Re: [PATCH 2/2] input: mt: Document the MT event slot protocol (rev2)

From: Dmitry Torokhov
Date: Mon May 24 2010 - 14:04:23 EST


On Mon, May 24, 2010 at 07:48:00PM +0200, Henrik Rydberg wrote:
> Dmitry Torokhov wrote:
> [...]
> >>>> I think we need to add an ioctl to enable user land driver/client to
> >>>> signal the kernel driver to send all events without filtering, just
> >>>> once. Hot-plugged devices and X driver starts after user has contacted
> >>>> with the device are two examples that the client would miss filtered
> >>>> events.
> >>>>
> >>>> Dmitry, do you think it is a valid suggestion?
> >>> What about using EVIOCGKEY/EVIOCGSW/EVIOCGABS?
> >> Those EVIOCs only give us the static values (max/min/supported keys,
> >> etc.). We need their dynamic input data here, the actual x, y,
> >> button, pressure, etc. Am I missing something about those EVIOs?
> >>
> >
> > Yes you are ;) Supported events are reported via EVIOCGBIT, EVIOCGKEY and
> > EVIOCGSW will return current state of keys/switches. As far as EVIOCGABS
> > goes, it also returns, besides min/max/etc, last reported _values_ of the
> > ABS_* events.
> >
>
> Ping is not alone. :-)
>
> But it does not work for MT events -- yet.
>

Yes, this is true.

I think the most interesting is the switch data, since they may not change
at all. The rest is transient and should refresh "fairly quickly".

--
Dmitry
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/