2 .\" Copyright (c) 2014 John Baldwin <jhb@FreeBSD.org>
3 .\" All rights reserved.
5 .\" Redistribution and use in source and binary forms, with or without
6 .\" modification, are permitted provided that the following conditions
8 .\" 1. Redistributions of source code must retain the above copyright
9 .\" notice, this list of conditions and the following disclaimer.
10 .\" 2. Redistributions in binary form must reproduce the above copyright
11 .\" notice, this list of conditions and the following disclaimer in the
12 .\" documentation and/or other materials provided with the distribution.
14 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 .Nm devctl_clear_driver ,
43 .Nm devctl_set_driver ,
46 .Nd device control library
52 .Fn devctl_attach "const char *device"
54 .Fn devctl_clear_driver "const char *device" "bool force"
56 .Fn devctl_delete "const char *device" "bool force"
58 .Fn devctl_detach "const char *device" "bool force"
60 .Fn devctl_disable "const char *device" "bool force_detach"
62 .Fn devctl_enable "const char *device"
64 .Fn devctl_freeze "void"
66 .Fn devctl_rescan "const char *device"
68 .Fn devctl_reset "const char *device" "bool detach"
70 .Fn devctl_resume "const char *device"
72 .Fn devctl_set_driver "const char *device" "const char *driver" "bool force"
74 .Fn devctl_suspend "const char *device"
76 .Fn devctl_thaw "void"
80 library adjusts the state of devices in the kernel's internal device
82 Each control operation accepts a
84 argument that identifies the device to adjust.
87 may be specified as either the name of an existing device or as a
89 The following bus-specific address formats are currently supported:
90 .Bl -tag -offset indent
91 .It Sy pci Ns Fa domain Ns : Ns Fa bus Ns : Ns Fa slot Ns : Ns Fa function
92 A PCI device with the specified
98 .It Sy pci Ns Fa bus Ns : Ns Fa slot Ns : Ns Fa function
99 A PCI device in domain zero with the specified
105 A device with an ACPI handle of
107 The handle must be specified as an absolute path and must begin with a
113 function probes a device and attaches a suitable device driver if one is
118 function detaches a device from its current device driver.
119 The device is left detached until either a new driver for its parent
120 bus is loaded or the device is explicitly probed via
125 the current device driver will be detached even if the device is busy.
129 function deletes a device from the device tree.
134 the device is deleted even if the device is physically present.
138 function disables a device.
139 If the device is currently attached to a device driver,
140 the device driver will be detached from the device,
141 but the device will retain its current name.
145 the current device driver will be detached even if the device is busy.
146 The device will remain disabled and detached until it is explicitly enabled
152 function re-enables a disabled device.
153 The device will probe and attach if a suitable device driver is found.
157 function suspends a device.
158 This may include placing the device in a reduced power state,
159 but any device driver currently attached to the device will remain attached.
163 function resumes a suspended device to a fully working state.
166 .Fn devctl_set_driver
167 function attaches a device driver named
170 If the device is already attached and
173 the request will fail.
174 If the device is already attached and
177 the device will be detached from its current device driver before it is
178 attached to the new device driver.
181 .Fn devctl_clear_driver
182 function resets a device so that it can be attached to any valid device
183 driver rather than only drivers with a previously specified name.
184 This function is used to undo a previous call to
185 .Fn devctl_set_driver .
186 If the device is already attached and
189 the request will fail.
190 If the device is already attached and
193 the device will be detached from its current device driver.
194 After the device's name is reset,
195 it is reprobed and attached to a suitable device driver if one is found.
199 function rescans a bus device checking for devices that have been added or
204 function freezes probe and attach processing initiated in response to
205 drivers being loaded.
209 function resumes (thaws the freeze) probe and attach processing
210 initiated in response to drivers being loaded.
214 function resets the specified device using bus-specific reset method.
217 argument, if true, specifies that the device driver is detached before
218 the reset, and re-attached afterwards.
219 If false, the device is suspended before the reset, and resumed after.
221 .Rv -std devctl_attach devctl_clear_driver devctl_delete devctl_detach \
222 devctl_disable devctl_enable devctl_suspend devctl_rescan devctl_resume \
225 In addition to specific errors noted below,
228 functions may fail for any of the errors described in
233 The device name is too long.
235 No existing device matches the specified name or location.
237 The current process is not permitted to adjust the state of
243 function may fail if:
246 The device is already attached.
248 An internal memory allocation request failed.
250 The device is disabled.
252 No suitable driver for the device could be found,
253 or the driver failed to attach.
258 function may fail if:
261 The current device driver for
263 is busy and cannot detach at this time.
264 Note that some drivers may return this even if
268 The device is not attached to a driver.
270 The current device driver for
272 does not support detaching.
277 function may fail if:
280 The device is already enabled.
282 An internal memory allocation request failed.
284 No suitable driver for the device could be found,
285 or the driver failed to attach.
290 function may fail if:
293 The current device driver for
295 is busy and cannot detach at this time.
296 Note that some drivers may return this even if
300 The device is already disabled.
302 The current device driver for
304 does not support detaching.
309 function may fail if:
312 The device is already suspended.
314 The device to be suspended is the root bus device.
319 function may fail if:
322 The device is not suspended.
324 The device to be resumed is the root bus device.
328 .Fn devctl_set_driver
329 function may fail if:
332 The device is currently attached to a device driver and
336 The current device driver for
338 is busy and cannot detach at this time.
342 argument points outside the process' allocated address space.
344 No device driver with the requested name exists.
346 An internal memory allocation request failed.
348 The device is disabled.
350 The new device driver failed to attach.
354 .Fn devctl_clear_driver
355 function may fail if:
358 The device is currently attached to a device driver and
362 The current device driver for
364 is busy and cannot detach at this time.
366 The device is not configured for a specific device driver name.
368 The device driver chosen after reprobing failed to attach.
373 function may fail if:
376 The device is not attached to a driver.
378 The bus driver does not support rescanning.
383 function may fail if:
386 The device is physically present and
391 is the root device of the device tree.
396 function may fail if:
399 The bus does not implement the reset method.
401 The device failed to respond after the reset in the time limits
406 function may also return errors caused by the attach, detach, suspend,
407 and resume methods of the device driver.
415 library first appeared in
418 If a device is suspended individually via
420 and the entire machine is subsequently suspended,
421 the device will be resumed when the machine resumes.
423 Similarly, if the device is suspended, and
425 is called on the device with
429 the device is resumed by the
432 Or, if the driver for the device is detached manually, and
434 is called on the device with
438 device reset re-attaches the driver.