Am Mittwoch, den 19.06.2019, 07:46 -0600 schrieb Rob Herring:
> On Wed, Jun 19, 2019 at 6:47 AM Middelschulte, Leif
> <
> Leif.Middelschulte@xxxxxxxxxxxxx
> > wrote:
> > Am Freitag, den 14.06.2019, 13:58 -0600 schrieb Rob Herring:
> > > On Mon, May 27, 2019 at 06:19:37PM +0200, Leif Middelschulte wrote:
> > > > The tracking index is a "minimum" distance two touch
> > > > points need to have in order for the second to be valid.
> > > > This adds the corresponding binding property documentation.
> > > >
> > > > Signed-off-by: Leif Middelschulte <
> > > > leif.middelschulte@xxxxxxxxxxxxx
> > > >
> > > >
> > > > ---
> > > > .../bindings/input/touchscreen/stmpe.txt | 15 +++++++++++++++
> > > > 1 file changed, 15 insertions(+)
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt b/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt
> > > > index 09d2d4f288cc..8696af35a7b8 100644
> > > > --- a/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt
> > > > +++ b/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt
> > > > @@ -42,6 +42,21 @@ Optional properties:
> > > > The given window also affects the value range (limits) set
> > > > within the input subsystem which, in turn, affects
> > > > the input resolution calculation on both axes.
> > > > +- st,tracking-index : Minimal distance between the current touch position and the previous
> > > > + touch position. If the distance is shorter than the tracking
> > > > + index, it is discarded. The tracking is calculated by summation
> > > > + of the horizontal and vertical movement.
> > > > + If pressure reporting is enabled (X/Y/Z), an increase in pressure
> > > > + override the movement tracking and report the new data set, even
> > > > + if X/Y is within the previous tracking index.
> > > > + 0 -> disabled
> > > > + 1 -> 4
> > > > + 4 -> 8
> > > > + 3 -> 16
> > > > + 4 -> 32
> > > > + 5 -> 64
> > > > + 6 -> 92
> > > > + 7 -> 127
> > >
> > > This is what touchscreen-fuzz-x/y is for.
> >
> > The stmpe touchcontroller does not support handling each axis separately.
> > Also it is not to be mistaken in its specific behavior (i.e. override)
> > for the general `fuzz` parameter. However, should I rename it to `st,fuzz-x-y` or similar?
> >
> > AFAICS there[0] is no generic combined devicetree property, is there?
>
> Can't you set both properties and require them to be the same value?
The documentation would have to mention the (deviating) behavior possibly like follows:
``` This snippet is adapted from eeti.txt[0]
The following optional properties described in touchscreen.txt are
also supported:
- touchscreen-fuzz-x: This value needs to be the same as touchscreen-fuzz-y.
It is futhermore ignored, if the Z-axis is acquired too and an increase in pressure is detected.
The given value is a sum of the distances of both axis.
- touchscreen-fuzz-y: This value needs to be the same as touchscreen-fuzz-x.
It is futhermore ignored, if the Z-axis is acquired too and an increase in pressure is detected.
The given value is a sum of the distances of both axis.
```
Seems a bit odd to imagine. How would you suggest to it to look like?
It seems, to me, that either a general combined value should be introduced or this should be left stmpe specific (especially when considering the override behavior).
[0] https://www.kernel.org/doc/Documentation/devicetree/bindings/input/touchscreen/eeti.txt
Leif
>
> Rob
>
