Based on kernel version 3.11. Page generated on 2013-09-03 22:55 EST.
1 * UART (Universal Asynchronous Receiver/Transmitter) 2 3 Required properties: 4 - compatible : one of: 5 - "ns8250" 6 - "ns16450" 7 - "ns16550a" 8 - "ns16550" 9 - "ns16750" 10 - "ns16850" 11 - "nvidia,tegra20-uart" 12 - "nxp,lpc3220-uart" 13 - "ibm,qpace-nwp-serial" 14 - "altr,16550-FIFO32" 15 - "altr,16550-FIFO64" 16 - "altr,16550-FIFO128" 17 - "serial" if the port type is unknown. 18 - reg : offset and length of the register set for the device. 19 - interrupts : should contain uart interrupt. 20 - clock-frequency : the input clock frequency for the UART 21 or 22 clocks phandle to refer to the clk used as per Documentation/devicetree 23 /bindings/clock/clock-bindings.txt 24 25 Optional properties: 26 - current-speed : the current active speed of the UART. 27 - reg-offset : offset to apply to the mapbase from the start of the registers. 28 - reg-shift : quantity to shift the register offsets by. 29 - reg-io-width : the size (in bytes) of the IO accesses that should be 30 performed on the device. There are some systems that require 32-bit 31 accesses to the UART (e.g. TI davinci). 32 - used-by-rtas : set to indicate that the port is in use by the OpenFirmware 33 RTAS and should not be registered. 34 - no-loopback-test: set to indicate that the port does not implements loopback 35 test mode 36 - fifo-size: the fifo size of the UART. 37 - auto-flow-control: one way to enable automatic flow control support. The 38 driver is allowed to detect support for the capability even without this 39 property. 40 41 Example: 42 43 uart@80230000 { 44 compatible = "ns8250"; 45 reg = <0x80230000 0x100>; 46 clock-frequency = <3686400>; 47 interrupts = <10>; 48 reg-shift = <2>; 49 };