aboutsummaryrefslogtreecommitdiff
path: root/Documentation/devicetree/bindings/serial/of-serial.txt
blob: 77054772a8f4fe46cb57ba461544e8de606d337c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
* UART (Universal Asynchronous Receiver/Transmitter)

Required properties:
- compatible : one of:
	- "ns8250"
	- "ns16450"
	- "ns16550a"
	- "ns16550"
	- "ns16750"
	- "ns16850"
	- "nvidia,tegra20-uart"
	- "nxp,lpc3220-uart"
	- "ibm,qpace-nwp-serial"
	- "altr,16550-FIFO32"
	- "altr,16550-FIFO64"
	- "altr,16550-FIFO128"
	- "serial" if the port type is unknown.
- reg : offset and length of the register set for the device.
- interrupts : should contain uart interrupt.
- clock-frequency : the input clock frequency for the UART
	 or
  clocks phandle to refer to the clk used as per Documentation/devicetree
  /bindings/clock/clock-bindings.txt

Optional properties:
- current-speed : the current active speed of the UART.
- reg-offset : offset to apply to the mapbase from the start of the registers.
- reg-shift : quantity to shift the register offsets by.
- reg-io-width : the size (in bytes) of the IO accesses that should be
  performed on the device.  There are some systems that require 32-bit
  accesses to the UART (e.g. TI davinci).
- used-by-rtas : set to indicate that the port is in use by the OpenFirmware
  RTAS and should not be registered.
- no-loopback-test: set to indicate that the port does not implements loopback
  test mode
- fifo-size: the fifo size of the UART.
- auto-flow-control: one way to enable automatic flow control support. The
  driver is allowed to detect support for the capability even without this
  property.
- has-hw-flow-control: the hardware has flow control capability.

Example:

	uart@80230000 {
		compatible = "ns8250";
		reg = <0x80230000 0x100>;
		clock-frequency = <3686400>;
		interrupts = <10>;
		reg-shift = <2>;
	};