Re: [PATCH 2/2] uio: add an of_genirq driver

Alan Cox
2009-06-15T08:44:05Z

> I did it that way because I saw IRQ 0 in /proc/interrupts on every PC...
>
> >
> > It is the job of the platform to map a physical IRQ 0 to some other
> > representation if it exists outside of arch specific code.
>
> Funny.
>
> > This was
> > decided some years ago and a large part of the kernel simply doesn't
> > support any notion of a real IRQ 0.
>
> Can you tell me the reason for that decision or point me to some ml archive?

The natural C way to write "No xxx" is if (!xxx) hence

if (!dev->irq) {
polling_start();
return 0;
}

The PC "IRQ 0" is the timer - which only appears in the arch code.

Alan