Re: [RFC v1 0/4] Input: support virtual objects on touchscreens

[Michael Riesch]

Hi Pavel,

On 4/27/23 13:04, Pavel Machek wrote:
> Hi!
> 
>> Some touchscreens are shipped with a physical layer on top of them where
>> a number of buttons and a resized touchscreen surface might be
>> available.
> 
> Yes, it is quite comon, for example Motorola Droid 4 has 4 virtual
> buttons below touchscreen.

Are those buttons configurable in some way? Or do they have a fixed purpose?

How does Android handle those buttons, BTW?

> One question is if this should be handled inside the kernel. It will
> make it compatible with existing software, but it will also reduce
> flexibility.

I would say that it should be described in device tree if the purpose is
fixed. For example, if there is no display behind the touch screen at a
certain point but a printed sheet (e.g., with a home or return symbol)
then it is clear that this button is not going to change. In such a case
I doubt that flexibility is required.

Best regards, Michael

> 
> Best regards,
> 								Pavel