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-rw-r--r--Documentation/ABI/testing/sysfs-bus-usb28
1 files changed, 0 insertions, 28 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
index bcebb9e..294aa86 100644
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -14,34 +14,6 @@ Description:
The autosuspend delay for newly-created devices is set to
the value of the usbcore.autosuspend module parameter.
-What: /sys/bus/usb/devices/.../power/level
-Date: March 2007
-KernelVersion: 2.6.21
-Contact: Alan Stern <stern@rowland.harvard.edu>
-Description:
- Each USB device directory will contain a file named
- power/level. This file holds a power-level setting for
- the device, either "on" or "auto".
-
- "on" means that the device is not allowed to autosuspend,
- although normal suspends for system sleep will still
- be honored. "auto" means the device will autosuspend
- and autoresume in the usual manner, according to the
- capabilities of its driver.
-
- During normal use, devices should be left in the "auto"
- level. The "on" level is meant for administrative uses.
- If you want to suspend a device immediately but leave it
- free to wake up in response to I/O requests, you should
- write "0" to power/autosuspend.
-
- Device not capable of proper suspend and resume should be
- left in the "on" level. Although the USB spec requires
- devices to support suspend/resume, many of them do not.
- In fact so many don't that by default, the USB core
- initializes all non-hub devices in the "on" level. Some
- drivers may change this setting when they are bound.
-
What: /sys/bus/usb/devices/.../power/persist
Date: May 2007
KernelVersion: 2.6.23