"simple-audio-card"-based overlay for the WM8731 on RockPi 4

simple-wm8731-overlay.dts

// simple-wm8731-overlay.dts
/dts-v1/;
/plugin/;

/ {

    compatible = "rockchip,rockpi","rockchip,rk3399";

    fragment@0 {
        target = <&i2s1>;
        __overlay__ {
            status = "okay";
        };
    };

    fragment@1 {
        target = <&i2c7>;
        __overlay__ {
            #address-cells = <1>;
            #size-cells = <0>;
            status = "okay";

            wm8731: wm8731@1a {
                #sound-dai-cells = <0>;
                compatible = "wlf,wm8731";
                reg = <0x1a>;
                status = "okay";
            };
        };
    };

    fragment@2 {
        target-path = "/sound-ext-card";
        __overlay__ {
           status = "okay";
           compatible = "simple-audio-card";
           simple-audio-card,format = "i2s";
           simple-audio-card,name = "rockchip,wm8731-codec";
           simple-audio-card,widgets =
              "Microphone", "Mic Jack",
              "Headphone", "Headphone Jack";
           simple-audio-card,routing =
              "Mic Jack", "MICIN",
              "Headphone Jack", "LHPOUT",
              "Headphone Jack", "RHPOUT";
           simple-audio-card,bitclock-master = <&sac_cpu>;
           simple-audio-card,frame-master = <&sac_cpu>;
           sac_cpu: simple-audio-card,cpu {
               sound-dai = <&i2s1>;
//             clocks = <0x57 0x1d5>;
           };
           sac_codec: simple-audio-card,codec {
               sound-dai = <&wm8731>;
           };
       };
   };

};