usb: dwc2: host: spinlock release channel

Prevent dwc2 driver from accessing channel while it frees it.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc2/hcd_ddma.c b/drivers/usb/dwc2/hcd_ddma.c
index 4801e69..a76a58c 100644
--- a/drivers/usb/dwc2/hcd_ddma.c
+++ b/drivers/usb/dwc2/hcd_ddma.c
@@ -360,6 +360,8 @@
  */
 void dwc2_hcd_qh_free_ddma(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
 {
+	unsigned long flags;
+
 	dwc2_desc_list_free(hsotg, qh);
 
 	/*
@@ -369,8 +371,10 @@
 	 * when it comes here from endpoint disable routine
 	 * channel remains assigned.
 	 */
+	spin_lock_irqsave(&hsotg->lock, flags);
 	if (qh->channel)
 		dwc2_release_channel_ddma(hsotg, qh);
+	spin_unlock_irqrestore(&hsotg->lock, flags);
 
 	if ((qh->ep_type == USB_ENDPOINT_XFER_ISOC ||
 	     qh->ep_type == USB_ENDPOINT_XFER_INT) &&