linux-kernel - Re: input: mt: Software finger tracking in the kernel?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20100320194424.GC28402@core.coreip.homeip.net>
Date:	Sat, 20 Mar 2010 12:44:24 -0700
From:	Dmitry Torokhov <dmitry.torokhov@...il.com>
To:	Henrik Rydberg <rydberg@...esh.se>
Cc:	linux-input <linux-input@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: input: mt: Software finger tracking in the kernel?

Hi Henrik,

On Fri, Mar 19, 2010 at 11:58:35AM +0100, Henrik Rydberg wrote:
> Hi Dmitry,
> 
> there is an ongoing discussion about adding multitouch to X
> (http://lists.x.org/archives/xorg-devel/2010-March/006206.html), which is
> beginning to take on more solid form.
> 
> One of the suggestions emerging from that discussion is to add the software
> finger tracking to the kernel. Back in summer 2009 when I thought about this, I
> disregarded it as being too experimental. I have since then reconsidered,
> starting to think it really is the right place.
> 
> The MT protocol allows applications to take advantage of multi-contact hardware,
> but leaves the problems of finger tracking and filtering to the user. Arguably,
> no application can make good use of MT without these, so the problem is pushed
> forward, in this case to evdev or equivalent.
> 
> The knowledge of signal-to-noise ratios and prior input states resides in the
> kernel. Because of this, the finger matching and filtering would naturally
> reside within the kernel.
> 
> So, if there were to appear patches to include matching in the input core, would
> you consider them? :-)
> 

I am not sure if input core itself is the proper place to do such
thing, I'd envisioned something more like a library providing common
code that drivers could opt in to use, like we hane ff-memless for
memory-less force-feedback devices.

Does it make any sense? I guess post the skeleton of the code and we can
discuss further.

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