dt-bindings: input: add bindings document for ar1021_i2c driver

Add a simple binding document describing the supported devices and the
I2C bus address.

Signed-off-by: Martin Kepplinger <martin.kepplinger@ginzinger.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/Documentation/devicetree/bindings/input/touchscreen/ar1021.txt b/Documentation/devicetree/bindings/input/touchscreen/ar1021.txt
new file mode 100644 (file)
index 0000000..e459e85
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/ar1021.txt
@@ -0,0 +1,16 @@
+* Microchip AR1020 and AR1021 touchscreen interface (I2C)
+
+Required properties:
+- compatible           : "microchip,ar1021-i2c"
+- reg                  : I2C slave address
+- interrupt-parent     : the phandle for the interrupt controller
+- interrupts           : touch controller interrupt
+
+Example:
+
+       touchscreen@4d {
+               compatible = "microchip,ar1021-i2c";
+               reg = <0x4d>;
+               interrupt-parent = <&gpio3>;
+               interrupts = <11 IRQ_TYPE_LEVEL_HIGH>;
+       };