[PATCH 7/8] gpio: 74x164: dts: Add documentation for the dt binding

[maxime.ripard@free-electrons.com (Maxime Ripard)]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 .../devicetree/bindings/gpio/gpio-74x164.txt       |   26 ++++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/gpio-74x164.txt

diff --git a/Documentation/devicetree/bindings/gpio/gpio-74x164.txt b/Documentation/devicetree/bindings/gpio/gpio-74x164.txt
new file mode 100644
index 0000000..e2a40a5
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-74x164.txt
@@ -0,0 +1,26 @@
+* Generic 8-bits shift register GPIO driver
+
+Required properties:
+- compatible : Should be "fairchild,74hc595"
+- reg : chip select number
+- gpio-controller : Marks the device node as a gpio controller.
+- #gpio-cells : Should be two.  The first cell is the pin number and
+  the second cell is used to specify the gpio polarity:
+      0 = active high
+      1 = active low
+- register-number: Number of daisy-chained shift registers
+- output-latch-gpio: GPIO connected to the output pin of the registers
+
+Optional properties:
+- latch-active-low: If the output pin is active low
+
+Example:
+
+gpio5: gpio5 at 0 {
+	compatible = "fairchild,74hc595";
+	gpio-controller;
+	#gpio-cells = <2>;
+	registers-number = <4>;
+	output-latch-gpio = <&gpio0 26 0>;
+	spi-max-frequency = <100000>;
+};
-- 
1.7.9.5