Re: [PATCH v4 2/2] dt-bindings: gpio: Add devicetree binding for IDT 79RC32434 GPIO controller

From: Rob Herring
Date: Tue May 04 2021 - 09:44:53 EST


On Sat, May 1, 2021 at 7:13 AM Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
>
> On Mon, Apr 26, 2021 at 11:54 AM Thomas Bogendoerfer
> <tsbogend@xxxxxxxxxxxxxxxx> wrote:
>
> > Add YAML devicetree binding for IDT 79RC32434 GPIO controller
> >
> > Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> > ---
> > Changes in v4:
> > - renamed to idt,32434-gpio this time for real
>
> Overall looks good to me.
>
> > +required:
> (...)
> > + - ngpios
>
> Is there a *technical* reason why this is required?
>
> Can't the driver just default to 32 gpios when not specified?
>
> > + - interrupt-controller
> > + - "#interrupt-cells"
> > + - interrupts
>
> Why can't interrupt support be made optional?
>
> It is fine if the driver errors out if not provided, but
> for the bindings this feels optional.
>
> Or does the thing break unless you handle the IRQs?

If the hardware has interrupts, then we should describe that. It's the
OS driver that may or may not support interrupts.

Rob