arch/arm/boot/dts/bcm2835-rpi-b.dts

/dts-v1/;
#include "bcm2835-rpi.dtsi"

/ {
	compatible = "raspberrypi,model-b", "brcm,bcm2835";
	model = "Raspberry Pi Model B";

	leds {
		act {
			gpios = <&gpio 16 1>;
		};
	};
};

&gpio {
	pinctrl-0 = <&gpioout &alt0 &alt3>;
};