rk serial: add Documentation/devicetree/bindings/serial/rockchip_uart.txt

diff --git a/Documentation/devicetree/bindings/serial/rockchip_uart.txt b/Documentation/devicetree/bindings/serial/rockchip_uart.txt
new file mode 100644 (file)
index 0000000..d8244da
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/rockchip_uart.txt
@@ -0,0 +1,27 @@
+* Universal Asynchronous Receiver/Transmitter (UART)
+
+- compatible: "rockchip,rk_serial"
+
+  Compatibility with all rk28xx rk29xx rk30xx rk31xx SOCs.
+
+- reg: The base address of the UART register bank.
+
+- interrupts: A single interrupt specifier.
+
+- id: port line, determine the ttySx
+ 
+- use-dma-rx: enable dma receive
+
+- use-dma-tx: enable dma tramsmit
+
+Example:
+uart0: serial@10124000 {
+               compatible = "rockchip,rk_serial";
+               reg = <0x10124000 0x100>;
+               interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
+               clock-frequency = <24000000>;
+               id = <0>;
+               use-dma-rx;
+               use-dma-tx;
+               status = "disabled";
+       };