Re: Keys get stuck

From: Pavel Machek
Date: Thu Mar 13 2008 - 13:15:40 EST


On Wed 2008-03-12 21:14:56, David Newall wrote:
> Jiri Kosina wrote:
> > Very probably this is due to broken way how X themselves implement
> > auto-repeat, instead of using kernel-provided auto-repeat functionality.
>
> It should be said that X implements auto-repeat out of necessity. While
> the kernel can report key down and up events, its further interpretation
> of those events is not appropriate. Many combinations of events are
> possible, such as keyboard plus mouse, and this precludes the kernel
> from providing a full interpretation. It would be wrong for it to even
> try. X is the proper place to implement auto-repeat for X.

No.

hw is proper place to implement autorepeat, and along with some
buffering, it has chance to work. Kernel is not real-time, and X are
definitely not real-time, while autorepeat is real-time operation.

It actually mostly works in ps/2 case. Buffer in hardware means that
pretty big interrupt delays can be tolerated without problems.

--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
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/