Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759399Ab2EJMPd (ORCPT ); Thu, 10 May 2012 08:15:33 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:45014 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756492Ab2EJMPc (ORCPT ); Thu, 10 May 2012 08:15:32 -0400 MIME-Version: 1.0 In-Reply-To: <20120509194623.GA12381@polaris.bitmath.org> References: <1336136030-18503-1-git-send-email-benjamin.tissoires@gmail.com> <1336136030-18503-3-git-send-email-benjamin.tissoires@gmail.com> <20120506190322.GB12571@polaris.bitmath.org> <20120509194623.GA12381@polaris.bitmath.org> Date: Thu, 10 May 2012 14:15:31 +0200 Message-ID: Subject: Re: [PATCH 2/5] HID: hid-multitouch: get maxcontacts also from logical_max value From: Benjamin Tissoires To: Henrik Rydberg Cc: Dmitry Torokhov , Jiri Kosina , Stephane Chatty , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1879 Lines: 45 On Wed, May 9, 2012 at 9:46 PM, Henrik Rydberg wrote: > Hi Benjamin, > >> >> Win8 devices are required to present the feature "Maximum Contact Number". >> >> If the current value is 0, then, the driver can get the actual supported >> >> contact count by seeing the logical_max. >> > >> > And for win7, it is zero? >> >> Well, the truth is that the Win8 specification formally describes the >> values here. And to get the certification, hardware makers have to put >> the right value in logical_max. >> TBH, I don't care that much now with win7 devices. Most of them are a >> piece of crap (not true dual fingers, problems in hid reports >> descriptors, etc...), but they just work (we made the necessary >> things). With the introduction of Win8, hardware makers will have to >> *certify* their devices, and thus, the Win8 driver is much less >> tolerant. I really think that we are going to see more and more win8 >> devices, whereas win7 devices will fade out. >> >> I had to add this patch because I have a win8 device that has the >> value associated to this field at 0, and it's the first I saw with >> this behavior. > > As long as all existing devices are unaffected, it's fine, hence the question. I checked all the reports descriptors that I have. 2 devices (one Stantum and one Irtouch) present an unrealistic logical_max value (255). The thing is that if this logical_max is false, and if the value is not provided, then I don't know how could I retrieve the right value beside introducing a MT_CLS... Henrik, do you think that 255 is two much for the slots? Thanks, Benjamin > > Thanks, > Henrik -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/