USB: Allow autosuspend delay to equal 0
This patch (as867) adds an entry for the new power/autosuspend
attribute in Documentation/ABI/testing, and it changes the behavior of
the delay value. Now a delay of 0 means to autosuspend as soon as
possible, and negative values will prevent autosuspend.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
new file mode 100644
index 0000000..00a8432
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -0,0 +1,15 @@
+What: /sys/bus/usb/devices/.../power/autosuspend
+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/autosuspend. This file holds the time (in seconds)
+ the device must be idle before it will be autosuspended.
+ 0 means the device will be autosuspended as soon as
+ possible. Negative values will prevent the device from
+ being autosuspended at all, and writing a negative value
+ will resume the device if it is already suspended.
+
+ The autosuspend delay for newly-created devices is set to
+ the value of the usbcore.autosuspend module parameter.