xref: /freebsd/sys/contrib/device-tree/Bindings/serial/fsl-lpuart.txt (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
1* Freescale low power universal asynchronous receiver/transmitter (lpuart)
2
3Required properties:
4- compatible :
5  - "fsl,vf610-lpuart" for lpuart compatible with the one integrated
6    on Vybrid vf610 SoC with 8-bit register organization
7  - "fsl,ls1021a-lpuart" for lpuart compatible with the one integrated
8    on LS1021A SoC with 32-bit big-endian register organization
9  - "fsl,ls1028a-lpuart" for lpuart compatible with the one integrated
10    on LS1028A SoC with 32-bit little-endian register organization
11  - "fsl,imx7ulp-lpuart" for lpuart compatible with the one integrated
12    on i.MX7ULP SoC with 32-bit little-endian register organization
13  - "fsl,imx8qxp-lpuart" for lpuart compatible with the one integrated
14    on i.MX8QXP SoC with 32-bit little-endian register organization
15  - "fsl,imx8qm-lpuart" for lpuart compatible with the one integrated
16    on i.MX8QM SoC with 32-bit little-endian register organization
17- reg : Address and length of the register set for the device
18- interrupts : Should contain uart interrupt
19- clocks : phandle + clock specifier pairs, one for each entry in clock-names
20- clock-names : For vf610/ls1021a/ls1028a/imx7ulp, "ipg" clock is for uart
21  bus/baud clock. For imx8qxp lpuart, "ipg" clock is bus clock that is used
22  to access lpuart controller registers, it also requires "baud" clock for
23  module to receive/transmit data.
24
25Optional properties:
26- dmas: A list of two dma specifiers, one for each entry in dma-names.
27- dma-names: should contain "tx" and "rx".
28- rs485-rts-active-low, linux,rs485-enabled-at-boot-time: see rs485.txt
29
30Note: Optional properties for DMA support. Write them both or both not.
31
32Example:
33
34uart0: serial@40027000 {
35		compatible = "fsl,vf610-lpuart";
36		reg = <0x40027000 0x1000>;
37		interrupts = <0 61 0x00>;
38		clocks = <&clks VF610_CLK_UART0>;
39		clock-names = "ipg";
40		dmas = <&edma0 0 2>,
41			<&edma0 0 3>;
42		dma-names = "rx","tx";
43	};
44