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diff --git a/dts/Bindings/serial/atmel-usart.txt b/dts/Bindings/serial/atmel-usart.txt
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+* Atmel Universal Synchronous Asynchronous Receiver/Transmitter (USART)
+
+Required properties:
+- compatible: Should be "atmel,<chip>-usart"
+  The compatible <chip> indicated will be the first SoC to support an
+  additional mode or an USART new feature.
+- reg: Should contain registers location and length
+- interrupts: Should contain interrupt
+- clock-names: tuple listing input clock names.
+	Required elements: "usart"
+- clocks: phandles to input clocks.
+
+Optional properties:
+- atmel,use-dma-rx: use of PDC or DMA for receiving data
+- atmel,use-dma-tx: use of PDC or DMA for transmitting data
+- rts-gpios: specify a GPIO for RTS line. It will use specified PIO instead of the peripheral
+  function pin for the USART RTS feature. If unsure, don't specify this property.
+- add dma bindings for dma transfer:
+	- dmas: DMA specifier, consisting of a phandle to DMA controller node,
+		memory peripheral interface and USART DMA channel ID, FIFO configuration.
+		Refer to dma.txt and atmel-dma.txt for details.
+	- dma-names: "rx" for RX channel, "tx" for TX channel.
+
+<chip> compatible description:
+- at91rm9200:  legacy USART support
+- at91sam9260: generic USART implementation for SAM9 SoCs
+
+Example:
+- use PDC:
+	usart0: serial@fff8c000 {
+		compatible = "atmel,at91sam9260-usart";
+		reg = <0xfff8c000 0x4000>;
+		interrupts = <7>;
+		clocks = <&usart0_clk>;
+		clock-names = "usart";
+		atmel,use-dma-rx;
+		atmel,use-dma-tx;
+		rts-gpios = <&pioD 15 0>;
+	};
+
+- use DMA:
+	usart0: serial@f001c000 {
+		compatible = "atmel,at91sam9260-usart";
+		reg = <0xf001c000 0x100>;
+		interrupts = <12 4 5>;
+		clocks = <&usart0_clk>;
+		clock-names = "usart";
+		atmel,use-dma-rx;
+		atmel,use-dma-tx;
+		dmas = <&dma0 2 0x3>,
+		       <&dma0 2 0x204>;
+		dma-names = "tx", "rx";
+	};