Re: [PATCH v2 1/2] dt-bindings: gpio: add gpio-aggregator binding

[Linus Walleij]

On Fri, Feb 13, 2026 at 3:34 PM Rob Herring <robh@xxxxxxxxxx> wrote:

> > > Humm, peripheral boards! So there's a connector. You need a connector
> > > binding. And the one solved binding for such a thing is GPIO! The
> > > gpio-map property lets you remap GPIOs from one provider (the connector)
> > > to a parent provider (soc_gpio). It would look something like this:
> >
> > Well...some GPIOs are wired to peripheral board connectors...but
> > some are wired to things like built in LEDs and a few different
> > on-controller components as well which vary by controller hardware
> > revisions.
> >
> > This gpio-map feature doesn't exist in the mainline kernel does it?
>
> For at least the last 5 years. It's even defined in the DT spec
> (generically as "nexus").

I actually tested this. It works.

It's however a bit annoying that we do not have a single upstream
DTS file using it, so there are no examples to look at other than
in the documentation.

I suppose there would also be greater buy-in to the concept if
we had managed to push the same for at least I2C and SPI,
but it's easy to ask other people to work, I know that.

> > In my device everything I'm wanting to name is off the same gpiochip.
>
> gpio-map completely decouples what the base DT GPIOs look like.

> I suspect there's no support for gpio-line-names alongside gpio-map.
> You get to define how that works.

James sent a proposal that I think looks good for gpiochips
and I think the same can be used for nexi. But I don't know
the esoteric details of the nexi so I might be wrong...

Yours,
Linus Walleij