dtoverlays: Add overlay for Ilitek-ts-i2c driver (213X/23XX/25XX chips)

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

Author: 6by9

arch/arm/boot/dts/overlays/Makefile

@@ -131,6 +131,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
 	i2s-dac.dtbo \
 	i2s-gpio28-31.dtbo \
 	i2s-master-dac.dtbo \
+	ilitek-ts-i2c.dtbo \
 	ilitek251x.dtbo \
 	imx219.dtbo \
 	imx258.dtbo \

arch/arm/boot/dts/overlays/README

@@ -2778,6 +2778,16 @@ Load:   dtoverlay=i2s-master-dac
 Params: <None>
 
 
+Name:   ilitek-ts-i2c
+Info:   Enables I2C connected Ilitek 23XX, 25XX, and 213X touch controllers
+        using GPIO 4 (pin 7 on GPIO header) for interrupt.
+Load:   dtoverlay=ilitek-ts-i2c,<param>=<val>
+Params: interrupt               GPIO used for interrupt (default 4)
+        invx                    Touchscreen inverted x axis
+        invy                    Touchscreen inverted y axis
+        i2c-path                Override I2C path to allow for i2c-gpio buses
+
+
 Name:   ilitek251x
 Info:   Enables I2C connected Ilitek 251x multiple touch controller using
         GPIO 4 (pin 7 on GPIO header) for interrupt.

arch/arm/boot/dts/overlays/ilitek-ts-i2c-overlay.dts

@@ -0,0 +1,60 @@
+// Device tree overlay for I2C connected Ilitek multiple touch controller
+/dts-v1/;
+/plugin/;
+
+/ {
+	compatible = "brcm,bcm2835";
+
+	fragment@0 {
+		target = <&gpio>;
+		__overlay__ {
+			ili2130_pins: ili2130_pins {
+				brcm,pins = <4>; // interrupt
+				brcm,function = <0>; // in
+				brcm,pull = <2>; // pull-up //
+			};
+		};
+	};
+
+	frag1: fragment@1 {
+		target = <&i2c1>;
+		__overlay__ {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "okay";
+
+			ili2130: ili2130@41 {
+				compatible = "ilitek,ili2130";
+				reg = <0x41>;
+				pinctrl-names = "default";
+				pinctrl-0 = <&ili2130_pins>;
+				interrupt-parent = <&gpio>;
+				interrupts = <4 8>; // high-to-low edge triggered
+			};
+		};
+	};
+
+	fragment@2 {
+		target = <&ft5406>;
+		__overlay__ {
+			touchscreen-inverted-x;
+		};
+	};
+
+	fragment@3 {
+		target = <&ft5406>;
+		__overlay__ {
+			touchscreen-inverted-y;
+		};
+	};
+
+	__overrides__ {
+		interrupt = <&ili2130_pins>,"brcm,pins:0",
+			<&ili2130>,"interrupts:0";
+		i2c-path = <&frag1>, "target?=0",
+			   <&frag1>, "target-path";
+		invx = <0>, "-2";
+		invy = <0>, "-3";
+		swapxy = <&ili2130>,"touchscreen-swapped-x-y?";
+	};
+};