| # SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause |
| %YAML 1.2 |
| --- |
| $id: http://devicetree.org/schemas/w1/w1-uart.yaml# |
| $schema: http://devicetree.org/meta-schemas/core.yaml# |
| |
| title: UART 1-Wire Bus |
| |
| maintainers: |
| - Christoph Winklhofer <cj.winklhofer@gmail.com> |
| |
| description: | |
| UART 1-wire bus. Utilizes the UART interface via the Serial Device Bus |
| to create the 1-Wire timing patterns. |
| |
| The UART peripheral must support full-duplex and operate in open-drain |
| mode. The timing patterns are generated by a specific combination of |
| baud-rate and transmitted byte, which corresponds to a 1-Wire read bit, |
| write bit or reset pulse. |
| |
| The default baud-rate for reset and presence detection is 9600 and for |
| a 1-Wire read or write operation 115200. In case the actual baud-rate |
| is different from the requested one, the transmitted byte is adapted |
| to generate the 1-Wire timing patterns. |
| |
| https://www.analog.com/en/technical-articles/using-a-uart-to-implement-a-1wire-bus-master.html |
| |
| properties: |
| compatible: |
| const: w1-uart |
| |
| reset-bps: |
| default: 9600 |
| description: |
| The baud rate for the 1-Wire reset and presence detect. |
| |
| write-0-bps: |
| default: 115200 |
| description: |
| The baud rate for the 1-Wire write-0 cycle. |
| |
| write-1-bps: |
| default: 115200 |
| description: |
| The baud rate for the 1-Wire write-1 and read cycle. |
| |
| required: |
| - compatible |
| |
| additionalProperties: |
| type: object |
| |
| examples: |
| - | |
| serial { |
| onewire { |
| compatible = "w1-uart"; |
| }; |
| }; |