1 What: /sys/bus/usb/devices/<INTERFAC 1 What: /sys/bus/usb/devices/<INTERFACE>/authorized
2 Date: August 2015 2 Date: August 2015
3 Description: 3 Description:
4 This allows to authorize (1) o 4 This allows to authorize (1) or deauthorize (0)
5 individual interfaces instead 5 individual interfaces instead a whole device
6 in contrast to the device auth 6 in contrast to the device authorization.
7 If a deauthorized interface wi 7 If a deauthorized interface will be authorized
8 so the driver probing must be 8 so the driver probing must be triggered manually
9 by writing INTERFACE to /sys/b 9 by writing INTERFACE to /sys/bus/usb/drivers_probe
10 This allows to avoid side-effe 10 This allows to avoid side-effects with drivers
11 that need multiple interfaces. 11 that need multiple interfaces.
12 12
13 A deauthorized interface canno 13 A deauthorized interface cannot be probed or claimed.
14 14
15 What: /sys/bus/usb/devices/usbX/inte 15 What: /sys/bus/usb/devices/usbX/interface_authorized_default
16 Date: August 2015 16 Date: August 2015
17 Description: 17 Description:
18 This is used as value that det 18 This is used as value that determines if interfaces
19 would be authorized by default 19 would be authorized by default.
20 The value can be 1 or 0. It's 20 The value can be 1 or 0. It's by default 1.
21 21
22 What: /sys/bus/usb/device/.../author 22 What: /sys/bus/usb/device/.../authorized
23 Date: July 2008 23 Date: July 2008
24 KernelVersion: 2.6.26 24 KernelVersion: 2.6.26
25 Contact: David Vrabel <david.vrabel@csr. 25 Contact: David Vrabel <david.vrabel@csr.com>
26 Description: 26 Description:
27 Authorized devices are availab 27 Authorized devices are available for use by device
28 drivers, non-authorized one ar 28 drivers, non-authorized one are not. By default, wired
29 USB devices are authorized. 29 USB devices are authorized.
30 30
31 What: /sys/bus/usb/drivers/.../new_i 31 What: /sys/bus/usb/drivers/.../new_id
32 Date: October 2011 32 Date: October 2011
33 Contact: linux-usb@vger.kernel.org 33 Contact: linux-usb@vger.kernel.org
34 Description: 34 Description:
35 Writing a device ID to this fi 35 Writing a device ID to this file will attempt to
36 dynamically add a new device I 36 dynamically add a new device ID to a USB device driver.
37 This may allow the driver to s 37 This may allow the driver to support more hardware than
38 was included in the driver's s 38 was included in the driver's static device ID support
39 table at compile time. The for 39 table at compile time. The format for the device ID is:
40 idVendor idProduct bInterfaceC 40 idVendor idProduct bInterfaceClass RefIdVendor RefIdProduct
41 The vendor ID and device ID fi 41 The vendor ID and device ID fields are required, the
42 rest is optional. The `Ref*` t 42 rest is optional. The `Ref*` tuple can be used to tell the
43 driver to use the same driver_ 43 driver to use the same driver_data for the new device as
44 it is used for the reference d 44 it is used for the reference device.
45 Upon successfully adding an ID 45 Upon successfully adding an ID, the driver will probe
46 for the device and attempt to 46 for the device and attempt to bind to it. For example::
47 47
48 # echo "8086 10f5" > /sys/bu 48 # echo "8086 10f5" > /sys/bus/usb/drivers/foo/new_id
49 49
50 Here add a new device (0458:70 50 Here add a new device (0458:7045) using driver_data from
51 an already supported device (0 51 an already supported device (0458:704c)::
52 52
53 # echo "0458 7045 0 0458 704 53 # echo "0458 7045 0 0458 704c" > /sys/bus/usb/drivers/foo/new_id
54 54
55 Reading from this file will li 55 Reading from this file will list all dynamically added
56 device IDs in the same format, 56 device IDs in the same format, with one entry per
57 line. For example:: 57 line. For example::
58 58
59 # cat /sys/bus/usb/drivers/f 59 # cat /sys/bus/usb/drivers/foo/new_id
60 8086 10f5 60 8086 10f5
61 dead beef 06 61 dead beef 06
62 f00d cafe 62 f00d cafe
63 63
64 The list will be truncated at 64 The list will be truncated at PAGE_SIZE bytes due to
65 sysfs restrictions. 65 sysfs restrictions.
66 66
67 What: /sys/bus/usb-serial/drivers/.. 67 What: /sys/bus/usb-serial/drivers/.../new_id
68 Date: October 2011 68 Date: October 2011
69 Contact: linux-usb@vger.kernel.org 69 Contact: linux-usb@vger.kernel.org
70 Description: 70 Description:
71 For serial USB drivers, this a 71 For serial USB drivers, this attribute appears under the
72 extra bus folder "usb-serial" 72 extra bus folder "usb-serial" in sysfs; apart from that
73 difference, all descriptions f 73 difference, all descriptions from the entry
74 "/sys/bus/usb/drivers/.../new_ 74 "/sys/bus/usb/drivers/.../new_id" apply.
75 75
76 What: /sys/bus/usb/drivers/.../remov 76 What: /sys/bus/usb/drivers/.../remove_id
77 Date: November 2009 77 Date: November 2009
78 Contact: CHENG Renquan <rqcheng@smu.edu. 78 Contact: CHENG Renquan <rqcheng@smu.edu.sg>
79 Description: 79 Description:
80 Writing a device ID to this fi 80 Writing a device ID to this file will remove an ID
81 that was dynamically added via 81 that was dynamically added via the new_id sysfs entry.
82 The format for the device ID i 82 The format for the device ID is:
83 idVendor idProduct. After 83 idVendor idProduct. After successfully
84 removing an ID, the driver wil 84 removing an ID, the driver will no longer support the
85 device. This is useful to ens 85 device. This is useful to ensure auto probing won't
86 match the driver to the device 86 match the driver to the device. For example:
87 # echo "046d c315" > /sys/bus/ 87 # echo "046d c315" > /sys/bus/usb/drivers/foo/remove_id
88 88
89 Reading from this file will li 89 Reading from this file will list the dynamically added
90 device IDs, exactly like readi 90 device IDs, exactly like reading from the entry
91 "/sys/bus/usb/drivers/.../new_ 91 "/sys/bus/usb/drivers/.../new_id"
92 92
93 What: /sys/bus/usb/devices/.../power 93 What: /sys/bus/usb/devices/.../power/usb2_hardware_lpm
94 Date: September 2011 94 Date: September 2011
95 Contact: Andiry Xu <andiry.xu@amd.com> 95 Contact: Andiry Xu <andiry.xu@amd.com>
96 Description: 96 Description:
97 If CONFIG_PM is set and a USB 97 If CONFIG_PM is set and a USB 2.0 lpm-capable device is plugged
98 in to a xHCI host which suppor 98 in to a xHCI host which support link PM, it will perform a LPM
99 test; if the test is passed an 99 test; if the test is passed and host supports USB2 hardware LPM
100 (xHCI 1.0 feature), USB2 hardw 100 (xHCI 1.0 feature), USB2 hardware LPM will be enabled for the
101 device and the USB device dire 101 device and the USB device directory will contain a file named
102 power/usb2_hardware_lpm. The 102 power/usb2_hardware_lpm. The file holds a string value (enable
103 or disable) indicating whether 103 or disable) indicating whether or not USB2 hardware LPM is
104 enabled for the device. Develo 104 enabled for the device. Developer can write y/Y/1 or n/N/0 to
105 the file to enable/disable the 105 the file to enable/disable the feature.
106 106
107 What: /sys/bus/usb/devices/.../power 107 What: /sys/bus/usb/devices/.../power/usb3_hardware_lpm_u1
108 /sys/bus/usb/devices/.../power 108 /sys/bus/usb/devices/.../power/usb3_hardware_lpm_u2
109 Date: November 2015 109 Date: November 2015
110 Contact: Kevin Strasser <kevin.strasser@ 110 Contact: Kevin Strasser <kevin.strasser@linux.intel.com>
111 Lu Baolu <baolu.lu@linux.intel. 111 Lu Baolu <baolu.lu@linux.intel.com>
112 Description: 112 Description:
113 If CONFIG_PM is set and a USB 113 If CONFIG_PM is set and a USB 3.0 lpm-capable device is plugged
114 in to a xHCI host which suppor 114 in to a xHCI host which supports link PM, it will check if U1
115 and U2 exit latencies have bee 115 and U2 exit latencies have been set in the BOS descriptor; if
116 the check is passed and the ho 116 the check is passed and the host supports USB3 hardware LPM,
117 USB3 hardware LPM will be enab 117 USB3 hardware LPM will be enabled for the device and the USB
118 device directory will contain 118 device directory will contain two files named
119 power/usb3_hardware_lpm_u1 and 119 power/usb3_hardware_lpm_u1 and power/usb3_hardware_lpm_u2. These
120 files hold a string value (ena 120 files hold a string value (enable or disable) indicating whether
121 or not USB3 hardware LPM U1 or 121 or not USB3 hardware LPM U1 or U2 is enabled for the device.
122 122
123 What: /sys/bus/usb/devices/.../ltm_c 123 What: /sys/bus/usb/devices/.../ltm_capable
124 Date: July 2012 124 Date: July 2012
125 Contact: Sarah Sharp <sarah.a.sharp@linu 125 Contact: Sarah Sharp <sarah.a.sharp@linux.intel.com>
126 Description: 126 Description:
127 USB 3.0 devices may optionally 127 USB 3.0 devices may optionally support Latency Tolerance
128 Messaging (LTM). They indicat 128 Messaging (LTM). They indicate their support by setting a bit
129 in the bmAttributes field of t 129 in the bmAttributes field of their SuperSpeed BOS descriptors.
130 If that bit is set for the dev 130 If that bit is set for the device, ltm_capable will read "yes".
131 If the device doesn't support 131 If the device doesn't support LTM, the file will read "no".
132 The file will be present for a 132 The file will be present for all speeds of USB devices, and will
133 always read "no" for USB 1.1 a 133 always read "no" for USB 1.1 and USB 2.0 devices.
134 134
135 What: /sys/bus/usb/devices/<INTERFAC 135 What: /sys/bus/usb/devices/<INTERFACE>/wireless_status
136 Date: February 2023 136 Date: February 2023
137 Contact: Bastien Nocera <hadess@hadess.n 137 Contact: Bastien Nocera <hadess@hadess.net>
138 Description: 138 Description:
139 Some USB devices use a USB rec 139 Some USB devices use a USB receiver dongle to communicate
140 wirelessly with their device u 140 wirelessly with their device using proprietary protocols. This
141 attribute allows user-space to 141 attribute allows user-space to know whether the device is
142 connected to its receiver dong 142 connected to its receiver dongle, and, for example, consider
143 the device to be absent when c 143 the device to be absent when choosing whether to show the
144 device's battery, show a heads 144 device's battery, show a headset in a list of outputs, or show
145 an on-screen keyboard if the o 145 an on-screen keyboard if the only wireless keyboard is
146 turned off. 146 turned off.
147 This attribute is not to be us 147 This attribute is not to be used to replace protocol specific
148 statuses available in WWAN, WL 148 statuses available in WWAN, WLAN/Wi-Fi, Bluetooth, etc.
149 If the device does not use a r 149 If the device does not use a receiver dongle with a wireless
150 device, then this attribute wi 150 device, then this attribute will not exist.
151 151
152 What: /sys/bus/usb/devices/.../<hub_ 152 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>
153 Date: August 2012 153 Date: August 2012
154 Contact: Lan Tianyu <tianyu.lan@intel.co 154 Contact: Lan Tianyu <tianyu.lan@intel.com>
155 Description: 155 Description:
156 The /sys/bus/usb/devices/.../< 156 The /sys/bus/usb/devices/.../<hub_interface>/port<X>
157 is usb port device's sysfs dir 157 is usb port device's sysfs directory.
158 158
159 What: /sys/bus/usb/devices/.../<hub_ 159 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/connect_type
160 Date: January 2013 160 Date: January 2013
161 Contact: Lan Tianyu <tianyu.lan@intel.co 161 Contact: Lan Tianyu <tianyu.lan@intel.com>
162 Description: 162 Description:
163 Some platforms provide usb por 163 Some platforms provide usb port connect types through ACPI.
164 This attribute is to expose th 164 This attribute is to expose these information to user space.
165 The file will read "hotplug", 165 The file will read "hotplug", "hardwired" and "not used" if the
166 information is available, and 166 information is available, and "unknown" otherwise.
167 167
168 What: /sys/bus/usb/devices/.../<hub_ 168 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/location
169 Date: October 2018 169 Date: October 2018
170 Contact: Bjørn Mork <bjorn@mork.no> 170 Contact: Bjørn Mork <bjorn@mork.no>
171 Description: 171 Description:
172 Some platforms provide usb por 172 Some platforms provide usb port physical location through
173 firmware. This is used by the 173 firmware. This is used by the kernel to pair up logical ports
174 mapping to the same physical c 174 mapping to the same physical connector. The attribute exposes the
175 raw location value as a hex in 175 raw location value as a hex integer.
176 176
177 177
178 What: /sys/bus/usb/devices/.../<hub_ 178 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/quirks
179 Date: May 2018 179 Date: May 2018
180 Contact: Nicolas Boichat <drinkcat@chrom 180 Contact: Nicolas Boichat <drinkcat@chromium.org>
181 Description: 181 Description:
182 In some cases, we care about t 182 In some cases, we care about time-to-active for devices
183 connected on a specific port ( 183 connected on a specific port (e.g. non-standard USB port like
184 pogo pins), where the device t 184 pogo pins), where the device to be connected is known in
185 advance, and behaves well acco 185 advance, and behaves well according to the specification.
186 This attribute is a bit-field 186 This attribute is a bit-field that controls the behavior of
187 a specific port: 187 a specific port:
188 188
189 - Bit 0 of this field selects 189 - Bit 0 of this field selects the "old" enumeration scheme,
190 as it is considerably faste 190 as it is considerably faster (it only causes one USB reset
191 instead of 2). 191 instead of 2).
192 192
193 The old enumeration scheme 193 The old enumeration scheme can also be selected globally
194 using /sys/module/usbcore/p 194 using /sys/module/usbcore/parameters/old_scheme_first, but
195 it is often not desirable a 195 it is often not desirable as the new scheme was introduced to
196 increase compatibility with 196 increase compatibility with more devices.
197 - Bit 1 reduces TRSTRCY to th 197 - Bit 1 reduces TRSTRCY to the 10 ms that are required by the
198 USB 2.0 specification, inst 198 USB 2.0 specification, instead of the 50 ms that are normally
199 used to help make enumerati 199 used to help make enumeration work better on some high speed
200 devices. 200 devices.
201 201
202 What: /sys/bus/usb/devices/.../<hub_ 202 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/over_current_count
203 Date: February 2018 203 Date: February 2018
204 Contact: Richard Leitner <richard.leitne 204 Contact: Richard Leitner <richard.leitner@skidata.com>
205 Description: 205 Description:
206 Most hubs are able to detect o 206 Most hubs are able to detect over-current situations on their
207 ports and report them to the k 207 ports and report them to the kernel. This attribute is to expose
208 the number of over-current sit 208 the number of over-current situation occurred on a specific port
209 to user space. This file will 209 to user space. This file will contain an unsigned 32 bit value
210 which wraps to 0 after its max 210 which wraps to 0 after its maximum is reached. This file supports
211 poll() for monitoring changes 211 poll() for monitoring changes to this value in user space.
212 212
213 Any time this value changes th 213 Any time this value changes the corresponding hub device will send a
214 udev event with the following 214 udev event with the following attributes::
215 215
216 OVER_CURRENT_PORT=/sys/bus/u 216 OVER_CURRENT_PORT=/sys/bus/usb/devices/.../<hub_interface>/port<X>
217 OVER_CURRENT_COUNT=[current 217 OVER_CURRENT_COUNT=[current value of this sysfs attribute]
218 218
219 What: /sys/bus/usb/devices/.../<hub_ 219 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/usb3_lpm_permit
220 Date: November 2015 220 Date: November 2015
221 Contact: Lu Baolu <baolu.lu@linux.intel. 221 Contact: Lu Baolu <baolu.lu@linux.intel.com>
222 Description: 222 Description:
223 Some USB3.0 devices are not fr 223 Some USB3.0 devices are not friendly to USB3 LPM. usb3_lpm_permit
224 attribute allows enabling/disa 224 attribute allows enabling/disabling usb3 lpm of a port. It takes
225 effect both before and after a 225 effect both before and after a usb device is enumerated. Supported
226 values are "0" if both u1 and 226 values are "0" if both u1 and u2 are NOT permitted, "u1" if only u1
227 is permitted, "u2" if only u2 227 is permitted, "u2" if only u2 is permitted, "u1_u2" if both u1 and
228 u2 are permitted. 228 u2 are permitted.
229 229
230 What: /sys/bus/usb/devices/.../<hub_ 230 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/connector
231 Date: December 2021 231 Date: December 2021
232 Contact: Heikki Krogerus <heikki.krogeru 232 Contact: Heikki Krogerus <heikki.krogerus@linux.intel.com>
233 Description: 233 Description:
234 Link to the USB Type-C connect 234 Link to the USB Type-C connector when available. This link is
235 only created when USB Type-C C 235 only created when USB Type-C Connector Class is enabled, and
236 only if the system firmware is 236 only if the system firmware is capable of describing the
237 connection between a port and 237 connection between a port and its connector.
238 238
239 What: /sys/bus/usb/devices/.../<hub_ 239 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/disable
240 Date: June 2022 240 Date: June 2022
241 Contact: Michael Grzeschik <m.grzeschik@ 241 Contact: Michael Grzeschik <m.grzeschik@pengutronix.de>
242 Description: 242 Description:
243 This file controls the state o 243 This file controls the state of a USB port, including
244 Vbus power output (but only on 244 Vbus power output (but only on hubs that support
245 power switching -- most hubs d 245 power switching -- most hubs don't support it). If
246 a port is disabled, the port i 246 a port is disabled, the port is unusable: Devices
247 attached to the port will not 247 attached to the port will not be detected, initialized,
248 or enumerated. 248 or enumerated.
249 249
250 What: /sys/bus/usb/devices/.../<hub_ 250 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/early_stop
251 Date: Sep 2022 251 Date: Sep 2022
252 Contact: Ray Chi <raychi@google.com> 252 Contact: Ray Chi <raychi@google.com>
253 Description: 253 Description:
254 Some USB hosts have some watch 254 Some USB hosts have some watchdog mechanisms so that the device
255 may enter ramdump if it takes 255 may enter ramdump if it takes a long time during port initialization.
256 This attribute allows each por 256 This attribute allows each port just has two attempts so that the
257 port initialization will be fa 257 port initialization will be failed quickly. In addition, if a port
258 which is marked with early_sto 258 which is marked with early_stop has failed to initialize, it will ignore
259 all future connections until t 259 all future connections until this attribute is clear.
260 260
261 What: /sys/bus/usb/devices/.../<hub_ 261 What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/state
262 Date: June 2023 262 Date: June 2023
263 Contact: Roy Luo <royluo@google.com> 263 Contact: Roy Luo <royluo@google.com>
264 Description: 264 Description:
265 Indicates current state of the 265 Indicates current state of the USB device attached to the port.
266 Valid states are: 'not-attache 266 Valid states are: 'not-attached', 'attached', 'powered',
267 'reconnecting', 'unauthenticat 267 'reconnecting', 'unauthenticated', 'default', 'addressed',
268 'configured', and 'suspended'. 268 'configured', and 'suspended'. This file supports poll() to
269 monitor the state change from 269 monitor the state change from user space.
270 270
271 What: /sys/bus/usb/devices/.../power 271 What: /sys/bus/usb/devices/.../power/usb2_lpm_l1_timeout
272 Date: May 2013 272 Date: May 2013
273 Contact: Mathias Nyman <mathias.nyman@li 273 Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
274 Description: 274 Description:
275 USB 2.0 devices may support ha 275 USB 2.0 devices may support hardware link power management (LPM)
276 L1 sleep state. The usb2_lpm_l 276 L1 sleep state. The usb2_lpm_l1_timeout attribute allows
277 tuning the timeout for L1 inac 277 tuning the timeout for L1 inactivity timer (LPM timer), e.g.
278 needed inactivity time before 278 needed inactivity time before host requests the device to go to L1 sleep.
279 Useful for power management tu 279 Useful for power management tuning.
280 Supported values are 0 - 65535 280 Supported values are 0 - 65535 microseconds.
281 281
282 What: /sys/bus/usb/devices/.../power 282 What: /sys/bus/usb/devices/.../power/usb2_lpm_besl
283 Date: May 2013 283 Date: May 2013
284 Contact: Mathias Nyman <mathias.nyman@li 284 Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
285 Description: 285 Description:
286 USB 2.0 devices that support h 286 USB 2.0 devices that support hardware link power management (LPM)
287 L1 sleep state now use a best 287 L1 sleep state now use a best effort service latency value (BESL) to
288 indicate the best effort to re 288 indicate the best effort to resumption of service to the device after the
289 initiation of the resume event 289 initiation of the resume event.
290 If the device does not have a 290 If the device does not have a preferred besl value then the host can select
291 one instead. This usb2_lpm_bes 291 one instead. This usb2_lpm_besl attribute allows to tune the host selected besl
292 value in order to tune power s 292 value in order to tune power saving and service latency.
293 293
294 Supported values are 0 - 15. 294 Supported values are 0 - 15.
295 More information on how besl v 295 More information on how besl values map to microseconds can be found in
296 USB 2.0 ECN Errata for Link Po 296 USB 2.0 ECN Errata for Link Power Management, section 4.10)
297 297
298 What: /sys/bus/usb/devices/.../rx_la 298 What: /sys/bus/usb/devices/.../rx_lanes
299 Date: March 2018 299 Date: March 2018
300 Contact: Mathias Nyman <mathias.nyman@li 300 Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
301 Description: 301 Description:
302 Number of rx lanes the device 302 Number of rx lanes the device is using.
303 USB 3.2 adds Dual-lane support 303 USB 3.2 adds Dual-lane support, 2 rx and 2 tx lanes over Type-C.
304 Inter-Chip SSIC devices suppor 304 Inter-Chip SSIC devices support asymmetric lanes up to 4 lanes per
305 direction. Devices before USB 305 direction. Devices before USB 3.2 are single lane (rx_lanes = 1)
306 306
307 What: /sys/bus/usb/devices/.../tx_la 307 What: /sys/bus/usb/devices/.../tx_lanes
308 Date: March 2018 308 Date: March 2018
309 Contact: Mathias Nyman <mathias.nyman@li 309 Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
310 Description: 310 Description:
311 Number of tx lanes the device 311 Number of tx lanes the device is using.
312 USB 3.2 adds Dual-lane support 312 USB 3.2 adds Dual-lane support, 2 rx and 2 tx -lanes over Type-C.
313 Inter-Chip SSIC devices suppor 313 Inter-Chip SSIC devices support asymmetric lanes up to 4 lanes per
314 direction. Devices before USB 314 direction. Devices before USB 3.2 are single lane (tx_lanes = 1)
315 315
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 316 What: /sys/bus/usb/devices/usbX/bAlternateSetting
326 Description: 317 Description:
327 The current interface alternat 318 The current interface alternate setting number, in decimal.
328 319
329 See USB specs for its meaning. 320 See USB specs for its meaning.
330 321
331 What: /sys/bus/usb/devices/usbX/bcdD 322 What: /sys/bus/usb/devices/usbX/bcdDevice
332 Description: 323 Description:
333 The device's release number, i 324 The device's release number, in hexadecimal.
334 325
335 See USB specs for its meaning. 326 See USB specs for its meaning.
336 327
337 What: /sys/bus/usb/devices/usbX/bCon 328 What: /sys/bus/usb/devices/usbX/bConfigurationValue
338 Description: 329 Description:
339 While a USB device typically h 330 While a USB device typically have just one configuration
340 setting, some devices support 331 setting, some devices support multiple configurations.
341 332
342 This value shows the current c 333 This value shows the current configuration, in decimal.
343 334
344 Changing its value will change 335 Changing its value will change the device's configuration
345 to another setting. 336 to another setting.
346 337
347 The number of configurations s 338 The number of configurations supported by a device is at:
348 339
349 /sys/bus/usb/devices/u 340 /sys/bus/usb/devices/usbX/bNumConfigurations
350 341
351 See USB specs for its meaning. 342 See USB specs for its meaning.
352 343
353 What: /sys/bus/usb/devices/usbX/bDev 344 What: /sys/bus/usb/devices/usbX/bDeviceClass
354 Description: 345 Description:
355 Class code of the device, in h 346 Class code of the device, in hexadecimal.
356 347
357 See USB specs for its meaning. 348 See USB specs for its meaning.
358 349
359 What: /sys/bus/usb/devices/usbX/bDev 350 What: /sys/bus/usb/devices/usbX/bDeviceProtocol
360 Description: 351 Description:
361 Protocol code of the device, i 352 Protocol code of the device, in hexadecimal.
362 353
363 See USB specs for its meaning. 354 See USB specs for its meaning.
364 355
365 What: /sys/bus/usb/devices/usbX/bDev 356 What: /sys/bus/usb/devices/usbX/bDeviceSubClass
366 Description: 357 Description:
367 Subclass code of the device, i 358 Subclass code of the device, in hexadecimal.
368 359
369 See USB specs for its meaning. 360 See USB specs for its meaning.
370 361
371 What: /sys/bus/usb/devices/usbX/bInt 362 What: /sys/bus/usb/devices/usbX/bInterfaceClass
372 Description: 363 Description:
373 Class code of the interface, i 364 Class code of the interface, in hexadecimal.
374 365
375 See USB specs for its meaning. 366 See USB specs for its meaning.
376 367
377 What: /sys/bus/usb/devices/usbX/bInt 368 What: /sys/bus/usb/devices/usbX/bInterfaceNumber
378 Description: 369 Description:
379 Interface number, in hexadecim 370 Interface number, in hexadecimal.
380 371
381 See USB specs for its meaning. 372 See USB specs for its meaning.
382 373
383 What: /sys/bus/usb/devices/usbX/bInt 374 What: /sys/bus/usb/devices/usbX/bInterfaceProtocol
384 Description: 375 Description:
385 Protocol code of the interface 376 Protocol code of the interface, in hexadecimal.
386 377
387 See USB specs for its meaning. 378 See USB specs for its meaning.
388 379
389 What: /sys/bus/usb/devices/usbX/bInt 380 What: /sys/bus/usb/devices/usbX/bInterfaceSubClass
390 Description: 381 Description:
391 Subclass code of the interface 382 Subclass code of the interface, in hexadecimal.
392 383
393 See USB specs for its meaning. 384 See USB specs for its meaning.
394 385
395 What: /sys/bus/usb/devices/usbX/bmAt 386 What: /sys/bus/usb/devices/usbX/bmAttributes
396 Description: 387 Description:
397 Attributes of the current conf 388 Attributes of the current configuration, in hexadecimal.
398 389
399 See USB specs for its meaning. 390 See USB specs for its meaning.
400 391
401 What: /sys/bus/usb/devices/usbX/bMax 392 What: /sys/bus/usb/devices/usbX/bMaxPacketSize0
402 Description: 393 Description:
403 Maximum endpoint 0 packet size 394 Maximum endpoint 0 packet size, in decimal.
404 395
405 See USB specs for its meaning. 396 See USB specs for its meaning.
406 397
407 What: /sys/bus/usb/devices/usbX/bMax 398 What: /sys/bus/usb/devices/usbX/bMaxPower
408 Description: 399 Description:
409 Maximum power consumption of t 400 Maximum power consumption of the active configuration of
410 the device, in miliamperes. 401 the device, in miliamperes.
411 402
412 What: /sys/bus/usb/devices/usbX/bNum 403 What: /sys/bus/usb/devices/usbX/bNumConfigurations
413 Description: 404 Description:
414 Number of the possible configu 405 Number of the possible configurations of the device, in
415 decimal. The current configura 406 decimal. The current configuration is controlled via:
416 407
417 /sys/bus/usb/devices/u 408 /sys/bus/usb/devices/usbX/bConfigurationValue
418 409
419 See USB specs for its meaning. 410 See USB specs for its meaning.
420 411
421 What: /sys/bus/usb/devices/usbX/bNum 412 What: /sys/bus/usb/devices/usbX/bNumEndpoints
422 Description: 413 Description:
423 Number of endpoints used on th 414 Number of endpoints used on this interface, in hexadecimal.
424 415
425 See USB specs for its meaning. 416 See USB specs for its meaning.
426 417
427 What: /sys/bus/usb/devices/usbX/bNum 418 What: /sys/bus/usb/devices/usbX/bNumInterfaces
428 Description: 419 Description:
429 Number of interfaces on this d 420 Number of interfaces on this device, in decimal.
430 421
431 What: /sys/bus/usb/devices/usbX/busn 422 What: /sys/bus/usb/devices/usbX/busnum
432 Description: 423 Description:
433 Number of the bus. 424 Number of the bus.
434 425
435 What: /sys/bus/usb/devices/usbX/conf 426 What: /sys/bus/usb/devices/usbX/configuration
436 Description: 427 Description:
437 Contents of the string descrip 428 Contents of the string descriptor associated with the
438 current configuration. It may 429 current configuration. It may include the firmware version
439 of a device and/or its serial 430 of a device and/or its serial number.
440 431
441 What: /sys/bus/usb/devices/usbX/desc 432 What: /sys/bus/usb/devices/usbX/descriptors
442 Description: 433 Description:
443 Contains the interface descrip 434 Contains the interface descriptors, in binary.
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 <<
454 435
455 What: /sys/bus/usb/devices/usbX/idPr 436 What: /sys/bus/usb/devices/usbX/idProduct
456 Description: 437 Description:
457 Product ID, in hexadecimal. 438 Product ID, in hexadecimal.
458 439
459 What: /sys/bus/usb/devices/usbX/idVe 440 What: /sys/bus/usb/devices/usbX/idVendor
460 Description: 441 Description:
461 Vendor ID, in hexadecimal. 442 Vendor ID, in hexadecimal.
462 443
463 What: /sys/bus/usb/devices/usbX/devs 444 What: /sys/bus/usb/devices/usbX/devspec
464 Description: 445 Description:
465 Displays the Device Tree Open 446 Displays the Device Tree Open Firmware node of the interface.
466 447
467 What: /sys/bus/usb/devices/usbX/avoi 448 What: /sys/bus/usb/devices/usbX/avoid_reset_quirk
468 Description: 449 Description:
469 Most devices have this set to 450 Most devices have this set to zero.
470 451
471 If the value is 1, enable a US 452 If the value is 1, enable a USB quirk that prevents this
472 device to use reset. 453 device to use reset.
473 454
474 (read/write) 455 (read/write)
475 456
476 What: /sys/bus/usb/devices/usbX/devn 457 What: /sys/bus/usb/devices/usbX/devnum
477 Description: 458 Description:
478 USB interface device number, i 459 USB interface device number, in decimal.
479 460
480 What: /sys/bus/usb/devices/usbX/devp 461 What: /sys/bus/usb/devices/usbX/devpath
481 Description: 462 Description:
482 String containing the USB inte 463 String containing the USB interface device path.
483 464
484 What: /sys/bus/usb/devices/usbX/manu 465 What: /sys/bus/usb/devices/usbX/manufacturer
485 Description: 466 Description:
486 Vendor specific string contain 467 Vendor specific string containing the name of the
487 manufacturer of the device. 468 manufacturer of the device.
488 469
489 What: /sys/bus/usb/devices/usbX/maxc 470 What: /sys/bus/usb/devices/usbX/maxchild
490 Description: 471 Description:
491 Number of ports of an USB hub 472 Number of ports of an USB hub
492 473
493 What: /sys/bus/usb/devices/usbX/pers 474 What: /sys/bus/usb/devices/usbX/persist
494 Description: 475 Description:
495 Keeps the device even if it ge 476 Keeps the device even if it gets disconnected.
496 477
497 What: /sys/bus/usb/devices/usbX/prod 478 What: /sys/bus/usb/devices/usbX/product
498 Description: 479 Description:
499 Vendor specific string contain 480 Vendor specific string containing the name of the
500 device's product. 481 device's product.
501 482
502 What: /sys/bus/usb/devices/usbX/spee 483 What: /sys/bus/usb/devices/usbX/speed
503 Description: 484 Description:
504 Shows the device's max speed, 485 Shows the device's max speed, according to the USB version,
505 in Mbps. 486 in Mbps.
506 Can be: 487 Can be:
507 488
508 ======= ====== 489 ======= ====================
509 Unknown speed 490 Unknown speed unknown
510 1.5 Low sp 491 1.5 Low speed
511 15 Full s 492 15 Full speed
512 480 High S 493 480 High Speed
513 5000 Super 494 5000 Super Speed
514 10000 Super 495 10000 Super Speed+
515 20000 Super 496 20000 Super Speed+ Gen 2x2
516 ======= ====== 497 ======= ====================
517 498
518 What: /sys/bus/usb/devices/usbX/supp 499 What: /sys/bus/usb/devices/usbX/supports_autosuspend
519 Description: 500 Description:
520 Returns 1 if the device doesn' 501 Returns 1 if the device doesn't support autosuspend.
521 Otherwise, returns 0. 502 Otherwise, returns 0.
522 503
523 What: /sys/bus/usb/devices/usbX/urbn 504 What: /sys/bus/usb/devices/usbX/urbnum
524 Description: 505 Description:
525 Number of URBs submitted for t 506 Number of URBs submitted for the whole device.
526 507
527 What: /sys/bus/usb/devices/usbX/vers 508 What: /sys/bus/usb/devices/usbX/version
528 Description: 509 Description:
529 String containing the USB devi 510 String containing the USB device version, as encoded
530 at the BCD descriptor. 511 at the BCD descriptor.
531 512
532 What: /sys/bus/usb/devices/usbX/powe 513 What: /sys/bus/usb/devices/usbX/power/autosuspend
533 Description: 514 Description:
534 Time in milliseconds for the d 515 Time in milliseconds for the device to autosuspend. If the
535 value is negative, then autosu 516 value is negative, then autosuspend is prevented.
536 517
537 (read/write) 518 (read/write)
538 519
539 What: /sys/bus/usb/devices/usbX/powe 520 What: /sys/bus/usb/devices/usbX/power/active_duration
540 Description: 521 Description:
541 The total time the device has 522 The total time the device has not been suspended.
542 523
543 What: /sys/bus/usb/devices/usbX/powe 524 What: /sys/bus/usb/devices/usbX/power/connected_duration
544 Description: 525 Description:
545 The total time (in msec) that 526 The total time (in msec) that the device has been connected.
546 527
547 What: /sys/bus/usb/devices/usbX/powe 528 What: /sys/bus/usb/devices/usbX/power/level
548 Description: 529 Description:
549 530
550 What: /sys/bus/usb/devices/usbX/ep_< 531 What: /sys/bus/usb/devices/usbX/ep_<N>/bEndpointAddress
551 Description: 532 Description:
552 The address of the endpoint de 533 The address of the endpoint described by this descriptor,
553 in hexadecimal. The endpoint d 534 in hexadecimal. The endpoint direction on this bitmapped field
554 is also shown at: 535 is also shown at:
555 536
556 /sys/bus/usb/devices/u 537 /sys/bus/usb/devices/usbX/ep_<N>/direction
557 538
558 See USB specs for its meaning. 539 See USB specs for its meaning.
559 540
560 What: /sys/bus/usb/devices/usbX/ep_< 541 What: /sys/bus/usb/devices/usbX/ep_<N>/bInterval
561 Description: 542 Description:
562 The interval of the endpoint a 543 The interval of the endpoint as described on its descriptor,
563 in hexadecimal. The actual int 544 in hexadecimal. The actual interval depends on the version
564 of the USB. Also shown in time 545 of the USB. Also shown in time units at
565 /sys/bus/usb/devices/usbX/ep_< 546 /sys/bus/usb/devices/usbX/ep_<N>/interval.
566 547
567 What: /sys/bus/usb/devices/usbX/ep_< 548 What: /sys/bus/usb/devices/usbX/ep_<N>/bLength
568 Description: 549 Description:
569 Number of bytes of the endpoin 550 Number of bytes of the endpoint descriptor, in hexadecimal.
570 551
571 What: /sys/bus/usb/devices/usbX/ep_< 552 What: /sys/bus/usb/devices/usbX/ep_<N>/bmAttributes
572 Description: 553 Description:
573 Attributes which apply to the 554 Attributes which apply to the endpoint as described on its
574 descriptor, in hexadecimal. Th 555 descriptor, in hexadecimal. The endpoint type on this
575 bitmapped field is also shown 556 bitmapped field is also shown at:
576 557
577 /sys/bus/usb/devices/u 558 /sys/bus/usb/devices/usbX/ep_<N>/type
578 559
579 See USB specs for its meaning. 560 See USB specs for its meaning.
580 561
581 What: /sys/bus/usb/devices/usbX/ep_< 562 What: /sys/bus/usb/devices/usbX/ep_<N>/direction
582 Description: 563 Description:
583 Direction of the endpoint. Can 564 Direction of the endpoint. Can be:
584 565
585 - both (on control endpoin 566 - both (on control endpoints)
586 - in 567 - in
587 - out 568 - out
588 569
589 What: /sys/bus/usb/devices/usbX/ep_< 570 What: /sys/bus/usb/devices/usbX/ep_<N>/interval
590 Description: 571 Description:
591 Interval for polling endpoint 572 Interval for polling endpoint for data transfers, in
592 milisseconds or microseconds. 573 milisseconds or microseconds.
593 574
594 What: /sys/bus/usb/devices/usbX/ep_< 575 What: /sys/bus/usb/devices/usbX/ep_<N>/type
595 Description: 576 Description:
596 Descriptor type. Can be: 577 Descriptor type. Can be:
597 578
598 - Control 579 - Control
599 - Isoc 580 - Isoc
600 - Bulk 581 - Bulk
601 - Interrupt 582 - Interrupt
602 - unknown 583 - unknown
603 584
604 What: /sys/bus/usb/devices/usbX/ep_< 585 What: /sys/bus/usb/devices/usbX/ep_<N>/wMaxPacketSize
605 Description: 586 Description:
606 Maximum packet size this endpo 587 Maximum packet size this endpoint is capable of
607 sending or receiving, in hexad 588 sending or receiving, in hexadecimal.
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