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authorPaul Mackerras <paulus@samba.org>2007-04-29 22:38:01 -0400
committerPaul Mackerras <paulus@samba.org>2007-04-29 22:38:01 -0400
commit49e1900d4cc2e7bcecb681fe60f0990bec2dcce8 (patch)
tree253801ebf57e0a23856a2c7be129c2c178f62fdf /Documentation/ABI/testing/sysfs-bus-usb
parent34f6d749c0a328817d5e36274e53121c1db734dc (diff)
parentb9099ff63c75216d6ca10bce5a1abcd9293c27e6 (diff)
Merge branch 'linux-2.6' into for-2.6.22
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1What: /sys/bus/usb/devices/.../power/autosuspend
2Date: March 2007
3KernelVersion: 2.6.21
4Contact: Alan Stern <stern@rowland.harvard.edu>
5Description:
6 Each USB device directory will contain a file named
7 power/autosuspend. This file holds the time (in seconds)
8 the device must be idle before it will be autosuspended.
9 0 means the device will be autosuspended as soon as
10 possible. Negative values will prevent the device from
11 being autosuspended at all, and writing a negative value
12 will resume the device if it is already suspended.
13
14 The autosuspend delay for newly-created devices is set to
15 the value of the usbcore.autosuspend module parameter.
16
17What: /sys/bus/usb/devices/.../power/level
18Date: March 2007
19KernelVersion: 2.6.21
20Contact: Alan Stern <stern@rowland.harvard.edu>
21Description:
22 Each USB device directory will contain a file named
23 power/level. This file holds a power-level setting for
24 the device, one of "on", "auto", or "suspend".
25
26 "on" means that the device is not allowed to autosuspend,
27 although normal suspends for system sleep will still
28 be honored. "auto" means the device will autosuspend
29 and autoresume in the usual manner, according to the
30 capabilities of its driver. "suspend" means the device
31 is forced into a suspended state and it will not autoresume
32 in response to I/O requests. However remote-wakeup requests
33 from the device may still be enabled (the remote-wakeup
34 setting is controlled separately by the power/wakeup
35 attribute).
36
37 During normal use, devices should be left in the "auto"
38 level. The other levels are meant for administrative uses.
39 If you want to suspend a device immediately but leave it
40 free to wake up in response to I/O requests, you should
41 write "0" to power/autosuspend.