usb: musb: fix hanging when rmmod gadget driver

If we try to modprobe a second gadget driver before
rmmoding the first one, the reference for the first
gadget driver would get NULLed avoiding usb to change
gadget drivers later.

Cc: David Brownell <david-b@pacbell.net>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 7 insertions, 9 deletions

diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c
index b3773f13ee0a..d6a802c224fa 100644
--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -1710,17 +1710,15 @@ int usb_gadget_register_driver(struct usb_gadget_driver *driver)
 
         spin_unlock_irqrestore(&musb->lock, flags);
 
-        if (retval == 0)
+        if (retval == 0) {
                 retval = driver->bind(&musb->g);
-        if (retval != 0) {
-                DBG(3, "bind to driver %s failed --> %d\n",
-                        driver->driver.name, retval);
-                musb->gadget_driver = NULL;
-                musb->g.dev.driver = NULL;
-        }
+                if (retval != 0) {
+                        DBG(3, "bind to driver %s failed --> %d\n",
+                                        driver->driver.name, retval);
+                        musb->gadget_driver = NULL;
+                        musb->g.dev.driver = NULL;
+                }
 
-        /* start peripheral and/or OTG engines */
-        if (retval == 0) {
                 spin_lock_irqsave(&musb->lock, flags);
 
                 /* REVISIT always use otg_set_peripheral(), handling