Input Listener: Auto Layer Toggle on mouse movement

[infused-kim]

This PR adds a way to toggle a layer whenever a mouse moves.

It was designed for the PS/2 Mouse & Trackpoint PR, but since it's using the new input listener system, it can be used with any mouse driver that's using the new zephyr 3.5 input system.

Configuration

In your shield.dtsi:

/ {
    mouse_ps2_input_listener: mouse_ps2_input_listener {
        compatible = "zmk,input-listener";
        status = "disabled";

        device = <&mouse_ps2>;
    };
};

As you can see the input config is disabled by default. Enable it only on the central half of your keyboard (such as shield_right.overlay:

&mouse_ps2_input_listener {
    status = "okay";
};

And then in your actual keymap:

&mouse_ps2_input_listener {
  xy-swap;
  x-invert;
  y-invert;

  // Set the layer that should automatically activate when the mouse is
  // moving.
  layer-toggle = <MOUSE_TP>;

  // How long the mouse needs to move for before the layer is activated (to
  // avoid accidental activations while typing) (Default: 250)
  layer-toggle-delay-ms = <250>;

  // How long to wait, after the last mouse movement, before deactivating
  // the layer (Default: 250)
  layer-toggle-timeout-ms = <250>;
};

[infused-kim]

I updated the code to the new input listener system and updated the PR description with the new config.

[Nick-Munnich]

This has been made obsolete by the input processors PR I believe.