Commit 241a952f authored by Oleksij Rempel's avatar Oleksij Rempel Committed by Dmitry Torokhov
Browse files

dt-bindings: touchscreen: resistive-adc-touch: add support for z1 and z2 channels 



For pressure calculation based on plates resistance we need some additional
properties:
- z1 and z2 channels with additional measurements between plates
- actual resistance of the touchscreen. Currently we use only
  X-resistance.

Signed-off-by: default avatarOleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: default avatarRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210525054634.9134-4-o.rempel@pengutronix.de


Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
parent ff7af0fe

Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml

+16 −0
Original line number Diff line number Diff line
@@ -27,6 +27,8 @@ properties: 
      - description: x

      - description: y

      - description: pressure (optional)

      - description: z1 (optional)

      - description: z2 (optional)



  io-channel-names:

    oneOf:
@@ -37,6 +39,11 @@ properties: 
          - enum: [x, y, pressure]

          - enum: [x, y, pressure]

          - enum: [x, y, pressure]

      - items:

          - enum: [x, y, z1, z2]

          - enum: [x, y, z1, z2]

          - enum: [x, y, z1, z2]

          - enum: [x, y, z1, z2]



  touchscreen-size-x: true

  touchscreen-size-y: true
@@ -46,6 +53,7 @@ properties: 
  touchscreen-inverted-y: true

  touchscreen-swapped-x-y: true

  touchscreen-min-pressure: true

  touchscreen-x-plate-ohms: true



additionalProperties: false
@@ -68,3 +76,11 @@ examples: 
      io-channels = <&adc 24>, <&adc 25>, <&adc 26>;

      io-channel-names = "y", "pressure", "x";

    };

  - |

    touchscreen {

      compatible = "resistive-adc-touch";

      touchscreen-min-pressure = <50000>;

      io-channels = <&adc 1>, <&adc 2>, <&adc 3>, <&adc 4>;

      io-channel-names = "x", "z1", "z2", "y";

      touchscreen-x-plate-ohms = <800>;

    };