spi: xilinx: Add devicetree binding for spi-xilinx

Add a binding document for the spi/spi-xilinx

Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/Documentation/devicetree/bindings/spi/spi-xilinx.txt b/Documentation/devicetree/bindings/spi/spi-xilinx.txt
new file mode 100644 (file)
index 0000000..c7b7856
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-xilinx.txt
@@ -0,0 +1,22 @@
+Xilinx SPI controller Device Tree Bindings
+-------------------------------------------------
+
+Required properties:
+- compatible           : Should be "xlnx,xps-spi-2.00.a" or "xlnx,xps-spi-2.00.b"
+- reg                  : Physical base address and size of SPI registers map.
+- interrupts           : Property with a value describing the interrupt
+                         number.
+- interrupt-parent     : Must be core interrupt controller
+
+Optional properties:
+- xlnx,num-ss-bits     : Number of chip selects used.
+
+Example:
+       axi_quad_spi@41e00000 {
+                       compatible = "xlnx,xps-spi-2.00.a";
+                       interrupt-parent = <&intc>;
+                       interrupts = <0 31 1>;
+                       reg = <0x41e00000 0x10000>;
+                       xlnx,num-ss-bits = <0x1>;
+       };
+