usb: dwc3: gadget: synchronize_irq dwc irq in suspend

[Felipe Balbi <felipe.balbi@linux.intel.com>]

Hi,

"Wang, Yu1" <yu1.wang@intel.com> writes:
>> > so it's better move the synchronize_irq() after the spin_unlock_irqrestore().
>> > static int dwc3_suspend_common(struct dwc3 *dwc)
>> > {
>> > 	unsigned long	flags;
>> >
>> > 	switch (dwc->dr_mode) {
>> > 	case USB_DR_MODE_PERIPHERAL:
>> > 	case USB_DR_MODE_OTG:
>> > 		spin_lock_irqsave(&dwc->lock, flags);
>> > 		dwc3_gadget_suspend(dwc);
>> > 		spin_unlock_irqrestore(&dwc->lock, flags);
>> > 		synchronize_irq()
>> 
>> indeed, I missed that when I first reviewed the patch. Care to send a fix?
> With this new change, the dwc3 irq thread will be sync after dwc3
> stopped, is this irq thread can be handled correctly for this case?

how about this?

modified   drivers/usb/dwc3/gadget.c
@@ -3373,6 +3373,8 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
 }
 
 int dwc3_gadget_suspend(struct dwc3 *dwc)
+	__releases(dwc->lock)
+	__acquires(dwc->lock)
 {
 	if (!dwc->gadget_driver)
 		return 0;
@@ -3381,7 +3383,9 @@ int dwc3_gadget_suspend(struct dwc3 *dwc)
 	dwc3_disconnect_gadget(dwc);
 	__dwc3_gadget_stop(dwc);
 
+	spin_unlock_irq(dwc->lock);
 	synchronize_irq(dwc->irq_gadget);
+	spin_lock_irq(dwc->lock);
 
 	return 0;
 }

Not the most elegant solution. I'm open to other suggestions.