usb: gadget: pch_udc: Fix disconnect issue

BugLink: http://bugs.launchpad.net/bugs/987337

commit c50a3bff0edb0acd49d8033a12ea4668e09a31ad upstream.

ISSUE:
When the driver notifies a gadget of a disconnect event, a system
rarely freezes.

CAUSE:
When the driver calls dev->driver->disconnect(), it is not calling
spin_unlock().

Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/drivers/usb/gadget/pch_udc.c b/drivers/usb/gadget/pch_udc.c
index 5048a0c..147ec4e 100644 (file)
--- a/drivers/usb/gadget/pch_udc.c
+++ b/drivers/usb/gadget/pch_udc.c
@@ -2335,8 +2335,11 @@ static void pch_udc_svc_ur_interrupt(struct pch_udc_dev *dev)
                /* Complete request queue */
                empty_req_queue(ep);
        }
                /* Complete request queue */
                empty_req_queue(ep);
        }

-       if (dev->driver && dev->driver->disconnect)
+       if (dev->driver && dev->driver->disconnect) {
+               spin_unlock(&dev->lock);

                dev->driver->disconnect(&dev->gadget);
                dev->driver->disconnect(&dev->gadget);

+               spin_lock(&dev->lock);
+       }

 }
 
 /**
 }
 
 /**