Hi Javier, This is excellent, just one small comment below. On Wed, Dec 20, 2023 at 09:39:43AM +0100, Javier Carrasco wrote: > The touch-overlay encompasses a number of touch areas that define a > clipped touchscreen area and/or buttons with a specific functionality. > > A clipped touchscreen area avoids getting events from regions that are > physically hidden by overlay frames. > > For touchscreens with printed overlay buttons, sub-nodes with a suitable > key code can be defined to report key events instead of the original > touch events. > > Signed-off-by: Javier Carrasco <javier.carrasco@xxxxxxxxxxxxxx> > --- > .../bindings/input/touchscreen/touchscreen.yaml | 119 +++++++++++++++++++++ > 1 file changed, 119 insertions(+) > > diff --git a/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml b/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml > index 431c13335c40..d5ac90667bef 100644 > --- a/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml > +++ b/Documentation/devicetree/bindings/input/touchscreen/touchscreen.yaml > @@ -87,6 +87,125 @@ properties: > touchscreen-y-plate-ohms: > description: Resistance of the Y-plate in Ohms > > + touch-overlay: > + description: list of nodes defining segments (touch areas) on the > + touchscreen. > + > + This object can be used to describe a series of segments to > + restrict the region within touch events are reported or buttons > + with a specific functionality. > + > + This is of special interest if the touchscreen is shipped with a physical > + overlay on top of it with a frame that hides some part of the original > + touchscreen area. Printed buttons on that overlay are also a typical > + use case. > + > + A new touchscreen area is defined as a sub-node without a key code. If a > + key code is defined in the sub-node, it will be interpreted as a button. > + > + The x-origin and y-origin properties of a touchscreen area define the > + offset of a new origin from where the touchscreen events are referenced. > + This offset is applied to the events accordingly. The x-size and y-size > + properties define the size of the touchscreen effective area. > + > + The following example shows a new touchscreen area with the new origin > + (0',0') for the touch events generated by the device. > + > + Touchscreen (full area) > + ┌────────────────────────────────────────┐ > + │ ┌───────────────────────────────┐ │ > + │ │ │ │ > + │ ├ y-size │ │ > + │ │ │ │ > + │ │ touchscreen area │ │ > + │ │ (no key code) │ │ > + │ │ │ │ > + │ │ x-size │ │ > + │ ┌└──────────────┴────────────────┘ │ > + │(0',0') │ > + ┌└────────────────────────────────────────┘ > + (0,0) > + > + where (0',0') = (0+x-origin,0+y-origin) > + > + Sub-nodes with key codes report the touch events on their surface as key > + events instead. > + > + The following example shows a touchscreen with a single button on it. > + > + Touchscreen (full area) > + ┌───────────────────────────────────┐ > + │ │ > + │ │ > + │ ┌─────────┐ │ > + │ │button 0 │ │ > + │ │KEY_POWER│ │ > + │ └─────────┘ │ > + │ │ > + │ │ > + ┌└───────────────────────────────────┘ > + (0,0) > + > + Segments defining buttons and clipped toushcreen areas can be combined > + as shown in the following example. > + In that case only the events within the touchscreen area are reported > + as touch events. Events within the button areas report their associated > + key code. Any events outside the defined areas are ignored. > + > + Touchscreen (full area) > + ┌─────────┬──────────────────────────────┐ > + │ │ │ > + │ │ ┌───────────────────────┐ │ > + │ button 0│ │ │ │ > + │KEY_POWER│ │ │ │ > + │ │ │ │ │ > + ├─────────┤ │ touchscreen area │ │ > + │ │ │ (no key code) │ │ > + │ │ │ │ │ > + │ button 1│ │ │ │ > + │ KEY_INFO│ ┌└───────────────────────┘ │ > + │ │(0',0') │ > + ┌└─────────┴──────────────────────────────┘ > + (0,0) > + > + type: object > + > + patternProperties: > + '^segment-': > + type: object > + description: > + Each segment is represented as a sub-node. > + properties: > + x-origin: > + description: horizontal origin of the node area > + $ref: /schemas/types.yaml#/definitions/uint32 > + > + y-origin: > + description: vertical origin of the node area > + $ref: /schemas/types.yaml#/definitions/uint32 > + > + x-size: > + description: horizontal resolution of the node area > + $ref: /schemas/types.yaml#/definitions/uint32 > + > + y-size: > + description: vertical resolution of the node area > + $ref: /schemas/types.yaml#/definitions/uint32 > + > + label: > + $ref: /schemas/types.yaml#/definitions/string > + description: descriptive name of the button Please consider replacing the word "button" with "segment"; as we see in patch [3/4], the label can describe a touch surface and not just a button. > + > + linux,code: true > + > + required: > + - x-origin > + - y-origin > + - x-size > + - y-size > + > + unevaluatedProperties: false > + > dependencies: > touchscreen-size-x: [ touchscreen-size-y ] > touchscreen-size-y: [ touchscreen-size-x ] > > -- > 2.39.2 > > With that changed, feel free to add: Reviewed-by: Jeff LaBundy <jeff@xxxxxxxxxxx> Obviously we need Dmitry and the binding maintainers to review as well; I am merely expressing my own agreement as a future customer of this function. Kind regards, Jeff LaBundy
