BeagleBone Black led trigger DTS

pinctrl_mx_0.dts

/* stripped down sample for triggering a gpio as led by the kernel*/
/* to compile: dtc -O dtb -o BB-MX1-00A0.dtbo -b 0 -@ pinctrl_mx_0.dts */
/dts-v1/;
/plugin/;
 
/ {
    compatible = "ti,beaglebone", "ti,beaglebone-black";
 
        /* identification */
        part-number = "BB-TEST1";
        version = "00A0";
        
        /* declare all pins we use exclusively for us */
        exclusive-use =
            "P9.28";

        
     /* STAT LED configuration part 1*/   
    fragment@2 {
        target = <&am33xx_pinmux>;
        __overlay__ {

            mx_led_pins: pinmux_mx_led_pins {
                pinctrl-single,pins = <
                    0x19c 0x07 /* P9_28 | MODE7 | STAT LED*/
                >;
            };
        };
    };    
        
        
    /* STAT LED configuration part 2*/       
    fragment@3 {
        target = <&ocp>;
        __overlay__ {

            mx_leds {
                compatible = "gpio-leds";
                pinctrl-names = "default";
                pinctrl-0 = <&mx_led_pins>;

                status_led {
                    label = "mx:status_led";
                    gpios = <&gpio4 17 0>;      /* gpio4 is gpio3 */
                    linux,default-trigger = "heartbeat";
                    default-state = "on";
                };
            };
        };
    };
    
    
};