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# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/i2c/i2c-gpio.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Bindings for GPIO bitbanged I2C

maintainers:
  - Wolfram Sang <wolfram@the-dreams.de>

allOf:
  - $ref: /schemas/i2c/i2c-controller.yaml#

properties:
  compatible:
    items:
      - const: i2c-gpio

  sda-gpios:
    description:
      gpio used for the sda signal, this should be flagged as
      active high using open drain with (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)
      from <dt-bindings/gpio/gpio.h> since the signal is by definition
      open drain.
    maxItems: 1

  scl-gpios:
    description:
      gpio used for the scl signal, this should be flagged as
      active high using open drain with (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)
      from <dt-bindings/gpio/gpio.h> since the signal is by definition
      open drain.
    maxItems: 1

  i2c-gpio,scl-output-only:
    description: scl as output only
    type: boolean

  i2c-gpio,delay-us:
    description: delay between GPIO operations (may depend on each platform)
    $ref: /schemas/types.yaml#/definitions/uint32

  i2c-gpio,timeout-ms:
    description: timeout to get data
    $ref: /schemas/types.yaml#/definitions/uint32

  # Deprecated properties, do not use in new device tree sources:
  gpios:
    minItems: 2
    maxItems: 2
    description: sda and scl gpio, alternative for {sda,scl}-gpios

  i2c-gpio,sda-open-drain:
    # Generate a warning if present
    not: true
    description: this means that something outside of our control has put
      the GPIO line used for SDA into open drain mode, and that something is
      not the GPIO chip. It is essentially an inconsistency flag.

  i2c-gpio,scl-open-drain:
    # Generate a warning if present
    not: true
    description: this means that something outside of our control has put the
      GPIO line used for SCL into open drain mode, and that something is not
      the GPIO chip. It is essentially an inconsistency flag.

required:
  - compatible
  - sda-gpios
  - scl-gpios

...