Re: Input issues - key down with no key up

From: Andries Brouwer
Date: Fri Aug 15 2003 - 07:41:08 EST


On Fri, Aug 15, 2003 at 12:58:02PM +0200, Vojtech Pavlik wrote:

> > > I have a notebook (Dell Latitude D800) which has some keys (actual
> > > fn+something combinations) that generate Down events but no Up events
> > > (clever, isn't it).
> > > This makes those keys unusable with 2.6.0 as it is

> > I think we should go for the simple fix: only enable the timer-induced
> > repeat when the user asks for that (say, by boot parameter).
> > The keyboard already knows which keys repeat and which don't.

> That won't solve it - the key, while not repeating would be still
> considered 'down' by the kernel and any more pressing of the key
> wouldn't do anything.

Yes, it would still be considered down. But that does not imply
that pressing it doesnt do anything. It is up to the driver
to discard key presses, and I think it shouldnt.
(Unless of course the user asks for that behaviour - it may be required
on some broken laptops.)

Just the simple: a keypress generates an interrupt and we see a keystroke.

Use a kernel timer only when we know or the user tells us that it is needed.
Not in the default situation.

> My proposed solution is to do an input_report_key(pressed) immediately
> followed by input_report_key(released) for these keys straight in
> atkbd.c. Possibly based on some flag in the scancode->keycode table for
> that scancode.

But that would require users to report on precisely which keys are affected
and would give complications where I suppose 2.4 did not have any.
This is the way towards an ever more complicated keyboard driver.
Not what you would want.

Andries

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