drivers/usb/core/sysfs.c

   1 /*
   2  * drivers/usb/core/sysfs.c
   3  *
   4  * (C) Copyright 2002 David Brownell
   5  * (C) Copyright 2002,2004 Greg Kroah-Hartman
   6  * (C) Copyright 2002,2004 IBM Corp.
   7  *
   8  * All of the sysfs file attributes for usb devices and interfaces.
   9  *
  10  */
  11
  12
  13 #include <linux/kernel.h>
  14 #include <linux/string.h>
  15 #include <linux/usb.h>
  16 #include "usb.h"
  17
  18 /* Active configuration fields */
  19 #define usb_actconfig_show(field, multiplier, format_string)            \
  20 static ssize_t  show_##field(struct device *dev,                        \
  21                 struct device_attribute *attr, char *buf)               \
  22 {                                                                       \
  23         struct usb_device *udev;                                        \
  24         struct usb_host_config *actconfig;                              \
  25                                                                         \
  26         udev = to_usb_device(dev);                                      \
  27         actconfig = udev->actconfig;                                    \
  28         if (actconfig)                                                  \
  29                 return sprintf(buf, format_string,                      \
  30                                 actconfig->desc.field * multiplier);    \
  31         else                                                            \
  32                 return 0;                                               \
  33 }                                                                       \
  34
  35 #define usb_actconfig_attr(field, multiplier, format_string)            \
  36 usb_actconfig_show(field, multiplier, format_string)                    \
  37 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
  38
  39 usb_actconfig_attr(bNumInterfaces, 1, "%2d\n")
  40 usb_actconfig_attr(bmAttributes, 1, "%2x\n")
  41 usb_actconfig_attr(bMaxPower, 2, "%3dmA\n")
  42
  43 static ssize_t show_configuration_string(struct device *dev,
  44                 struct device_attribute *attr, char *buf)
  45 {
  46         struct usb_device *udev;
  47         struct usb_host_config *actconfig;
  48
  49         udev = to_usb_device(dev);
  50         actconfig = udev->actconfig;
  51         if ((!actconfig) || (!actconfig->string))
  52                 return 0;
  53         return sprintf(buf, "%s\n", actconfig->string);
  54 }
  55 static DEVICE_ATTR(configuration, S_IRUGO, show_configuration_string, NULL);
  56
  57 /* configuration value is always present, and r/w */
  58 usb_actconfig_show(bConfigurationValue, 1, "%u\n");
  59
  60 static ssize_t
  61 set_bConfigurationValue(struct device *dev, struct device_attribute *attr,
  62                 const char *buf, size_t count)
  63 {
  64         struct usb_device       *udev = to_usb_device(dev);
  65         int                     config, value;
  66
  67         if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
  68                 return -EINVAL;
  69         usb_lock_device(udev);
  70         value = usb_set_configuration(udev, config);
  71         usb_unlock_device(udev);
  72         return (value < 0) ? value : count;
  73 }
  74
  75 static DEVICE_ATTR(bConfigurationValue, S_IRUGO | S_IWUSR,
  76                 show_bConfigurationValue, set_bConfigurationValue);
  77
  78 /* String fields */
  79 #define usb_string_attr(name)                                           \
  80 static ssize_t  show_##name(struct device *dev,                         \
  81                 struct device_attribute *attr, char *buf)               \
  82 {                                                                       \
  83         struct usb_device *udev;                                        \
  84                                                                         \
  85         udev = to_usb_device(dev);                                      \
  86         return sprintf(buf, "%s\n", udev->name);                        \
  87 }                                                                       \
  88 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
  89
  90 usb_string_attr(product);
  91 usb_string_attr(manufacturer);
  92 usb_string_attr(serial);
  93
  94 static ssize_t
  95 show_speed(struct device *dev, struct device_attribute *attr, char *buf)
  96 {
  97         struct usb_device *udev;
  98         char *speed;
  99
 100         udev = to_usb_device(dev);
 101
 102         switch (udev->speed) {
 103         case USB_SPEED_LOW:
 104                 speed = "1.5";
 105                 break;
 106         case USB_SPEED_UNKNOWN:
 107         case USB_SPEED_FULL:
 108                 speed = "12";
 109                 break;
 110         case USB_SPEED_HIGH:
 111                 speed = "480";
 112                 break;
 113         default:
 114                 speed = "unknown";
 115         }
 116         return sprintf(buf, "%s\n", speed);
 117 }
 118 static DEVICE_ATTR(speed, S_IRUGO, show_speed, NULL);
 119
 120 static ssize_t
 121 show_busnum(struct device *dev, struct device_attribute *attr, char *buf)
 122 {
 123         struct usb_device *udev;
 124
 125         udev = to_usb_device(dev);
 126         return sprintf(buf, "%d\n", udev->bus->busnum);
 127 }
 128 static DEVICE_ATTR(busnum, S_IRUGO, show_busnum, NULL);
 129
 130 static ssize_t
 131 show_devnum(struct device *dev, struct device_attribute *attr, char *buf)
 132 {
 133         struct usb_device *udev;
 134
 135         udev = to_usb_device(dev);
 136         return sprintf(buf, "%d\n", udev->devnum);
 137 }
 138 static DEVICE_ATTR(devnum, S_IRUGO, show_devnum, NULL);
 139
 140 static ssize_t
 141 show_version(struct device *dev, struct device_attribute *attr, char *buf)
 142 {
 143         struct usb_device *udev;
 144         u16 bcdUSB;
 145
 146         udev = to_usb_device(dev);
 147         bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
 148         return sprintf(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
 149 }
 150 static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
 151
 152 static ssize_t
 153 show_maxchild(struct device *dev, struct device_attribute *attr, char *buf)
 154 {
 155         struct usb_device *udev;
 156
 157         udev = to_usb_device(dev);
 158         return sprintf(buf, "%d\n", udev->maxchild);
 159 }
 160 static DEVICE_ATTR(maxchild, S_IRUGO, show_maxchild, NULL);
 161
 162 static ssize_t
 163 show_quirks(struct device *dev, struct device_attribute *attr, char *buf)
 164 {
 165         struct usb_device *udev;
 166
 167         udev = to_usb_device(dev);
 168         return sprintf(buf, "0x%x\n", udev->quirks);
 169 }
 170 static DEVICE_ATTR(quirks, S_IRUGO, show_quirks, NULL);
 171
 172 static ssize_t
 173 show_urbnum(struct device *dev, struct device_attribute *attr, char *buf)
 174 {
 175         struct usb_device *udev;
 176
 177         udev = to_usb_device(dev);
 178         return sprintf(buf, "%d\n", atomic_read(&udev->urbnum));
 179 }
 180 static DEVICE_ATTR(urbnum, S_IRUGO, show_urbnum, NULL);
 181
 182
 183 #if defined(CONFIG_USB_PERSIST) || defined(CONFIG_USB_SUSPEND)
 184 static const char power_group[] = "power";
 185 #endif
 186
 187 #ifdef  CONFIG_USB_PERSIST
 188
 189 static ssize_t
 190 show_persist(struct device *dev, struct device_attribute *attr, char *buf)
 191 {
 192         struct usb_device *udev = to_usb_device(dev);
 193
 194         return sprintf(buf, "%d\n", udev->persist_enabled);
 195 }
 196
 197 static ssize_t
 198 set_persist(struct device *dev, struct device_attribute *attr,
 199                 const char *buf, size_t count)
 200 {
 201         struct usb_device *udev = to_usb_device(dev);
 202         int value;
 203
 204         /* Hubs are always enabled for USB_PERSIST */
 205         if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
 206                 return -EPERM;
 207
 208         if (sscanf(buf, "%d", &value) != 1)
 209                 return -EINVAL;
 210         usb_pm_lock(udev);
 211         udev->persist_enabled = !!value;
 212         usb_pm_unlock(udev);
 213         return count;
 214 }
 215
 216 static DEVICE_ATTR(persist, S_IRUGO | S_IWUSR, show_persist, set_persist);
 217
 218 static int add_persist_attributes(struct device *dev)
 219 {
 220         int rc = 0;
 221
 222         if (is_usb_device(dev)) {
 223                 struct usb_device *udev = to_usb_device(dev);
 224
 225                 /* Hubs are automatically enabled for USB_PERSIST */
 226                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
 227                         udev->persist_enabled = 1;
 228                 rc = sysfs_add_file_to_group(&dev->kobj,
 229                                 &dev_attr_persist.attr,
 230                                 power_group);
 231         }
 232         return rc;
 233 }
 234
 235 static void remove_persist_attributes(struct device *dev)
 236 {
 237         sysfs_remove_file_from_group(&dev->kobj,
 238                         &dev_attr_persist.attr,
 239                         power_group);
 240 }
 241
 242 #else
 243
 244 #define add_persist_attributes(dev)     0
 245 #define remove_persist_attributes(dev)  do {} while (0)
 246
 247 #endif  /* CONFIG_USB_PERSIST */
 248
 249 #ifdef  CONFIG_USB_SUSPEND
 250
 251 static ssize_t
 252 show_autosuspend(struct device *dev, struct device_attribute *attr, char *buf)
 253 {
 254         struct usb_device *udev = to_usb_device(dev);
 255
 256         return sprintf(buf, "%d\n", udev->autosuspend_delay / HZ);
 257 }
 258
 259 static ssize_t
 260 set_autosuspend(struct device *dev, struct device_attribute *attr,
 261                 const char *buf, size_t count)
 262 {
 263         struct usb_device *udev = to_usb_device(dev);
 264         int value;
 265
 266         if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/HZ ||
 267                         value <= - INT_MAX/HZ)
 268                 return -EINVAL;
 269         value *= HZ;
 270
 271         udev->autosuspend_delay = value;
 272         if (value >= 0)
 273                 usb_try_autosuspend_device(udev);
 274         else {
 275                 if (usb_autoresume_device(udev) == 0)
 276                         usb_autosuspend_device(udev);
 277         }
 278         return count;
 279 }
 280
 281 static DEVICE_ATTR(autosuspend, S_IRUGO | S_IWUSR,
 282                 show_autosuspend, set_autosuspend);
 283
 284 static const char on_string[] = "on";
 285 static const char auto_string[] = "auto";
 286 static const char suspend_string[] = "suspend";
 287
 288 static ssize_t
 289 show_level(struct device *dev, struct device_attribute *attr, char *buf)
 290 {
 291         struct usb_device *udev = to_usb_device(dev);
 292         const char *p = auto_string;
 293
 294         if (udev->state == USB_STATE_SUSPENDED) {
 295                 if (udev->autoresume_disabled)
 296                         p = suspend_string;
 297         } else {
 298                 if (udev->autosuspend_disabled)
 299                         p = on_string;
 300         }
 301         return sprintf(buf, "%s\n", p);
 302 }
 303
 304 static ssize_t
 305 set_level(struct device *dev, struct device_attribute *attr,
 306                 const char *buf, size_t count)
 307 {
 308         struct usb_device *udev = to_usb_device(dev);
 309         int len = count;
 310         char *cp;
 311         int rc = 0;
 312         int old_autosuspend_disabled, old_autoresume_disabled;
 313
 314         cp = memchr(buf, '\n', count);
 315         if (cp)
 316                 len = cp - buf;
 317
 318         usb_lock_device(udev);
 319         old_autosuspend_disabled = udev->autosuspend_disabled;
 320         old_autoresume_disabled = udev->autoresume_disabled;
 321
 322         /* Setting the flags without calling usb_pm_lock is a subject to
 323          * races, but who cares...
 324          */
 325         if (len == sizeof on_string - 1 &&
 326                         strncmp(buf, on_string, len) == 0) {
 327                 udev->autosuspend_disabled = 1;
 328                 udev->autoresume_disabled = 0;
 329                 rc = usb_external_resume_device(udev);
 330
 331         } else if (len == sizeof auto_string - 1 &&
 332                         strncmp(buf, auto_string, len) == 0) {
 333                 udev->autosuspend_disabled = 0;
 334                 udev->autoresume_disabled = 0;
 335                 rc = usb_external_resume_device(udev);
 336
 337         } else if (len == sizeof suspend_string - 1 &&
 338                         strncmp(buf, suspend_string, len) == 0) {
 339                 udev->autosuspend_disabled = 0;
 340                 udev->autoresume_disabled = 1;
 341                 rc = usb_external_suspend_device(udev, PMSG_SUSPEND);
 342
 343         } else
 344                 rc = -EINVAL;
 345
 346         if (rc) {
 347                 udev->autosuspend_disabled = old_autosuspend_disabled;
 348                 udev->autoresume_disabled = old_autoresume_disabled;
 349         }
 350         usb_unlock_device(udev);
 351         return (rc < 0 ? rc : count);
 352 }
 353
 354 static DEVICE_ATTR(level, S_IRUGO | S_IWUSR, show_level, set_level);
 355
 356 static int add_power_attributes(struct device *dev)
 357 {
 358         int rc = 0;
 359
 360         if (is_usb_device(dev)) {
 361                 rc = sysfs_add_file_to_group(&dev->kobj,
 362                                 &dev_attr_autosuspend.attr,
 363                                 power_group);
 364                 if (rc == 0)
 365                         rc = sysfs_add_file_to_group(&dev->kobj,
 366                                         &dev_attr_level.attr,
 367                                         power_group);
 368         }
 369         return rc;
 370 }
 371
 372 static void remove_power_attributes(struct device *dev)
 373 {
 374         sysfs_remove_file_from_group(&dev->kobj,
 375                         &dev_attr_level.attr,
 376                         power_group);
 377         sysfs_remove_file_from_group(&dev->kobj,
 378                         &dev_attr_autosuspend.attr,
 379                         power_group);
 380 }
 381
 382 #else
 383
 384 #define add_power_attributes(dev)       0
 385 #define remove_power_attributes(dev)    do {} while (0)
 386
 387 #endif  /* CONFIG_USB_SUSPEND */
 388
 389
 390 /* Descriptor fields */
 391 #define usb_descriptor_attr_le16(field, format_string)                  \
 392 static ssize_t                                                          \
 393 show_##field(struct device *dev, struct device_attribute *attr, \
 394                 char *buf)                                              \
 395 {                                                                       \
 396         struct usb_device *udev;                                        \
 397                                                                         \
 398         udev = to_usb_device(dev);                                      \
 399         return sprintf(buf, format_string,                              \
 400                         le16_to_cpu(udev->descriptor.field));           \
 401 }                                                                       \
 402 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
 403
 404 usb_descriptor_attr_le16(idVendor, "%04x\n")
 405 usb_descriptor_attr_le16(idProduct, "%04x\n")
 406 usb_descriptor_attr_le16(bcdDevice, "%04x\n")
 407
 408 #define usb_descriptor_attr(field, format_string)                       \
 409 static ssize_t                                                          \
 410 show_##field(struct device *dev, struct device_attribute *attr, \
 411                 char *buf)                                              \
 412 {                                                                       \
 413         struct usb_device *udev;                                        \
 414                                                                         \
 415         udev = to_usb_device(dev);                                      \
 416         return sprintf(buf, format_string, udev->descriptor.field);     \
 417 }                                                                       \
 418 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
 419
 420 usb_descriptor_attr(bDeviceClass, "%02x\n")
 421 usb_descriptor_attr(bDeviceSubClass, "%02x\n")
 422 usb_descriptor_attr(bDeviceProtocol, "%02x\n")
 423 usb_descriptor_attr(bNumConfigurations, "%d\n")
 424 usb_descriptor_attr(bMaxPacketSize0, "%d\n")
 425
 426
 427
 428 /* show if the device is authorized (1) or not (0) */
 429 static ssize_t usb_dev_authorized_show(struct device *dev,
 430                                        struct device_attribute *attr,
 431                                        char *buf)
 432 {
 433         struct usb_device *usb_dev = to_usb_device(dev);
 434         return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
 435 }
 436
 437
 438 /*
 439  * Authorize a device to be used in the system
 440  *
 441  * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
 442  */
 443 static ssize_t usb_dev_authorized_store(struct device *dev,
 444                                         struct device_attribute *attr,
 445                                         const char *buf, size_t size)
 446 {
 447         ssize_t result;
 448         struct usb_device *usb_dev = to_usb_device(dev);
 449         unsigned val;
 450         result = sscanf(buf, "%u\n", &val);
 451         if (result != 1)
 452                 result = -EINVAL;
 453         else if (val == 0)
 454                 result = usb_deauthorize_device(usb_dev);
 455         else
 456                 result = usb_authorize_device(usb_dev);
 457         return result < 0? result : size;
 458 }
 459
 460 static DEVICE_ATTR(authorized, 0644,
 461             usb_dev_authorized_show, usb_dev_authorized_store);
 462
 463
 464 static struct attribute *dev_attrs[] = {
 465         /* current configuration's attributes */
 466         &dev_attr_configuration.attr,
 467         &dev_attr_bNumInterfaces.attr,
 468         &dev_attr_bConfigurationValue.attr,
 469         &dev_attr_bmAttributes.attr,
 470         &dev_attr_bMaxPower.attr,
 471         &dev_attr_urbnum.attr,
 472         /* device attributes */
 473         &dev_attr_idVendor.attr,
 474         &dev_attr_idProduct.attr,
 475         &dev_attr_bcdDevice.attr,
 476         &dev_attr_bDeviceClass.attr,
 477         &dev_attr_bDeviceSubClass.attr,
 478         &dev_attr_bDeviceProtocol.attr,
 479         &dev_attr_bNumConfigurations.attr,
 480         &dev_attr_bMaxPacketSize0.attr,
 481         &dev_attr_speed.attr,
 482         &dev_attr_busnum.attr,
 483         &dev_attr_devnum.attr,
 484         &dev_attr_version.attr,
 485         &dev_attr_maxchild.attr,
 486         &dev_attr_quirks.attr,
 487         &dev_attr_authorized.attr,
 488         NULL,
 489 };
 490 static struct attribute_group dev_attr_grp = {
 491         .attrs = dev_attrs,
 492 };
 493
 494 /* Binary descriptors */
 495
 496 static ssize_t
 497 read_descriptors(struct kobject *kobj, struct bin_attribute *attr,
 498                 char *buf, loff_t off, size_t count)
 499 {
 500         struct usb_device *udev = to_usb_device(
 501                         container_of(kobj, struct device, kobj));
 502         size_t nleft = count;
 503         size_t srclen, n;
 504
 505         usb_lock_device(udev);
 506
 507         /* The binary attribute begins with the device descriptor */
 508         srclen = sizeof(struct usb_device_descriptor);
 509         if (off < srclen) {
 510                 n = min_t(size_t, nleft, srclen - off);
 511                 memcpy(buf, off + (char *) &udev->descriptor, n);
 512                 nleft -= n;
 513                 buf += n;
 514                 off = 0;
 515         } else {
 516                 off -= srclen;
 517         }
 518
 519         /* Then follows the raw descriptor entry for the current
 520          * configuration (config plus subsidiary descriptors).
 521          */
 522         if (udev->actconfig) {
 523                 int cfgno = udev->actconfig - udev->config;
 524
 525                 srclen = __le16_to_cpu(udev->actconfig->desc.wTotalLength);
 526                 if (off < srclen) {
 527                         n = min_t(size_t, nleft, srclen - off);
 528                         memcpy(buf, off + udev->rawdescriptors[cfgno], n);
 529                         nleft -= n;
 530                 }
 531         }
 532         usb_unlock_device(udev);
 533         return count - nleft;
 534 }
 535
 536 static struct bin_attribute dev_bin_attr_descriptors = {
 537         .attr = {.name = "descriptors", .mode = 0444},
 538         .read = read_descriptors,
 539         .size = 18 + 65535,     /* dev descr + max-size raw descriptor */
 540 };
 541
 542 int usb_create_sysfs_dev_files(struct usb_device *udev)
 543 {
 544         struct device *dev = &udev->dev;
 545         int retval;
 546
 547         retval = sysfs_create_group(&dev->kobj, &dev_attr_grp);
 548         if (retval)
 549                 return retval;
 550
 551         retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
 552         if (retval)
 553                 goto error;
 554
 555         retval = add_persist_attributes(dev);
 556         if (retval)
 557                 goto error;
 558
 559         retval = add_power_attributes(dev);
 560         if (retval)
 561                 goto error;
 562
 563         if (udev->manufacturer) {
 564                 retval = device_create_file(dev, &dev_attr_manufacturer);
 565                 if (retval)
 566                         goto error;
 567         }
 568         if (udev->product) {
 569                 retval = device_create_file(dev, &dev_attr_product);
 570                 if (retval)
 571                         goto error;
 572         }
 573         if (udev->serial) {
 574                 retval = device_create_file(dev, &dev_attr_serial);
 575                 if (retval)
 576                         goto error;
 577         }
 578         retval = usb_create_ep_files(dev, &udev->ep0, udev);
 579         if (retval)
 580                 goto error;
 581         return 0;
 582 error:
 583         usb_remove_sysfs_dev_files(udev);
 584         return retval;
 585 }
 586
 587 void usb_remove_sysfs_dev_files(struct usb_device *udev)
 588 {
 589         struct device *dev = &udev->dev;
 590
 591         usb_remove_ep_files(&udev->ep0);
 592         device_remove_file(dev, &dev_attr_manufacturer);
 593         device_remove_file(dev, &dev_attr_product);
 594         device_remove_file(dev, &dev_attr_serial);
 595         remove_power_attributes(dev);
 596         remove_persist_attributes(dev);
 597         device_remove_bin_file(dev, &dev_bin_attr_descriptors);
 598         sysfs_remove_group(&dev->kobj, &dev_attr_grp);
 599 }
 600
 601 /* Interface Accociation Descriptor fields */
 602 #define usb_intf_assoc_attr(field, format_string)                       \
 603 static ssize_t                                                          \
 604 show_iad_##field (struct device *dev, struct device_attribute *attr,    \
 605                 char *buf)                                              \
 606 {                                                                       \
 607         struct usb_interface *intf = to_usb_interface (dev);            \
 608                                                                         \
 609         return sprintf (buf, format_string,                             \
 610                         intf->intf_assoc->field);               \
 611 }                                                                       \
 612 static DEVICE_ATTR(iad_##field, S_IRUGO, show_iad_##field, NULL);
 613
 614 usb_intf_assoc_attr (bFirstInterface, "%02x\n")
 615 usb_intf_assoc_attr (bInterfaceCount, "%02d\n")
 616 usb_intf_assoc_attr (bFunctionClass, "%02x\n")
 617 usb_intf_assoc_attr (bFunctionSubClass, "%02x\n")
 618 usb_intf_assoc_attr (bFunctionProtocol, "%02x\n")
 619
 620 /* Interface fields */
 621 #define usb_intf_attr(field, format_string)                             \
 622 static ssize_t                                                          \
 623 show_##field(struct device *dev, struct device_attribute *attr, \
 624                 char *buf)                                              \
 625 {                                                                       \
 626         struct usb_interface *intf = to_usb_interface(dev);             \
 627                                                                         \
 628         return sprintf(buf, format_string,                              \
 629                         intf->cur_altsetting->desc.field);              \
 630 }                                                                       \
 631 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
 632
 633 usb_intf_attr(bInterfaceNumber, "%02x\n")
 634 usb_intf_attr(bAlternateSetting, "%2d\n")
 635 usb_intf_attr(bNumEndpoints, "%02x\n")
 636 usb_intf_attr(bInterfaceClass, "%02x\n")
 637 usb_intf_attr(bInterfaceSubClass, "%02x\n")
 638 usb_intf_attr(bInterfaceProtocol, "%02x\n")
 639
 640 static ssize_t show_interface_string(struct device *dev,
 641                 struct device_attribute *attr, char *buf)
 642 {
 643         struct usb_interface *intf;
 644         struct usb_device *udev;
 645         int len;
 646
 647         intf = to_usb_interface(dev);
 648         udev = interface_to_usbdev(intf);
 649         len = snprintf(buf, 256, "%s", intf->cur_altsetting->string);
 650         if (len < 0)
 651                 return 0;
 652         buf[len] = '\n';
 653         buf[len+1] = 0;
 654         return len+1;
 655 }
 656 static DEVICE_ATTR(interface, S_IRUGO, show_interface_string, NULL);
 657
 658 static ssize_t show_modalias(struct device *dev,
 659                 struct device_attribute *attr, char *buf)
 660 {
 661         struct usb_interface *intf;
 662         struct usb_device *udev;
 663         struct usb_host_interface *alt;
 664
 665         intf = to_usb_interface(dev);
 666         udev = interface_to_usbdev(intf);
 667         alt = intf->cur_altsetting;
 668
 669         return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
 670                         "ic%02Xisc%02Xip%02X\n",
 671                         le16_to_cpu(udev->descriptor.idVendor),
 672                         le16_to_cpu(udev->descriptor.idProduct),
 673                         le16_to_cpu(udev->descriptor.bcdDevice),
 674                         udev->descriptor.bDeviceClass,
 675                         udev->descriptor.bDeviceSubClass,
 676                         udev->descriptor.bDeviceProtocol,
 677                         alt->desc.bInterfaceClass,
 678                         alt->desc.bInterfaceSubClass,
 679                         alt->desc.bInterfaceProtocol);
 680 }
 681 static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL);
 682
 683 static struct attribute *intf_assoc_attrs[] = {
 684         &dev_attr_iad_bFirstInterface.attr,
 685         &dev_attr_iad_bInterfaceCount.attr,
 686         &dev_attr_iad_bFunctionClass.attr,
 687         &dev_attr_iad_bFunctionSubClass.attr,
 688         &dev_attr_iad_bFunctionProtocol.attr,
 689         NULL,
 690 };
 691 static struct attribute_group intf_assoc_attr_grp = {
 692         .attrs = intf_assoc_attrs,
 693 };
 694
 695 static struct attribute *intf_attrs[] = {
 696         &dev_attr_bInterfaceNumber.attr,
 697         &dev_attr_bAlternateSetting.attr,
 698         &dev_attr_bNumEndpoints.attr,
 699         &dev_attr_bInterfaceClass.attr,
 700         &dev_attr_bInterfaceSubClass.attr,
 701         &dev_attr_bInterfaceProtocol.attr,
 702         &dev_attr_modalias.attr,
 703         NULL,
 704 };
 705 static struct attribute_group intf_attr_grp = {
 706         .attrs = intf_attrs,
 707 };
 708
 709 static inline void usb_create_intf_ep_files(struct usb_interface *intf,
 710                 struct usb_device *udev)
 711 {
 712         struct usb_host_interface *iface_desc;
 713         int i;
 714
 715         iface_desc = intf->cur_altsetting;
 716         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i)
 717                 usb_create_ep_files(&intf->dev, &iface_desc->endpoint[i],
 718                                 udev);
 719 }
 720
 721 static inline void usb_remove_intf_ep_files(struct usb_interface *intf)
 722 {
 723         struct usb_host_interface *iface_desc;
 724         int i;
 725
 726         iface_desc = intf->cur_altsetting;
 727         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i)
 728                 usb_remove_ep_files(&iface_desc->endpoint[i]);
 729 }
 730
 731 int usb_create_sysfs_intf_files(struct usb_interface *intf)
 732 {
 733         struct device *dev = &intf->dev;
 734         struct usb_device *udev = interface_to_usbdev(intf);
 735         struct usb_host_interface *alt = intf->cur_altsetting;
 736         int retval;
 737
 738         if (intf->sysfs_files_created)
 739                 return 0;
 740         retval = sysfs_create_group(&dev->kobj, &intf_attr_grp);
 741         if (retval)
 742                 return retval;
 743
 744         if (alt->string == NULL)
 745                 alt->string = usb_cache_string(udev, alt->desc.iInterface);
 746         if (alt->string)
 747                 retval = device_create_file(dev, &dev_attr_interface);
 748         if (intf->intf_assoc)
 749                 retval = sysfs_create_group(&dev->kobj, &intf_assoc_attr_grp);
 750         usb_create_intf_ep_files(intf, udev);
 751         intf->sysfs_files_created = 1;
 752         return 0;
 753 }
 754
 755 void usb_remove_sysfs_intf_files(struct usb_interface *intf)
 756 {
 757         struct device *dev = &intf->dev;
 758
 759         if (!intf->sysfs_files_created)
 760                 return;
 761         usb_remove_intf_ep_files(intf);
 762         device_remove_file(dev, &dev_attr_interface);
 763         sysfs_remove_group(&dev->kobj, &intf_attr_grp);
 764         sysfs_remove_group(&intf->dev.kobj, &intf_assoc_attr_grp);
 765         intf->sysfs_files_created = 0;
 766 }