USB: UHCI: fix for suspend of virtual HP controller
authorAlan Stern <stern@rowland.harvard.edu>
Tue, 14 May 2013 17:55:29 +0000 (13:55 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 7 Jun 2013 19:49:12 +0000 (12:49 -0700)
commitee4998cca0218751458709c0db61d258adb6a86d
treebd8b3c68bc01897a1ee4a089cc74055144649730
parent99d96e8cd47fddbe3170339889440d44181a6f03
USB: UHCI: fix for suspend of virtual HP controller

commit 997ff893603c6455da4c5e26ba1d0f81adfecdfc upstream.

HP's virtual UHCI host controller takes a long time to suspend
(several hundred microseconds), even when no devices are attached.
This provokes a warning message from uhci-hcd in the auto-stop case.

To prevent this from happening, this patch adds a test to avoid
performing an auto-stop when the wait_for_hp quirk flag is set.  The
controller will still suspend through the normal runtime PM mechanism.
And since that pathway includes a 1-ms delay, the slowness of the
virtual hardware won't matter.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: ZhenHua <zhen-hual@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/uhci-hub.c