Re: [PATCH 1/2] dt-bindings: mux-controller: ti: add binding for event mux router

[Alvin Šipraga]

Hi Rahul,

On Fri, Aug 28, 2026 at 03:36:14PM +0530, Rahul Sharma wrote:
> Add binding for the event mux router of TI's K3 based SoC AM62L.

[...]

> +  ti,reg-mask-val:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    items:
> +      items:
> +        - description: Register offset (relative to reg base)
> +        - description: Bit mask for the mux control bits
> +        - description: Value to write when mux is active (state 1)
> +    minItems: 1
> +    description: |
> +      Array of triplets specifying register offset, mask, and value for each
> +      mux control. Each triplet contains:
> +      - register offset (relative to reg base)
> +      - bit mask for the mux control bits
> +      - value to write when mux is active (state 1)

As I understand it, you are creating a binary (0=off / 1=on) mux control
for each reg-mask-val triplet. But couldn't you just use the mmio-mux
binding/driver for this, delegating the value setting to the consumer?

[...]

> +examples:
> +  - |
> +    #include <dt-bindings/mux/mux.h>
> +
> +    // Example 1: TI AM62L GPIO Mux Router
> +    mux-controller@a00000 {
> +        compatible = "ti,am62l-event-mux-router";
> +        reg = <0xa00000 0x400>;
> +        #mux-control-cells = <1>;
> +
> +        /* Mux Register addresses: 0xa00004 + (J × 4) */
> +        /* GPIO0_40 -> BCDMA trigger 15 */
> +        ti,reg-mask-val = <0x40 0x000ff 0x00028>;
> +        idle-states = <0>;
> +    };

Alternatively,

 foo_mux: mux-controller {
   compatible = "mmio-mux";
   reg = <...>;
   #mux-control-cells = <1>;
   mux-reg-masks = <0x40 0x000ff>;
   idle-states = <0>;
 };

 toto-consumer {
   compatible = "toto";
   mux-states = <&foo_mux 0 0x00028>;
   mux-state-names = "gpio-trigger";
 };

What's wrong with that?

Kind regards,
Alvin