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34 .Nm devctl_clear_driver ,
42 .Nm devctl_set_driver ,
44 .Nd device control library
50 .Fn devctl_attach "const char *device"
52 .Fn devctl_clear_driver "const char *device" "bool force"
54 .Fn devctl_delete "const char *device" "bool force"
56 .Fn devctl_detach "const char *device" "bool force"
58 .Fn devctl_disable "const char *device" "bool force_detach"
60 .Fn devctl_enable "const char *device"
62 .Fn devctl_rescan "const char *device"
64 .Fn devctl_reset "const char *device" "bool detach"
66 .Fn devctl_resume "const char *device"
68 .Fn devctl_set_driver "const char *device" "const char *driver" "bool force"
70 .Fn devctl_suspend "const char *device"
74 library adjusts the state of devices in the kernel's internal device
76 Each control operation accepts a
78 argument that identifies the device to adjust.
81 may be specified as either the name of an existing device or as a
83 The following bus-specific address formats are currently supported:
84 .Bl -tag -offset indent
85 .It Sy pci Ns Fa domain Ns : Ns Fa bus Ns : Ns Fa slot Ns : Ns Fa function
86 A PCI device with the specified
92 .It Sy pci Ns Fa bus Ns : Ns Fa slot Ns : Ns Fa function
93 A PCI device in domain zero with the specified
99 A device with an ACPI handle of
101 The handle must be specified as an absolute path and must begin with a
107 function probes a device and attaches a suitable device driver if one is
112 function detaches a device from its current device driver.
113 The device is left detached until either a new driver for its parent
114 bus is loaded or the device is explicitly probed via
119 the current device driver will be detached even if the device is busy.
123 function deletes a device from the device tree.
128 the device is deleted even if the device is physically present.
132 function disables a device.
133 If the device is currently attached to a device driver,
134 the device driver will be detached from the device,
135 but the device will retain its current name.
139 the current device driver will be detached even if the device is busy.
140 The device will remain disabled and detached until it is explicitly enabled
146 function re-enables a disabled device.
147 The device will probe and attach if a suitable device driver is found.
151 function suspends a device.
152 This may include placing the device in a reduced power state,
153 but any device driver currently attached to the device will remain attached.
157 function resumes a suspended device to a fully working state.
160 .Fn devctl_set_driver
161 function attaches a device driver named
164 If the device is already attached and
167 the request will fail.
168 If the device is already attached and
171 the device will be detached from its current device driver before it is
172 attached to the new device driver.
175 .Fn devctl_clear_driver
176 function resets a device so that it can be attached to any valid device
177 driver rather than only drivers with a previously specified name.
178 This function is used to undo a previous call to
179 .Fn devctl_set_driver .
180 If the device is already attached and
183 the request will fail.
184 If the device is already attached and
187 the device will be detached from its current device driver.
188 After the device's name is reset,
189 it is reprobed and attached to a suitable device driver if one is found.
193 function rescans a bus device checking for devices that have been added or
198 function resets the specified device using bus-specific reset method.
201 argument, if true, specifies that the device driver is detached before
202 the reset, and re-attached afterwards.
203 If false, the device is suspended before the reset, and resumed after.
205 .Rv -std devctl_attach devctl_clear_driver devctl_delete devctl_detach \
206 devctl_disable devctl_enable devctl_suspend devctl_rescan devctl_resume \
209 In addition to specific errors noted below,
212 functions may fail for any of the errors described in
217 The device name is too long.
219 No existing device matches the specified name or location.
221 The current process is not permitted to adjust the state of
227 function may fail if:
230 The device is already attached.
232 An internal memory allocation request failed.
234 The device is disabled.
236 No suitable driver for the device could be found,
237 or the driver failed to attach.
242 function may fail if:
245 The current device driver for
247 is busy and cannot detach at this time.
248 Note that some drivers may return this even if
252 The device is not attached to a driver.
254 The current device driver for
256 does not support detaching.
261 function may fail if:
264 The device is already enabled.
266 An internal memory allocation request failed.
268 No suitable driver for the device could be found,
269 or the driver failed to attach.
274 function may fail if:
277 The current device driver for
279 is busy and cannot detach at this time.
280 Note that some drivers may return this even if
284 The device is already disabled.
286 The current device driver for
288 does not support detaching.
293 function may fail if:
296 The device is already suspended.
298 The device to be suspended is the root bus device.
303 function may fail if:
306 The device is not suspended.
308 The device to be resumed is the root bus device.
312 .Fn devctl_set_driver
313 function may fail if:
316 The device is currently attached to a device driver and
320 The current device driver for
322 is busy and cannot detach at this time.
326 argument points outside the process' allocated address space.
328 No device driver with the requested name exists.
330 An internal memory allocation request failed.
332 The device is disabled.
334 The new device driver failed to attach.
338 .Fn devctl_clear_driver
339 function may fail if:
342 The device is currently attached to a device driver and
346 The current device driver for
348 is busy and cannot detach at this time.
350 The device is not configured for a specific device driver name.
352 The device driver chosen after reprobing failed to attach.
357 function may fail if:
360 The device is not attached to a driver.
362 The bus driver does not support rescanning.
367 function may fail if:
370 The device is physically present and
375 is the root device of the device tree.
380 function may fail if:
383 The bus does not implement the reset method.
385 The device failed to respond after the reset in the time limits
390 function may also return errors caused by the attach, detach, suspend,
391 and resume methods of the device driver.
399 library first appeared in
402 If a device is suspended individually via
404 and the entire machine is subsequently suspended,
405 the device will be resumed when the machine resumes.
407 Similarly, if the device is suspended, and
409 is called on the device with
413 the device is resumed by the
416 Or, if the driver for the device is detached manually, and
418 is called on the device with
422 device reset re-attaches the driver.