ARM: dts: Add trackpad to exynos5250-spring

The HP Chromebook 11 uses an Atmel maXTouch as trackpad.
The keymap was found by trial-and-error.
Signed-off-by: Andreas Faerber <afaerber@suse.de>
Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/boot/dts/exynos5250-spring.dts

@@ -330,6 +330,22 @@ &i2c_1 {
 	status = "okay";
 	samsung,i2c-sda-delay = <100>;
 	samsung,i2c-max-bus-freq = <378000>;
+
+	trackpad@4b {
+		compatible = "atmel,maxtouch";
+		reg = <0x4b>;
+		interrupt-parent = <&gpx1>;
+		interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&trackpad_irq>;
+		linux,gpio-keymap = <KEY_RESERVED
+				     KEY_RESERVED
+				     KEY_RESERVED
+				     KEY_RESERVED
+				     KEY_RESERVED
+				     BTN_LEFT>;
+		wakeup-source;
+	};
 };
 
 /*
@@ -465,6 +481,13 @@ dp_hpd_gpio: dp-hpd-gpio {
 		samsung,pin-drv = <0>;
 	};
 
+	trackpad_irq: trackpad-irq {
+		samsung,pins = "gpx1-2";
+		samsung,pin-function = <0xf>;
+		samsung,pin-pud = <0>;
+		samsung,pin-drv = <0>;
+	};
+
 	power_key_irq: power-key-irq {
 		samsung,pins = "gpx1-3";
 		samsung,pin-function = <0>;