usb: dwc3: Remove DWC3 locking during gadget suspend/resume

Remove the need for making dwc3_gadget_suspend() and dwc3_gadget_resume()
to be called in a spinlock, as dwc3_gadget_run_stop() could potentially
take some time to complete.

Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
Link: https://lore.kernel.org/r/20220901193625.8727-3-quic_wcheng@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/dwc3/core.c

@@ -1976,9 +1976,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
 	case DWC3_GCTL_PRTCAP_DEVICE:
 		if (pm_runtime_suspended(dwc->dev))
 			break;
-		spin_lock_irqsave(&dwc->lock, flags);
 		dwc3_gadget_suspend(dwc);
-		spin_unlock_irqrestore(&dwc->lock, flags);
 		synchronize_irq(dwc->irq_gadget);
 		dwc3_core_exit(dwc);
 		break;
@@ -2039,9 +2037,7 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
 			return ret;
 
 		dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_DEVICE);
-		spin_lock_irqsave(&dwc->lock, flags);
 		dwc3_gadget_resume(dwc);
-		spin_unlock_irqrestore(&dwc->lock, flags);
 		break;
 	case DWC3_GCTL_PRTCAP_HOST:
 		if (!PMSG_IS_AUTO(msg) && !device_may_wakeup(dwc->dev)) {

drivers/usb/dwc3/gadget.c

@@ -4522,12 +4522,17 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
 
 int dwc3_gadget_suspend(struct dwc3 *dwc)
 {
+	unsigned long flags;
+
 	if (!dwc->gadget_driver)
 		return 0;
 
 	dwc3_gadget_run_stop(dwc, false, false);
+
+	spin_lock_irqsave(&dwc->lock, flags);
 	dwc3_disconnect_gadget(dwc);
 	__dwc3_gadget_stop(dwc);
+	spin_unlock_irqrestore(&dwc->lock, flags);
 
 	return 0;
 }