dt-bindings: mfd: Add Altera Arria10 System Resource Chip bindings

The Altera Arria10 Devkit System Resource chip is a Multi-Function
Device with a GPIO expander.

This patch adds documentation for the Altera A10-SR DT bindings.

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

diff --git a/Documentation/devicetree/bindings/mfd/altera-a10sr.txt b/Documentation/devicetree/bindings/mfd/altera-a10sr.txt
new file mode 100644 (file)
index 0000000..ea151f2
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/altera-a10sr.txt
@@ -0,0 +1,46 @@
+* Altera Arria10 Development Kit System Resource Chip
+
+Required parent device properties:
+- compatible           : "altr,a10sr"
+- spi-max-frequency    : Maximum SPI frequency.
+- reg                  : The SPI Chip Select address for the Arria10
+                         System Resource chip
+- interrupt-parent     : The parent interrupt controller.
+- interrupts           : The interrupt line the device is connected to.
+- interrupt-controller : Marks the device node as an interrupt controller.
+- #interrupt-cells     : The number of cells to describe an IRQ, should be 2.
+                           The first cell is the IRQ number.
+                           The second cell is the flags, encoded as trigger
+                           masks from ../interrupt-controller/interrupts.txt.
+
+The A10SR consists of these sub-devices:
+
+Device                   Description
+------                   ----------
+a10sr_gpio               GPIO Controller
+
+Arria10 GPIO
+Required Properties:
+- compatible        : Should be "altr,a10sr-gpio"
+- 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 flags.
+                      See ../gpio/gpio.txt for more information.
+
+Example:
+
+        resource-manager@0 {
+               compatible = "altr,a10sr";
+               reg = <0>;
+               spi-max-frequency = <100000>;
+               interrupt-parent = <&portb>;
+               interrupts = <5 IRQ_TYPE_LEVEL_LOW>;
+               interrupt-controller;
+               #interrupt-cells = <2>;
+
+               a10sr_gpio: gpio-controller {
+                       compatible = "altr,a10sr-gpio";
+                       gpio-controller;
+                       #gpio-cells = <2>;
+               };
+       };