Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation

Pavel Machek
2017-02-18T22:57:31Z

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On Sat 2017-02-18 20:17:09, H. Nikolaus Schaller wrote:
>
> > Am 18.02.2017 um 19:08 schrieb Pavel Machek <pavel@ucw.cz>:
> >
> >>> And I agree that kernel should _not_ attempt rescaling itself, as it
> >>> would lose precision.
> >>
> >> With an almost 1:1 mapping you won't loose precision.
> >
> > How do you propose to do that?
>
> something like
>
> xinput --set-prop --type=float "TSC200X touchscreen" "Coordinate Transformation Matrix" 1.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 1.00
>
> but I think it is the default of X11 if you use no coordinate transformation at all.
> And having the kernel to properly scale from ADC values to screen coordinates.
>

No. How do you propose doing rescaling in the kernel without loosing
precision?
Pavel
--
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