when commit 
6166c24 (usb: gadget: pxa25x_udc:
convert to udc_start/udc_stop) converted
this driver to udc_start/udc_stop, it failed
to consider the fact that stop_activity()
is called from disconnect interrupt.
Fix the problem so that gadget drivers know
about proper disconnect sequences.
Signed-off-by: Felipe Balbi <balbi@ti.com>
 
        }
        del_timer_sync(&dev->timer);
 
+       /* report disconnect; the driver is already quiesced */
+       if (driver)
+               driver->disconnect(&dev->gadget);
+
        /* re-init driver-visible data structures */
        udc_reinit(dev);
 }