dts/bindings/serial/st,stm32-uart-base.yaml

# Copyright (c) 2020 STMICROELECTRONICS
# SPDX-License-Identifier: Apache-2.0

# Common fields for STM32 UART peripherals.
description: STM32 UART-BASE

include:
  - name: uart-controller.yaml
    property-blocklist:
      - clock-frequency
  - name: pinctrl-device.yaml
  - name: reset-device.yaml
  - name: uart-controller-pin-inversion.yaml

properties:
  reg:
    required: true

  clocks:
    required: true

  resets:
    required: true

  interrupts:
    required: true

  current-speed:
    description: |
      Initial baud rate setting for UART. Defaults to standard baudrate of 115200 if not specified.
    default: 115200

  stop-bits:
    description: |
      Sets the number of stop bits. Defaults to standard of 1 if not specified.
    default: "1"

  data-bits:
    description: |
      Sets the number of data bits. Defaults to standard of 8 if not specified.
    default: 8

  single-wire:
    type: boolean
    description: |
      Enable the single wire half-duplex communication.
      Using this mode, TX and RX lines are internally connected and
      only TX pin is used afterwards and should be configured.
      RX/TX conflicts must be handled on user side.

  tx-rx-swap:
    type: boolean
    description:
      Swap the TX and RX pins. Used in case of a cross wired connection.

  pinctrl-0:
    required: true

  pinctrl-names:
    required: true

  wakeup-line:
    type: int
    description: |
      EXTI line number matching the device wakeup interrupt mask register.
      This property is required on stm32 devices where the wakeup interrupt signal could be
      configured masked at boot (sm32wl55 for instance), preventing the device to wakeup
      the core from stop mode(s).
      Valid range: 0 - 31

  de-enable:
    type: boolean
    description: |
      Enable activating an external transeiver through the DE pin which must also be configured
      using pinctrl.

  de-assert-time:
    type: int
    default: 0
    description: |
      Defines the time between the activation of the DE signal and the beginning of the start bit.
      It is expressed in 16th of a bit time.
      Valid range: 0 - 31

  de-deassert-time:
    type: int
    default: 0
    description: |
      Defines the time between the end of the stop bit and the deactivation of the DE signal.
      It is expressed in 16th of a bit time.
      Valid range: 0 - 31

  de-invert:
    type: boolean
    description: |
      Invert the binary logic of the de pin. When enabled, physical logic levels are inverted and
      we use 1=Low, 0=High instead of 1=High, 0=Low.

  fifo-enable:
    type: boolean
    description: |
      Enables transmit and receive FIFO using default FIFO configuration (typically threshold is
      set to 1/8).
      In TX, FIFO allows to work in burst mode, easing scheduling of loaded applications. It also
      allows more reliable communication with UART devices sensitive to variation of inter-frames
      delays.
      In RX, FIFO reduces overrun occurrences.