Gitweb:     
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=979e524a9c563376af096d2d8629b9969fc06659
Commit:     979e524a9c563376af096d2d8629b9969fc06659
Parent:     1512300689426cb98bfd7e567ee9fdfaaf61b7c7
Author:     Sarah Sharp <[EMAIL PROTECTED]>
AuthorDate: Thu Jan 17 10:24:38 2008 -0800
Committer:  Greg Kroah-Hartman <[EMAIL PROTECTED]>
CommitDate: Fri Feb 1 14:35:00 2008 -0800

    USB: Add documentation for USB suspend statistics.
    
    This documents two newly created files:
    /sys/bus/usb/device/.../power/connected_duration
    /sys/bus/usb/device/.../power/active_duration
    
    Documentation was placed in Documentation/ABI/testing, since that's where 
the
    documentation is for the other USB sysfs power files.
    
    Signed-off-by: Sarah Sharp <[EMAIL PROTECTED]>
    Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]>
---
 Documentation/ABI/testing/sysfs-bus-usb |   33 +++++++++++++++++++++++++++++++
 1 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-usb 
b/Documentation/ABI/testing/sysfs-bus-usb
index 9734577..11a3c16 100644
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -52,3 +52,36 @@ Description:
                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 <[EMAIL PROTECTED]>
+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 <[EMAIL PROTECTED]>
+               http://www.lesswatts.org/projects/powertop/
+
+What:          /sys/bus/usb/device/.../power/active_duration
+Date:          January 2008
+KernelVersion: 2.6.25
+Contact:       Sarah Sharp <[EMAIL PROTECTED]>
+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 <[EMAIL PROTECTED]>
+               http://www.lesswatts.org/projects/powertop/
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to