USB: change interface to usb_lock_device_for_reset()

This patch (as1161) changes the interface to
usb_lock_device_for_reset().  The existing interface is apparently not
very clear, judging from the fact that several of its callers don't
use it correctly.  The new interface always returns 0 for success and
it always requires the caller to unlock the device afterward.

The new routine will not return immediately if it is called while the
driver's probe method is running.  Instead it will wait until the
probe is over and the device has been unlocked.  This shouldn't cause
any problems; I don't know of any cases where drivers call
usb_lock_device_for_reset() during probe.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 3 insertions, 5 deletions

diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c
index 79108d5d3171..2058db41618c 100644
--- a/drivers/usb/storage/transport.c
+++ b/drivers/usb/storage/transport.c
@@ -1173,10 +1173,9 @@ int usb_stor_Bulk_reset(struct us_data *us)
  */
 int usb_stor_port_reset(struct us_data *us)
 {
-        int result, rc_lock;
+        int result;
 
-        result = rc_lock =
-                usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
+        result = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
         if (result < 0)
                 US_DEBUGP("unable to lock device for reset: %d\n", result);
         else {
@@ -1189,8 +1188,7 @@ int usb_stor_port_reset(struct us_data *us)
                         US_DEBUGP("usb_reset_device returns %d\n",
                                         result);
                 }
-                if (rc_lock)
-                        usb_unlock_device(us->pusb_dev);
+                usb_unlock_device(us->pusb_dev);
         }
         return result;
 }