ARM: dts: sun6i: add p2wi controller node to dtsi

The p2wi controller has only one possible pinmux setting. Use it by
default in the dtsi, instead of having to set it in each board's dts.
Signed-off-by: NBoris BREZILLON <boris.brezillon@free-electrons.com>
[wens@csie.org: reformat commit title; rename p2wi pins and use as default]
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun6i-a31.dtsi

@@ -973,6 +973,27 @@
 				allwinner,drive = <SUN4I_PINCTRL_10_MA>;
 				allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
 			};
+
+			p2wi_pins: p2wi {
+				allwinner,pins = "PL0", "PL1";
+				allwinner,function = "s_p2wi";
+				allwinner,drive = <SUN4I_PINCTRL_10_MA>;
+				allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
+			};
+		};
+
+		p2wi: i2c@01f03400 {
+			compatible = "allwinner,sun6i-a31-p2wi";
+			reg = <0x01f03400 0x400>;
+			interrupts = <GIC_SPI 39 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&apb0_gates 3>;
+			clock-frequency = <100000>;
+			resets = <&apb0_rst 3>;
+			pinctrl-names = "default";
+			pinctrl-0 = <&p2wi_pins>;
+			status = "disabled";
+			#address-cells = <1>;
+			#size-cells = <0>;
 		};
 	};
 };