Commit a00bb94c authored by Heiner Kallweit's avatar Heiner Kallweit Committed by Wolfram Sang
Browse files

dt-bindings: i2c: gpio: Add properties for dealing with write-only SDA/SCL w/o pullup 



There are slave devices that understand I2C but have read-only SDA and
SCL. Examples are FD650 7-segment LED controller and its derivatives.
Typical board designs don't even have a pull-up for both pins.
Therefore add properties for not using open-drain. For write-only SCL
we have a property already, add one for write-only SDA.

Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: default avatarRob Herring <robh@kernel.org>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent f531ecf7

Documentation/devicetree/bindings/i2c/i2c-gpio.yaml

+26 −0
Original line number Diff line number Diff line
@@ -33,6 +33,10 @@ properties: 
      open drain.

    maxItems: 1



  i2c-gpio,sda-output-only:

    description: sda as output only

    type: boolean



  i2c-gpio,scl-output-only:

    description: scl as output only

    type: boolean
@@ -63,6 +67,28 @@ properties: 
      GPIO line used for SCL into open drain mode, and that something is not

      the GPIO chip. It is essentially an inconsistency flag.



  i2c-gpio,sda-has-no-pullup:

    type: boolean

    description: sda is used in a non-compliant way and has no pull-up.

      Therefore disable open-drain. This property is mutually-exclusive

      with i2c-gpio,sda-open-drain.



  i2c-gpio,scl-has-no-pullup:

    type: boolean

    description: scl is used in a non-compliant way and has no pull-up.

      Therefore disable open-drain. This property is mutually-exclusive

      with i2c-gpio,scl-open-drain.



dependencies:

  i2c-gpio,sda-has-no-pullup:

    not:

      required:

        - i2c-gpio,sda-open-drain

  i2c-gpio,scl-has-no-pullup:

    not:

      required:

        - i2c-gpio,scl-open-drain



required:

  - compatible

  - sda-gpios