[patch v3 5/5] Documentation: DT bindings AST2500 DMA UART driver

[sudheer.v]

From: sudheer veliseti <sudheer.open at gmail.com>

documentation for Dt bindings for DMA based UARTs in AST2500

Signed-off-by: sudheer veliseti <sudheer.open at gmail.com>
---

Changes in v3:
- change logs added

.../bindings/serial/ast2500-dma-uart.txt      | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/serial/ast2500-dma-uart.txt

diff --git a/Documentation/devicetree/bindings/serial/ast2500-dma-uart.txt b/Documentation/devicetree/bindings/serial/ast2500-dma-uart.txt
new file mode 100644
index 000000000000..6f01ddecba56
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/ast2500-dma-uart.txt
@@ -0,0 +1,40 @@
+
+node for DMA controller:
+                       ast_uart_sdma: uart_sdma at 1e79e000 {
+                               compatible = "aspeed,ast-uart-sdma";
+                               reg = <0x1e79e000 0x400>;
+                               interrupts = <50>;
+                               status = "disabled";
+                       };
+this node  doesn't binds with any driver.
+DMA controller is handled as a separate SW layer,and is included in the same driver.
+This DMA controller node is included in DT just for Register base and interrupt details
+
+
+
+node for DMA-UART :
+
+
+Required properties:
+
+- compatible: "aspeed,ast-sdma-uart"
+- reg: The base address of the UART register bank
+- interrupts: should contain interrupt specifier.
+- clocks: Clock driving the hardware;
+- pinctrl-0 : list of pinconfigurations
+- dma-channel: channel of DMA-controller which is used
+
+Example:
+
+                 dma_uart1: dma_uart1 at 1e783000{
+                          compatible = "aspeed,ast-sdma-uart";
+                          reg = <0x1e783000 0x1000>;
+                          reg-shift = <2>;
+                          interrupts = <9>;
+                          clocks = <&syscon ASPEED_CLK_GATE_UART1CLK>;
+                          dma-channel = <0>;
+                          no-loopback-test;
+                          pinctrl-names = "default";
+                          pinctrl-0 = <&pinctrl_txd1_default &pinctrl_rxd1_default>;
+                          status = "disabled";
+                       };
-- 
2.17.1