arm64: dts: mediatek: cherry: Enable Elantech eKTH3000 i2c trackpad

The Cherry platform uses an Elantech touchpad/trackpad: enable
probing it at address 0x15 on I2C1.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20220902081156.38526-7-angelogioacchino.delregno@collabora.comSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>

arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi

@@ -134,6 +134,16 @@ &i2c1 {
 	i2c-scl-internal-delay-ns = <12500>;
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c1_pins>;
+
+	trackpad@15 {
+		compatible = "elan,ekth3000";
+		reg = <0x15>;
+		interrupts-extended = <&pio 6 IRQ_TYPE_LEVEL_LOW>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&trackpad_pins>;
+		vcc-supply = <&pp3300_s3>;
+		wakeup-source;
+	};
 };
 
 &i2c2 {
@@ -710,6 +720,14 @@ subpmic_pin_irq: pins-subpmic-int-n {
 		};
 	};
 
+	trackpad_pins: trackpad-default-pins {
+		pins-int-n {
+			pinmux = <PINMUX_GPIO6__FUNC_GPIO6>;
+			input-enable;
+			bias-pull-up;
+		};
+	};
+
 	touchscreen_pins: touchscreen-default-pins {
 		pins-int-n {
 			pinmux = <PINMUX_GPIO92__FUNC_GPIO92>;