Activation of GPIO pins using overlays

Hello there. I'm trying to set up GPIO pins PD15 and PD16 on my OrangePi 3 LTS to work as input pins using device tree overlays. The overlay I have created is the following (for PD15 only):

/dts-v1/;
/plugin/;

/ {
	compatible = "allwinner,sun50i-h6";	

	fragment@0 {
		target = <&pio>;

		__overlay__ {
			my_pins:my_pins {
				pins = "PD15";
				function = "gpio_in";
				default-state = "on";
			};
		};
	};
	
	fragment@1 {
		target-path = "/";
		__overlay__ {
			my@0 {
				compatible = "my-gpio";
				pinctrl-names = "default";
				pinctrl-0 = <&my_pins>;
				gpios = <&pio 3 15 0>;
				status = "okay";
			};
		};
	};	
};

Probably it is incorrect, because when I check the GPIO state using "gpio readall" command, I still get OFF state for the PD15 pin. Of course, I could change the pin mode using the "gpio" command itself (it does work, like "gpio mode 9 in" does set the PD15 pin mode to input), but I would prefer the overlays method.