Re: [PATCH v2 2/2] gpio: aggregator: add gpio-aggregator DT compatible

[Geert Uytterhoeven]

Hi Bartosz,

On Wed, 11 Feb 2026 at 10:47, Bartosz Golaszewski <brgl@xxxxxxxxxx> wrote:
> On Wed, Feb 11, 2026 at 9:14 AM James Hilliard
> <james.hilliard1@xxxxxxxxx> wrote:
> >
> > Add an OF match entry for "gpio-aggregator" to support plain GPIO
> > forwarding from devicetree without delay semantics.
> >
> > This allows exposing selected lines as a logical GPIO controller with
> > stable aggregated offsets, so consumers can reference forwarded lines
> > instead of physical controller offsets. It also allows creating bundled
> > groups of named lines that can be exposed to userspace as a convenient
> > virtual gpiochip interface. Using "gpio-delay" for this case is not
> > suitable because it enables delay features and requires 3-cell GPIO
> > specifiers.
> >
> > Signed-off-by: James Hilliard <james.hilliard1@xxxxxxxxx>

> > --- a/drivers/gpio/gpio-aggregator.c
> > +++ b/drivers/gpio/gpio-aggregator.c
> > @@ -1635,6 +1635,9 @@ static int gpio_aggregator_probe(struct platform_device *pdev)
> >  }
> >
> >  static const struct of_device_id gpio_aggregator_dt_ids[] = {
> > +       {
> > +               .compatible = "gpio-aggregator",
> > +       },
> >         {
> >                 .compatible = "gpio-delay",
> >                 .data = (void *)FWD_FEATURE_DELAY,
> > --
> > 2.43.0
> >
>
> Regardless of the DT bindings - this change is perfectly fine. We do
> that for other "virtual" devices like gpio-sim, gpio-virtuser, etc. I
> would just ask you to document it under
> Documentation/admin-guide/gpio/gpio-aggregator.rst.

This is not a pure virtual device, but for use with actual hardware.

Nacked-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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