zephyr/dts/bindings/dac/espressif,esp32-dac.yaml

# Copyright (c) 2022 Espressif Systems (Shanghai) Co., Ltd.
# SPDX-License-Identifier: Apache-2.0

description: |
    Espressif Digital to Analog converter (DAC) control node
    is part of the RTC low-power domain and belongs to the SENSE
    peripherals set. RTC peripherals has GPIOs controlled by the
    RTCIO mux, which is separated from the main IO mux.

    Two GPIO pads can only be connected to the DAC peripheral.

    ESP32 pads
      - GPIO25 as DAC channel 1
      - GPIO26 as DAC channel 2

    ESP32-S2 pads
      - GPIO17 as DAC channel 1
      - GPIO18 as DAC channel 2

    To enable the DAC peripheral it must be enabled in the board
    dts, or in subsequent overlay file.

          &dac {
              status = "okay";
          };

    To specify the DAC channel to use, dts overlay must include
    properties 'dac-channel-id', which uses zero based channel index.
    Variable 'dac-resolution' must be also specified, although ESP32
    only supported resolution is 8bits.

          / {
            zephyr,user {
              dac = <&dac>;
              dac-channel-id = <0>;
              dac-resolution = <8>;
            };
          };

    NOTE: The DAC peripheral outputs are fixed to gpio pads, therefore
          it does not need to be controlled by the pinctrl node.

compatible: "espressif,esp32-dac"

include: [dac-controller.yaml]

properties:

  "#io-channel-cells":
    const: 1

io-channel-cells:
  - output