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From: Jiri Kosina <jikos@jikos.cz>
To: Oliver Neukum <oliver@neukum.org>
Cc: linux-input@atrey.karlin.mff.cuni.cz,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	linux-usb-devel@lists.sourceforge.net
Subject: Re: detecting when keys are being pressed on a keyboard
Date: Mon, 24 Sep 2007 15:45:59 +0200 (CEST)	[thread overview]
Message-ID: <Pine.LNX.4.64.0709241544540.22331@twin.jikos.cz> (raw)
In-Reply-To: <200709241256.05300.oliver@neukum.org>

On Mon, 24 Sep 2007, Oliver Neukum wrote:

> > HID doesn't keep any permanent state by itself. If you want to know 
> > whether a given key is currently pressed or not, you'd have to inspect 
> > the bitfields inside input_dev*, I am afraid.
> I see no way to do this without a race condition. The field isn't locked
> as far as I can tell.

Hi Oliver,

Dmitry (CC added) has been doing a lot of rework of locking in input as 
far as I know. He would know this better.

> Secondly, what is to happen in case of a system wide suspend? Will
> the system wake up thinking that the key is still pressed?

If the release event didn't happen before the machine went to suspend, I'd 
say so.

-- 
Jiri Kosina

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      parent reply	other threads:[~2007-09-24 13:45 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-09-21  8:33 detecting when keys are being pressed on a keyboard Oliver Neukum
2007-09-21 12:47 ` Jiri Kosina
2007-09-24 10:56   ` Oliver Neukum
2007-09-24 12:50     ` [linux-usb-devel] " Dmitry Torokhov
2007-09-24 13:39       ` Oliver Neukum
2007-09-24 13:45         ` Dmitry Torokhov
2007-09-24 13:54           ` Oliver Neukum
2007-09-24 13:45     ` Jiri Kosina [this message]

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