From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sadrul Chowdhury Subject: Re: [PATCH] input-mt: Allow -1 for tracking id Date: Fri, 15 Apr 2011 09:09:58 -0400 Message-ID: References: <20110415070000.GA7135@polaris.bitmath.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: Received: from smtp-out.google.com ([216.239.44.51]:9479 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754138Ab1DONKV (ORCPT ); Fri, 15 Apr 2011 09:10:21 -0400 Received: from kpbe12.cbf.corp.google.com (kpbe12.cbf.corp.google.com [172.25.105.76]) by smtp-out.google.com with ESMTP id p3FDAJPY028940 for ; Fri, 15 Apr 2011 06:10:19 -0700 Received: from iye19 (iye19.prod.google.com [10.241.50.19]) by kpbe12.cbf.corp.google.com with ESMTP id p3FDAIt1028181 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Fri, 15 Apr 2011 06:10:18 -0700 Received: by iye19 with SMTP id 19so2901465iye.31 for ; Fri, 15 Apr 2011 06:10:18 -0700 (PDT) In-Reply-To: <20110415070000.GA7135@polaris.bitmath.org> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Henrik Rydberg Cc: linux-input@vger.kernel.org On Fri, Apr 15, 2011 at 3:00 AM, Henrik Rydberg wrote: > Hi Sadrul, > > On Thu, Apr 14, 2011 at 06:13:17PM -0400, Sadrul Chowdhury wrote: >> In protocol B, the tracking ID can be set to -1. But since the min >> value is set to 0, the clients don't receive a -1 when a contact is >> lifted. The attached patch sets the min to -1 to fix this issue. > > All ABS_MT_TRACKING_ID values outside the valid value range denote an > invalid touch. To simplify implementation in userland, where the valid > range may not always be known, the documentation was changed to say > "-1" instead. Apparently the original explanation was unintentionally > dropped with it. > > Because the change goes against the semantics of the tracking id, this > patch constitues an interface breakage, with malfunctions in userspace > as a result. Therefore, this patch will not be applied. Ah, that makes sense. Thanks for the explanation. I will fix things on the client end. Thanks. Sadrul