overlays: Add apds9960 overlay

Add an overlay for the AVAGO APDS9960 digital proximity, ambient light, rgb and gesture sensor.
Also update overlay README and Makefile.

Signed-off-by: Michael Kaplan <m.kaplan@evva.com>

arch/arm/boot/dts/overlays/Makefile

@@ -15,6 +15,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
 	allo-katana-dac-audio.dtbo \
 	allo-piano-dac-pcm512x-audio.dtbo \
 	allo-piano-dac-plus-pcm512x-audio.dtbo \
+	apds9960.dtbo \
 	applepi-dac.dtbo \
 	at86rf233.dtbo \
 	audioinjector-addons.dtbo \

arch/arm/boot/dts/overlays/README

@@ -441,6 +441,14 @@ Params: 24db_digital_gain       Allow gain to be applied via the PCM512x codec
                                 better voice quality. (default Off)
 
 
+Name:   apds9960
+Info:   Configures the AVAGO APDS9960 digital proximity, ambient light, RGB and
+        gesture sensor
+Load:   dtoverlay=apds9960,<param>=<val>
+Params: gpiopin                 GPIO used for INT (default 4)
+        noints                  Disable the interrupt GPIO line.
+
+
 Name:   applepi-dac
 Info:   Configures the Orchard Audio ApplePi-DAC audio card
 Load:   dtoverlay=applepi-dac

arch/arm/boot/dts/overlays/apds9960-overlay.dts

@@ -0,0 +1,57 @@
+// Definitions for APDS-9960 ambient light and gesture sensor
+
+/dts-v1/;
+/plugin/;
+
+/ {
+	compatible = "brcm,bcm2835";
+
+	fragment@0 {
+		target = <&i2c1>;
+		__overlay__ {
+			status = "okay";
+		};
+	};
+
+	fragment@1 {
+		target = <&gpio>;
+		__overlay__ {
+			apds9960_pins: apds9960_pins@39 {
+				brcm,pins = <4>;
+				brcm,function = <0>;
+			};
+		};
+	};
+
+	fragment@2 {
+		target = <&i2c1>;
+		__overlay__ {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			apds9960: apds@39 {
+				compatible = "avago,apds9960";
+				reg = <0x39>;
+				status = "okay";
+			};
+		};
+	};
+
+	fragment@3 {
+		target = <&i2c1>;
+		__overlay__ {
+			apds9960_irq: apds@39 {
+				#interrupt-cells=<2>;
+				interrupt-parent = <&gpio>;
+				interrupts = <4 1>;
+			};
+		};
+	};
+
+	__overrides__ {
+		gpiopin = <&apds9960_pins>,"brcm,pins:0",
+				<&apds9960_irq>,"interrupts:0";
+		noints = <0>,"!1!3";
+	};
+};
+