Re: [PATCH 0/6] Add touch-keys support to the Zinitix touch driver

[Linus Walleij <linus.walleij@linaro.org>]

On Tue, Nov 9, 2021 at 4:23 PM Nikita Travkin <nikita@trvn.ru> wrote:
> [Me]
> > Have you notices some behaviour like surplus touch events
> > (like many press/release events fall through to the UI)
> > when using this driver? I think it might need some z fuzzing
> > but I am not sure.
> >
>
> On my device (8 inch tablet with BT532) I saw no problems with touch
> so far. However another person with a different tablet (10 inch with
> ZT7554)
> indeed says that they notice "multiplied" touches that make typing hard
> so maybe that depends on controller model/firmware...

It may even be depending on specimen. I saw that the vendor driver
does contain some debouncing code.

> And speaking of that ZT7554: Seems like it's works with the driver
> and I'd like to add the compatible for it in v2 but I'd also have to add
> it to the bindings. Looking at how you add all other similar names for BT*
> there does it make sense to add ZT* as well?

Yeah probably, if they are electrically very similar.

> Maybe you have some hints where
> to look for a list of the models?

I usually google ... try to find things like powerpoints with roadmaps
from the vendor and things like that. Best thing is if they answer
to mail but I don't know if Zinitix are even around anymore.

> I've noticed a yet another quirky issue with the touch controller:
> At least on my device, for some reason enabling touchkeys changes the
> way the
> controller reports the finger touch events which breaks multi-touch...
> Assuming that *not* enabling the touchkeys leads to calibration being
> wrong
> (controller assigns the touchkey sense lines to the touch area in that
> case)
> I now have to resolve this quirk as well...

Hm yeah I guess refer to the (messy) vendor driver for hints.

Yours,
Linus Walleij