[PATCH v3 6/7] dt-bindings: pinctrl: rockchip: Add RMIO controller binding

[Linus Walleij]

Hi Ye,

thanks for your patch!

On Tue, Dec 16, 2025 at 3:50 PM Ye Zhang <ye.zhang at rock-chips.com> wrote:


> diff --git a/Documentation/devicetree/bindings/pinctrl/rockchip,rmio.yaml b/Documentation/devicetree/bindings/pinctrl/rockchip,rmio.yaml

> +  rockchip,rmio-grf:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      The phandle of the syscon node (GRF or PMU) containing the RMIO registers.
> +      This property is required if the RMIO registers are located in a different
> +      syscon than the parent pinctrl node.
> +
> +  rockchip,offset:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      The offset of the RMIO configuration registers within the GRF.

Can't this just be a cell in the phandle?

> +  rockchip,pins-num:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      The number of physical pins supported by this RMIO instance.
> +      Used for boundary checking and driver initialization.

Isn't this implicit from the compatible? Why is this different
between two device trees using the same compatible pin
controller? I don't get it, I think this should be a constant in the
code based on the compatible instead.

> +patternProperties:
> +  "^[a-z0-9-]+$":
> +    type: object
> +    description:
> +      Function node grouping multiple groups.
> +
> +    patternProperties:
> +      "^[a-z0-9-]+$":
> +        type: object
> +        description:
> +          Group node containing the pinmux configuration.
> +
> +        properties:
> +          rockchip,rmio:
> +            $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +            description:
> +              A list of pin-function pairs. The format is <pin_id function_id>.
> +            minItems: 1
> +            items:
> +              items:
> +                - description: RMIO Pin ID (0 to pins-num - 1)
> +                  minimum: 0
> +                  maximum: 31
> +                - description: Function ID
> +                  minimum: 0
> +                  maximum: 98

Please avoid these custom properties and just use the standard
"pinmux" property. I don't want any more opaque custom bindings
for functions and groups.

Reference Documentation/devicetree/bindings/pinctrl/pinmux-node.yaml
and use pinmux from there.

You can use some shifting and defines to shoehorn your config
into a single u32 and parse that in your driver; i.e. instead of
rockchip,rmio = <1, 2>;
use
pinmux = <1 << 8 | 2 << 0>;
these shifter numerals can come from defines.
In the driver shift & mask out the components you want.

e.g.;

> +            rmio-uart {
> +                rmio_pin27_uart1_tx: rmio-pin27-uart1-tx {
> +                    rockchip,rmio = <27 RMIO_UART1_TX>;

pinmux = <27 << 8 | RMIO_UART1_TX>;

> +++ b/include/dt-bindings/pinctrl/rockchip,rk3506-rmio.h

These number dumps are not appreciated inside the bindings
despite quite a few found their way in there.

Use something like
arch/*/dts/rockchip/rk3506-rmio-pins.dtsi
and include that into your device trees instead.

Yours,
Linus Walleij