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, one of "on", "auto", or "suspend".
+
+ "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. "suspend" means the device
+ is forced into a suspended state and it will not autoresume
+ in response to I/O requests. However remote-wakeup requests
+ from the device may still be enabled (the remote-wakeup
+ setting is controlled separately by the power/wakeup
+ attribute).
+
+ During normal use, devices should be left in the "auto"
+ level. The other levels are 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.
+
+What: /sys/bus/usb/devices/.../power/persist
+Date: May 2007
+KernelVersion: 2.6.23
+Contact: Alan Stern <stern@rowland.harvard.edu>
+Description:
+ If CONFIG_USB_PERSIST is set, then each USB device directory
+ will contain a file named power/persist. The file holds a
+ boolean value (0 or 1) indicating whether or not the
+ "USB-Persist" facility is enabled for the device. Since the
+ facility is inherently dangerous, it is disabled by default
+ for all devices except hubs. For more information, see
+ Documentation/usb/persist.txt.
+
+What: /sys/bus/usb/device/.../power/connected_duration
+Date: January 2008
+KernelVersion: 2.6.25
+Contact: Sarah Sharp <sarah.a.sharp@intel.com>
+Description:
+ If CONFIG_PM and CONFIG_USB_SUSPEND are enabled, then this file
+ is present. When read, it returns the total time (in msec)
+ that the USB device has been connected to the machine. This
+ file is read-only.
+Users:
+ PowerTOP <power@bughost.org>
+ http://www.lesswatts.org/projects/powertop/
+
+What: /sys/bus/usb/device/.../power/active_duration
+Date: January 2008
+KernelVersion: 2.6.25
+Contact: Sarah Sharp <sarah.a.sharp@intel.com>
+Description:
+ If CONFIG_PM and CONFIG_USB_SUSPEND are enabled, then this file
+ is present. When read, it returns the total time (in msec)
+ that the USB device has been active, i.e. not in a suspended
+ state. This file is read-only.
+
+ Tools can use this file and the connected_duration file to
+ compute the percentage of time that a device has been active.
+ For example,
+ echo $((100 * `cat active_duration` / `cat connected_duration`))
+ will give an integer percentage. Note that this does not
+ account for counter wrap.
+Users:
+ PowerTOP <power@bughost.org>
+ http://www.lesswatts.org/projects/powertop/
+
+What: /sys/bus/usb/device/<busnum>-<devnum>...:<config num>-<interface num>/supports_autosuspend
+Date: January 2008
+KernelVersion: 2.6.27
+Contact: Sarah Sharp <sarah.a.sharp@intel.com>
+Description:
+ When read, this file returns 1 if the interface driver
+ for this interface supports autosuspend. It also
+ returns 1 if no driver has claimed this interface, as an
+ unclaimed interface will not stop the device from being
+ autosuspended if all other interface drivers are idle.
+ The file returns 0 if autosuspend support has not been
+ added to the driver.
+Users:
+ USB PM tool
+ git://git.moblin.org/users/sarah/usb-pm-tool/
+
+What: /sys/bus/usb/device/.../authorized
+Date: July 2008
+KernelVersion: 2.6.26
+Contact: David Vrabel <david.vrabel@csr.com>
+Description:
+ Authorized devices are available for use by device
+ drivers, non-authorized one are not. By default, wired
+ USB devices are authorized.
+
+ Certified Wireless USB devices are not authorized
+ initially and should be (by writing 1) after the
+ device has been authenticated.
+
+What: /sys/bus/usb/device/.../wusb_cdid
+Date: July 2008
+KernelVersion: 2.6.27
+Contact: David Vrabel <david.vrabel@csr.com>
+Description:
+ For Certified Wireless USB devices only.
+
+ A devices's CDID, as 16 space-separated hex octets.
+
+What: /sys/bus/usb/device/.../wusb_ck
+Date: July 2008
+KernelVersion: 2.6.27
+Contact: David Vrabel <david.vrabel@csr.com>
+Description:
+ For Certified Wireless USB devices only.
+
+ Write the device's connection key (CK) to start the
+ authentication of the device. The CK is 16
+ space-separated hex octets.
+
+What: /sys/bus/usb/device/.../wusb_disconnect
+Date: July 2008
+KernelVersion: 2.6.27
+Contact: David Vrabel <david.vrabel@csr.com>
+Description:
+ For Certified Wireless USB devices only.
+
+ Write a 1 to force the device to disconnect
+ (equivalent to unplugging a wired USB device).
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff