spi: add DT bindings for UniPhier SPI controller

Add DT bindings for SPI controller implemented in UniPhier SoCs.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/Documentation/devicetree/bindings/spi/spi-uniphier.txt b/Documentation/devicetree/bindings/spi/spi-uniphier.txt
new file mode 100644 (file)
index 0000000..504a4ec
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-uniphier.txt
@@ -0,0 +1,22 @@
+Socionext UniPhier SPI controller driver
+
+UniPhier SoCs have SCSSI which supports SPI single channel.
+
+Required properties:
+ - compatible: should be "socionext,uniphier-scssi"
+ - reg: address and length of the spi master registers
+ - #address-cells: must be <1>, see spi-bus.txt
+ - #size-cells: must be <0>, see spi-bus.txt
+ - clocks: A phandle to the clock for the device.
+ - resets: A phandle to the reset control for the device.
+
+Example:
+
+spi0: spi@54006000 {
+       compatible = "socionext,uniphier-scssi";
+       reg = <0x54006000 0x100>;
+       #address-cells = <1>;
+       #size-cells = <0>;
+       clocks = <&peri_clk 11>;
+       resets = <&peri_rst 11>;
+};