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+* RS485 serial communications
+
+The RTS signal is capable of automatically controlling line direction for
+the built-in half-duplex mode.
+The properties described hereafter shall be given to a half-duplex capable
+UART node.
+
+Required properties:
+- rs485-rts-delay: prop-encoded-array <a b> where:
+ * a is the delay beteween rts signal and beginning of data sent in milliseconds.
+ it corresponds to the delay before sending data.
+ * b is the delay between end of data sent and rts signal in milliseconds
+ it corresponds to the delay after sending data and actual release of the line.
+
+Optional properties:
+- linux,rs485-enabled-at-boot-time: empty property telling to enable the rs485
+ feature at boot time. It can be disabled later with proper ioctl.
+- rs485-rx-during-tx: empty property that enables the receiving of data even
+ whilst sending data.
+
+RS485 example for Atmel USART:
+ usart0: serial@fff8c000 {
+ compatible = "atmel,at91sam9260-usart";
+ reg = <0xfff8c000 0x4000>;
+ interrupts = <7>;
+ atmel,use-dma-rx;
+ atmel,use-dma-tx;
+ linux,rs485-enabled-at-boot-time;
+ rs485-rts-delay = <0 200>; // in milliseconds
+ };
+