2 * drivers/usb/core/sysfs.c
4 * (C) Copyright 2002 David Brownell
5 * (C) Copyright 2002,2004 Greg Kroah-Hartman
6 * (C) Copyright 2002,2004 IBM Corp.
8 * All of the sysfs file attributes for usb devices and interfaces.
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/usb.h>
16 #include <linux/usb/quirks.h>
19 /* Active configuration fields */
20 #define usb_actconfig_show(field, multiplier, format_string) \
21 static ssize_t show_##field(struct device *dev, \
22 struct device_attribute *attr, char *buf) \
24 struct usb_device *udev; \
25 struct usb_host_config *actconfig; \
27 udev = to_usb_device(dev); \
28 actconfig = udev->actconfig; \
30 return sprintf(buf, format_string, \
31 actconfig->desc.field * multiplier); \
36 #define usb_actconfig_attr(field, multiplier, format_string) \
37 usb_actconfig_show(field, multiplier, format_string) \
38 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
40 usb_actconfig_attr(bNumInterfaces, 1, "%2d\n")
41 usb_actconfig_attr(bmAttributes, 1, "%2x\n")
42 usb_actconfig_attr(bMaxPower, 2, "%3dmA\n")
44 static ssize_t show_configuration_string(struct device *dev,
45 struct device_attribute *attr, char *buf)
47 struct usb_device *udev;
48 struct usb_host_config *actconfig;
50 udev = to_usb_device(dev);
51 actconfig = udev->actconfig;
52 if ((!actconfig) || (!actconfig->string))
54 return sprintf(buf, "%s\n", actconfig->string);
56 static DEVICE_ATTR(configuration, S_IRUGO, show_configuration_string, NULL);
58 /* configuration value is always present, and r/w */
59 usb_actconfig_show(bConfigurationValue, 1, "%u\n");
62 set_bConfigurationValue(struct device *dev, struct device_attribute *attr,
63 const char *buf, size_t count)
65 struct usb_device *udev = to_usb_device(dev);
68 if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
70 usb_lock_device(udev);
71 value = usb_set_configuration(udev, config);
72 usb_unlock_device(udev);
73 return (value < 0) ? value : count;
76 static DEVICE_ATTR(bConfigurationValue, S_IRUGO | S_IWUSR,
77 show_bConfigurationValue, set_bConfigurationValue);
80 #define usb_string_attr(name) \
81 static ssize_t show_##name(struct device *dev, \
82 struct device_attribute *attr, char *buf) \
84 struct usb_device *udev; \
87 udev = to_usb_device(dev); \
88 usb_lock_device(udev); \
89 retval = sprintf(buf, "%s\n", udev->name); \
90 usb_unlock_device(udev); \
93 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
95 usb_string_attr(product);
96 usb_string_attr(manufacturer);
97 usb_string_attr(serial);
100 show_speed(struct device *dev, struct device_attribute *attr, char *buf)
102 struct usb_device *udev;
105 udev = to_usb_device(dev);
107 switch (udev->speed) {
111 case USB_SPEED_UNKNOWN:
118 case USB_SPEED_WIRELESS:
121 case USB_SPEED_SUPER:
127 return sprintf(buf, "%s\n", speed);
129 static DEVICE_ATTR(speed, S_IRUGO, show_speed, NULL);
132 show_busnum(struct device *dev, struct device_attribute *attr, char *buf)
134 struct usb_device *udev;
136 udev = to_usb_device(dev);
137 return sprintf(buf, "%d\n", udev->bus->busnum);
139 static DEVICE_ATTR(busnum, S_IRUGO, show_busnum, NULL);
142 show_devnum(struct device *dev, struct device_attribute *attr, char *buf)
144 struct usb_device *udev;
146 udev = to_usb_device(dev);
147 return sprintf(buf, "%d\n", udev->devnum);
149 static DEVICE_ATTR(devnum, S_IRUGO, show_devnum, NULL);
152 show_devpath(struct device *dev, struct device_attribute *attr, char *buf)
154 struct usb_device *udev;
156 udev = to_usb_device(dev);
157 return sprintf(buf, "%s\n", udev->devpath);
159 static DEVICE_ATTR(devpath, S_IRUGO, show_devpath, NULL);
162 show_version(struct device *dev, struct device_attribute *attr, char *buf)
164 struct usb_device *udev;
167 udev = to_usb_device(dev);
168 bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
169 return sprintf(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
171 static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
174 show_maxchild(struct device *dev, struct device_attribute *attr, char *buf)
176 struct usb_device *udev;
178 udev = to_usb_device(dev);
179 return sprintf(buf, "%d\n", udev->maxchild);
181 static DEVICE_ATTR(maxchild, S_IRUGO, show_maxchild, NULL);
184 show_quirks(struct device *dev, struct device_attribute *attr, char *buf)
186 struct usb_device *udev;
188 udev = to_usb_device(dev);
189 return sprintf(buf, "0x%x\n", udev->quirks);
191 static DEVICE_ATTR(quirks, S_IRUGO, show_quirks, NULL);
194 show_avoid_reset_quirk(struct device *dev, struct device_attribute *attr, char *buf)
196 struct usb_device *udev;
198 udev = to_usb_device(dev);
199 return sprintf(buf, "%d\n", !!(udev->quirks & USB_QUIRK_RESET_MORPHS));
203 set_avoid_reset_quirk(struct device *dev, struct device_attribute *attr,
204 const char *buf, size_t count)
206 struct usb_device *udev = to_usb_device(dev);
209 if (sscanf(buf, "%d", &config) != 1 || config < 0 || config > 1)
211 usb_lock_device(udev);
213 udev->quirks |= USB_QUIRK_RESET_MORPHS;
215 udev->quirks &= ~USB_QUIRK_RESET_MORPHS;
216 usb_unlock_device(udev);
220 static DEVICE_ATTR(avoid_reset_quirk, S_IRUGO | S_IWUSR,
221 show_avoid_reset_quirk, set_avoid_reset_quirk);
224 show_urbnum(struct device *dev, struct device_attribute *attr, char *buf)
226 struct usb_device *udev;
228 udev = to_usb_device(dev);
229 return sprintf(buf, "%d\n", atomic_read(&udev->urbnum));
231 static DEVICE_ATTR(urbnum, S_IRUGO, show_urbnum, NULL);
236 static const char power_group[] = "power";
239 show_persist(struct device *dev, struct device_attribute *attr, char *buf)
241 struct usb_device *udev = to_usb_device(dev);
243 return sprintf(buf, "%d\n", udev->persist_enabled);
247 set_persist(struct device *dev, struct device_attribute *attr,
248 const char *buf, size_t count)
250 struct usb_device *udev = to_usb_device(dev);
253 /* Hubs are always enabled for USB_PERSIST */
254 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
257 if (sscanf(buf, "%d", &value) != 1)
260 usb_lock_device(udev);
261 udev->persist_enabled = !!value;
262 usb_unlock_device(udev);
266 static DEVICE_ATTR(persist, S_IRUGO | S_IWUSR, show_persist, set_persist);
268 static int add_persist_attributes(struct device *dev)
272 if (is_usb_device(dev)) {
273 struct usb_device *udev = to_usb_device(dev);
275 /* Hubs are automatically enabled for USB_PERSIST,
276 * no point in creating the attribute file.
278 if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
279 rc = sysfs_add_file_to_group(&dev->kobj,
280 &dev_attr_persist.attr,
286 static void remove_persist_attributes(struct device *dev)
288 sysfs_remove_file_from_group(&dev->kobj,
289 &dev_attr_persist.attr,
294 #define add_persist_attributes(dev) 0
295 #define remove_persist_attributes(dev) do {} while (0)
297 #endif /* CONFIG_PM */
299 #ifdef CONFIG_USB_SUSPEND
302 show_connected_duration(struct device *dev, struct device_attribute *attr,
305 struct usb_device *udev = to_usb_device(dev);
307 return sprintf(buf, "%u\n",
308 jiffies_to_msecs(jiffies - udev->connect_time));
311 static DEVICE_ATTR(connected_duration, S_IRUGO, show_connected_duration, NULL);
314 * If the device is resumed, the last time the device was suspended has
315 * been pre-subtracted from active_duration. We add the current time to
316 * get the duration that the device was actually active.
318 * If the device is suspended, the active_duration is up-to-date.
321 show_active_duration(struct device *dev, struct device_attribute *attr,
324 struct usb_device *udev = to_usb_device(dev);
327 if (udev->state != USB_STATE_SUSPENDED)
328 duration = jiffies_to_msecs(jiffies + udev->active_duration);
330 duration = jiffies_to_msecs(udev->active_duration);
331 return sprintf(buf, "%u\n", duration);
334 static DEVICE_ATTR(active_duration, S_IRUGO, show_active_duration, NULL);
337 show_autosuspend(struct device *dev, struct device_attribute *attr, char *buf)
339 struct usb_device *udev = to_usb_device(dev);
341 return sprintf(buf, "%d\n", udev->autosuspend_delay / HZ);
345 set_autosuspend(struct device *dev, struct device_attribute *attr,
346 const char *buf, size_t count)
348 struct usb_device *udev = to_usb_device(dev);
349 int value, old_delay;
352 if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/HZ ||
353 value <= - INT_MAX/HZ)
357 usb_lock_device(udev);
358 old_delay = udev->autosuspend_delay;
359 udev->autosuspend_delay = value;
361 if (old_delay < 0) { /* Autosuspend wasn't allowed */
363 usb_autosuspend_device(udev);
364 } else { /* Autosuspend was allowed */
366 rc = usb_autoresume_device(udev);
369 udev->autosuspend_delay = old_delay;
372 usb_try_autosuspend_device(udev);
376 usb_unlock_device(udev);
380 static DEVICE_ATTR(autosuspend, S_IRUGO | S_IWUSR,
381 show_autosuspend, set_autosuspend);
383 static const char on_string[] = "on";
384 static const char auto_string[] = "auto";
387 show_level(struct device *dev, struct device_attribute *attr, char *buf)
389 struct usb_device *udev = to_usb_device(dev);
390 const char *p = auto_string;
392 if (udev->state != USB_STATE_SUSPENDED && udev->autosuspend_disabled)
394 return sprintf(buf, "%s\n", p);
398 set_level(struct device *dev, struct device_attribute *attr,
399 const char *buf, size_t count)
401 struct usb_device *udev = to_usb_device(dev);
406 cp = memchr(buf, '\n', count);
410 usb_lock_device(udev);
412 if (len == sizeof on_string - 1 &&
413 strncmp(buf, on_string, len) == 0)
414 rc = usb_disable_autosuspend(udev);
416 else if (len == sizeof auto_string - 1 &&
417 strncmp(buf, auto_string, len) == 0)
418 rc = usb_enable_autosuspend(udev);
423 usb_unlock_device(udev);
424 return (rc < 0 ? rc : count);
427 static DEVICE_ATTR(level, S_IRUGO | S_IWUSR, show_level, set_level);
429 static int add_power_attributes(struct device *dev)
433 if (is_usb_device(dev)) {
434 rc = sysfs_add_file_to_group(&dev->kobj,
435 &dev_attr_autosuspend.attr,
438 rc = sysfs_add_file_to_group(&dev->kobj,
439 &dev_attr_level.attr,
442 rc = sysfs_add_file_to_group(&dev->kobj,
443 &dev_attr_connected_duration.attr,
446 rc = sysfs_add_file_to_group(&dev->kobj,
447 &dev_attr_active_duration.attr,
453 static void remove_power_attributes(struct device *dev)
455 sysfs_remove_file_from_group(&dev->kobj,
456 &dev_attr_active_duration.attr,
458 sysfs_remove_file_from_group(&dev->kobj,
459 &dev_attr_connected_duration.attr,
461 sysfs_remove_file_from_group(&dev->kobj,
462 &dev_attr_level.attr,
464 sysfs_remove_file_from_group(&dev->kobj,
465 &dev_attr_autosuspend.attr,
471 #define add_power_attributes(dev) 0
472 #define remove_power_attributes(dev) do {} while (0)
474 #endif /* CONFIG_USB_SUSPEND */
477 /* Descriptor fields */
478 #define usb_descriptor_attr_le16(field, format_string) \
480 show_##field(struct device *dev, struct device_attribute *attr, \
483 struct usb_device *udev; \
485 udev = to_usb_device(dev); \
486 return sprintf(buf, format_string, \
487 le16_to_cpu(udev->descriptor.field)); \
489 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
491 usb_descriptor_attr_le16(idVendor, "%04x\n")
492 usb_descriptor_attr_le16(idProduct, "%04x\n")
493 usb_descriptor_attr_le16(bcdDevice, "%04x\n")
495 #define usb_descriptor_attr(field, format_string) \
497 show_##field(struct device *dev, struct device_attribute *attr, \
500 struct usb_device *udev; \
502 udev = to_usb_device(dev); \
503 return sprintf(buf, format_string, udev->descriptor.field); \
505 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
507 usb_descriptor_attr(bDeviceClass, "%02x\n")
508 usb_descriptor_attr(bDeviceSubClass, "%02x\n")
509 usb_descriptor_attr(bDeviceProtocol, "%02x\n")
510 usb_descriptor_attr(bNumConfigurations, "%d\n")
511 usb_descriptor_attr(bMaxPacketSize0, "%d\n")
515 /* show if the device is authorized (1) or not (0) */
516 static ssize_t usb_dev_authorized_show(struct device *dev,
517 struct device_attribute *attr,
520 struct usb_device *usb_dev = to_usb_device(dev);
521 return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
526 * Authorize a device to be used in the system
528 * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
530 static ssize_t usb_dev_authorized_store(struct device *dev,
531 struct device_attribute *attr,
532 const char *buf, size_t size)
535 struct usb_device *usb_dev = to_usb_device(dev);
537 result = sscanf(buf, "%u\n", &val);
541 result = usb_deauthorize_device(usb_dev);
543 result = usb_authorize_device(usb_dev);
544 return result < 0? result : size;
547 static DEVICE_ATTR(authorized, 0644,
548 usb_dev_authorized_show, usb_dev_authorized_store);
550 /* "Safely remove a device" */
551 static ssize_t usb_remove_store(struct device *dev,
552 struct device_attribute *attr,
553 const char *buf, size_t count)
555 struct usb_device *udev = to_usb_device(dev);
558 usb_lock_device(udev);
559 if (udev->state != USB_STATE_NOTATTACHED) {
561 /* To avoid races, first unconfigure and then remove */
562 usb_set_configuration(udev, -1);
563 rc = usb_remove_device(udev);
567 usb_unlock_device(udev);
570 static DEVICE_ATTR(remove, 0200, NULL, usb_remove_store);
573 static struct attribute *dev_attrs[] = {
574 /* current configuration's attributes */
575 &dev_attr_configuration.attr,
576 &dev_attr_bNumInterfaces.attr,
577 &dev_attr_bConfigurationValue.attr,
578 &dev_attr_bmAttributes.attr,
579 &dev_attr_bMaxPower.attr,
580 /* device attributes */
581 &dev_attr_urbnum.attr,
582 &dev_attr_idVendor.attr,
583 &dev_attr_idProduct.attr,
584 &dev_attr_bcdDevice.attr,
585 &dev_attr_bDeviceClass.attr,
586 &dev_attr_bDeviceSubClass.attr,
587 &dev_attr_bDeviceProtocol.attr,
588 &dev_attr_bNumConfigurations.attr,
589 &dev_attr_bMaxPacketSize0.attr,
590 &dev_attr_speed.attr,
591 &dev_attr_busnum.attr,
592 &dev_attr_devnum.attr,
593 &dev_attr_devpath.attr,
594 &dev_attr_version.attr,
595 &dev_attr_maxchild.attr,
596 &dev_attr_quirks.attr,
597 &dev_attr_avoid_reset_quirk.attr,
598 &dev_attr_authorized.attr,
599 &dev_attr_remove.attr,
602 static struct attribute_group dev_attr_grp = {
606 /* When modifying this list, be sure to modify dev_string_attrs_are_visible()
609 static struct attribute *dev_string_attrs[] = {
610 &dev_attr_manufacturer.attr,
611 &dev_attr_product.attr,
612 &dev_attr_serial.attr,
616 static mode_t dev_string_attrs_are_visible(struct kobject *kobj,
617 struct attribute *a, int n)
619 struct device *dev = container_of(kobj, struct device, kobj);
620 struct usb_device *udev = to_usb_device(dev);
622 if (a == &dev_attr_manufacturer.attr) {
623 if (udev->manufacturer == NULL)
625 } else if (a == &dev_attr_product.attr) {
626 if (udev->product == NULL)
628 } else if (a == &dev_attr_serial.attr) {
629 if (udev->serial == NULL)
635 static struct attribute_group dev_string_attr_grp = {
636 .attrs = dev_string_attrs,
637 .is_visible = dev_string_attrs_are_visible,
640 const struct attribute_group *usb_device_groups[] = {
642 &dev_string_attr_grp,
646 /* Binary descriptors */
649 read_descriptors(struct kobject *kobj, struct bin_attribute *attr,
650 char *buf, loff_t off, size_t count)
652 struct device *dev = container_of(kobj, struct device, kobj);
653 struct usb_device *udev = to_usb_device(dev);
654 size_t nleft = count;
659 /* The binary attribute begins with the device descriptor.
660 * Following that are the raw descriptor entries for all the
661 * configurations (config plus subsidiary descriptors).
663 for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
664 nleft > 0; ++cfgno) {
666 src = &udev->descriptor;
667 srclen = sizeof(struct usb_device_descriptor);
669 src = udev->rawdescriptors[cfgno];
670 srclen = __le16_to_cpu(udev->config[cfgno].desc.
674 n = min(nleft, srclen - (size_t) off);
675 memcpy(buf, src + off, n);
683 return count - nleft;
686 static struct bin_attribute dev_bin_attr_descriptors = {
687 .attr = {.name = "descriptors", .mode = 0444},
688 .read = read_descriptors,
689 .size = 18 + 65535, /* dev descr + max-size raw descriptor */
692 int usb_create_sysfs_dev_files(struct usb_device *udev)
694 struct device *dev = &udev->dev;
697 retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
701 retval = add_persist_attributes(dev);
705 retval = add_power_attributes(dev);
710 usb_remove_sysfs_dev_files(udev);
714 void usb_remove_sysfs_dev_files(struct usb_device *udev)
716 struct device *dev = &udev->dev;
718 remove_power_attributes(dev);
719 remove_persist_attributes(dev);
720 device_remove_bin_file(dev, &dev_bin_attr_descriptors);
723 /* Interface Accociation Descriptor fields */
724 #define usb_intf_assoc_attr(field, format_string) \
726 show_iad_##field(struct device *dev, struct device_attribute *attr, \
729 struct usb_interface *intf = to_usb_interface(dev); \
731 return sprintf(buf, format_string, \
732 intf->intf_assoc->field); \
734 static DEVICE_ATTR(iad_##field, S_IRUGO, show_iad_##field, NULL);
736 usb_intf_assoc_attr(bFirstInterface, "%02x\n")
737 usb_intf_assoc_attr(bInterfaceCount, "%02d\n")
738 usb_intf_assoc_attr(bFunctionClass, "%02x\n")
739 usb_intf_assoc_attr(bFunctionSubClass, "%02x\n")
740 usb_intf_assoc_attr(bFunctionProtocol, "%02x\n")
742 /* Interface fields */
743 #define usb_intf_attr(field, format_string) \
745 show_##field(struct device *dev, struct device_attribute *attr, \
748 struct usb_interface *intf = to_usb_interface(dev); \
750 return sprintf(buf, format_string, \
751 intf->cur_altsetting->desc.field); \
753 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
755 usb_intf_attr(bInterfaceNumber, "%02x\n")
756 usb_intf_attr(bAlternateSetting, "%2d\n")
757 usb_intf_attr(bNumEndpoints, "%02x\n")
758 usb_intf_attr(bInterfaceClass, "%02x\n")
759 usb_intf_attr(bInterfaceSubClass, "%02x\n")
760 usb_intf_attr(bInterfaceProtocol, "%02x\n")
762 static ssize_t show_interface_string(struct device *dev,
763 struct device_attribute *attr, char *buf)
765 struct usb_interface *intf;
768 intf = to_usb_interface(dev);
769 string = intf->cur_altsetting->string;
770 barrier(); /* The altsetting might change! */
774 return sprintf(buf, "%s\n", string);
776 static DEVICE_ATTR(interface, S_IRUGO, show_interface_string, NULL);
778 static ssize_t show_modalias(struct device *dev,
779 struct device_attribute *attr, char *buf)
781 struct usb_interface *intf;
782 struct usb_device *udev;
783 struct usb_host_interface *alt;
785 intf = to_usb_interface(dev);
786 udev = interface_to_usbdev(intf);
787 alt = intf->cur_altsetting;
789 return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
790 "ic%02Xisc%02Xip%02X\n",
791 le16_to_cpu(udev->descriptor.idVendor),
792 le16_to_cpu(udev->descriptor.idProduct),
793 le16_to_cpu(udev->descriptor.bcdDevice),
794 udev->descriptor.bDeviceClass,
795 udev->descriptor.bDeviceSubClass,
796 udev->descriptor.bDeviceProtocol,
797 alt->desc.bInterfaceClass,
798 alt->desc.bInterfaceSubClass,
799 alt->desc.bInterfaceProtocol);
801 static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL);
803 static ssize_t show_supports_autosuspend(struct device *dev,
804 struct device_attribute *attr, char *buf)
806 struct usb_interface *intf;
807 struct usb_device *udev;
810 intf = to_usb_interface(dev);
811 udev = interface_to_usbdev(intf);
813 usb_lock_device(udev);
814 /* Devices will be autosuspended even when an interface isn't claimed */
815 if (!intf->dev.driver ||
816 to_usb_driver(intf->dev.driver)->supports_autosuspend)
817 ret = sprintf(buf, "%u\n", 1);
819 ret = sprintf(buf, "%u\n", 0);
820 usb_unlock_device(udev);
824 static DEVICE_ATTR(supports_autosuspend, S_IRUGO, show_supports_autosuspend, NULL);
826 static struct attribute *intf_attrs[] = {
827 &dev_attr_bInterfaceNumber.attr,
828 &dev_attr_bAlternateSetting.attr,
829 &dev_attr_bNumEndpoints.attr,
830 &dev_attr_bInterfaceClass.attr,
831 &dev_attr_bInterfaceSubClass.attr,
832 &dev_attr_bInterfaceProtocol.attr,
833 &dev_attr_modalias.attr,
834 &dev_attr_supports_autosuspend.attr,
837 static struct attribute_group intf_attr_grp = {
841 static struct attribute *intf_assoc_attrs[] = {
842 &dev_attr_iad_bFirstInterface.attr,
843 &dev_attr_iad_bInterfaceCount.attr,
844 &dev_attr_iad_bFunctionClass.attr,
845 &dev_attr_iad_bFunctionSubClass.attr,
846 &dev_attr_iad_bFunctionProtocol.attr,
850 static mode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
851 struct attribute *a, int n)
853 struct device *dev = container_of(kobj, struct device, kobj);
854 struct usb_interface *intf = to_usb_interface(dev);
856 if (intf->intf_assoc == NULL)
861 static struct attribute_group intf_assoc_attr_grp = {
862 .attrs = intf_assoc_attrs,
863 .is_visible = intf_assoc_attrs_are_visible,
866 const struct attribute_group *usb_interface_groups[] = {
868 &intf_assoc_attr_grp,
872 int usb_create_sysfs_intf_files(struct usb_interface *intf)
874 struct usb_device *udev = interface_to_usbdev(intf);
875 struct usb_host_interface *alt = intf->cur_altsetting;
878 if (intf->sysfs_files_created || intf->unregistering)
881 if (alt->string == NULL &&
882 !(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
883 alt->string = usb_cache_string(udev, alt->desc.iInterface);
885 retval = device_create_file(&intf->dev, &dev_attr_interface);
886 intf->sysfs_files_created = 1;
890 void usb_remove_sysfs_intf_files(struct usb_interface *intf)
892 if (!intf->sysfs_files_created)
895 device_remove_file(&intf->dev, &dev_attr_interface);
896 intf->sysfs_files_created = 0;