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

Hi Bartosz,

On Wed, 11 Feb 2026 at 10:47, Bartosz Golaszewski [off-list ref] wrote:

On Wed, Feb 11, 2026 at 9:14 AM James Hilliard
[off-list ref] wrote:

quoted

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 <redacted>

quoted

--- 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 [off-list ref]

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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