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1* Atmel Universal Synchronous Asynchronous Receiver/Transmitter (USART)
2
3Required properties:
4- compatible: Should be "atmel,<chip>-usart"
5 The compatible <chip> indicated will be the first SoC to support an
6 additional mode or an USART new feature.
7- reg: Should contain registers location and length
8- interrupts: Should contain interrupt
9
10Optional properties:
11- atmel,use-dma-rx: use of PDC or DMA for receiving data
12- atmel,use-dma-tx: use of PDC or DMA for transmitting data
13- add dma bindings for dma transfer:
14 - dmas: DMA specifier, consisting of a phandle to DMA controller node,
15 memory peripheral interface and USART DMA channel ID, FIFO configuration.
16 Refer to dma.txt and atmel-dma.txt for details.
17 - dma-names: "rx" for RX channel, "tx" for TX channel.
18
19<chip> compatible description:
20- at91rm9200: legacy USART support
21- at91sam9260: generic USART implementation for SAM9 SoCs
22
23Example:
24- use PDC:
25 usart0: serial@fff8c000 {
26 compatible = "atmel,at91sam9260-usart";
27 reg = <0xfff8c000 0x4000>;
28 interrupts = <7>;
29 atmel,use-dma-rx;
30 atmel,use-dma-tx;
31 };
32
33- use DMA:
34 usart0: serial@f001c000 {
35 compatible = "atmel,at91sam9260-usart";
36 reg = <0xf001c000 0x100>;
37 interrupts = <12 4 5>;
38 atmel,use-dma-rx;
39 atmel,use-dma-tx;
40 dmas = <&dma0 2 0x3>,
41 <&dma0 2 0x204>;
42 dma-names = "tx", "rx";
43 };