Re: [PATCH v3 6/7] arm64: dts: imx8mp-evk: add board-level mux for CAN2 and MICFIL

[Ahmad Fatoum]

On 3/11/26 8:08 PM, Frank Li wrote:
> The board integrates an on-board mux to route shared signals to either
> CAN2 or PDM (MICFIL). The mux is controlled by a GPIO.
> 
> Add a pinctrl-based multiplexer node to describe this routing and ensure
> proper probe ordering of the dependent devices.
> 
> Previously, MICFIL operation implicitly depended on the default level of
> PCA6416 GPIO3. After adding the pinctrl-multiplexer, make the dependency
> explicit.
> 
> Signed-off-by: Frank Li <Frank.Li@xxxxxxx>

Reviewed-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>

I really like this new abstraction.

> +	can_mux_pinctrl: pinctrl-gpiomux {
> +		compatible = "pinctrl-multiplexer";
> +
> +		can_fun: can-grp {
> +			mux-states = <&can_mux 1>;
> +		};
> +
> +		pdm_fun: pdm-grp {
> +			mux-states = <&can_mux 0>;
> +		};
> +	};

Just to make sure: If both &flexcan2 and &micfil were enabled at the
same time, the existing pinctrl clash detection will also work for this
new pinctrl-multiplexer and point that out, right?

Thanks,
Ahmad

> +
>  	memory@40000000 {
>  		device_type = "memory";
>  		reg = <0x0 0x40000000 0 0xc0000000>,
> @@ -446,7 +465,7 @@ &flexcan1 {
>  
>  &flexcan2 {
>  	pinctrl-names = "default";
> -	pinctrl-0 = <&pinctrl_flexcan2>;
> +	pinctrl-0 = <&pinctrl_flexcan2>, <&can_fun>;
>  	phys = <&flexcan_phy 1>;
>  	status = "disabled";/* can2 pin conflict with pdm */
>  };
> @@ -712,7 +731,7 @@ &lcdif3 {
>  &micfil {
>  	#sound-dai-cells = <0>;
>  	pinctrl-names = "default";
> -	pinctrl-0 = <&pinctrl_pdm>;
> +	pinctrl-0 = <&pinctrl_pdm>, <&pdm_fun>;
>  	assigned-clocks = <&clk IMX8MP_CLK_PDM>;
>  	assigned-clock-parents = <&clk IMX8MP_AUDIO_PLL1_OUT>;
>  	assigned-clock-rates = <196608000>;
> 

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