Re: [RFC PATCH 1/2] devicetree: bindings: mux: reg-mux: Update bindings for reg-mux for new property

[Andrew Davis <afd@ti.com>]

On 2/27/25 2:22 PM, Chintan Vankar wrote:
> DT-binding of reg-mux is defined in such a way that one need to provide
> register offset and mask in a "mux-reg-masks" property and corresponding
> register value in "idle-states" property. This constraint forces to define
> these values in such a way that "mux-reg-masks" and "idle-states" must be
> in sync with each other. This implementation would be more complex if
> specific register or set of registers need to be configured which has
> large memory space. Introduce a new property "mux-reg-masks-state" which
> allow to specify offset, mask and value as a tuple in a single property.
> 
> Signed-off-by: Chintan Vankar <c-vankar@ti.com>
> ---
>   .../devicetree/bindings/mux/reg-mux.yaml      | 29 +++++++++++++++++--
>   1 file changed, 27 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/mux/reg-mux.yaml b/Documentation/devicetree/bindings/mux/reg-mux.yaml
> index dc4be092fc2f..a73c5efcf860 100644
> --- a/Documentation/devicetree/bindings/mux/reg-mux.yaml
> +++ b/Documentation/devicetree/bindings/mux/reg-mux.yaml
> @@ -32,11 +32,36 @@ properties:
>           - description: pre-shifted bitfield mask
>       description: Each entry pair describes a single mux control.
>   
> -  idle-states: true
> +  idle-states:
> +    description: Each entry describes mux register state.
> +
> +  mux-reg-masks-state:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    items:
> +      items:
> +        - description: register offset
> +        - description: pre-shifted bitfield mask
> +        - description: register value to be set
> +    description: This property is an extension of mux-reg-masks which
> +                 allows specifying register offset, mask and register
> +                 value to be set in a single property.
> +
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - reg-mux
> +              - mmio-mux

These are the only two possible compatibles, is this "if" check needed?

> +    then:
> +      properties:
> +        mux-reg-masks: true
> +        mux-reg-masks-state: true

You need one, but cannot have both, right? There should be some
way to describe that.

Also an example added below would be good.

Andrew

> +      maxItems: 1
>   
>   required:
>     - compatible
> -  - mux-reg-masks
>     - '#mux-control-cells'
>   
>   additionalProperties: false