GitLab

BugLink: http://bugs.launchpad.net/bugs/1573034

commit 972e6a99

 upstream.

The usbhid driver has inconsistently duplicated code in its post-reset,
resume, and reset-resume pathways.

	reset-resume doesn't check HID_STARTED before trying to
	restart the I/O queues.

	resume fails to clear the HID_SUSPENDED flag if HID_STARTED
	isn't set.

	resume calls usbhid_restart_queues() with usbhid->lock held
	and the others call it without holding the lock.

The first item in particular causes a problem following a reset-resume
if the driver hasn't started up its I/O.  URB submission fails because
usbhid->urbin is NULL, and this triggers an unending reset-retry loop.

This patch fixes the problem by creating a new subroutine,
hid_restart_io(), to carry out all the common activities.  It also
adds some checks that were missing in the original code:

	After a reset, there's no need to clear any halted endpoints.

	After a resume, if a reset is pending there's no need to
	restart any I/O until the reset is finished.

	After a resume, if the interrupt-IN endpoint is halted there's
	no need to submit the input URB until the halt has been
	cleared.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Daniel Fraga <fragabr@gmail.com>
Tested-by: Daniel Fraga <fragabr@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>