usb: gadget: udc: renesas_usb3: fix deadlock by spinlock

commit 067d6fdc558d2c43f0bfdc7af99630dd5eb08dc5 upstream.

This patch fixes an issue that this driver is possible to cause
deadlock by double-spinclocked in renesas_usb3_stop_controller().
So, this patch removes spinlock API calling in renesas_usb3_stop().
(In other words, the previous code had a redundant lock.)

Fixes: 746bfe63bba3 ("usb: gadget: renesas_usb3: add support for Renesas USB3.0 peripheral controller")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c
index 6be6113..82e301e 100644 (file)
--- a/drivers/usb/gadget/udc/renesas_usb3.c
+++ b/drivers/usb/gadget/udc/renesas_usb3.c
@@ -1718,14 +1718,11 @@ static int renesas_usb3_start(struct usb_gadget *gadget,
 static int renesas_usb3_stop(struct usb_gadget *gadget)
 {
        struct renesas_usb3 *usb3 = gadget_to_renesas_usb3(gadget);
-       unsigned long flags;
 
-       spin_lock_irqsave(&usb3->lock, flags);
        usb3->softconnect = false;
        usb3->gadget.speed = USB_SPEED_UNKNOWN;
        usb3->driver = NULL;
        renesas_usb3_stop_controller(usb3);
-       spin_unlock_irqrestore(&usb3->lock, flags);
 
        pm_runtime_put(usb3_to_dev(usb3));
        pm_runtime_disable(usb3_to_dev(usb3));