ARM: sun5i: chip: add a node for the w1 gpio controller

The CHIP uses a 1-Wire bus to discover the DIPs. Enable the bus in the DT.
Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun5i-r8-chip.dts

@@ -81,6 +81,13 @@ mmc0_pwrseq: mmc0_pwrseq {
 		pinctrl-0 = <&chip_wifi_reg_on_pin>;
 		reset-gpios = <&pio 2 19 GPIO_ACTIVE_LOW>; /* PC19 */
 	};
+
+	onewire {
+		compatible = "w1-gpio";
+		gpios = <&pio 3 2 GPIO_ACTIVE_HIGH>; /* PD2 */
+		pinctrl-names = "default";
+		pinctrl-0 = <&chip_w1_pin>;
+	};
 };
 
 &be0 {
@@ -181,6 +188,13 @@ chip_id_det_pin: chip_id_det_pin@0 {
 		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
 		allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
 	};
+
+	chip_w1_pin: chip_w1_pin@0 {
+		allwinner,pins = "PD2";
+		allwinner,function = "gpio_in";
+	        allwinner,drive = <SUN4I_PINCTRL_10_MA>;
+	        allwinner,pull = <SUN4I_PINCTRL_PULL_UP>;
+	};
 };
 
 &reg_dcdc2 {