Re: [PATCH] new driver for ITM Touch touchscreen

From: Dmitry Torokhov
Date: Tue Mar 08 2005 - 12:26:56 EST


On Tue, 08 Mar 2005 17:01:00 +0100, Hans-Christian Egtvedt <hc@xxxxxxx> wrote:
> On Fri, 2005-03-04 at 11:54 -0500, Dmitry Torokhov wrote:
> > On Fri, 04 Mar 2005 17:20:24 +0100, Hans-Christian Egtvedt <hc@xxxxxxx> wrote:
> > > On Fri, 2005-03-04 at 09:52 -0500, Dmitry Torokhov wrote:
> > > > On Fri, 4 Mar 2005 14:03:37 +0200, Alexey Dobriyan <adobriyan@xxxxxxx> wrote:
> > > > > On Friday 04 March 2005 12:30, Hans-Christian Egtvedt wrote:
> > > > As far as the driver goes:
> > > >
> > > > - yes, it does need input_sync;
> > >
> > > One problem with input_sync is that the panel get's too fast, and double
> > > click is experienced quite often, maybe some threshold is needed for low
> > > values in Z-direction?
> > >
> > > I'm probably doing something wrong here since I experience easy
> > > doubleclicks when I just lightly touch the screen.
> >
> > Yes, I think you need to use some threshold when reporting BTN_TOUCH
> > event. Still, always report ABS_PRESSURE as is. This way the
> > touchscreen is useable via legacy interfaces (mousedev. tsdev) and if
> > a specialized userspace driver is written it still can get pretty much
> > unmangled data from /dev/input/eventX. This will also allow such
> > driver adjust touchpad sensitivity, if needed.
>
> Do you have any pointers to where I should go to implement this
> threshold? Is there an easy or smart way doing it?
>

I am not sure... that BTN_TOUCH - look slike it works off a single
flag reported by hardware. You porobably do not need to change it.

Try loading mousedev module (after adding input_sync back to your
driver) - it provides cooked PS/2 protocol to userspace - it should
bind to your driver. Then you can use GPM or X (read from
/dev/input/mice) to test the touchscreen and see if you have issue
with double clicks.

--
Dmitry
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