spi: spi-gpio: Add DT bindings

This patch adds DT bindings to the spi-gpio driver and some
documentation about how to use it.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/spi/spi-gpio.txt b/Documentation/devicetree/bindings/spi/spi-gpio.txt
new file mode 100644
index 000000000000..8a824be15754
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-gpio.txt
@@ -0,0 +1,29 @@
+SPI-GPIO devicetree bindings
+
+Required properties:
+
+ - compatible: should be set to "spi-gpio"
+ - #address-cells: should be set to <0x1>
+ - ranges
+ - gpio-sck: GPIO spec for the SCK line to use
+ - gpio-miso: GPIO spec for the MISO line to use
+ - gpio-mosi: GPIO spec for the MOSI line to use
+ - cs-gpios: GPIOs to use for chipselect lines
+ - num-chipselects: number of chipselect lines
+
+Example:
+
+        spi {
+                compatible = "spi-gpio";
+                #address-cells = <0x1>;
+                ranges;
+
+                gpio-sck = <&gpio 95 0>;
+                gpio-miso = <&gpio 98 0>;
+                gpio-mosi = <&gpio 97 0>;
+                cs-gpios = <&gpio 125 0>;
+                num-chipselects = <1>;
+
+                /* clients */
+        };
+