From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH 2/2] Support for Stantum multitouch panel Date: Thu, 10 Dec 2009 16:47:20 -0800 Message-ID: <20091211004719.GG23717@core.coreip.homeip.net> References: <20091209214928.1E24D9520C@smtp.lii-enac.fr> <20091209231516.GF10138@core.coreip.homeip.net> <25E41E82-8D85-43DB-A47C-4F7FBDA0293F@enac.fr> <20091210182844.GC23717@core.coreip.homeip.net> <20091211000318.GE13607@barra.bne.redhat.com> <20091211001922.GF23717@core.coreip.homeip.net> <20091211003504.GF13607@barra.bne.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pz0-f188.google.com ([209.85.222.188]:38333 "EHLO mail-pz0-f188.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762094AbZLKArU (ORCPT ); Thu, 10 Dec 2009 19:47:20 -0500 Received: by pzk26 with SMTP id 26so284958pzk.4 for ; Thu, 10 Dec 2009 16:47:26 -0800 (PST) Content-Disposition: inline In-Reply-To: <20091211003504.GF13607@barra.bne.redhat.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Peter Hutterer Cc: =?iso-8859-1?Q?St=E9phane?= Chatty , linux-input@vger.kernel.org, Rafi Rubin , Benjamin Tissoires On Fri, Dec 11, 2009 at 10:35:04AM +1000, Peter Hutterer wrote: > On Thu, Dec 10, 2009 at 04:19:22PM -0800, Dmitry Torokhov wrote: > > > are we talking about kernel drivers or userspace drivers here? > > > > > > not handling ABS_MT_X, ABS_MT_Y properly in evdev is a bug (well, > > > not-yet-implemented feature) but if the kernel hands out both ABS_X and > > > ABS_MT_X that makes it difficult to determine which event is a valid one and > > > which one can be ignored. > > > > > > > No, it is pretty simple - all events are valid, otherwise it is kernel > > driver bug. Now, as userspace consumer, if you know how to handle > > multitouch protocol then use it, ignore ABS_X/ABS_Y. Otherwise you'd be > > dropping ABS_MT_* events and naturally handling ABS_X/ABS_Y. > > Thanks, that's the answer I hoped for - if ABS_MT_X is available, we can > ignore ABS_X. > > The tricky part would have been if both were equally valid _at the same > time_ but refer to different inputs. at which point you'd have to find out > which one to map to which pointer axis, etc. We already have a problem with > REL_X and ABS_X on the same device, adding the ABS_MT_X to that mess > wouldn't have helped the situation. What devices report both ABS_X and REL_X events? -- Dmitry