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References: <20220419071503.1596423-1-patrick.rudolph@9elements.com> <20220419071503.1596423-2-patrick.rudolph@9elements.com>
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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Thu, 21 Apr 2022 22:42:33 +0200
Message-ID: <CACRpkda+yScM20uibGXk3e0fQeG6OBBMQDqSDzNzU5OMPx3zWw@mail.gmail.com>
Subject: Re: [PATCH 1/2] dt-binding: Add cypress,cy8c95x0 binding
To:     Patrick Rudolph <patrick.rudolph@9elements.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        linux-gpio@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
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Hi Patrick,

thanks for your patch!

On Tue, Apr 19, 2022 at 9:17 AM Patrick Rudolph
<patrick.rudolph@9elements.com> wrote:

> Added device tree binding documentation for
> Cypress CY8C95x0 I2C pin-controller.
>
> Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>

> +  '#gpio-cells':
> +    description:
> +      The first cell is the pin number and the second cell is used
> +      to specify optional parameters.
> +    const: 2

Maybe specify that the second cell uses the standard GPIO
parameters in <dt-bindings/gpio/gpio.h>?

The driver is quite elaborate, you can probably list which
parameters you support on this hardware even if the
driver don't even implement them yet: it's just a binding
after all.

> +  ngpios:
> +    minimum: 1
> +    maximum: 60

Why? Isn't it obvious from the compatible how many pins
the GPIO chip has? Then use that instead.
Write under the compatible as description: for each chip
how many gpios it has.

> +patternProperties:
> +  '-pins$':
> +    type: object
> +    description:
> +      Pinctrl node's client devices use subnodes for desired pin configuration.
> +      Client device subnodes use below standard properties.
> +    $ref: "/schemas/pinctrl/pincfg-node.yaml"

This is impressive. It's quite advanced to use the pin config props
for elaborate pin config control.

Yours,
LInus Walleij