Re: [PATCH 5/6] USB: Support wakeup IRQ for suspended controllers

Roger Quadros
2013-07-11T07:30:35Z

On 07/10/2013 10:08 PM, Alan Stern wrote:
> On Wed, 10 Jul 2013, Roger Quadros wrote:
>
>> Some platforms e.g. ehci-omap can generate an interrupt
>> (i.e. remote wakeup) even when the controller is suspended i.e.
>> HW_ACCESSIBLE is cleared.
>>
>> Introduce a flag "has_wakeup_irq" in struct usb_hcd to indicate
>> such cases.
>>
>> We tackle this case by disabling the IRQ, scheduling a
>> hub resume and enabling back the IRQ after the controller has
>> resumed. This ensures that the IRQ handler runs only after the
>> controller is accessible.
>
> Oh yes, one more thing...
>
>> @@ -132,6 +134,7 @@ struct usb_hcd {
>> unsigned wireless:1; /* Wireless USB HCD */
>> unsigned authorized_default:1;
>> unsigned has_tt:1; /* Integrated TT in root hub */
>> + unsigned has_wakeup_irq:1; /* Can IRQ when suspended */
>
> Please add a highly visible comment here, warning that has_wakeup_irq
> should never be set on systems with shared IRQs. Having both would ...
> well, it would indicate a really bad system design.
>
OK, will do.

cheers,
-roger