Re: [PATCH v3 1/3] dt-bindings: input: atmel_mxt_ts: Document atmel,wakeup-method and wake-GPIO

[Rob Herring <robh@kernel.org>]

On Mon, Dec 07, 2020 at 12:22:15AM +0300, Dmitry Osipenko wrote:
> Some Atmel touchscreen controllers have a WAKE line that needs to be
> asserted low in order to wake up controller from a deep sleep. Document
> the wakeup methods and the wake-GPIO properties.

wake-GPIO?

> 
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
>  .../bindings/input/atmel,maxtouch.yaml        | 29 +++++++++++++++++++
>  include/dt-bindings/input/atmel-maxtouch.h    | 10 +++++++
>  2 files changed, 39 insertions(+)
>  create mode 100644 include/dt-bindings/input/atmel-maxtouch.h
> 
> diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.yaml b/Documentation/devicetree/bindings/input/atmel,maxtouch.yaml
> index 8c6418f76e94..e6b03a1e7c30 100644
> --- a/Documentation/devicetree/bindings/input/atmel,maxtouch.yaml
> +++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.yaml
> @@ -39,6 +39,13 @@ properties:
>        (active low). The line must be flagged with
>        GPIO_ACTIVE_LOW.
>  
> +  wake-gpios:
> +    maxItems: 1
> +    description:
> +      Optional GPIO specifier for the touchscreen's wake pin
> +      (active low). The line must be flagged with
> +      GPIO_ACTIVE_LOW.
> +
>    linux,gpio-keymap:
>      $ref: /schemas/types.yaml#/definitions/uint32-array
>      description: |
> @@ -53,6 +60,26 @@ properties:
>        or experiment to determine which bit corresponds to which input. Use
>        KEY_RESERVED for unused padding values.
>  
> +  atmel,wakeup-method:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: |
> +      The WAKE line is an active-low input that is used to wake up the touch
> +      controller from deep-sleep mode before communication with the controller
> +      could be started. This optional feature used to minimize current
> +      consumption when the controller is in deep sleep mode. This feature is
> +      relevant only to some controller families, like mXT1386 controller for
> +      example.
> +
> +      The WAKE pin can be connected in one of the following ways:
> +       1) left permanently low
> +       2) connected to the I2C-compatible SCL pin
> +       3) connected to a GPIO pin on the host
> +    enum:
> +      - 0 # ATMEL_MXT_WAKEUP_NONE
> +      - 1 # ATMEL_MXT_WAKEUP_I2C_SCL
> +      - 2 # ATMEL_MXT_WAKEUP_GPIO
> +    default: 0
> +
>  required:
>    - compatible
>    - reg
> @@ -63,6 +90,7 @@ additionalProperties: false
>  examples:
>    - |
>      #include <dt-bindings/interrupt-controller/irq.h>
> +    #include <dt-bindings/input/atmel-maxtouch.h>
>      #include <dt-bindings/gpio/gpio.h>
>      i2c {
>        #address-cells = <1>;
> @@ -75,6 +103,7 @@ examples:
>          reset-gpios = <&gpio 27 GPIO_ACTIVE_LOW>;
>          vdda-supply = <&ab8500_ldo_aux2_reg>;
>          vdd-supply = <&ab8500_ldo_aux5_reg>;
> +        atmel,wakeup-method = <ATMEL_MXT_WAKEUP_I2C_SCL>;
>        };
>      };
>  
> diff --git a/include/dt-bindings/input/atmel-maxtouch.h b/include/dt-bindings/input/atmel-maxtouch.h
> new file mode 100644
> index 000000000000..7345ab32224d
> --- /dev/null
> +++ b/include/dt-bindings/input/atmel-maxtouch.h
> @@ -0,0 +1,10 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +
> +#ifndef _DT_BINDINGS_ATMEL_MAXTOUCH_H
> +#define _DT_BINDINGS_ATMEL_MAXTOUCH_H
> +
> +#define ATMEL_MXT_WAKEUP_NONE		0
> +#define ATMEL_MXT_WAKEUP_I2C_SCL	1
> +#define ATMEL_MXT_WAKEUP_GPIO		2
> +
> +#endif /* _DT_BINDINGS_ATMEL_MAXTOUCH_H */
> -- 
> 2.29.2
>