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27 .\" $FreeBSD: head/lib/libusb/libusb.3 277165 2015-01-14 06:46:25Z hselasky $
28 .\"
29 .Dd January 5, 2014
30 .Dt LIBUSB 3
31 .Os
32 .Sh NAME
33 .Nm libusb
34 .Nd "USB access library"
35 .Sh LIBRARY
36 .Lb libusb
37 .Sh SYNOPSIS
38 .In libusb.h
39 .Sh DESCRIPTION
40 The
41 .Nm
42 library contains interfaces for directly managing a usb device.
43 The current implementation supports v1.0 of the libusb API.
44 .Sh LIBRARY INITIALISATION AND DEINITIALISATION
45 .Ft int
46 .Fn libusb_init "libusb_context **ctx"
47 This function initialises libusb.
48 It must be called at the beginning
49 of the program, before other libusb routines are used.
50 This function returns 0 on success or LIBUSB_ERROR on
51 failure.
52 .Pp
53 .Ft void
54 .Fn libusb_exit "libusb_context *ctx"
55 Deinitialise libusb.
56 Must be called at the end of the application.
57 Other libusb routines may not be called after this function.
58 .Pp
59 .Ft const char *
60 .Fn libusb_strerror "int code"
61 Get the ASCII representation of the error given by the
62 .Fa code
63 argument.
64 This function does not return NULL.
65 .Pp
66 .Ft const char *
67 .Fn libusb_error_name "int code"
68 Get the ASCII representation of the error enum given by the
69 .Fa code
70 argument.
71 This function does not return NULL.
72 .Pp
73 .Ft void
74 .Fn libusb_set_debug "libusb_context *ctx" "int level"
75 Set the debug level to
76 .Fa level .
77 .Pp
78 .Ft ssize_t
79 .Fn libusb_get_device_list "libusb_context *ctx" "libusb_device ***list"
80 Populate
81 .Fa list
82 with the list of usb devices available, adding a reference to each
83 device in the list.
84 All the list entries created by this
85 function must have their reference counter
86 decremented when you are done with them,
87 and the list itself must be freed.
88 This
89 function returns the number of devices in the list or a LIBUSB_ERROR code.
90 .Pp
91 .Ft void
92 .Fn libusb_free_device_list "libusb_device **list" "int unref_devices"
93 Free the list of devices discovered by libusb_get_device_list.
94 If
95 .Fa unref_device
96 is set to 1 all devices in the list have their reference
97 counter decremented once.
98 .Pp
99 .Ft uint8_t
100 .Fn libusb_get_bus_number "libusb_device *dev"
101 Returns the number of the bus contained by the device
102 .Fa dev .
103 .Pp
104 .Ft int
105 .Fn libusb_get_port_numbers "libusb_device *dev" "uint8_t *buf" "uint8_t bufsize"
106 Stores, in the buffer
107 .Fa buf
108 of size
109 .Fa bufsize ,
110 the list of all port numbers from root for the device
111 .Fa dev .
112 .Pp
113 .Ft int
114 .Fn libusb_get_port_path "libusb_context *ctx" "libusb_device *dev" "uint8_t *buf" "uint8_t bufsize"
115 Deprecated function equivalent to libusb_get_port_numbers.
116 .Pp
117 .Ft uint8_t
118 .Fn libusb_get_device_address "libusb_device *dev"
119 Returns the device_address contained by the device
120 .Fa dev .
121 .Pp
122 .Ft enum libusb_speed
123 .Fn libusb_get_device_speed "libusb_device *dev"
124 Returns the wire speed at which the device is connected.
125 See the LIBUSB_SPEED_XXX enums for more information.
126 LIBUSB_SPEED_UNKNOWN is returned in case of unknown wire speed.
127 .Pp
128 .Ft int
129 .Fn libusb_get_max_packet_size "libusb_device *dev" "unsigned char endpoint"
130 Returns the wMaxPacketSize value on success, LIBUSB_ERROR_NOT_FOUND if the
131 endpoint does not exist and LIBUSB_ERROR_OTHERS on other failure.
132 .Pp
133 .Ft int
134 .Fn libusb_get_max_iso_packet_size "libusb_device *dev" "unsigned char endpoint"
135 Returns the packet size multiplied by the packet multiplier on success,
136 LIBUSB_ERROR_NOT_FOUND if the endpoint does not exist and
137 LIBUSB_ERROR_OTHERS on other failure.
138 .Pp
139 .Ft libusb_device *
140 .Fn libusb_ref_device "libusb_device *dev"
141 Increment the reference counter of the device
142 .Fa dev .
143 .Pp
144 .Ft void
145 .Fn libusb_unref_device "libusb_device *dev"
146 Decrement the reference counter of the device
147 .Fa dev .
148 .Pp
149 .Ft int
150 .Fn libusb_open "libusb_device *dev" "libusb_device_handle **devh"
151 Open a device and obtain a device_handle.
152 Returns 0 on success,
153 LIBUSB_ERROR_NO_MEM on memory allocation problems, LIBUSB_ERROR_ACCESS
154 on permissions problems, LIBUSB_ERROR_NO_DEVICE if the device has been
155 disconnected and a LIBUSB_ERROR code on other errors.
156 .Pp
157 .Ft libusb_device_handle *
158 .Fn libusb_open_device_with_vid_pid "libusb_context *ctx" "uint16_t vid" "uint16_t pid"
159 A convenience function to open a device by vendor and product IDs
160 .Fa vid
161 and
162 .Fa pid .
163 Returns NULL on error.
164 .Pp
165 .Ft void
166 .Fn libusb_close "libusb_device_handle *devh"
167 Close a device handle.
168 .Pp
169 .Ft libusb_device *
170 .Fn libusb_get_device "libusb_device_handle *devh"
171 Get the device contained by devh.
172 Returns NULL on error.
173 .Pp
174 .Ft int
175 .Fn libusb_get_configuration "libusb_device_handle *devh" "int *config"
176 Returns the value of the current configuration.
177 Returns 0
178 on success, LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
179 and a LIBUSB_ERROR code on error.
180 .Pp
181 .Ft int
182 .Fn libusb_set_configuration "libusb_device_handle *devh" "int config"
183 Set the active configuration to
184 .Fa config
185 for the device contained by
186 .Fa devh .
187 This function returns 0 on success, LIBUSB_ERROR_NOT_FOUND if the requested
188 configuration does not exist, LIBUSB_ERROR_BUSY if the interfaces are currently
189 claimed, LIBUSB_ERROR_NO_DEVICE if the device has been disconnected and a
190 LIBUSB_ERROR code on failure.
191 .Pp
192 .Ft int
193 .Fn libusb_claim_interface "libusb_device_handle *devh" "int interface_number"
194 Claim an interface in a given libusb_handle
195 .Fa devh .
196 This is a non-blocking function.
197 It returns 0 on success, LIBUSB_ERROR_NOT_FOUND
198 if the requested interface does not exist, LIBUSB_ERROR_BUSY if a program or
199 driver has claimed the interface, LIBUSB_ERROR_NO_DEVICE if the device has
200 been disconnected and a LIBUSB_ERROR code on failure.
201 .Pp
202 .Ft int
203 .Fn libusb_release_interface "libusb_device_handle *devh" "int interface_number"
204 This function releases an interface.
205 All the claimed interfaces on a device must be released
206 before closing the device.
207 Returns 0 on success, LIBUSB_ERROR_NOT_FOUND if the
208 interface was not claimed, LIBUSB_ERROR_NO_DEVICE if the device has been
209 disconnected and LIBUSB_ERROR on failure.
210 .Pp
211 .Ft int
212 .Fn libusb_set_interface_alt_setting "libusb_device_handle *dev" "int interface_number" "int alternate_setting"
213 Activate an alternate setting for an interface.
214 Returns 0 on success,
215 LIBUSB_ERROR_NOT_FOUND if the interface was not claimed or the requested
216 setting does not exist, LIBUSB_ERROR_NO_DEVICE if the device has been
217 disconnected and a LIBUSB_ERROR code on failure.
218 .Pp
219 .Ft int
220 .Fn libusb_clear_halt "libusb_device_handle *devh" "unsigned char endpoint"
221 Clear an halt/stall for a endpoint.
222 Returns 0 on success, LIBUSB_ERROR_NOT_FOUND
223 if the endpoint does not exist, LIBUSB_ERROR_NO_DEVICE if the device has been
224 disconnected and a LIBUSB_ERROR code on failure.
225 .Pp
226 .Ft int
227 .Fn libusb_reset_device "libusb_device_handle *devh"
228 Perform an USB port reset for an usb device.
229 Returns 0 on success,
230 LIBUSB_ERROR_NOT_FOUND if re-enumeration is required or if the device has
231 been disconnected and a LIBUSB_ERROR code on failure.
232 .Pp
233 .Ft int
234 .Fn libusb_check_connected "libusb_device_handle *devh"
235 Test if the USB device is still connected.
236 Returns 0 on success,
237 LIBUSB_ERROR_NO_DEVICE if it has been disconnected and a LIBUSB_ERROR
238 code on failure.
239 .Pp
240 .Ft int
241 .Fn libusb_kernel_driver_active "libusb_device_handle *devh" "int interface"
242 Determine if a driver is active on a interface.
243 Returns 0 if no kernel driver is active
244 and 1 if a kernel driver is active, LIBUSB_ERROR_NO_DEVICE
245 if the device has been disconnected and a LIBUSB_ERROR code on failure.
246 .Pp
247 .Ft int
248 .Fn libusb_get_driver "libusb_device_handle *devh" "int interface" "char *name" "int namelen"
249 or
250 .Ft int
251 .Fn libusb_get_driver_np "libusb_device_handle *devh" "int interface" "char *name" "int namelen"
252 Copy the name of the driver attached to the given
253 .Fa device
254 and
255 .Fa interface
256 into the buffer
257 .Fa name
258 of length
259 .Fa namelen .
260 Returns 0 on success, LIBUSB_ERROR_NOT_FOUND if no kernel driver is attached
261 to the given interface and LIBUSB_ERROR_INVALID_PARAM if the interface does
262 not exist.
263 This function is non-portable.
264 The buffer pointed to by
265 .Fa name
266 is only zero terminated on success.
267 .Pp
268 .Ft int
269 .Fn libusb_detach_kernel_driver "libusb_device_handle *devh" "int interface"
270 or
271 .Ft int
272 .Fn libusb_detach_kernel_driver_np "libusb_device_handle *devh" "int interface"
273 Detach a kernel driver from an interface.
274 This is needed to claim an interface already claimed by a kernel driver.
275 Returns 0 on success, LIBUSB_ERROR_NOT_FOUND if no kernel driver was active,
276 LIBUSB_ERROR_INVALID_PARAM if the interface does not exist,
277 LIBUSB_ERROR_NO_DEVICE if the device has been disconnected
278 and a LIBUSB_ERROR code on failure.
279 This function is non-portable.
280 .Pp
281 .Ft int
282 .Fn libusb_attach_kernel_driver "libusb_device_handle *devh" "int interface"
283 Re-attach an interface kernel driver that was previously detached.
284 Returns 0 on success,
285 LIBUSB_ERROR_INVALID_PARAM if the interface does not exist,
286 LIBUSB_ERROR_NO_DEVICE
287 if the device has been disconnected, LIBUSB_ERROR_BUSY if the driver cannot be
288 attached because the interface is claimed by a program or driver and a
289 LIBUSB_ERROR code on failure.
290 .Sh USB DESCRIPTORS
291 .Ft int
292 .Fn libusb_get_device_descriptor "libusb_device *dev" "libusb_device_descriptor *desc"
293 Get the USB device descriptor for the device
294 .Fa dev .
295 This is a non-blocking function.
296 Returns 0 on success and a LIBUSB_ERROR code on
297 failure.
298 .Pp
299 .Ft int
300 .Fn libusb_get_active_config_descriptor "libusb_device *dev" "struct libusb_config_descriptor **config"
301 Get the USB configuration descriptor for the active configuration.
302 Returns 0 on
303 success, LIBUSB_ERROR_NOT_FOUND if the device is in
304 an unconfigured state
305 and a LIBUSB_ERROR code on error.
306 .Pp
307 .Ft int
308 .Fn libusb_get_config_descriptor "libusb_device *dev" "uint8_t config_index" "libusb_config_descriptor **config"
309 Get a USB configuration descriptor based on its index
310 .Fa idx .
311 Returns 0 on success, LIBUSB_ERROR_NOT_FOUND if the configuration does not exist
312 and a LIBUSB_ERROR code on error.
313 .Pp
314 .Ft int
315 .Fn libusb_get_config_descriptor_by_value "libusb_device *dev" "uint8 bConfigurationValue" "libusb_config_descriptor **config"
316 Get a USB configuration descriptor with a specific bConfigurationValue.
317 This is
318 a non-blocking function which does not send a request through the device.
319 Returns 0
320 on success, LIBUSB_ERROR_NOT_FOUND if the configuration
321 does not exist and a
322 LIBUSB_ERROR code on failure.
323 .Pp
324 .Ft void
325 .Fn libusb_free_config_descriptor "libusb_config_descriptor *config"
326 Free a configuration descriptor.
327 .Pp
328 .Ft int
329 .Fn libusb_get_string_descriptor "libusb_device_handle *devh" "uint8_t desc_idx" "uint16_t langid" "unsigned char *data" "int length"
330 Retrieve a string descriptor in raw format.
331 Returns the number of bytes actually transferred on success
332 or a negative LIBUSB_ERROR code on failure.
333 .Pp
334 .Ft int
335 .Fn libusb_get_string_descriptor_ascii "libusb_device_handle *devh" "uint8_t desc_idx" "unsigned char *data" "int length"
336 Retrieve a string descriptor in C style ASCII.
337 Returns the positive number of bytes in the resulting ASCII string
338 on success and a LIBUSB_ERROR code on failure.
339 .Pp
340 .Ft int
341 .Fn libusb_parse_ss_endpoint_comp "const void *buf" "int len" "libusb_ss_endpoint_companion_descriptor **ep_comp"
342 This function parses the USB 3.0 endpoint companion descriptor in host endian format pointed to by
343 .Fa buf
344 and having a length of
345 .Fa len .
346 Typically these arguments are the extra and extra_length fields of the
347 endpoint descriptor.
348 On success the pointer to resulting descriptor is stored at the location given by
349 .Fa ep_comp .
350 Returns zero on success and a LIBUSB_ERROR code on failure.
351 On success the parsed USB 3.0 endpoint companion descriptor must be
352 freed using the libusb_free_ss_endpoint_comp function.
353 .Pp
354 .Ft void
355 .Fn libusb_free_ss_endpoint_comp "libusb_ss_endpoint_companion_descriptor *ep_comp"
356 This function is NULL safe and frees a parsed USB 3.0 endpoint companion descriptor.
357 .Pp
358 .Ft int
359 .Fn libusb_parse_bos_descriptor "const void *buf" "int len" "libusb_bos_descriptor **bos"
360 This function parses a Binary Object Store, BOS, descriptor into host endian format pointed to by
361 .Fa buf
362 and having a length of
363 .Fa len .
364 On success the pointer to resulting descriptor is stored at the location given by
365 .Fa bos .
366 Returns zero on success and a LIBUSB_ERROR code on failure.
367 On success the parsed BOS descriptor must be freed using the
368 libusb_free_bos_descriptor function.
369 .Pp
370 .Ft void
371 .Fn libusb_free_bos_descriptor "libusb_bos_descriptor *bos"
372 This function is NULL safe and frees a parsed BOS descriptor.
373 .Sh USB ASYNCHRONOUS I/O
374 .Ft struct libusb_transfer *
375 .Fn libusb_alloc_transfer "int iso_packets"
376 Allocate a transfer with the number of isochronous packet descriptors
377 specified by
378 .Fa iso_packets .
379 Returns NULL on error.
380 .Pp
381 .Ft void
382 .Fn libusb_free_transfer "struct libusb_transfer *tr"
383 Free a transfer.
384 .Pp
385 .Ft int
386 .Fn libusb_submit_transfer "struct libusb_transfer *tr"
387 This function will submit a transfer and returns immediately.
388 Returns 0 on success, LIBUSB_ERROR_NO_DEVICE if
389 the device has been disconnected and a
390 LIBUSB_ERROR code on other failure.
391 .Pp
392 .Ft int
393 .Fn libusb_cancel_transfer "struct libusb_transfer *tr"
394 This function asynchronously cancels a transfer.
395 Returns 0 on success and a LIBUSB_ERROR code on failure.
396 .Sh USB SYNCHRONOUS I/O
397 .Ft int
398 .Fn libusb_control_transfer "libusb_device_handle *devh" "uint8_t bmRequestType" "uint8_t bRequest" "uint16_t wValue" "uint16_t wIndex" "unsigned char *data" "uint16_t wLength" "unsigned int timeout"
399 Perform a USB control transfer.
400 Returns the actual number of bytes
401 transferred on success, in the range from and including zero up to and
402 including
403 .Fa wLength .
404 On error a LIBUSB_ERROR code is returned, for example
405 LIBUSB_ERROR_TIMEOUT if the transfer timed out, LIBUSB_ERROR_PIPE if the
406 control request was not supported, LIBUSB_ERROR_NO_DEVICE if the
407 device has been disconnected and another LIBUSB_ERROR code on other failures.
408 The LIBUSB_ERROR codes are all negative.
409 .Pp
410 .Ft int
411 .Fn libusb_bulk_transfer "struct libusb_device_handle *devh" "unsigned char endpoint" "unsigned char *data" "int length" "int *transferred" "unsigned int timeout"
412 Perform an USB bulk transfer.
413 A timeout value of zero means no timeout.
414 The timeout value is given in milliseconds.
415 Returns 0 on success, LIBUSB_ERROR_TIMEOUT
416 if the transfer timed out, LIBUSB_ERROR_PIPE if the control request was not
417 supported, LIBUSB_ERROR_OVERFLOW if the device offered more data,
418 LIBUSB_ERROR_NO_DEVICE if the device has been disconnected and
419 a LIBUSB_ERROR code on other failure.
420 .Pp
421 .Ft int
422 .Fn libusb_interrupt_transfer "struct libusb_device_handle *devh" "unsigned char endpoint" "unsigned char *data" "int length" "int *transferred" "unsigned int timeout"
423 Perform an USB Interrupt transfer.
424 A timeout value of zero means no timeout.
425 The timeout value is given in milliseconds.
426 Returns 0 on success, LIBUSB_ERROR_TIMEOUT
427 if the transfer timed out, LIBUSB_ERROR_PIPE if the control request was not
428 supported, LIBUSB_ERROR_OVERFLOW if the device offered more data,
429 LIBUSB_ERROR_NO_DEVICE if the device has been disconnected and
430 a LIBUSB_ERROR code on other failure.
431 .Sh USB EVENTS
432 .Ft int
433 .Fn libusb_try_lock_events "libusb_context *ctx"
434 Try to acquire the event handling lock.
435 Returns 0 if the lock was obtained and 1 if not.
436 .Pp
437 .Ft void
438 .Fn libusb_lock_events "libusb_context *ctx"
439 Acquire the event handling lock.
440 This function is blocking.
441 .Pp
442 .Ft void
443 .Fn libusb_unlock_events "libusb_context *ctx"
444 Release the event handling lock.
445 This will wake up any thread blocked
446 on
447 .Fn libusb_wait_for_event .
448 .Pp
449 .Ft int
450 .Fn libusb_event_handling_ok "libusb_context *ctx"
451 Determine if it still OK for this thread to be doing event handling.
452 Returns 1
453 if event handling can start or continue.
454 Returns 0 if this thread must give up
455 the events lock.
456 .Pp
457 .Ft int
458 .Fn libusb_event_handler_active "libusb_context *ctx"
459 Determine if an active thread is handling events.
460 Returns 1 if there is a thread handling events and 0 if there
461 are no threads currently handling events.
462 .Pp
463 .Ft void
464 .Fn libusb_lock_event_waiters "libusb_context *ctx"
465 Acquire the event_waiters lock.
466 This lock is designed to be obtained in the
467 situation where you want to be aware when events are completed, but some other
468 thread is event handling so calling libusb_handle_events() is not allowed.
469 .Pp
470 .Ft void
471 .Fn libusb_unlock_event_waiters "libusb_context *ctx"
472 Release the event_waiters lock.
473 .Pp
474 .Ft int
475 .Fn libusb_wait_for_event "libusb_context *ctx" "struct timeval *tv"
476 Wait for another thread to signal completion of an event.
477 Must be called
478 with the event waiters lock held, see libusb_lock_event_waiters().
479 This will
480 block until the timeout expires or a transfer completes or a thread releases
481 the event handling lock through libusb_unlock_events().
482 Returns 0 after a
483 transfer completes or another thread stops event handling, and 1 if the
484 timeout expired.
485 .Pp
486 .Ft int
487 .Fn libusb_handle_events_timeout_completed "libusb_context *ctx" "struct timeval *tv" "int *completed"
488 Handle any pending events by checking if timeouts have expired and by
489 checking the set of file descriptors for activity.
490 If the
491 .Fa completed
492 argument is not equal to NULL, this function will
493 loop until a transfer completion callback sets the variable pointed to
494 by the
495 .Fa completed
496 argument to non-zero.
497 If the
498 .Fa tv
499 argument is not equal to NULL, this function will return
500 LIBUSB_ERROR_TIMEOUT after the given timeout.
501 Returns 0 on success, or a LIBUSB_ERROR code on failure or timeout.
502 .Pp
503 .Ft int
504 .Fn libusb_handle_events_completed "libusb_context *ctx" "int *completed"
505 Handle any pending events by checking the set of file descriptors for activity.
506 If the
507 .Fa completed
508 argument is not equal to NULL, this function will
509 loop until a transfer completion callback sets the variable pointed to
510 by the
511 .Fa completed
512 argument to non-zero.
513 Returns 0 on success, or a LIBUSB_ERROR code on failure.
514 .Pp
515 .Ft int
516 .Fn libusb_handle_events_timeout "libusb_context *ctx" "struct timeval *tv"
517 Handle any pending events by checking if timeouts have expired and by
518 checking the set of file descriptors for activity.
519 Returns 0 on success, or a
520 LIBUSB_ERROR code on failure or timeout.
521 .Pp
522 .Ft int
523 .Fn libusb_handle_events "libusb_context *ctx"
524 Handle any pending events in blocking mode with a sensible timeout.
525 Returns 0
526 on success and a LIBUSB_ERROR code on failure.
527 .Pp
528 .Ft int
529 .Fn libusb_handle_events_locked "libusb_context *ctx" "struct timeval *tv"
530 Handle any pending events by polling file descriptors, without checking if
531 another thread is already doing so.
532 Must be called with the event lock held.
533 .Pp
534 .Ft int
535 .Fn libusb_get_next_timeout "libusb_context *ctx" "struct timeval *tv"
536 Determine the next internal timeout that libusb needs to handle.
537 Returns 0
538 if there are no pending timeouts, 1 if a timeout was returned, or a LIBUSB_ERROR
539 code on failure or timeout.
540 .Pp
541 .Ft void
542 .Fn libusb_set_pollfd_notifiers "libusb_context *ctx" "libusb_pollfd_added_cb added_cb" "libusb_pollfd_removed_cb remove_cb" "void *user_data"
543 Register notification functions for file descriptor additions/removals.
544 These functions will be invoked for every new or removed file descriptor
545 that libusb uses as an event source.
546 .Pp
547 .Ft const struct libusb_pollfd **
548 .Fn libusb_get_pollfds "libusb_context *ctx"
549 Retrieve a list of file descriptors that should be polled by your main loop as
550 libusb event sources.
551 Returns a NULL-terminated list on success or NULL on failure.
552 .Sh LIBUSB VERSION 0.1 COMPATIBILITY
553 The library is also compliant with LibUSB version 0.1.12.
554 .Pp
555 .Fn usb_open
556 .Fn usb_close
557 .Fn usb_get_string
558 .Fn usb_get_string_simple
559 .Fn usb_get_descriptor_by_endpoint
560 .Fn usb_get_descriptor
561 .Fn usb_parse_descriptor
562 .Fn usb_parse_configuration
563 .Fn usb_destroy_configuration
564 .Fn usb_fetch_and_parse_descriptors
565 .Fn usb_bulk_write
566 .Fn usb_bulk_read
567 .Fn usb_interrupt_write
568 .Fn usb_interrupt_read
569 .Fn usb_control_msg
570 .Fn usb_set_configuration
571 .Fn usb_claim_interface
572 .Fn usb_release_interface
573 .Fn usb_set_altinterface
574 .Fn usb_resetep
575 .Fn usb_clear_halt
576 .Fn usb_reset
577 .Fn usb_strerror
578 .Fn usb_init
579 .Fn usb_set_debug
580 .Fn usb_find_busses
581 .Fn usb_find_devices
582 .Fn usb_device
583 .Fn usb_get_busses
584 .Fn usb_check_connected
585 .Fn usb_get_driver_np
586 .Fn usb_detach_kernel_driver_np
587 .Sh SEE ALSO
588 .Xr libusb20 3 ,
589 .Xr usb 4 ,
590 .Xr usbconfig 8 ,
591 .Xr usbdump 8
592 .Pp
593 .Pa http://libusb.sourceforge.net/
594 .Sh HISTORY
595 .Nm
596 support first appeared in
597 .Fx 8.0 .