[PATCH v9 1/2] dt-bindings: input: touchscreen: iqs5xx: Add bindings

[Jeff LaBundy <jeff@labundy.com>]

This patch adds binding documentation for the Azoteq IQS550/572/525
family of trackpad/touchscreen controllers.

Signed-off-by: Jeff LaBundy <jeff@labundy.com>
---
Changes in v9:
  - Corrected the polarity of the reset GPIO in the example node to match that
    of the device's active-low NRST pin
  - Removed previous Reviewed-by trailer as this file has since changed

Changes in v8:
  - Added Reviewed-by trailer

Changes in v7:
  - Removed the azoteq,exp-ver-major and azoteq,exp-ver-minor properties to
    match the driver's updated device identification scheme
  - Updated the example node to use a level-sensitive interrupt rather than
    an edge-sensitive interrupt
  - Removed previous Reviewed-by trailer as this file has since changed

Changes in v6:
  - None

Changes in v5:
  - None

Changes in v4:
  - None

Changes in v3:
  - Added Reviewed-by trailer

Changes in v2:
  - Separated each valid "compatible" property with a line break
  - Specified the polarity of the RDY and NRST pins
  - Replaced duplicate definitions of common touchscreen properties with a
    reference to touchscreen.txt
  - Specified the example node as "touchscreen@74"

 .../bindings/input/touchscreen/iqs5xx.txt          | 80 ++++++++++++++++++++++
 .../devicetree/bindings/vendor-prefixes.txt        |  1 +
 2 files changed, 81 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/touchscreen/iqs5xx.txt

diff --git a/Documentation/devicetree/bindings/input/touchscreen/iqs5xx.txt b/Documentation/devicetree/bindings/input/touchscreen/iqs5xx.txt
new file mode 100644
index 0000000..efa0820
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/iqs5xx.txt
@@ -0,0 +1,80 @@
+Azoteq IQS550/572/525 Trackpad/Touchscreen Controller
+
+Required properties:
+
+- compatible			: Must be equal to one of the following:
+				  "azoteq,iqs550"
+				  "azoteq,iqs572"
+				  "azoteq,iqs525"
+
+- reg				: I2C slave address for the device.
+
+- interrupts			: GPIO to which the device's active-high RDY
+				  output is connected (see [0]).
+
+- reset-gpios			: GPIO to which the device's active-low NRST
+				  input is connected (see [1]).
+
+Optional properties:
+
+- touchscreen-min-x		: See [2].
+
+- touchscreen-min-y		: See [2].
+
+- touchscreen-size-x		: See [2]. If this property is omitted, the
+				  maximum x-coordinate is specified by the
+				  device's "X Resolution" register.
+
+- touchscreen-size-y		: See [2]. If this property is omitted, the
+				  maximum y-coordinate is specified by the
+				  device's "Y Resolution" register.
+
+- touchscreen-max-pressure	: See [2]. Pressure is expressed as the sum of
+				  the deltas across all channels impacted by a
+				  touch event. A channel's delta is calculated
+				  as its count value minus a reference, where
+				  the count value is inversely proportional to
+				  the channel's capacitance.
+
+- touchscreen-fuzz-x		: See [2].
+
+- touchscreen-fuzz-y		: See [2].
+
+- touchscreen-fuzz-pressure	: See [2].
+
+- touchscreen-inverted-x	: See [2]. Inversion is applied relative to that
+				  which may already be specified by the device's
+				  FLIP_X and FLIP_Y register fields.
+
+- touchscreen-inverted-y	: See [2]. Inversion is applied relative to that
+				  which may already be specified by the device's
+				  FLIP_X and FLIP_Y register fields.
+
+- touchscreen-swapped-x-y	: See [2]. Swapping is applied relative to that
+				  which may already be specified by the device's
+				  SWITCH_XY_AXIS register field.
+
+[0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+[1]: Documentation/devicetree/bindings/gpio/gpio.txt
+[2]: Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
+
+Example:
+
+	&i2c1 {
+		/* ... */
+
+		touchscreen@74 {
+			compatible = "azoteq,iqs550";
+			reg = <0x74>;
+			interrupt-parent = <&gpio>;
+			interrupts = <17 4>;
+			reset-gpios = <&gpio 27 1>;
+
+			touchscreen-size-x = <640>;
+			touchscreen-size-y = <480>;
+
+			touchscreen-max-pressure = <16000>;
+		};
+
+		/* ... */
+	};
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index 4b1a2a8..51f9954 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -53,6 +53,7 @@ avic	Shanghai AVIC Optoelectronics Co., Ltd.
 avnet	Avnet, Inc.
 axentia	Axentia Technologies AB
 axis	Axis Communications AB
+azoteq	Azoteq (Pty) Ltd
 bananapi BIPAI KEJI LIMITED
 bhf	Beckhoff Automation GmbH & Co. KG
 bitmain	Bitmain Technologies
--
2.7.4