From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rafi Rubin Subject: Re: [PATCH] hid-ntrig.c Multitouch cleanup and fix Date: Tue, 09 Mar 2010 17:12:59 -0500 Message-ID: <4B96C7EB.2000801@seas.upenn.edu> References: <4B75E14A.2050602@seas.upenn.edu> <1266027185-5311-1-git-send-email-rafi@seas.upenn.edu> <4B760D60.6020907@seas.upenn.edu> <4B96B740.7020208@euromail.se> <4B96BAF1.5070209@seas.upenn.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from stag.seas.upenn.edu ([158.130.70.79]:46366 "EHLO stag.seas.upenn.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755397Ab0CIWNL (ORCPT ); Tue, 9 Mar 2010 17:13:11 -0500 In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Jiri Kosina Cc: Henrik Rydberg , linux-input@vger.kernel.org, dmitry.torokhov@gmail.com, chatty@enac.fr On 03/09/2010 04:19 PM, Jiri Kosina wrote: > On Tue, 9 Mar 2010, Rafi Rubin wrote: > >> Since you're considering protocol clarification, what's your opinion on >> splitting the multi-touch and single touch (possibly emulated) to >> separate input devices? > > What would be the advantages? With the N-Trig device it would more closely match the device rdesc. At least for the firmwares I've had a chance to examine. hid device describes 3 input devices: 1. pen, 2. multi touch, 3. single touch. Depending on the mode, the hardware sends single touch events to either the mt report (mt modes) or single touch report. If mt/st multiplexing is preferred, perhaps it would be better to adjust the device naming, and possibly collapse the second and third devices into a single device. Either way, I think it would be more aesthetically pleasing to keep the behavior of the input devices as consistent as possible and not having events jump from dev to dev based on the direction of the wind. The only real reason I see to argue in favor of splitting the two streams is as a crutch to inadequate user space tools. So perhaps that's not even worth discussing. So how can I prevent the third input from being allocated without eliminating the second? Rafi