From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261852AbVBIROr (ORCPT ); Wed, 9 Feb 2005 12:14:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261853AbVBIROq (ORCPT ); Wed, 9 Feb 2005 12:14:46 -0500 Received: from lug-owl.de ([195.71.106.12]:17844 "EHLO lug-owl.de") by vger.kernel.org with ESMTP id S261852AbVBIROj (ORCPT ); Wed, 9 Feb 2005 12:14:39 -0500 Date: Wed, 9 Feb 2005 18:14:38 +0100 From: Jan-Benedict Glaw To: LKML , Linux-Input Cc: Paulo Marques , Vojtech Pavlik Subject: Re: [RFC/RFT] [patch] Elo serial touchscreen driver Message-ID: <20050209171438.GI10594@lug-owl.de> Mail-Followup-To: LKML , Linux-Input , Paulo Marques , Vojtech Pavlik References: <20050208164227.GA9790@ucw.cz> <420A0ECF.3090406@grupopie.com> <20050209170015.GC16670@ucw.cz> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="2MeieX8lS1K8IJ9W" Content-Disposition: inline In-Reply-To: <20050209170015.GC16670@ucw.cz> X-Operating-System: Linux mail 2.6.10-rc2-bk5lug-owl X-gpg-fingerprint: 250D 3BCF 7127 0D8C A444 A961 1DBD 5E75 8399 E1BB X-gpg-key: wwwkeys.de.pgp.net User-Agent: Mutt/1.5.6+20040907i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --2MeieX8lS1K8IJ9W Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, 2005-02-09 18:00:15 +0100, Vojtech Pavlik wrote in message <20050209170015.GC16670@ucw.cz>: > On Wed, Feb 09, 2005 at 01:23:27PM +0000, Paulo Marques wrote: > > Vojtech Pavlik wrote: > > >Hi! > > > > > >I've written a driver for probably the most common touchscreen type - > > >the serial Elo touchscreen. > >=20 > > If we are serious about getting support for serial touchscreens into th= e=20 > > kernel, I can certainly give a hand there. >=20 > I want serious support for ALL touchscreens in Linux. Maybe I'd write drivers for the T-Sharc and fujitsu controllers, too. These are in a lot of POS hardware, too, and sometimes they're a pain to use (esp. calibration). Linux at the Point Of Sale is quite well running (I'm employed at a POS software company). > And I'm glad there is interest. :) If I find a minute, I'll possibly give it a test run. I've got actual hardware around. > > Also, I've already seen touchscreens where the POS manufacturer got the= =20 > > pin-out wrong (or something like that) so the touch reports the X=20 > > coordinate where the Y should be, and vice-versa. I really don't know= =20 > > where this should be handled (driver, input layer, application?), but i= t=20 > > must be handled somewhere for the applications to work. >=20 > I think the best place would be in the X event driver, if X is used, or > the graphics toolkit, and worst case the application. First of all, we need a really properly working Linux event driver in XFree86/X.Org. I'm not sure if this is already the case. > I don't believe the mirroring/flipping is kernel's job, since it tries > to always pass the data with the least amount of transformation applied > to achieve hardware abstraction. ACK. Should be handled by XFree86's driver. Additionally, there are two other things that need to be addressed (and I'm willing to actually write code for this, but need input from other parties, too:) - Touchscreen calibration Basically all these touchscreens are capable of being calibrated. It's not done with just pushing the X/Y values the kernel receives into the Input API. These beasts may get physically mis-calibrated and eg. report things like (xmax - xmin) <=3D 20, so resolution would be really bad and kernel reported min/max values were only "theoretical" values, based on the protocol specs. I think about a simple X11 program for this. Comments? - POS keyboards These are real beasties. Next to LEDs and keycaps, they can contain barcode scanners, magnetic card readers and displays. Right now, there's no good API to pass something as complex as "three-track magnetic stripe data" or a whole scanned EAN barcode. Also, some keyboards can be written to (change display contents, switch on/off scanners, ...). This is usually "solved" with a little patch that allows userspace to write to the keyboard (/dev/psaux like), but this is a bad hack (just look at the patches floating around for this...). MfG, JBG --=20 Jan-Benedict Glaw jbglaw@lug-owl.de . +49-172-7608481 = _ O _ "Eine Freie Meinung in einem Freien Kopf | Gegen Zensur | Gegen Krieg = _ _ O fuer einen Freien Staat voll Freier B=C3=BCrger" | im Internet! | im Ira= k! O O O ret =3D do_actions((curr | FREE_SPEECH) & ~(NEW_COPYRIGHT_LAW | DRM | TCPA)= ); --2MeieX8lS1K8IJ9W Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.5 (GNU/Linux) iD8DBQFCCkT+Hb1edYOZ4bsRAvuGAJ9YMGrVsCH1uKKqBgEw+VSbtCwi9gCfb9cd rgEULRfGKS0kiJDKQbyRBlM= =BXGu -----END PGP SIGNATURE----- --2MeieX8lS1K8IJ9W--