Re: [PATCH 1/9] dt-bindings: gpio: add bindings for the QIXIS FPGA based GPIO controller

[Krzysztof Kozlowski <krzk@kernel.org>]

On 09/07/2025 13:26, Ioana Ciornei wrote:
> Add a device tree binding for the QIXIS FPGA based GPIO controller.
> Depending on the board, the QIXIS FPGA exposes registers which act as a
> GPIO controller, each with 8 GPIO lines of fixed direction.
> 
> Since each QIXIS FPGA layout has its particularities, add a separate
> compatible string for each board/GPIO register combination supported.
> 
> Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>

Your changelog explains patches, which is kind of redundant - we see
that - but does not explain the dependency you have here between patches.

A nit, subject: drop second/last, redundant "bindings". The
"dt-bindings" prefix is already stating that these are bindings.
See also:
https://elixir.bootlin.com/linux/v6.7-rc8/source/Documentation/devicetree/bindings/submitting-patches.rst#L18

> ---
>  .../bindings/gpio/fsl,fpga-gpio.yaml          | 44 +++++++++++++++++++
>  1 file changed, 44 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/gpio/fsl,fpga-gpio.yaml
> 
> diff --git a/Documentation/devicetree/bindings/gpio/fsl,fpga-gpio.yaml b/Documentation/devicetree/bindings/gpio/fsl,fpga-gpio.yaml
> new file mode 100644
> index 000000000000..dc7b6c0d9b40
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/fsl,fpga-gpio.yaml
> @@ -0,0 +1,44 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/gpio/fsl,fpga-gpio.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: GPIO controller embedded in the NXP QIXIS FPGA
> +
> +maintainers:
> +  - Ioana Ciornei <ioana.ciornei@nxp.com>
> +
> +description: |
> +  This module is part of the QIXIS FPGA found on some Layerscape boards such as
> +  LX2160ARDB and LS1046AQDS. For more details see
> +  ../board/fsl,fpga-qixis-i2c.yaml.

There are no "board" bindings, so this does not feel like correct path.

> +
> +  Each controller supports a maximum of 8 GPIO lines and each line has a fixed
> +  direction which cannot be changed using a direction register.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - fsl,lx2160ardb-fpga-gpio-sfp2
> +      - fsl,lx2160ardb-fpga-gpio-sfp3

What is the difference between these?

> +      - fsl,ls1046aqds-fpga-gpio-stat-pres2

Keep list sorted.


Best regards,
Krzysztof