USB: make autosuspend delay a module parameter

This patch (as859) makes the default USB autosuspend delay a module
parameter of usbcore.  By setting the delay value at boot time, users
will be able to prevent the system from autosuspending devices which
for some reason can't handle it.

The patch also stores the autosuspend delay as a per-device value.  A
later patch will allow the user to change the value, tailoring the
delay for each individual device.  A delay value of 0 will prevent
autosuspend.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 7 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index c479d30eeaa3..03eb5ed503f7 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1758,6 +1758,13 @@ and is between 256 and 4096 characters. It is defined in the file
                         Note that genuine overcurrent events won't be
                         reported either.
 
+        usbcore.autosuspend=
+                        [USB] The autosuspend time delay (in seconds) used
+                        for newly-detected USB devices (default 2).  This
+                        is the time required before an idle device will be
+                        autosuspended.  Devices for which the delay is set
+                        to 0 won't be autosuspended at all.
+
         usbhid.mousepoll=
                         [USBHID] The interval which mice are to be polled at.