -EPERM;
 332
 333	if (kstrtobool(buf, &value) != 0)
 334		return -EINVAL;
 335
 336	rc = usb_lock_device_interruptible(udev);
 337	if (rc < 0)
 338		return -EINTR;
 339	udev->persist_enabled = !!value;
 340	usb_unlock_device(udev);
 341	return count;
 342}
 343static DEVICE_ATTR_RW(persist);
 344
 345static int add_persist_attributes(struct device *dev)
 346{
 347	int rc = 0;
 348
 349	if (is_usb_device(dev)) {
 350		struct usb_device *udev = to_usb_device(dev);
 351
 352		/* Hubs are automatically enabled for USB_PERSIST,
 353		 * no point in creating the attribute file.
 354		 */
 355		if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
 356			rc = sysfs_add_file_to_group(&dev->kobj,
 357					&dev_attr_persist.attr,
 358					power_group_name);
 359	}
 360	return rc;
 361}
 362
 363static void remove_persist_attributes(struct device *dev)
 364{
 365	sysfs_remove_file_from_group(&dev->kobj,
 366			&dev_attr_persist.attr,
 367			power_group_name);
 368}
 369
 370static ssize_t connected_duration_show(struct device *dev,
 371				       struct device_attribute *attr, char *buf)
 372{
 373	struct usb_device *udev = to_usb_device(dev);
 374
 375	return sysfs_emit(buf, "%u\n",
 376			jiffies_to_msecs(jiffies - udev->connect_time));
 377}
 378static DEVICE_ATTR_RO(connected_duration);
 379
 380/*
 381 * If the device is resumed, the last time the device was suspended has
 382 * been pre-subtracted from active_duration.  We add the current time to
 383 * get the duration that the device was actually active.
 384 *
 385 * If the device is suspended, the active_duration is up-to-date.
 386 */
 387static ssize_t active_duration_show(struct device *dev,
 388				    struct device_attribute *attr, char *buf)
 389{
 390	struct usb_device *udev = to_usb_device(dev);
 391	int duration;
 392
 393	if (udev->state != USB_STATE_SUSPENDED)
 394		duration = jiffies_to_msecs(jiffies + udev->active_duration);
 395	else
 396		duration = jiffies_to_msecs(udev->active_duration);
 397	return sysfs_emit(buf, "%u\n", duration);
 398}
 399static DEVICE_ATTR_RO(active_duration);
 400
 401static ssize_t autosuspend_show(struct device *dev,
 402				struct device_attribute *attr, char *buf)
 403{
 404	return sysfs_emit(buf, "%d\n", dev->power.autosuspend_delay / 1000);
 405}
 406
 407static ssize_t autosuspend_store(struct device *dev,
 408				 struct device_attribute *attr, const char *buf,
 409				 size_t count)
 410{
 411	int value;
 412
 413	if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/1000 ||
 414			value <= -INT_MAX/1000)
 415		return -EINVAL;
 416
 417	pm_runtime_set_autosuspend_delay(dev, value * 1000);
 418	return count;
 419}
 420static DEVICE_ATTR_RW(autosuspend);
 421
 422static const char on_string[] = "on";
 423static const char auto_string[] = "auto";
 424
 425static void warn_level(void)
 426{
 427	static int level_warned;
 428
 429	if (!level_warned) {
 430		level_warned = 1;
 431		printk(KERN_WARNING "WARNING! power/level is deprecated; "
 432				"use power/control instead\n");
 433	}
 434}
 435
 436static ssize_t level_show(struct device *dev, struct device_attribute *attr,
 437			  char *buf)
 438{
 439	struct usb_device *udev = to_usb_device(dev);
 440	const char *p = auto_string;
 441
 442	warn_level();
 443	if (udev->state != USB_STATE_SUSPENDED && !udev->dev.power.runtime_auto)
 444		p = on_string;
 445	return sysfs_emit(buf, "%s\n", p);
 446}
 447
 448static ssize_t level_store(struct device *dev, struct device_attribute *attr,
 449			   const char *buf, size_t count)
 450{
 451	struct usb_device *udev = to_usb_device(dev);
 452	int len = count;
 453	char *cp;
 454	int rc = count;
 455	int rv;
 456
 457	warn_level();
 458	cp = memchr(buf, '\n', count);
 459	if (cp)
 460		len = cp - buf;
 461
 462	rv = usb_lock_device_interruptible(udev);
 463	if (rv < 0)
 464		return -EINTR;
 465
 466	if (len == sizeof on_string - 1 &&
 467			strncmp(buf, on_string, len) == 0)
 468		usb_disable_autosuspend(udev);
 469
 470	else if (len == sizeof auto_string - 1 &&
 471			strncmp(buf, auto_string, len) == 0)
 472		usb_enable_autosuspend(udev);
 473
 474	else
 475		rc = -EINVAL;
 476
 477	usb_unlock_device(udev);
 478	return rc;
 479}
 480static DEVICE_ATTR_RW(level);
 481
 482static ssize_t usb2_hardware_lpm_show(struct device *dev,
 483				      struct device_attribute *attr, char *buf)
 484{
 485	struct usb_device *udev = to_usb_device(dev);
 486	const char *p;
 487
 488	if (udev->usb2_hw_lpm_allowed == 1)
 489		p = "enabled";
 490	else
 491		p = "disabled";
 492
 493	return sysfs_emit(buf, "%s\n", p);
 494}
 495
 496static ssize_t usb2_hardware_lpm_store(struct device *dev,
 497				       struct device_attribute *attr,
 498				       const char *buf, size_t count)
 499{
 500	struct usb_device *udev = to_usb_device(dev);
 501	bool value;
 502	int ret;
 503
 504	ret = usb_lock_device_interruptible(udev);
 505	if (ret < 0)
 506		return -EINTR;
 507
 508	ret = kstrtobool(buf, &value);
 509
 510	if (!ret) {
 511		udev->usb2_hw_lpm_allowed = value;
 512		if (value)
 513			ret = usb_enable_usb2_hardware_lpm(udev);
 514		else
 515			ret = usb_disable_usb2_hardware_lpm(udev);
 516	}
 517
 518	usb_unlock_device(udev);
 519
 520	if (!ret)
 521		return count;
 522
 523	return ret;
 524}
 525static DEVICE_ATTR_RW(usb2_hardware_lpm);
 526
 527static ssize_t usb2_lpm_l1_timeout_show(struct device *dev,
 528					struct device_attribute *attr,
 529					char *buf)
 530{
 531	struct usb_device *udev = to_usb_device(dev);
 532	return sysfs_emit(buf, "%d\n", udev->l1_params.timeout);
 533}
 534
 535static ssize_t usb2_lpm_l1_timeout_store(struct device *dev,
 536					 struct device_attribute *attr,
 537					 const char *buf, size_t count)
 538{
 539	struct usb_device *udev = to_usb_device(dev);
 540	u16 timeout;
 541
 542	if (kstrtou16(buf, 0, &timeout))
 543		return -EINVAL;
 544
 545	udev->l1_params.timeout = timeout;
 546
 547	return count;
 548}
 549static DEVICE_ATTR_RW(usb2_lpm_l1_timeout);
 550
 551static ssize_t usb2_lpm_besl_show(struct device *dev,
 552				  struct device_attribute *attr, char *buf)
 553{
 554	struct usb_device *udev = to_usb_device(dev);
 555	return sysfs_emit(buf, "%d\n", udev->l1_params.besl);
 556}
 557
 558static ssize_t usb2_lpm_besl_store(struct device *dev,
 559				   struct device_attribute *attr,
 560				   const char *buf, size_t count)
 561{
 562	struct usb_device *udev = to_usb_device(dev);
 563	u8 besl;
 564
 565	if (kstrtou8(buf, 0, &besl) || besl > 15)
 566		return -EINVAL;
 567
 568	udev->l1_params.besl = besl;
 569
 570	return count;
 571}
 572static DEVICE_ATTR_RW(usb2_lpm_besl);
 573
 574static ssize_t usb3_hardware_lpm_u1_show(struct device *dev,
 575				      struct device_attribute *attr, char *buf)
 576{
 577	struct usb_device *udev = to_usb_device(dev);
 578	const char *p;
 579	int rc;
 580
 581	rc = usb_lock_device_interruptible(udev);
 582	if (rc < 0)
 583		return -EINTR;
 584
 585	if (udev->usb3_lpm_u1_enabled)
 586		p = "enabled";
 587	else
 588		p = "disabled";
 589
 590	usb_unlock_device(udev);
 591
 592	return sysfs_emit(buf, "%s\n", p);
 593}
 594static DEVICE_ATTR_RO(usb3_hardware_lpm_u1);
 595
 596static ssize_t usb3_hardware_lpm_u2_show(struct device *dev,
 597				      struct device_attribute *attr, char *buf)
 598{
 599	struct usb_device *udev = to_usb_device(dev);
 600	const char *p;
 601	int rc;
 602
 603	rc = usb_lock_device_interruptible(udev);
 604	if (rc < 0)
 605		return -EINTR;
 606
 607	if (udev->usb3_lpm_u2_enabled)
 608		p = "enabled";
 609	else
 610		p = "disabled";
 611
 612	usb_unlock_device(udev);
 613
 614	return sysfs_emit(buf, "%s\n", p);
 615}
 616static DEVICE_ATTR_RO(usb3_hardware_lpm_u2);
 617
 618static struct attribute *usb2_hardware_lpm_attr[] = {
 619	&dev_attr_usb2_hardware_lpm.attr,
 620	&dev_attr_usb2_lpm_l1_timeout.attr,
 621	&dev_attr_usb2_lpm_besl.attr,
 622	NULL,
 623};
 624static const struct attribute_group usb2_hardware_lpm_attr_group = {
 625	.name	= power_group_name,
 626	.attrs	= usb2_hardware_lpm_attr,
 627};
 628
 629static struct attribute *usb3_hardware_lpm_attr[] = {
 630	&dev_attr_usb3_hardware_lpm_u1.attr,
 631	&dev_attr_usb3_hardware_lpm_u2.attr,
 632	NULL,
 633};
 634static const struct attribute_group usb3_hardware_lpm_attr_group = {
 635	.name	= power_group_name,
 636	.attrs	= usb3_hardware_lpm_attr,
 637};
 638
 639static struct attribute *power_attrs[] = {
 640	&dev_attr_autosuspend.attr,
 641	&dev_attr_level.attr,
 642	&dev_attr_connected_duration.attr,
 643	&dev_attr_active_duration.attr,
 644	NULL,
 645};
 646static const struct attribute_group power_attr_group = {
 647	.name	= power_group_name,
 648	.attrs	= power_attrs,
 649};
 650
 651static int add_power_attributes(struct device *dev)
 652{
 653	int rc = 0;
 654
 655	if (is_usb_device(dev)) {
 656		struct usb_device *udev = to_usb_device(dev);
 657		rc = sysfs_merge_group(&dev->kobj, &power_attr_group);
 658		if (udev->usb2_hw_lpm_capable == 1)
 659			rc = sysfs_merge_group(&dev->kobj,
 660					&usb2_hardware_lpm_attr_group);
 661		if ((udev->speed == USB_SPEED_SUPER ||
 662		     udev->speed == USB_SPEED_SUPER_PLUS) &&
 663				udev->lpm_capable == 1)
 664			rc = sysfs_merge_group(&dev->kobj,
 665					&usb3_hardware_lpm_attr_group);
 666	}
 667
 668	return rc;
 669}
 670
 671static void remove_power_attributes(struct device *dev)
 672{
 673	sysfs_unmerge_group(&dev->kobj, &usb3_hardware_lpm_attr_group);
 674	sysfs_unmerge_group(&dev->kobj, &usb2_hardware_lpm_attr_group);
 675	sysfs_unmerge_group(&dev->kobj, &power_attr_group);
 676}
 677
 678#else
 679
 680#define add_persist_attributes(dev)	0
 681#define remove_persist_attributes(dev)	do {} while (0)
 682
 683#define add_power_attributes(dev)	0
 684#define remove_power_attributes(dev)	do {} while (0)
 685
 686#endif	/* CONFIG_PM */
 687
 688
 689/* Descriptor fields */
 690#define usb_descriptor_attr_le16(field, format_string)			\
 691static ssize_t								\
 692field##_show(struct device *dev, struct device_attribute *attr,	\
 693		char *buf)						\
 694{									\
 695	struct usb_device *udev;					\
 696									\
 697	udev = to_usb_device(dev);					\
 698	return sysfs_emit(buf, format_string,				\
 699			le16_to_cpu(udev->descriptor.field));		\
 700}									\
 701static DEVICE_ATTR_RO(field)
 702
 703usb_descriptor_attr_le16(idVendor, "%04x\n");
 704usb_descriptor_attr_le16(idProduct, "%04x\n");
 705usb_descriptor_attr_le16(bcdDevice, "%04x\n");
 706
 707#define usb_descriptor_attr(field, format_string)			\
 708static ssize_t								\
 709field##_show(struct device *dev, struct device_attribute *attr,	\
 710		char *buf)						\
 711{									\
 712	struct usb_device *udev;					\
 713									\
 714	udev = to_usb_device(dev);					\
 715	return sysfs_emit(buf, format_string, udev->descriptor.field);	\
 716}									\
 717static DEVICE_ATTR_RO(field)
 718
 719usb_descriptor_attr(bDeviceClass, "%02x\n");
 720usb_descriptor_attr(bDeviceSubClass, "%02x\n");
 721usb_descriptor_attr(bDeviceProtocol, "%02x\n");
 722usb_descriptor_attr(bNumConfigurations, "%d\n");
 723usb_descriptor_attr(bMaxPacketSize0, "%d\n");
 724
 725
 726/* show if the device is authorized (1) or not (0) */
 727static ssize_t authorized_show(struct device *dev,
 728			       struct device_attribute *attr, char *buf)
 729{
 730	struct usb_device *usb_dev = to_usb_device(dev);
 731	return sysfs_emit(buf, "%u\n", usb_dev->authorized);
 732}
 733
 734/*
 735 * Authorize a device to be used in the system
 736 *
 737 * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
 738 */
 739static ssize_t authorized_store(struct device *dev,
 740				struct device_attribute *attr, const char *buf,
 741				size_t size)
 742{
 743	ssize_t result;
 744	struct usb_device *usb_dev = to_usb_device(dev);
 745	bool val;
 746
 747	if (kstrtobool(buf, &val) != 0)
 748		result = -EINVAL;
 749	else if (val)
 750		result = usb_authorize_device(usb_dev);
 751	else
 752		result = usb_deauthorize_device(usb_dev);
 
 
 753	return result < 0 ? result : size;
 754}
 755static DEVICE_ATTR_IGNORE_LOCKDEP(authorized, S_IRUGO | S_IWUSR,
 756				  authorized_show, authorized_store);
 757
 758/* "Safely remove a device" */
 759static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
 760			    const char *buf, size_t count)
 761{
 762	struct usb_device *udev = to_usb_device(dev);
 763	int rc = 0;
 764
 765	usb_lock_device(udev);
 766	if (udev->state != USB_STATE_NOTATTACHED) {
 767
 768		/* To avoid races, first unconfigure and then remove */
 769		usb_set_configuration(udev, -1);
 770		rc = usb_remove_device(udev);
 771	}
 772	if (rc == 0)
 773		rc = count;
 774	usb_unlock_device(udev);
 775	return rc;
 776}
 777static DEVICE_ATTR_IGNORE_LOCKDEP(remove, S_IWUSR, NULL, remove_store);
 778
 779
 780static struct attribute *dev_attrs[] = {
 781	/* current configuration's attributes */
 782	&dev_attr_configuration.attr,
 783	&dev_attr_bNumInterfaces.attr,
 784	&dev_attr_bConfigurationValue.attr,
 785	&dev_attr_bmAttributes.attr,
 786	&dev_attr_bMaxPower.attr,
 787	/* device attributes */
 788	&dev_attr_urbnum.attr,
 789	&dev_attr_idVendor.attr,
 790	&dev_attr_idProduct.attr,
 791	&dev_attr_bcdDevice.attr,
 792	&dev_attr_bDeviceClass.attr,
 793	&dev_attr_bDeviceSubClass.attr,
 794	&dev_attr_bDeviceProtocol.attr,
 795	&dev_attr_bNumConfigurations.attr,
 796	&dev_attr_bMaxPacketSize0.attr,
 797	&dev_attr_speed.attr,
 798	&dev_attr_rx_lanes.attr,
 799	&dev_attr_tx_lanes.attr,
 800	&dev_attr_busnum.attr,
 801	&dev_attr_devnum.attr,
 802	&dev_attr_devpath.attr,
 803	&dev_attr_version.attr,
 804	&dev_attr_maxchild.attr,
 805	&dev_attr_quirks.attr,
 806	&dev_attr_avoid_reset_quirk.attr,
 807	&dev_attr_authorized.attr,
 808	&dev_attr_remove.attr,
 
 809	&dev_attr_ltm_capable.attr,
 810#ifdef CONFIG_OF
 811	&dev_attr_devspec.attr,
 812#endif
 813	NULL,
 814};
 815static const struct attribute_group dev_attr_grp = {
 816	.attrs = dev_attrs,
 817};
 818
 819/* When modifying this list, be sure to modify dev_string_attrs_are_visible()
 820 * accordingly.
 821 */
 822static struct attribute *dev_string_attrs[] = {
 823	&dev_attr_manufacturer.attr,
 824	&dev_attr_product.attr,
 825	&dev_attr_serial.attr,
 826	NULL
 827};
 828
 829static umode_t dev_string_attrs_are_visible(struct kobject *kobj,
 830		struct attribute *a, int n)
 831{
 832	struct device *dev = kobj_to_dev(kobj);
 833	struct usb_device *udev = to_usb_device(dev);
 834
 835	if (a == &dev_attr_manufacturer.attr) {
 836		if (udev->manufacturer == NULL)
 837			return 0;
 838	} else if (a == &dev_attr_product.attr) {
 839		if (udev->product == NULL)
 840			return 0;
 841	} else if (a == &dev_attr_serial.attr) {
 842		if (udev->serial == NULL)
 843			return 0;
 844	}
 845	return a->mode;
 846}
 847
 848static const struct attribute_group dev_string_attr_grp = {
 849	.attrs =	dev_string_attrs,
 850	.is_visible =	dev_string_attrs_are_visible,
 851};
 852
 
 
 
 
 
 
 853/* Binary descriptors */
 854
 855static ssize_t
 856descriptors_read(struct file *filp, struct kobject *kobj,
 857		struct bin_attribute *attr,
 858		char *buf, loff_t off, size_t count)
 859{
 860	struct device *dev = kobj_to_dev(kobj);
 861	struct usb_device *udev = to_usb_device(dev);
 862	size_t nleft = count;
 863	size_t srclen, n;
 864	int cfgno;
 865	void *src;
 866
 867	/* The binary attribute begins with the device descriptor.
 868	 * Following that are the raw descriptor entries for all the
 869	 * configurations (config plus subsidiary descriptors).
 870	 */
 871	for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
 872			nleft > 0; ++cfgno) {
 873		if (cfgno < 0) {
 874			src = &udev->descriptor;
 875			srclen = sizeof(struct usb_device_descriptor);
 876		} else {
 877			src = udev->rawdescriptors[cfgno];
 878			srclen = le16_to_cpu(udev->config[cfgno].desc.
 879					wTotalLength);
 880		}
 881		if (off < srclen) {
 882			n = min(nleft, srclen - (size_t) off);
 883			memcpy(buf, src + off, n);
 884			nleft -= n;
 885			buf += n;
 886			off = 0;
 887		} else {
 888			off -= srclen;
 889		}
 890	}
 891	return count - nleft;
 892}
 893static BIN_ATTR_RO(descriptors, 18 + 65535); /* dev descr + max-size raw descriptor */
 894
 895static ssize_t
 896bos_descriptors_read(struct file *filp, struct kobject *kobj,
 897		struct bin_attribute *attr,
 898		char *buf, loff_t off, size_t count)
 899{
 900	struct device *dev = kobj_to_dev(kobj);
 901	struct usb_device *udev = to_usb_device(dev);
 902	struct usb_host_bos *bos = udev->bos;
 903	struct usb_bos_descriptor *desc;
 904	size_t desclen, n = 0;
 905
 906	if (bos) {
 907		desc = bos->desc;
 908		desclen = le16_to_cpu(desc->wTotalLength);
 909		if (off < desclen) {
 910			n = min(count, desclen - (size_t) off);
 911			memcpy(buf, (void *) desc + off, n);
 912		}
 913	}
 914	return n;
 915}
 916static BIN_ATTR_RO(bos_descriptors, 65535); /* max-size BOS */
 917
 918/* When modifying this list, be sure to modify dev_bin_attrs_are_visible()
 919 * accordingly.
 920 */
 921static struct bin_attribute *dev_bin_attrs[] = {
 922	&bin_attr_descriptors,
 923	&bin_attr_bos_descriptors,
 924	NULL
 925};
 926
 927static umode_t dev_bin_attrs_are_visible(struct kobject *kobj,
 928		const struct bin_attribute *a, int n)
 929{
 930	struct device *dev = kobj_to_dev(kobj);
 931	struct usb_device *udev = to_usb_device(dev);
 932
 933	/*
 934	 * There's no need to check if the descriptors attribute should
 935	 * be visible because all devices have a device descriptor. The
 936	 * bos_descriptors attribute should be visible if and only if
 937	 * the device has a BOS, so check if it exists here.
 938	 */
 939	if (a == &bin_attr_bos_descriptors) {
 940		if (udev->bos == NULL)
 941			return 0;
 942	}
 943	return a->attr.mode;
 944}
 945
 946static const struct attribute_group dev_bin_attr_grp = {
 947	.bin_attrs =		dev_bin_attrs,
 948	.is_bin_visible =	dev_bin_attrs_are_visible,
 949};
 950
 951const struct attribute_group *usb_device_groups[] = {
 952	&dev_attr_grp,
 953	&dev_string_attr_grp,
 954	&dev_bin_attr_grp,
 955	NULL
 956};
 957
 958/*
 959 * Show & store the current value of authorized_default
 960 */
 961static ssize_t authorized_default_show(struct device *dev,
 962				       struct device_attribute *attr, char *buf)
 963{
 964	struct usb_device *rh_usb_dev = to_usb_device(dev);
 965	struct usb_bus *usb_bus = rh_usb_dev->bus;
 966	struct usb_hcd *hcd;
 967
 968	hcd = bus_to_hcd(usb_bus);
 969	return sysfs_emit(buf, "%u\n", hcd->dev_policy);
 970}
 971
 972static ssize_t authorized_default_store(struct device *dev,
 973					struct device_attribute *attr,
 974					const char *buf, size_t size)
 975{
 976	ssize_t result;
 977	unsigned int val;
 978	struct usb_device *rh_usb_dev = to_usb_device(dev);
 979	struct usb_bus *usb_bus = rh_usb_dev->bus;
 980	struct usb_hcd *hcd;
 981
 982	hcd = bus_to_hcd(usb_bus);
 983	result = sscanf(buf, "%u\n", &val);
 984	if (result == 1) {
 985		hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ?
 986			val : USB_DEVICE_AUTHORIZE_ALL;
 987		result = size;
 988	} else {
 989		result = -EINVAL;
 990	}
 991	return result;
 992}
 993static DEVICE_ATTR_RW(authorized_default);
 994
 995/*
 996 * interface_authorized_default_show - show default authorization status
 997 * for USB interfaces
 998 *
 999 * note: interface_authorized_default is the default value
1000 *       for initializing the authorized attribute of interfaces
1001 */
1002static ssize_t interface_authorized_default_show(struct device *dev,
1003		struct device_attribute *attr, char *buf)
1004{
1005	struct usb_device *usb_dev = to_usb_device(dev);
1006	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
1007
1008	return sysfs_emit(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
1009}
1010
1011/*
1012 * interface_authorized_default_store - store default authorization status
1013 * for USB interfaces
1014 *
1015 * note: interface_authorized_default is the default value
1016 *       for initializing the authorized attribute of interfaces
1017 */
1018static ssize_t interface_authorized_default_store(struct device *dev,
1019		struct device_attribute *attr, const char *buf, size_t count)
1020{
1021	struct usb_device *usb_dev = to_usb_device(dev);
1022	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
1023	int rc = count;
1024	bool val;
1025
1026	if (kstrtobool(buf, &val) != 0)
1027		return -EINVAL;
1028
1029	if (val)
1030		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
1031	else
1032		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
1033
1034	return rc;
1035}
1036static DEVICE_ATTR_RW(interface_authorized_default);
1037
1038/* Group all the USB bus attributes */
1039static struct attribute *usb_bus_attrs[] = {
1040		&dev_attr_authorized_default.attr,
1041		&dev_attr_interface_authorized_default.attr,
1042		NULL,
1043};
1044
1045static const struct attribute_group usb_bus_attr_group = {
1046	.name = NULL,	/* we want them in the same directory */
1047	.attrs = usb_bus_attrs,
1048};
1049
1050
1051static int add_default_authorized_attributes(struct device *dev)
1052{
1053	int rc = 0;
1054
1055	if (is_usb_device(dev))
1056		rc = sysfs_create_group(&dev->kobj, &usb_bus_attr_group);
1057
1058	return rc;
1059}
1060
1061static void remove_default_authorized_attributes(struct device *dev)
1062{
1063	if (is_usb_device(dev)) {
1064		sysfs_remove_group(&dev->kobj, &usb_bus_attr_group);
1065	}
1066}
1067
1068int usb_create_sysfs_dev_files(struct usb_device *udev)
1069{
1070	struct device *dev = &udev->dev;
1071	int retval;
1072
 
 
 
 
1073	retval = add_persist_attributes(dev);
1074	if (retval)
1075		goto error;
1076
1077	retval = add_power_attributes(dev);
1078	if (retval)
1079		goto error;
1080
1081	if (is_root_hub(udev)) {
1082		retval = add_default_authorized_attributes(dev);
1083		if (retval)
1084			goto error;
1085	}
1086	return retval;
1087
1088error:
1089	usb_remove_sysfs_dev_files(udev);
1090	return retval;
1091}
1092
1093void usb_remove_sysfs_dev_files(struct usb_device *udev)
1094{
1095	struct device *dev = &udev->dev;
1096
1097	if (is_root_hub(udev))
1098		remove_default_authorized_attributes(dev);
1099
1100	remove_power_attributes(dev);
1101	remove_persist_attributes(dev);
 
1102}
1103
1104/* Interface Association Descriptor fields */
1105#define usb_intf_assoc_attr(field, format_string)			\
1106static ssize_t								\
1107iad_##field##_show(struct device *dev, struct device_attribute *attr,	\
1108		char *buf)						\
1109{									\
1110	struct usb_interface *intf = to_usb_interface(dev);		\
1111									\
1112	return sysfs_emit(buf, format_string,				\
1113			intf->intf_assoc->field); 			\
1114}									\
1115static DEVICE_ATTR_RO(iad_##field)
1116
1117usb_intf_assoc_attr(bFirstInterface, "%02x\n");
1118usb_intf_assoc_attr(bInterfaceCount, "%02d\n");
1119usb_intf_assoc_attr(bFunctionClass, "%02x\n");
1120usb_intf_assoc_attr(bFunctionSubClass, "%02x\n");
1121usb_intf_assoc_attr(bFunctionProtocol, "%02x\n");
1122
1123/* Interface fields */
1124#define usb_intf_attr(field, format_string)				\
1125static ssize_t								\
1126field##_show(struct device *dev, struct device_attribute *attr,		\
1127		char *buf)						\
1128{									\
1129	struct usb_interface *intf = to_usb_interface(dev);		\
1130									\
1131	return sysfs_emit(buf, format_string,				\
1132			intf->cur_altsetting->desc.field); 		\
1133}									\
1134static DEVICE_ATTR_RO(field)
1135
1136usb_intf_attr(bInterfaceNumber, "%02x\n");
1137usb_intf_attr(bAlternateSetting, "%2d\n");
1138usb_intf_attr(bNumEndpoints, "%02x\n");
1139usb_intf_attr(bInterfaceClass, "%02x\n");
1140usb_intf_attr(bInterfaceSubClass, "%02x\n");
1141usb_intf_attr(bInterfaceProtocol, "%02x\n");
1142
1143static ssize_t interface_show(struct device *dev, struct device_attribute *attr,
1144			      char *buf)
1145{
1146	struct usb_interface *intf;
1147	char *string;
1148
1149	intf = to_usb_interface(dev);
1150	string = READ_ONCE(intf->cur_altsetting->string);
1151	if (!string)
1152		return 0;
1153	return sysfs_emit(buf, "%s\n", string);
1154}
1155static DEVICE_ATTR_RO(interface);
1156
1157static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
1158			     char *buf)
1159{
1160	struct usb_interface *intf;
1161	struct usb_device *udev;
1162	struct usb_host_interface *alt;
1163
1164	intf = to_usb_interface(dev);
1165	udev = interface_to_usbdev(intf);
1166	alt = READ_ONCE(intf->cur_altsetting);
1167
1168	return sysfs_emit(buf,
1169			"usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
1170			"ic%02Xisc%02Xip%02Xin%02X\n",
1171			le16_to_cpu(udev->descriptor.idVendor),
1172			le16_to_cpu(udev->descriptor.idProduct),
1173			le16_to_cpu(udev->descriptor.bcdDevice),
1174			udev->descriptor.bDeviceClass,
1175			udev->descriptor.bDeviceSubClass,
1176			udev->descriptor.bDeviceProtocol,
1177			alt->desc.bInterfaceClass,
1178			alt->desc.bInterfaceSubClass,
1179			alt->desc.bInterfaceProtocol,
1180			alt->desc.bInterfaceNumber);
1181}
1182static DEVICE_ATTR_RO(modalias);
1183
1184static ssize_t supports_autosuspend_show(struct device *dev,
1185					 struct device_attribute *attr,
1186					 char *buf)
1187{
1188	int s;
1189
1190	s = device_lock_interruptible(dev);
1191	if (s < 0)
1192		return -EINTR;
1193	/* Devices will be autosuspended even when an interface isn't claimed */
1194	s = (!dev->driver || to_usb_driver(dev->driver)->supports_autosuspend);
1195	device_unlock(dev);
1196
1197	return sysfs_emit(buf, "%u\n", s);
1198}
1199static DEVICE_ATTR_RO(supports_autosuspend);
1200
1201/*
1202 * interface_authorized_show - show authorization status of an USB interface
1203 * 1 is authorized, 0 is deauthorized
1204 */
1205static ssize_t interface_authorized_show(struct device *dev,
1206		struct device_attribute *attr, char *buf)
1207{
1208	struct usb_interface *intf = to_usb_interface(dev);
1209
1210	return sysfs_emit(buf, "%u\n", intf->authorized);
1211}
1212
1213/*
1214 * interface_authorized_store - authorize or deauthorize an USB interface
1215 */
1216static ssize_t interface_authorized_store(struct device *dev,
1217		struct device_attribute *attr, const char *buf, size_t count)
1218{
1219	struct usb_interface *intf = to_usb_interface(dev);
1220	bool val;
1221	struct kernfs_node *kn;
1222
1223	if (kstrtobool(buf, &val) != 0)
1224		return -EINVAL;
1225
1226	if (val) {
1227		usb_authorize_interface(intf);
1228	} else {
1229		/*
1230		 * Prevent deadlock if another process is concurrently
1231		 * trying to unregister intf.
1232		 */
1233		kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
1234		if (kn) {
1235			usb_deauthorize_interface(intf);
1236			sysfs_unbreak_active_protection(kn);
1237		}
1238	}
1239
1240	return count;
1241}
1242static struct device_attribute dev_attr_interface_authorized =
1243		__ATTR(authorized, S_IRUGO | S_IWUSR,
1244		interface_authorized_show, interface_authorized_store);
1245
1246static struct attribute *intf_attrs[] = {
1247	&dev_attr_bInterfaceNumber.attr,
1248	&dev_attr_bAlternateSetting.attr,
1249	&dev_attr_bNumEndpoints.attr,
1250	&dev_attr_bInterfaceClass.attr,
1251	&dev_attr_bInterfaceSubClass.attr,
1252	&dev_attr_bInterfaceProtocol.attr,
1253	&dev_attr_modalias.attr,
1254	&dev_attr_supports_autosuspend.attr,
1255	&dev_attr_interface_authorized.attr,
1256	NULL,
1257};
1258static const struct attribute_group intf_attr_grp = {
1259	.attrs = intf_attrs,
1260};
1261
1262static struct attribute *intf_assoc_attrs[] = {
1263	&dev_attr_iad_bFirstInterface.attr,
1264	&dev_attr_iad_bInterfaceCount.attr,
1265	&dev_attr_iad_bFunctionClass.attr,
1266	&dev_attr_iad_bFunctionSubClass.attr,
1267	&dev_attr_iad_bFunctionProtocol.attr,
1268	NULL,
1269};
1270
1271static umode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
1272		struct attribute *a, int n)
1273{
1274	struct device *dev = kobj_to_dev(kobj);
1275	struct usb_interface *intf = to_usb_interface(dev);
1276
1277	if (intf->intf_assoc == NULL)
1278		return 0;
1279	return a->mode;
1280}
1281
1282static const struct attribute_group intf_assoc_attr_grp = {
1283	.attrs =	intf_assoc_attrs,
1284	.is_visible =	intf_assoc_attrs_are_visible,
1285};
1286
1287static ssize_t wireless_status_show(struct device *dev,
1288				    struct device_attribute *attr, char *buf)
1289{
1290	struct usb_interface *intf;
1291
1292	intf = to_usb_interface(dev);
1293	if (intf->wireless_status == USB_WIRELESS_STATUS_DISCONNECTED)
1294		return sysfs_emit(buf, "%s\n", "disconnected");
1295	return sysfs_emit(buf, "%s\n", "connected");
1296}
1297static DEVICE_ATTR_RO(wireless_status);
1298
1299static struct attribute *intf_wireless_status_attrs[] = {
1300	&dev_attr_wireless_status.attr,
1301	NULL
1302};
1303
1304static umode_t intf_wireless_status_attr_is_visible(struct kobject *kobj,
1305		struct attribute *a, int n)
1306{
1307	struct device *dev = kobj_to_dev(kobj);
1308	struct usb_interface *intf = to_usb_interface(dev);
1309
1310	if (a != &dev_attr_wireless_status.attr ||
1311	    intf->wireless_status != USB_WIRELESS_STATUS_NA)
1312		return a->mode;
1313	return 0;
1314}
1315
1316static const struct attribute_group intf_wireless_status_attr_grp = {
1317	.attrs =	intf_wireless_status_attrs,
1318	.is_visible =	intf_wireless_status_attr_is_visible,
1319};
1320
1321int usb_update_wireless_status_attr(struct usb_interface *intf)
1322{
1323	struct device *dev = &intf->dev;
1324	int ret;
1325
1326	ret = sysfs_update_group(&dev->kobj, &intf_wireless_status_attr_grp);
1327	if (ret < 0)
1328		return ret;
1329
1330	sysfs_notify(&dev->kobj, NULL, "wireless_status");
1331	kobject_uevent(&dev->kobj, KOBJ_CHANGE);
1332
1333	return 0;
1334}
1335
1336const struct attribute_group *usb_interface_groups[] = {
1337	&intf_attr_grp,
1338	&intf_assoc_attr_grp,
1339	&intf_wireless_status_attr_grp,
1340	NULL
1341};
1342
1343void usb_create_sysfs_intf_files(struct usb_interface *intf)
1344{
1345	struct usb_device *udev = interface_to_usbdev(intf);
1346	struct usb_host_interface *alt = intf->cur_altsetting;
1347
1348	if (intf->sysfs_files_created || intf->unregistering)
1349		return;
1350
1351	if (!alt->string && !(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
1352		alt->string = usb_cache_string(udev, alt->desc.iInterface);
1353	if (alt->string && device_create_file(&intf->dev, &dev_attr_interface)) {
1354		/* This is not a serious error */
1355		dev_dbg(&intf->dev, "interface string descriptor file not created\n");
1356	}
1357	intf->sysfs_files_created = 1;
1358}
1359
1360void usb_remove_sysfs_intf_files(struct usb_interface *intf)
1361{
1362	if (!intf->sysfs_files_created)
1363		return;
1364
1365	device_remove_file(&intf->dev, &dev_attr_interface);
1366	intf->sysfs_files_created = 0;
1367}
v4.17
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * drivers/usb/core/sysfs.c
   4 *
   5 * (C) Copyright 2002 David Brownell
   6 * (C) Copyright 2002,2004 Greg Kroah-Hartman
   7 * (C) Copyright 2002,2004 IBM Corp.
   8 *
   9 * All of the sysfs file attributes for usb devices and interfaces.
  10 *
  11 * Released under the GPLv2 only.
  12 */
  13
  14
  15#include <linux/kernel.h>
 
  16#include <linux/string.h>
  17#include <linux/usb.h>
 
  18#include <linux/usb/quirks.h>
  19#include <linux/of.h>
  20#include "usb.h"
  21
  22/* Active configuration fields */
  23#define usb_actconfig_show(field, format_string)			\
  24static ssize_t field##_show(struct device *dev,				\
  25			    struct device_attribute *attr, char *buf)	\
  26{									\
  27	struct usb_device *udev;					\
  28	struct usb_host_config *actconfig;				\
  29	ssize_t rc;							\
  30									\
  31	udev = to_usb_device(dev);					\
  32	rc = usb_lock_device_interruptible(udev);			\
  33	if (rc < 0)							\
  34		return -EINTR;						\
  35	actconfig = udev->actconfig;					\
  36	if (actconfig)							\
  37		rc = sprintf(buf, format_string,			\
  38				actconfig->desc.field);			\
  39	usb_unlock_device(udev);					\
  40	return rc;							\
  41}									\
  42
  43#define usb_actconfig_attr(field, format_string)		\
  44	usb_actconfig_show(field, format_string)		\
  45	static DEVICE_ATTR_RO(field)
  46
  47usb_actconfig_attr(bNumInterfaces, "%2d\n");
  48usb_actconfig_attr(bmAttributes, "%2x\n");
  49
  50static ssize_t bMaxPower_show(struct device *dev,
  51		struct device_attribute *attr, char *buf)
  52{
  53	struct usb_device *udev;
  54	struct usb_host_config *actconfig;
  55	ssize_t rc;
  56
  57	udev = to_usb_device(dev);
  58	rc = usb_lock_device_interruptible(udev);
  59	if (rc < 0)
  60		return -EINTR;
  61	actconfig = udev->actconfig;
  62	if (actconfig)
  63		rc = sprintf(buf, "%dmA\n", usb_get_max_power(udev, actconfig));
  64	usb_unlock_device(udev);
  65	return rc;
  66}
  67static DEVICE_ATTR_RO(bMaxPower);
  68
  69static ssize_t configuration_show(struct device *dev,
  70		struct device_attribute *attr, char *buf)
  71{
  72	struct usb_device *udev;
  73	struct usb_host_config *actconfig;
  74	ssize_t rc;
  75
  76	udev = to_usb_device(dev);
  77	rc = usb_lock_device_interruptible(udev);
  78	if (rc < 0)
  79		return -EINTR;
  80	actconfig = udev->actconfig;
  81	if (actconfig && actconfig->string)
  82		rc = sprintf(buf, "%s\n", actconfig->string);
  83	usb_unlock_device(udev);
  84	return rc;
  85}
  86static DEVICE_ATTR_RO(configuration);
  87
  88/* configuration value is always present, and r/w */
  89usb_actconfig_show(bConfigurationValue, "%u\n");
  90
  91static ssize_t bConfigurationValue_store(struct device *dev,
  92					 struct device_attribute *attr,
  93					 const char *buf, size_t count)
  94{
  95	struct usb_device	*udev = to_usb_device(dev);
  96	int			config, value, rc;
  97
  98	if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
  99		return -EINVAL;
 100	rc = usb_lock_device_interruptible(udev);
 101	if (rc < 0)
 102		return -EINTR;
 103	value = usb_set_configuration(udev, config);
 104	usb_unlock_device(udev);
 105	return (value < 0) ? value : count;
 106}
 107static DEVICE_ATTR_IGNORE_LOCKDEP(bConfigurationValue, S_IRUGO | S_IWUSR,
 108		bConfigurationValue_show, bConfigurationValue_store);
 109
 110#ifdef CONFIG_OF
 111static ssize_t devspec_show(struct device *dev, struct device_attribute *attr,
 112			    char *buf)
 113{
 114	struct device_node *of_node = dev->of_node;
 115
 116	return sprintf(buf, "%pOF\n", of_node);
 117}
 118static DEVICE_ATTR_RO(devspec);
 119#endif
 120
 121/* String fields */
 122#define usb_string_attr(name)						\
 123static ssize_t  name##_show(struct device *dev,				\
 124		struct device_attribute *attr, char *buf)		\
 125{									\
 126	struct usb_device *udev;					\
 127	int retval;							\
 128									\
 129	udev = to_usb_device(dev);					\
 130	retval = usb_lock_device_interruptible(udev);			\
 131	if (retval < 0)							\
 132		return -EINTR;						\
 133	retval = sprintf(buf, "%s\n", udev->name);			\
 134	usb_unlock_device(udev);					\
 135	return retval;							\
 136}									\
 137static DEVICE_ATTR_RO(name)
 138
 139usb_string_attr(product);
 140usb_string_attr(manufacturer);
 141usb_string_attr(serial);
 142
 143static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
 144			  char *buf)
 145{
 146	struct usb_device *udev;
 147	char *speed;
 148
 149	udev = to_usb_device(dev);
 150
 151	switch (udev->speed) {
 152	case USB_SPEED_LOW:
 153		speed = "1.5";
 154		break;
 155	case USB_SPEED_UNKNOWN:
 156	case USB_SPEED_FULL:
 157		speed = "12";
 158		break;
 159	case USB_SPEED_HIGH:
 160		speed = "480";
 161		break;
 162	case USB_SPEED_WIRELESS:
 163		speed = "480";
 164		break;
 165	case USB_SPEED_SUPER:
 166		speed = "5000";
 167		break;
 168	case USB_SPEED_SUPER_PLUS:
 169		speed = "10000";
 
 
 
 170		break;
 171	default:
 172		speed = "unknown";
 173	}
 174	return sprintf(buf, "%s\n", speed);
 175}
 176static DEVICE_ATTR_RO(speed);
 177
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 178static ssize_t busnum_show(struct device *dev, struct device_attribute *attr,
 179			   char *buf)
 180{
 181	struct usb_device *udev;
 182
 183	udev = to_usb_device(dev);
 184	return sprintf(buf, "%d\n", udev->bus->busnum);
 185}
 186static DEVICE_ATTR_RO(busnum);
 187
 188static ssize_t devnum_show(struct device *dev, struct device_attribute *attr,
 189			   char *buf)
 190{
 191	struct usb_device *udev;
 192
 193	udev = to_usb_device(dev);
 194	return sprintf(buf, "%d\n", udev->devnum);
 195}
 196static DEVICE_ATTR_RO(devnum);
 197
 198static ssize_t devpath_show(struct device *dev, struct device_attribute *attr,
 199			    char *buf)
 200{
 201	struct usb_device *udev;
 202
 203	udev = to_usb_device(dev);
 204	return sprintf(buf, "%s\n", udev->devpath);
 205}
 206static DEVICE_ATTR_RO(devpath);
 207
 208static ssize_t version_show(struct device *dev, struct device_attribute *attr,
 209			    char *buf)
 210{
 211	struct usb_device *udev;
 212	u16 bcdUSB;
 213
 214	udev = to_usb_device(dev);
 215	bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
 216	return sprintf(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
 217}
 218static DEVICE_ATTR_RO(version);
 219
 220static ssize_t maxchild_show(struct device *dev, struct device_attribute *attr,
 221			     char *buf)
 222{
 223	struct usb_device *udev;
 224
 225	udev = to_usb_device(dev);
 226	return sprintf(buf, "%d\n", udev->maxchild);
 227}
 228static DEVICE_ATTR_RO(maxchild);
 229
 230static ssize_t quirks_show(struct device *dev, struct device_attribute *attr,
 231			   char *buf)
 232{
 233	struct usb_device *udev;
 234
 235	udev = to_usb_device(dev);
 236	return sprintf(buf, "0x%x\n", udev->quirks);
 237}
 238static DEVICE_ATTR_RO(quirks);
 239
 240static ssize_t avoid_reset_quirk_show(struct device *dev,
 241				      struct device_attribute *attr, char *buf)
 242{
 243	struct usb_device *udev;
 244
 245	udev = to_usb_device(dev);
 246	return sprintf(buf, "%d\n", !!(udev->quirks & USB_QUIRK_RESET));
 247}
 248
 249static ssize_t avoid_reset_quirk_store(struct device *dev,
 250				      struct device_attribute *attr,
 251				      const char *buf, size_t count)
 252{
 253	struct usb_device	*udev = to_usb_device(dev);
 254	int			val, rc;
 
 255
 256	if (sscanf(buf, "%d", &val) != 1 || val < 0 || val > 1)
 257		return -EINVAL;
 258	rc = usb_lock_device_interruptible(udev);
 259	if (rc < 0)
 260		return -EINTR;
 261	if (val)
 262		udev->quirks |= USB_QUIRK_RESET;
 263	else
 264		udev->quirks &= ~USB_QUIRK_RESET;
 265	usb_unlock_device(udev);
 266	return count;
 267}
 268static DEVICE_ATTR_RW(avoid_reset_quirk);
 269
 270static ssize_t urbnum_show(struct device *dev, struct device_attribute *attr,
 271			   char *buf)
 272{
 273	struct usb_device *udev;
 274
 275	udev = to_usb_device(dev);
 276	return sprintf(buf, "%d\n", atomic_read(&udev->urbnum));
 277}
 278static DEVICE_ATTR_RO(urbnum);
 279
 280static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
 281			      char *buf)
 282{
 283	struct usb_device *udev;
 284	char *state;
 285
 286	udev = to_usb_device(dev);
 287
 288	switch (udev->removable) {
 289	case USB_DEVICE_REMOVABLE:
 290		state = "removable";
 291		break;
 292	case USB_DEVICE_FIXED:
 293		state = "fixed";
 294		break;
 295	default:
 296		state = "unknown";
 297	}
 298
 299	return sprintf(buf, "%s\n", state);
 300}
 301static DEVICE_ATTR_RO(removable);
 302
 303static ssize_t ltm_capable_show(struct device *dev,
 304				struct device_attribute *attr, char *buf)
 305{
 306	if (usb_device_supports_ltm(to_usb_device(dev)))
 307		return sprintf(buf, "%s\n", "yes");
 308	return sprintf(buf, "%s\n", "no");
 309}
 310static DEVICE_ATTR_RO(ltm_capable);
 311
 312#ifdef	CONFIG_PM
 313
 314static ssize_t persist_show(struct device *dev, struct device_attribute *attr,
 315			    char *buf)
 316{
 317	struct usb_device *udev = to_usb_device(dev);
 318
 319	return sprintf(buf, "%d\n", udev->persist_enabled);
 320}
 321
 322static ssize_t persist_store(struct device *dev, struct device_attribute *attr,
 323			     const char *buf, size_t count)
 324{
 325	struct usb_device *udev = to_usb_device(dev);
 326	int value, rc;
 
 327
 328	/* Hubs are always enabled for USB_PERSIST */
 329	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
 330		return -EPERM;
 331
 332	if (sscanf(buf, "%d", &value) != 1)
 333		return -EINVAL;
 334
 335	rc = usb_lock_device_interruptible(udev);
 336	if (rc < 0)
 337		return -EINTR;
 338	udev->persist_enabled = !!value;
 339	usb_unlock_device(udev);
 340	return count;
 341}
 342static DEVICE_ATTR_RW(persist);
 343
 344static int add_persist_attributes(struct device *dev)
 345{
 346	int rc = 0;
 347
 348	if (is_usb_device(dev)) {
 349		struct usb_device *udev = to_usb_device(dev);
 350
 351		/* Hubs are automatically enabled for USB_PERSIST,
 352		 * no point in creating the attribute file.
 353		 */
 354		if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
 355			rc = sysfs_add_file_to_group(&dev->kobj,
 356					&dev_attr_persist.attr,
 357					power_group_name);
 358	}
 359	return rc;
 360}
 361
 362static void remove_persist_attributes(struct device *dev)
 363{
 364	sysfs_remove_file_from_group(&dev->kobj,
 365			&dev_attr_persist.attr,
 366			power_group_name);
 367}
 368
 369static ssize_t connected_duration_show(struct device *dev,
 370				       struct device_attribute *attr, char *buf)
 371{
 372	struct usb_device *udev = to_usb_device(dev);
 373
 374	return sprintf(buf, "%u\n",
 375			jiffies_to_msecs(jiffies - udev->connect_time));
 376}
 377static DEVICE_ATTR_RO(connected_duration);
 378
 379/*
 380 * If the device is resumed, the last time the device was suspended has
 381 * been pre-subtracted from active_duration.  We add the current time to
 382 * get the duration that the device was actually active.
 383 *
 384 * If the device is suspended, the active_duration is up-to-date.
 385 */
 386static ssize_t active_duration_show(struct device *dev,
 387				    struct device_attribute *attr, char *buf)
 388{
 389	struct usb_device *udev = to_usb_device(dev);
 390	int duration;
 391
 392	if (udev->state != USB_STATE_SUSPENDED)
 393		duration = jiffies_to_msecs(jiffies + udev->active_duration);
 394	else
 395		duration = jiffies_to_msecs(udev->active_duration);
 396	return sprintf(buf, "%u\n", duration);
 397}
 398static DEVICE_ATTR_RO(active_duration);
 399
 400static ssize_t autosuspend_show(struct device *dev,
 401				struct device_attribute *attr, char *buf)
 402{
 403	return sprintf(buf, "%d\n", dev->power.autosuspend_delay / 1000);
 404}
 405
 406static ssize_t autosuspend_store(struct device *dev,
 407				 struct device_attribute *attr, const char *buf,
 408				 size_t count)
 409{
 410	int value;
 411
 412	if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/1000 ||
 413			value <= -INT_MAX/1000)
 414		return -EINVAL;
 415
 416	pm_runtime_set_autosuspend_delay(dev, value * 1000);
 417	return count;
 418}
 419static DEVICE_ATTR_RW(autosuspend);
 420
 421static const char on_string[] = "on";
 422static const char auto_string[] = "auto";
 423
 424static void warn_level(void)
 425{
 426	static int level_warned;
 427
 428	if (!level_warned) {
 429		level_warned = 1;
 430		printk(KERN_WARNING "WARNING! power/level is deprecated; "
 431				"use power/control instead\n");
 432	}
 433}
 434
 435static ssize_t level_show(struct device *dev, struct device_attribute *attr,
 436			  char *buf)
 437{
 438	struct usb_device *udev = to_usb_device(dev);
 439	const char *p = auto_string;
 440
 441	warn_level();
 442	if (udev->state != USB_STATE_SUSPENDED && !udev->dev.power.runtime_auto)
 443		p = on_string;
 444	return sprintf(buf, "%s\n", p);
 445}
 446
 447static ssize_t level_store(struct device *dev, struct device_attribute *attr,
 448			   const char *buf, size_t count)
 449{
 450	struct usb_device *udev = to_usb_device(dev);
 451	int len = count;
 452	char *cp;
 453	int rc = count;
 454	int rv;
 455
 456	warn_level();
 457	cp = memchr(buf, '\n', count);
 458	if (cp)
 459		len = cp - buf;
 460
 461	rv = usb_lock_device_interruptible(udev);
 462	if (rv < 0)
 463		return -EINTR;
 464
 465	if (len == sizeof on_string - 1 &&
 466			strncmp(buf, on_string, len) == 0)
 467		usb_disable_autosuspend(udev);
 468
 469	else if (len == sizeof auto_string - 1 &&
 470			strncmp(buf, auto_string, len) == 0)
 471		usb_enable_autosuspend(udev);
 472
 473	else
 474		rc = -EINVAL;
 475
 476	usb_unlock_device(udev);
 477	return rc;
 478}
 479static DEVICE_ATTR_RW(level);
 480
 481static ssize_t usb2_hardware_lpm_show(struct device *dev,
 482				      struct device_attribute *attr, char *buf)
 483{
 484	struct usb_device *udev = to_usb_device(dev);
 485	const char *p;
 486
 487	if (udev->usb2_hw_lpm_allowed == 1)
 488		p = "enabled";
 489	else
 490		p = "disabled";
 491
 492	return sprintf(buf, "%s\n", p);
 493}
 494
 495static ssize_t usb2_hardware_lpm_store(struct device *dev,
 496				       struct device_attribute *attr,
 497				       const char *buf, size_t count)
 498{
 499	struct usb_device *udev = to_usb_device(dev);
 500	bool value;
 501	int ret;
 502
 503	ret = usb_lock_device_interruptible(udev);
 504	if (ret < 0)
 505		return -EINTR;
 506
 507	ret = strtobool(buf, &value);
 508
 509	if (!ret) {
 510		udev->usb2_hw_lpm_allowed = value;
 511		ret = usb_set_usb2_hardware_lpm(udev, value);
 
 
 
 512	}
 513
 514	usb_unlock_device(udev);
 515
 516	if (!ret)
 517		return count;
 518
 519	return ret;
 520}
 521static DEVICE_ATTR_RW(usb2_hardware_lpm);
 522
 523static ssize_t usb2_lpm_l1_timeout_show(struct device *dev,
 524					struct device_attribute *attr,
 525					char *buf)
 526{
 527	struct usb_device *udev = to_usb_device(dev);
 528	return sprintf(buf, "%d\n", udev->l1_params.timeout);
 529}
 530
 531static ssize_t usb2_lpm_l1_timeout_store(struct device *dev,
 532					 struct device_attribute *attr,
 533					 const char *buf, size_t count)
 534{
 535	struct usb_device *udev = to_usb_device(dev);
 536	u16 timeout;
 537
 538	if (kstrtou16(buf, 0, &timeout))
 539		return -EINVAL;
 540
 541	udev->l1_params.timeout = timeout;
 542
 543	return count;
 544}
 545static DEVICE_ATTR_RW(usb2_lpm_l1_timeout);
 546
 547static ssize_t usb2_lpm_besl_show(struct device *dev,
 548				  struct device_attribute *attr, char *buf)
 549{
 550	struct usb_device *udev = to_usb_device(dev);
 551	return sprintf(buf, "%d\n", udev->l1_params.besl);
 552}
 553
 554static ssize_t usb2_lpm_besl_store(struct device *dev,
 555				   struct device_attribute *attr,
 556				   const char *buf, size_t count)
 557{
 558	struct usb_device *udev = to_usb_device(dev);
 559	u8 besl;
 560
 561	if (kstrtou8(buf, 0, &besl) || besl > 15)
 562		return -EINVAL;
 563
 564	udev->l1_params.besl = besl;
 565
 566	return count;
 567}
 568static DEVICE_ATTR_RW(usb2_lpm_besl);
 569
 570static ssize_t usb3_hardware_lpm_u1_show(struct device *dev,
 571				      struct device_attribute *attr, char *buf)
 572{
 573	struct usb_device *udev = to_usb_device(dev);
 574	const char *p;
 575	int rc;
 576
 577	rc = usb_lock_device_interruptible(udev);
 578	if (rc < 0)
 579		return -EINTR;
 580
 581	if (udev->usb3_lpm_u1_enabled)
 582		p = "enabled";
 583	else
 584		p = "disabled";
 585
 586	usb_unlock_device(udev);
 587
 588	return sprintf(buf, "%s\n", p);
 589}
 590static DEVICE_ATTR_RO(usb3_hardware_lpm_u1);
 591
 592static ssize_t usb3_hardware_lpm_u2_show(struct device *dev,
 593				      struct device_attribute *attr, char *buf)
 594{
 595	struct usb_device *udev = to_usb_device(dev);
 596	const char *p;
 597	int rc;
 598
 599	rc = usb_lock_device_interruptible(udev);
 600	if (rc < 0)
 601		return -EINTR;
 602
 603	if (udev->usb3_lpm_u2_enabled)
 604		p = "enabled";
 605	else
 606		p = "disabled";
 607
 608	usb_unlock_device(udev);
 609
 610	return sprintf(buf, "%s\n", p);
 611}
 612static DEVICE_ATTR_RO(usb3_hardware_lpm_u2);
 613
 614static struct attribute *usb2_hardware_lpm_attr[] = {
 615	&dev_attr_usb2_hardware_lpm.attr,
 616	&dev_attr_usb2_lpm_l1_timeout.attr,
 617	&dev_attr_usb2_lpm_besl.attr,
 618	NULL,
 619};
 620static struct attribute_group usb2_hardware_lpm_attr_group = {
 621	.name	= power_group_name,
 622	.attrs	= usb2_hardware_lpm_attr,
 623};
 624
 625static struct attribute *usb3_hardware_lpm_attr[] = {
 626	&dev_attr_usb3_hardware_lpm_u1.attr,
 627	&dev_attr_usb3_hardware_lpm_u2.attr,
 628	NULL,
 629};
 630static struct attribute_group usb3_hardware_lpm_attr_group = {
 631	.name	= power_group_name,
 632	.attrs	= usb3_hardware_lpm_attr,
 633};
 634
 635static struct attribute *power_attrs[] = {
 636	&dev_attr_autosuspend.attr,
 637	&dev_attr_level.attr,
 638	&dev_attr_connected_duration.attr,
 639	&dev_attr_active_duration.attr,
 640	NULL,
 641};
 642static struct attribute_group power_attr_group = {
 643	.name	= power_group_name,
 644	.attrs	= power_attrs,
 645};
 646
 647static int add_power_attributes(struct device *dev)
 648{
 649	int rc = 0;
 650
 651	if (is_usb_device(dev)) {
 652		struct usb_device *udev = to_usb_device(dev);
 653		rc = sysfs_merge_group(&dev->kobj, &power_attr_group);
 654		if (udev->usb2_hw_lpm_capable == 1)
 655			rc = sysfs_merge_group(&dev->kobj,
 656					&usb2_hardware_lpm_attr_group);
 657		if ((udev->speed == USB_SPEED_SUPER ||
 658		     udev->speed == USB_SPEED_SUPER_PLUS) &&
 659				udev->lpm_capable == 1)
 660			rc = sysfs_merge_group(&dev->kobj,
 661					&usb3_hardware_lpm_attr_group);
 662	}
 663
 664	return rc;
 665}
 666
 667static void remove_power_attributes(struct device *dev)
 668{
 
 669	sysfs_unmerge_group(&dev->kobj, &usb2_hardware_lpm_attr_group);
 670	sysfs_unmerge_group(&dev->kobj, &power_attr_group);
 671}
 672
 673#else
 674
 675#define add_persist_attributes(dev)	0
 676#define remove_persist_attributes(dev)	do {} while (0)
 677
 678#define add_power_attributes(dev)	0
 679#define remove_power_attributes(dev)	do {} while (0)
 680
 681#endif	/* CONFIG_PM */
 682
 683
 684/* Descriptor fields */
 685#define usb_descriptor_attr_le16(field, format_string)			\
 686static ssize_t								\
 687field##_show(struct device *dev, struct device_attribute *attr,	\
 688		char *buf)						\
 689{									\
 690	struct usb_device *udev;					\
 691									\
 692	udev = to_usb_device(dev);					\
 693	return sprintf(buf, format_string, 				\
 694			le16_to_cpu(udev->descriptor.field));		\
 695}									\
 696static DEVICE_ATTR_RO(field)
 697
 698usb_descriptor_attr_le16(idVendor, "%04x\n");
 699usb_descriptor_attr_le16(idProduct, "%04x\n");
 700usb_descriptor_attr_le16(bcdDevice, "%04x\n");
 701
 702#define usb_descriptor_attr(field, format_string)			\
 703static ssize_t								\
 704field##_show(struct device *dev, struct device_attribute *attr,	\
 705		char *buf)						\
 706{									\
 707	struct usb_device *udev;					\
 708									\
 709	udev = to_usb_device(dev);					\
 710	return sprintf(buf, format_string, udev->descriptor.field);	\
 711}									\
 712static DEVICE_ATTR_RO(field)
 713
 714usb_descriptor_attr(bDeviceClass, "%02x\n");
 715usb_descriptor_attr(bDeviceSubClass, "%02x\n");
 716usb_descriptor_attr(bDeviceProtocol, "%02x\n");
 717usb_descriptor_attr(bNumConfigurations, "%d\n");
 718usb_descriptor_attr(bMaxPacketSize0, "%d\n");
 719
 720
 721/* show if the device is authorized (1) or not (0) */
 722static ssize_t authorized_show(struct device *dev,
 723			       struct device_attribute *attr, char *buf)
 724{
 725	struct usb_device *usb_dev = to_usb_device(dev);
 726	return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
 727}
 728
 729/*
 730 * Authorize a device to be used in the system
 731 *
 732 * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
 733 */
 734static ssize_t authorized_store(struct device *dev,
 735				struct device_attribute *attr, const char *buf,
 736				size_t size)
 737{
 738	ssize_t result;
 739	struct usb_device *usb_dev = to_usb_device(dev);
 740	unsigned val;
 741	result = sscanf(buf, "%u\n", &val);
 742	if (result != 1)
 743		result = -EINVAL;
 744	else if (val == 0)
 
 
 745		result = usb_deauthorize_device(usb_dev);
 746	else
 747		result = usb_authorize_device(usb_dev);
 748	return result < 0 ? result : size;
 749}
 750static DEVICE_ATTR_IGNORE_LOCKDEP(authorized, S_IRUGO | S_IWUSR,
 751				  authorized_show, authorized_store);
 752
 753/* "Safely remove a device" */
 754static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
 755			    const char *buf, size_t count)
 756{
 757	struct usb_device *udev = to_usb_device(dev);
 758	int rc = 0;
 759
 760	usb_lock_device(udev);
 761	if (udev->state != USB_STATE_NOTATTACHED) {
 762
 763		/* To avoid races, first unconfigure and then remove */
 764		usb_set_configuration(udev, -1);
 765		rc = usb_remove_device(udev);
 766	}
 767	if (rc == 0)
 768		rc = count;
 769	usb_unlock_device(udev);
 770	return rc;
 771}
 772static DEVICE_ATTR_IGNORE_LOCKDEP(remove, S_IWUSR, NULL, remove_store);
 773
 774
 775static struct attribute *dev_attrs[] = {
 776	/* current configuration's attributes */
 777	&dev_attr_configuration.attr,
 778	&dev_attr_bNumInterfaces.attr,
 779	&dev_attr_bConfigurationValue.attr,
 780	&dev_attr_bmAttributes.attr,
 781	&dev_attr_bMaxPower.attr,
 782	/* device attributes */
 783	&dev_attr_urbnum.attr,
 784	&dev_attr_idVendor.attr,
 785	&dev_attr_idProduct.attr,
 786	&dev_attr_bcdDevice.attr,
 787	&dev_attr_bDeviceClass.attr,
 788	&dev_attr_bDeviceSubClass.attr,
 789	&dev_attr_bDeviceProtocol.attr,
 790	&dev_attr_bNumConfigurations.attr,
 791	&dev_attr_bMaxPacketSize0.attr,
 792	&dev_attr_speed.attr,
 
 
 793	&dev_attr_busnum.attr,
 794	&dev_attr_devnum.attr,
 795	&dev_attr_devpath.attr,
 796	&dev_attr_version.attr,
 797	&dev_attr_maxchild.attr,
 798	&dev_attr_quirks.attr,
 799	&dev_attr_avoid_reset_quirk.attr,
 800	&dev_attr_authorized.attr,
 801	&dev_attr_remove.attr,
 802	&dev_attr_removable.attr,
 803	&dev_attr_ltm_capable.attr,
 804#ifdef CONFIG_OF
 805	&dev_attr_devspec.attr,
 806#endif
 807	NULL,
 808};
 809static struct attribute_group dev_attr_grp = {
 810	.attrs = dev_attrs,
 811};
 812
 813/* When modifying this list, be sure to modify dev_string_attrs_are_visible()
 814 * accordingly.
 815 */
 816static struct attribute *dev_string_attrs[] = {
 817	&dev_attr_manufacturer.attr,
 818	&dev_attr_product.attr,
 819	&dev_attr_serial.attr,
 820	NULL
 821};
 822
 823static umode_t dev_string_attrs_are_visible(struct kobject *kobj,
 824		struct attribute *a, int n)
 825{
 826	struct device *dev = container_of(kobj, struct device, kobj);
 827	struct usb_device *udev = to_usb_device(dev);
 828
 829	if (a == &dev_attr_manufacturer.attr) {
 830		if (udev->manufacturer == NULL)
 831			return 0;
 832	} else if (a == &dev_attr_product.attr) {
 833		if (udev->product == NULL)
 834			return 0;
 835	} else if (a == &dev_attr_serial.attr) {
 836		if (udev->serial == NULL)
 837			return 0;
 838	}
 839	return a->mode;
 840}
 841
 842static struct attribute_group dev_string_attr_grp = {
 843	.attrs =	dev_string_attrs,
 844	.is_visible =	dev_string_attrs_are_visible,
 845};
 846
 847const struct attribute_group *usb_device_groups[] = {
 848	&dev_attr_grp,
 849	&dev_string_attr_grp,
 850	NULL
 851};
 852
 853/* Binary descriptors */
 854
 855static ssize_t
 856read_descriptors(struct file *filp, struct kobject *kobj,
 857		struct bin_attribute *attr,
 858		char *buf, loff_t off, size_t count)
 859{
 860	struct device *dev = container_of(kobj, struct device, kobj);
 861	struct usb_device *udev = to_usb_device(dev);
 862	size_t nleft = count;
 863	size_t srclen, n;
 864	int cfgno;
 865	void *src;
 866
 867	/* The binary attribute begins with the device descriptor.
 868	 * Following that are the raw descriptor entries for all the
 869	 * configurations (config plus subsidiary descriptors).
 870	 */
 871	for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
 872			nleft > 0; ++cfgno) {
 873		if (cfgno < 0) {
 874			src = &udev->descriptor;
 875			srclen = sizeof(struct usb_device_descriptor);
 876		} else {
 877			src = udev->rawdescriptors[cfgno];
 878			srclen = __le16_to_cpu(udev->config[cfgno].desc.
 879					wTotalLength);
 880		}
 881		if (off < srclen) {
 882			n = min(nleft, srclen - (size_t) off);
 883			memcpy(buf, src + off, n);
 884			nleft -= n;
 885			buf += n;
 886			off = 0;
 887		} else {
 888			off -= srclen;
 889		}
 890	}
 891	return count - nleft;
 892}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 893
 894static struct bin_attribute dev_bin_attr_descriptors = {
 895	.attr = {.name = "descriptors", .mode = 0444},
 896	.read = read_descriptors,
 897	.size = 18 + 65535,	/* dev descr + max-size raw descriptor */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 898};
 899
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 900int usb_create_sysfs_dev_files(struct usb_device *udev)
 901{
 902	struct device *dev = &udev->dev;
 903	int retval;
 904
 905	retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
 906	if (retval)
 907		goto error;
 908
 909	retval = add_persist_attributes(dev);
 910	if (retval)
 911		goto error;
 912
 913	retval = add_power_attributes(dev);
 914	if (retval)
 915		goto error;
 
 
 
 
 
 
 916	return retval;
 
 917error:
 918	usb_remove_sysfs_dev_files(udev);
 919	return retval;
 920}
 921
 922void usb_remove_sysfs_dev_files(struct usb_device *udev)
 923{
 924	struct device *dev = &udev->dev;
 925
 
 
 
 926	remove_power_attributes(dev);
 927	remove_persist_attributes(dev);
 928	device_remove_bin_file(dev, &dev_bin_attr_descriptors);
 929}
 930
 931/* Interface Association Descriptor fields */
 932#define usb_intf_assoc_attr(field, format_string)			\
 933static ssize_t								\
 934iad_##field##_show(struct device *dev, struct device_attribute *attr,	\
 935		char *buf)						\
 936{									\
 937	struct usb_interface *intf = to_usb_interface(dev);		\
 938									\
 939	return sprintf(buf, format_string,				\
 940			intf->intf_assoc->field); 			\
 941}									\
 942static DEVICE_ATTR_RO(iad_##field)
 943
 944usb_intf_assoc_attr(bFirstInterface, "%02x\n");
 945usb_intf_assoc_attr(bInterfaceCount, "%02d\n");
 946usb_intf_assoc_attr(bFunctionClass, "%02x\n");
 947usb_intf_assoc_attr(bFunctionSubClass, "%02x\n");
 948usb_intf_assoc_attr(bFunctionProtocol, "%02x\n");
 949
 950/* Interface fields */
 951#define usb_intf_attr(field, format_string)				\
 952static ssize_t								\
 953field##_show(struct device *dev, struct device_attribute *attr,		\
 954		char *buf)						\
 955{									\
 956	struct usb_interface *intf = to_usb_interface(dev);		\
 957									\
 958	return sprintf(buf, format_string,				\
 959			intf->cur_altsetting->desc.field); 		\
 960}									\
 961static DEVICE_ATTR_RO(field)
 962
 963usb_intf_attr(bInterfaceNumber, "%02x\n");
 964usb_intf_attr(bAlternateSetting, "%2d\n");
 965usb_intf_attr(bNumEndpoints, "%02x\n");
 966usb_intf_attr(bInterfaceClass, "%02x\n");
 967usb_intf_attr(bInterfaceSubClass, "%02x\n");
 968usb_intf_attr(bInterfaceProtocol, "%02x\n");
 969
 970static ssize_t interface_show(struct device *dev, struct device_attribute *attr,
 971			      char *buf)
 972{
 973	struct usb_interface *intf;
 974	char *string;
 975
 976	intf = to_usb_interface(dev);
 977	string = READ_ONCE(intf->cur_altsetting->string);
 978	if (!string)
 979		return 0;
 980	return sprintf(buf, "%s\n", string);
 981}
 982static DEVICE_ATTR_RO(interface);
 983
 984static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 985			     char *buf)
 986{
 987	struct usb_interface *intf;
 988	struct usb_device *udev;
 989	struct usb_host_interface *alt;
 990
 991	intf = to_usb_interface(dev);
 992	udev = interface_to_usbdev(intf);
 993	alt = READ_ONCE(intf->cur_altsetting);
 994
 995	return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
 
 996			"ic%02Xisc%02Xip%02Xin%02X\n",
 997			le16_to_cpu(udev->descriptor.idVendor),
 998			le16_to_cpu(udev->descriptor.idProduct),
 999			le16_to_cpu(udev->descriptor.bcdDevice),
1000			udev->descriptor.bDeviceClass,
1001			udev->descriptor.bDeviceSubClass,
1002			udev->descriptor.bDeviceProtocol,
1003			alt->desc.bInterfaceClass,
1004			alt->desc.bInterfaceSubClass,
1005			alt->desc.bInterfaceProtocol,
1006			alt->desc.bInterfaceNumber);
1007}
1008static DEVICE_ATTR_RO(modalias);
1009
1010static ssize_t supports_autosuspend_show(struct device *dev,
1011					 struct device_attribute *attr,
1012					 char *buf)
1013{
1014	int s;
1015
1016	s = device_lock_interruptible(dev);
1017	if (s < 0)
1018		return -EINTR;
1019	/* Devices will be autosuspended even when an interface isn't claimed */
1020	s = (!dev->driver || to_usb_driver(dev->driver)->supports_autosuspend);
1021	device_unlock(dev);
1022
1023	return sprintf(buf, "%u\n", s);
1024}
1025static DEVICE_ATTR_RO(supports_autosuspend);
1026
1027/*
1028 * interface_authorized_show - show authorization status of an USB interface
1029 * 1 is authorized, 0 is deauthorized
1030 */
1031static ssize_t interface_authorized_show(struct device *dev,
1032		struct device_attribute *attr, char *buf)
1033{
1034	struct usb_interface *intf = to_usb_interface(dev);
1035
1036	return sprintf(buf, "%u\n", intf->authorized);
1037}
1038
1039/*
1040 * interface_authorized_store - authorize or deauthorize an USB interface
1041 */
1042static ssize_t interface_authorized_store(struct device *dev,
1043		struct device_attribute *attr, const char *buf, size_t count)
1044{
1045	struct usb_interface *intf = to_usb_interface(dev);
1046	bool val;
 
1047
1048	if (strtobool(buf, &val) != 0)
1049		return -EINVAL;
1050
1051	if (val)
1052		usb_authorize_interface(intf);
1053	else
1054		usb_deauthorize_interface(intf);
 
 
 
 
 
 
 
 
 
1055
1056	return count;
1057}
1058static struct device_attribute dev_attr_interface_authorized =
1059		__ATTR(authorized, S_IRUGO | S_IWUSR,
1060		interface_authorized_show, interface_authorized_store);
1061
1062static struct attribute *intf_attrs[] = {
1063	&dev_attr_bInterfaceNumber.attr,
1064	&dev_attr_bAlternateSetting.attr,
1065	&dev_attr_bNumEndpoints.attr,
1066	&dev_attr_bInterfaceClass.attr,
1067	&dev_attr_bInterfaceSubClass.attr,
1068	&dev_attr_bInterfaceProtocol.attr,
1069	&dev_attr_modalias.attr,
1070	&dev_attr_supports_autosuspend.attr,
1071	&dev_attr_interface_authorized.attr,
1072	NULL,
1073};
1074static struct attribute_group intf_attr_grp = {
1075	.attrs = intf_attrs,
1076};
1077
1078static struct attribute *intf_assoc_attrs[] = {
1079	&dev_attr_iad_bFirstInterface.attr,
1080	&dev_attr_iad_bInterfaceCount.attr,
1081	&dev_attr_iad_bFunctionClass.attr,
1082	&dev_attr_iad_bFunctionSubClass.attr,
1083	&dev_attr_iad_bFunctionProtocol.attr,
1084	NULL,
1085};
1086
1087static umode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
1088		struct attribute *a, int n)
1089{
1090	struct device *dev = container_of(kobj, struct device, kobj);
1091	struct usb_interface *intf = to_usb_interface(dev);
1092
1093	if (intf->intf_assoc == NULL)
1094		return 0;
1095	return a->mode;
1096}
1097
1098static struct attribute_group intf_assoc_attr_grp = {
1099	.attrs =	intf_assoc_attrs,
1100	.is_visible =	intf_assoc_attrs_are_visible,
1101};
1102
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1103const struct attribute_group *usb_interface_groups[] = {
1104	&intf_attr_grp,
1105	&intf_assoc_attr_grp,
 
1106	NULL
1107};
1108
1109void usb_create_sysfs_intf_files(struct usb_interface *intf)
1110{
1111	struct usb_device *udev = interface_to_usbdev(intf);
1112	struct usb_host_interface *alt = intf->cur_altsetting;
1113
1114	if (intf->sysfs_files_created || intf->unregistering)
1115		return;
1116
1117	if (!alt->string && !(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
1118		alt->string = usb_cache_string(udev, alt->desc.iInterface);
1119	if (alt->string && device_create_file(&intf->dev, &dev_attr_interface))
1120		;	/* We don't actually care if the function fails. */
 
 
1121	intf->sysfs_files_created = 1;
1122}
1123
1124void usb_remove_sysfs_intf_files(struct usb_interface *intf)
1125{
1126	if (!intf->sysfs_files_created)
1127		return;
1128
1129	device_remove_file(&intf->dev, &dev_attr_interface);
1130	intf->sysfs_files_created = 0;
1131}