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authorSascha Hauer <s.hauer@pengutronix.de>2014-04-25 11:22:32 +0200
committerSascha Hauer <s.hauer@pengutronix.de>2014-04-28 09:08:46 +0200
commit00ce25c6dcdae5582ae4be37147ab33678adc995 (patch)
tree41c93102ae304a61738c31353e3cb5336ef0b297 /dts/Bindings/serial/atmel-usart.txt
parent0af79fbb6779921d3f1962773adb7fb57d3c89d4 (diff)
downloadbarebox-00ce25c6dcdae5582ae4be37147ab33678adc995.tar.gz
barebox-00ce25c6dcdae5582ae4be37147ab33678adc995.tar.xz
Add devicetree source files as of Linux-3.15-rc2
This adds the Linux dts files to barebox. The dts files are generated from Ian Campbells device-tree-rebasing.git: git://xenbits.xen.org/people/ianc/device-tree-rebasing.git The dts are found in dts/ in the barebox repository and will be updated from upstream regularly, probably for each upstream -rc. To keep the synchronization with upstream easy no changes to the original files are allowed under dts/. Instead changes to upstream dts files will be done using overlays in arch/$ARCH/dts/. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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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";
+ };