Re: [PATCH 02/23] dt-bindings: gpio: nomadik: add optional ngpios property

Théo Lebrun
2024-02-19T14:55:09Z

Hello,

On Mon Feb 19, 2024 at 3:50 PM CET, Linus Walleij wrote:
> On Wed, Feb 14, 2024 at 5:24 PM Théo Lebrun <theo.lebrun@bootlin.com> wrote:
>
> > This GPIO controller can support a lesser number of GPIOs than 32.
> > Express that in devicetree using an optional, generic property.
> >
> > Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
> > ---
> > Documentation/devicetree/bindings/gpio/st,nomadik-gpio.yaml | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/gpio/st,nomadik-gpio.yaml b/Documentation/devicetree/bindings/gpio/st,nomadik-gpio.yaml
> > index a999908173d2..bbd23daed229 100644
> > --- a/Documentation/devicetree/bindings/gpio/st,nomadik-gpio.yaml
> > +++ b/Documentation/devicetree/bindings/gpio/st,nomadik-gpio.yaml
> > @@ -50,6 +50,10 @@ properties:
> > gpio-ranges:
> > maxItems: 1
> >
> > + ngpios:
> > + minimum: 0
> > + maximum: 32
>
> I can't help but wonder what good is ngpios = <0>; but OK.
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

A min value is required, else it is equal to the max. There was no
reason to pick anything bigger than zero.

I'll admit it is not a setup I have tested so the driver might have
issues with the ngpios==0 edge-case. Of course I do not expect anyone
to care.

Regards,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering