1 What: /sys/bus/usb/devices/<INTERFAC
2 Date: August 2015
3 Description:
4 This allows to authorize (1) o
5 individual interfaces instead
6 in contrast to the device auth
7 If a deauthorized interface wi
8 so the driver probing must be
9 by writing INTERFACE to /sys/b
10 This allows to avoid side-effe
11 that need multiple interfaces.
12
13 A deauthorized interface canno
14
15 What: /sys/bus/usb/devices/usbX/inte
16 Date: August 2015
17 Description:
18 This is used as value that det
19 would be authorized by default
20 The value can be 1 or 0. It's
21
22 What: /sys/bus/usb/device/.../author
23 Date: July 2008
24 KernelVersion: 2.6.26
25 Contact: David Vrabel <david.vrabel@csr.
26 Description:
27 Authorized devices are availab
28 drivers, non-authorized one ar
29 USB devices are authorized.
30
31 What: /sys/bus/usb/drivers/.../new_i
32 Date: October 2011
33 Contact: linux-usb@vger.kernel.org
34 Description:
35 Writing a device ID to this fi
36 dynamically add a new device I
37 This may allow the driver to s
38 was included in the driver's s
39 table at compile time. The for
40 idVendor idProduct bInterfaceC
41 The vendor ID and device ID fi
42 rest is optional. The `Ref*` t
43 driver to use the same driver_
44 it is used for the reference d
45 Upon successfully adding an ID
46 for the device and attempt to
47
48 # echo "8086 10f5" > /sys/bu
49
50 Here add a new device (0458:70
51 an already supported device (0
52
53 # echo "0458 7045 0 0458 704
54
55 Reading from this file will li
56 device IDs in the same format,
57 line. For example::
58
59 # cat /sys/bus/usb/drivers/f
60 8086 10f5
61 dead beef 06
62 f00d cafe
63
64 The list will be truncated at
65 sysfs restrictions.
66
67 What: /sys/bus/usb-serial/drivers/..
68 Date: October 2011
69 Contact: linux-usb@vger.kernel.org
70 Description:
71 For serial USB drivers, this a
72 extra bus folder "usb-serial"
73 difference, all descriptions f
74 "/sys/bus/usb/drivers/.../new_
75
76 What: /sys/bus/usb/drivers/.../remov
77 Date: November 2009
78 Contact: CHENG Renquan <rqcheng@smu.edu.
79 Description:
80 Writing a device ID to this fi
81 that was dynamically added via
82 The format for the device ID i
83 idVendor idProduct. After
84 removing an ID, the driver wil
85 device. This is useful to ens
86 match the driver to the device
87 # echo "046d c315" > /sys/bus/
88
89 Reading from this file will li
90 device IDs, exactly like readi
91 "/sys/bus/usb/drivers/.../new_
92
93 What: /sys/bus/usb/devices/.../power
94 Date: September 2011
95 Contact: Andiry Xu <andiry.xu@amd.com>
96 Description:
97 If CONFIG_PM is set and a USB
98 in to a xHCI host which suppor
99 test; if the test is passed an
100 (xHCI 1.0 feature), USB2 hardw
101 device and the USB device dire
102 power/usb2_hardware_lpm. The
103 or disable) indicating whether
104 enabled for the device. Develo
105 the file to enable/disable the
106
107 What: /sys/bus/usb/devices/.../power
108 /sys/bus/usb/devices/.../power
109 Date: November 2015
110 Contact: Kevin Strasser <kevin.strasser@
111 Lu Baolu <baolu.lu@linux.intel.
112 Description:
113 If CONFIG_PM is set and a USB
114 in to a xHCI host which suppor
115 and U2 exit latencies have bee
116 the check is passed and the ho
117 USB3 hardware LPM will be enab
118 device directory will contain
119 power/usb3_hardware_lpm_u1 and
120 files hold a string value (ena
121 or not USB3 hardware LPM U1 or
122
123 What: /sys/bus/usb/devices/.../ltm_c
124 Date: July 2012
125 Contact: Sarah Sharp <sarah.a.sharp@linu
126 Description:
127 USB 3.0 devices may optionally
128 Messaging (LTM). They indicat
129 in the bmAttributes field of t
130 If that bit is set for the dev
131 If the device doesn't support
132 The file will be present for a
133 always read "no" for USB 1.1 a
134
135 What: /sys/bus/usb/devices/<INTERFAC
136 Date: February 2023
137 Contact: Bastien Nocera <hadess@hadess.n
138 Description:
139 Some USB devices use a USB rec
140 wirelessly with their device u
141 attribute allows user-space to
142 connected to its receiver dong
143 the device to be absent when c
144 device's battery, show a heads
145 an on-screen keyboard if the o
146 turned off.
147 This attribute is not to be us
148 statuses available in WWAN, WL
149 If the device does not use a r
150 device, then this attribute wi
151
152 What: /sys/bus/usb/devices/.../<hub_
153 Date: August 2012
154 Contact: Lan Tianyu <tianyu.lan@intel.co
155 Description:
156 The /sys/bus/usb/devices/.../<
157 is usb port device's sysfs dir
158
159 What: /sys/bus/usb/devices/.../<hub_
160 Date: January 2013
161 Contact: Lan Tianyu <tianyu.lan@intel.co
162 Description:
163 Some platforms provide usb por
164 This attribute is to expose th
165 The file will read "hotplug",
166 information is available, and
167
168 What: /sys/bus/usb/devices/.../<hub_
169 Date: October 2018
170 Contact: Bjørn Mork <bjorn@mork.no>
171 Description:
172 Some platforms provide usb por
173 firmware. This is used by the
174 mapping to the same physical c
175 raw location value as a hex in
176
177
178 What: /sys/bus/usb/devices/.../<hub_
179 Date: May 2018
180 Contact: Nicolas Boichat <drinkcat@chrom
181 Description:
182 In some cases, we care about t
183 connected on a specific port (
184 pogo pins), where the device t
185 advance, and behaves well acco
186 This attribute is a bit-field
187 a specific port:
188
189 - Bit 0 of this field selects
190 as it is considerably faste
191 instead of 2).
192
193 The old enumeration scheme
194 using /sys/module/usbcore/p
195 it is often not desirable a
196 increase compatibility with
197 - Bit 1 reduces TRSTRCY to th
198 USB 2.0 specification, inst
199 used to help make enumerati
200 devices.
201
202 What: /sys/bus/usb/devices/.../<hub_
203 Date: February 2018
204 Contact: Richard Leitner <richard.leitne
205 Description:
206 Most hubs are able to detect o
207 ports and report them to the k
208 the number of over-current sit
209 to user space. This file will
210 which wraps to 0 after its max
211 poll() for monitoring changes
212
213 Any time this value changes th
214 udev event with the following
215
216 OVER_CURRENT_PORT=/sys/bus/u
217 OVER_CURRENT_COUNT=[current
218
219 What: /sys/bus/usb/devices/.../<hub_
220 Date: November 2015
221 Contact: Lu Baolu <baolu.lu@linux.intel.
222 Description:
223 Some USB3.0 devices are not fr
224 attribute allows enabling/disa
225 effect both before and after a
226 values are "0" if both u1 and
227 is permitted, "u2" if only u2
228 u2 are permitted.
229
230 What: /sys/bus/usb/devices/.../<hub_
231 Date: December 2021
232 Contact: Heikki Krogerus <heikki.krogeru
233 Description:
234 Link to the USB Type-C connect
235 only created when USB Type-C C
236 only if the system firmware is
237 connection between a port and
238
239 What: /sys/bus/usb/devices/.../<hub_
240 Date: June 2022
241 Contact: Michael Grzeschik <m.grzeschik@
242 Description:
243 This file controls the state o
244 Vbus power output (but only on
245 power switching -- most hubs d
246 a port is disabled, the port i
247 attached to the port will not
248 or enumerated.
249
250 What: /sys/bus/usb/devices/.../<hub_
251 Date: Sep 2022
252 Contact: Ray Chi <raychi@google.com>
253 Description:
254 Some USB hosts have some watch
255 may enter ramdump if it takes
256 This attribute allows each por
257 port initialization will be fa
258 which is marked with early_sto
259 all future connections until t
260
261 What: /sys/bus/usb/devices/.../<hub_
262 Date: June 2023
263 Contact: Roy Luo <royluo@google.com>
264 Description:
265 Indicates current state of the
266 Valid states are: 'not-attache
267 'reconnecting', 'unauthenticat
268 'configured', and 'suspended'.
269 monitor the state change from
270
271 What: /sys/bus/usb/devices/.../power
272 Date: May 2013
273 Contact: Mathias Nyman <mathias.nyman@li
274 Description:
275 USB 2.0 devices may support ha
276 L1 sleep state. The usb2_lpm_l
277 tuning the timeout for L1 inac
278 needed inactivity time before
279 Useful for power management tu
280 Supported values are 0 - 65535
281
282 What: /sys/bus/usb/devices/.../power
283 Date: May 2013
284 Contact: Mathias Nyman <mathias.nyman@li
285 Description:
286 USB 2.0 devices that support h
287 L1 sleep state now use a best
288 indicate the best effort to re
289 initiation of the resume event
290 If the device does not have a
291 one instead. This usb2_lpm_bes
292 value in order to tune power s
293
294 Supported values are 0 - 15.
295 More information on how besl v
296 USB 2.0 ECN Errata for Link Po
297
298 What: /sys/bus/usb/devices/.../rx_la
299 Date: March 2018
300 Contact: Mathias Nyman <mathias.nyman@li
301 Description:
302 Number of rx lanes the device
303 USB 3.2 adds Dual-lane support
304 Inter-Chip SSIC devices suppor
305 direction. Devices before USB
306
307 What: /sys/bus/usb/devices/.../tx_la
308 Date: March 2018
309 Contact: Mathias Nyman <mathias.nyman@li
310 Description:
311 Number of tx lanes the device
312 USB 3.2 adds Dual-lane support
313 Inter-Chip SSIC devices suppor
314 direction. Devices before USB
315
316 What: /sys/bus/usb/devices/.../typec
317 Date: November 2023
318 Contact: Heikki Krogerus <heikki.krogeru
319 Description:
320 Symlink to the USB Type-C part
321 represents the component that
322 Configuration Channel (CC sign
323 cables) with the local port.
324
325 What: /sys/bus/usb/devices/usbX/bAlt
326 Description:
327 The current interface alternat
328
329 See USB specs for its meaning.
330
331 What: /sys/bus/usb/devices/usbX/bcdD
332 Description:
333 The device's release number, i
334
335 See USB specs for its meaning.
336
337 What: /sys/bus/usb/devices/usbX/bCon
338 Description:
339 While a USB device typically h
340 setting, some devices support
341
342 This value shows the current c
343
344 Changing its value will change
345 to another setting.
346
347 The number of configurations s
348
349 /sys/bus/usb/devices/u
350
351 See USB specs for its meaning.
352
353 What: /sys/bus/usb/devices/usbX/bDev
354 Description:
355 Class code of the device, in h
356
357 See USB specs for its meaning.
358
359 What: /sys/bus/usb/devices/usbX/bDev
360 Description:
361 Protocol code of the device, i
362
363 See USB specs for its meaning.
364
365 What: /sys/bus/usb/devices/usbX/bDev
366 Description:
367 Subclass code of the device, i
368
369 See USB specs for its meaning.
370
371 What: /sys/bus/usb/devices/usbX/bInt
372 Description:
373 Class code of the interface, i
374
375 See USB specs for its meaning.
376
377 What: /sys/bus/usb/devices/usbX/bInt
378 Description:
379 Interface number, in hexadecim
380
381 See USB specs for its meaning.
382
383 What: /sys/bus/usb/devices/usbX/bInt
384 Description:
385 Protocol code of the interface
386
387 See USB specs for its meaning.
388
389 What: /sys/bus/usb/devices/usbX/bInt
390 Description:
391 Subclass code of the interface
392
393 See USB specs for its meaning.
394
395 What: /sys/bus/usb/devices/usbX/bmAt
396 Description:
397 Attributes of the current conf
398
399 See USB specs for its meaning.
400
401 What: /sys/bus/usb/devices/usbX/bMax
402 Description:
403 Maximum endpoint 0 packet size
404
405 See USB specs for its meaning.
406
407 What: /sys/bus/usb/devices/usbX/bMax
408 Description:
409 Maximum power consumption of t
410 the device, in miliamperes.
411
412 What: /sys/bus/usb/devices/usbX/bNum
413 Description:
414 Number of the possible configu
415 decimal. The current configura
416
417 /sys/bus/usb/devices/u
418
419 See USB specs for its meaning.
420
421 What: /sys/bus/usb/devices/usbX/bNum
422 Description:
423 Number of endpoints used on th
424
425 See USB specs for its meaning.
426
427 What: /sys/bus/usb/devices/usbX/bNum
428 Description:
429 Number of interfaces on this d
430
431 What: /sys/bus/usb/devices/usbX/busn
432 Description:
433 Number of the bus.
434
435 What: /sys/bus/usb/devices/usbX/conf
436 Description:
437 Contents of the string descrip
438 current configuration. It may
439 of a device and/or its serial
440
441 What: /sys/bus/usb/devices/usbX/desc
442 Description:
443 Contains the interface descrip
444
445 What: /sys/bus/usb/devices/usbX/bos_
446 Date: March 2024
447 Contact: Elbert Mai <code@elbertmai.com>
448 Description:
449 Binary file containing the cac
450 of the device. This consists o
451 set of device capability descr
452 this file are in bus-endian fo
453 request the BOS from a device
454
455 What: /sys/bus/usb/devices/usbX/idPr
456 Description:
457 Product ID, in hexadecimal.
458
459 What: /sys/bus/usb/devices/usbX/idVe
460 Description:
461 Vendor ID, in hexadecimal.
462
463 What: /sys/bus/usb/devices/usbX/devs
464 Description:
465 Displays the Device Tree Open
466
467 What: /sys/bus/usb/devices/usbX/avoi
468 Description:
469 Most devices have this set to
470
471 If the value is 1, enable a US
472 device to use reset.
473
474 (read/write)
475
476 What: /sys/bus/usb/devices/usbX/devn
477 Description:
478 USB interface device number, i
479
480 What: /sys/bus/usb/devices/usbX/devp
481 Description:
482 String containing the USB inte
483
484 What: /sys/bus/usb/devices/usbX/manu
485 Description:
486 Vendor specific string contain
487 manufacturer of the device.
488
489 What: /sys/bus/usb/devices/usbX/maxc
490 Description:
491 Number of ports of an USB hub
492
493 What: /sys/bus/usb/devices/usbX/pers
494 Description:
495 Keeps the device even if it ge
496
497 What: /sys/bus/usb/devices/usbX/prod
498 Description:
499 Vendor specific string contain
500 device's product.
501
502 What: /sys/bus/usb/devices/usbX/spee
503 Description:
504 Shows the device's max speed,
505 in Mbps.
506 Can be:
507
508 ======= ======
509 Unknown speed
510 1.5 Low sp
511 15 Full s
512 480 High S
513 5000 Super
514 10000 Super
515 20000 Super
516 ======= ======
517
518 What: /sys/bus/usb/devices/usbX/supp
519 Description:
520 Returns 1 if the device doesn'
521 Otherwise, returns 0.
522
523 What: /sys/bus/usb/devices/usbX/urbn
524 Description:
525 Number of URBs submitted for t
526
527 What: /sys/bus/usb/devices/usbX/vers
528 Description:
529 String containing the USB devi
530 at the BCD descriptor.
531
532 What: /sys/bus/usb/devices/usbX/powe
533 Description:
534 Time in milliseconds for the d
535 value is negative, then autosu
536
537 (read/write)
538
539 What: /sys/bus/usb/devices/usbX/powe
540 Description:
541 The total time the device has
542
543 What: /sys/bus/usb/devices/usbX/powe
544 Description:
545 The total time (in msec) that
546
547 What: /sys/bus/usb/devices/usbX/powe
548 Description:
549
550 What: /sys/bus/usb/devices/usbX/ep_<
551 Description:
552 The address of the endpoint de
553 in hexadecimal. The endpoint d
554 is also shown at:
555
556 /sys/bus/usb/devices/u
557
558 See USB specs for its meaning.
559
560 What: /sys/bus/usb/devices/usbX/ep_<
561 Description:
562 The interval of the endpoint a
563 in hexadecimal. The actual int
564 of the USB. Also shown in time
565 /sys/bus/usb/devices/usbX/ep_<
566
567 What: /sys/bus/usb/devices/usbX/ep_<
568 Description:
569 Number of bytes of the endpoin
570
571 What: /sys/bus/usb/devices/usbX/ep_<
572 Description:
573 Attributes which apply to the
574 descriptor, in hexadecimal. Th
575 bitmapped field is also shown
576
577 /sys/bus/usb/devices/u
578
579 See USB specs for its meaning.
580
581 What: /sys/bus/usb/devices/usbX/ep_<
582 Description:
583 Direction of the endpoint. Can
584
585 - both (on control endpoin
586 - in
587 - out
588
589 What: /sys/bus/usb/devices/usbX/ep_<
590 Description:
591 Interval for polling endpoint
592 milisseconds or microseconds.
593
594 What: /sys/bus/usb/devices/usbX/ep_<
595 Description:
596 Descriptor type. Can be:
597
598 - Control
599 - Isoc
600 - Bulk
601 - Interrupt
602 - unknown
603
604 What: /sys/bus/usb/devices/usbX/ep_<
605 Description:
606 Maximum packet size this endpo
607 sending or receiving, in hexad
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