dt-bindings: serial: Add Milbeaut serial driver description

Add DT bindings document for Milbeaut serial driver.

Signed-off-by: Sugaya Taichi <sugaya.taichi@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/serial/milbeaut-uart.txt b/Documentation/devicetree/bindings/serial/milbeaut-uart.txt
new file mode 100644 (file)
index 0000000..3d2fb1a
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/milbeaut-uart.txt
@@ -0,0 +1,21 @@
+Socionext Milbeaut UART controller
+
+Required properties:
+- compatible: should be "socionext,milbeaut-usio-uart".
+- reg: offset and length of the register set for the device.
+- interrupts: two interrupts specifier.
+- interrupt-names: should be "rx", "tx".
+- clocks: phandle to the input clock.
+
+Optional properties:
+- auto-flow-control: flow control enable.
+
+Example:
+       usio1: usio_uart@1e700010 {
+               compatible = "socionext,milbeaut-usio-uart";
+               reg = <0x1e700010 0x10>;
+               interrupts = <0 141 0x4>, <0 149 0x4>;
+               interrupt-names = "rx", "tx";
+               clocks = <&clk 2>;
+               auto-flow-control;
+       };