gpio: dt-bindings: add brcm,bcm6345-gpio bindings

This patch adds the device tree bindings for the Broadcom's BCM6345
memory-mapped GPIO controllers.

The gpios will be supported by gpio-mmio code of the
GPIO generic library.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/Documentation/devicetree/bindings/gpio/brcm,bcm6345-gpio.txt b/Documentation/devicetree/bindings/gpio/brcm,bcm6345-gpio.txt
new file mode 100644 (file)
index 0000000..e785314
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/brcm,bcm6345-gpio.txt
@@ -0,0 +1,46 @@
+Bindings for the Broadcom's brcm,bcm6345-gpio memory-mapped GPIO controllers.
+
+These bindings can be used on any BCM63xx SoC. However, BCM6338 and BCM6345
+are the only ones which don't need a pinctrl driver.
+BCM6338 have 8-bit data and dirout registers, where GPIO state can be read
+and/or written, and the direction changed from input to output.
+BCM6345 have 16-bit data and dirout registers, where GPIO state can be read
+and/or written, and the direction changed from input to output.
+
+Required properties:
+       - compatible: should be "brcm,bcm6345-gpio"
+       - reg-names: must contain
+               "dat" - data register
+               "dirout" - direction (output) register
+       - reg: address + size pairs describing the GPIO register sets;
+               order must correspond with the order of entries in reg-names
+       - #gpio-cells: must be set to 2. The first cell is the pin number and
+                       the second cell is used to specify the gpio polarity:
+                       0 = active high
+                       1 = active low
+       - gpio-controller: Marks the device node as a gpio controller.
+
+Optional properties:
+       - native-endian: use native endian memory.
+
+Examples:
+       - BCM6338:
+       gpio: gpio-controller@fffe0407 {
+               compatible = "brcm,bcm6345-gpio";
+               reg-names = "dirout", "dat";
+               reg = <0xfffe0407 1>, <0xfffe040f 1>;
+
+               #gpio-cells = <2>;
+               gpio-controller;
+       };
+
+       - BCM6345:
+       gpio: gpio-controller@fffe0406 {
+               compatible = "brcm,bcm6345-gpio";
+               reg-names = "dirout", "dat";
+               reg = <0xfffe0406 2>, <0xfffe040a 2>;
+               native-endian;
+
+               #gpio-cells = <2>;
+               gpio-controller;
+       };