1# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause 2%YAML 1.2 3--- 4$id: http://devicetree.org/schemas/w1/w1-uart.yaml# 5$schema: http://devicetree.org/meta-schemas/core.yaml# 6 7title: UART 1-Wire Bus 8 9maintainers: 10 - Christoph Winklhofer <cj.winklhofer@gmail.com> 11 12description: | 13 UART 1-wire bus. Utilizes the UART interface via the Serial Device Bus 14 to create the 1-Wire timing patterns. 15 16 The UART peripheral must support full-duplex and operate in open-drain 17 mode. The timing patterns are generated by a specific combination of 18 baud-rate and transmitted byte, which corresponds to a 1-Wire read bit, 19 write bit or reset pulse. 20 21 The default baud-rate for reset and presence detection is 9600 and for 22 a 1-Wire read or write operation 115200. In case the actual baud-rate 23 is different from the requested one, the transmitted byte is adapted 24 to generate the 1-Wire timing patterns. 25 26 https://www.analog.com/en/technical-articles/using-a-uart-to-implement-a-1wire-bus-master.html 27 28properties: 29 compatible: 30 const: w1-uart 31 32 reset-bps: 33 default: 9600 34 description: 35 The baud rate for the 1-Wire reset and presence detect. 36 37 write-0-bps: 38 default: 115200 39 description: 40 The baud rate for the 1-Wire write-0 cycle. 41 42 write-1-bps: 43 default: 115200 44 description: 45 The baud rate for the 1-Wire write-1 and read cycle. 46 47required: 48 - compatible 49 50additionalProperties: 51 type: object 52 53examples: 54 - | 55 serial { 56 onewire { 57 compatible = "w1-uart"; 58 }; 59 }; 60