USB: usb peripheral controller driver oops avoidance

I'm having problem with oopses when rebooting, if I modprobe g_serial
and rmmod g_serial and do a reboot I get an oops in device_shutdown().
The reason seems to be that usb_gadget_unregister_driver() doesn't do
enough cleanup.  With this at91_udc patch I don't get the oops.

Signed-off-by: Patrik Sevallius <patrik.sevallius@enea.com>
[ Same bug was in other peripheral controller drivers; fixed ]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/usb/gadget/goku_udc.c b/drivers/usb/gadget/goku_udc.c
index 2ec9d196a8cf..d3e702576de6 100644
--- a/drivers/usb/gadget/goku_udc.c
+++ b/drivers/usb/gadget/goku_udc.c
@@ -1422,6 +1422,7 @@ int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
         spin_unlock_irqrestore(&dev->lock, flags);
 
         driver->unbind(&dev->gadget);
+        dev->gadget.dev.driver = NULL;
 
         DBG(dev, "unregistered driver '%s'\n", driver->driver.name);
         return 0;