From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chase Douglas Subject: Re: [PATCH] HID: magicmouse: Implement Multi-touch Protocol B (MT-B) Date: Mon, 02 Jul 2012 11:50:52 -0700 Message-ID: <4FF1ED8C.2080805@canonical.com> References: <1340913271-588-1-git-send-email-miletus@chromium.org> <20120702100741.GA1496@polaris.bitmath.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from youngberry.canonical.com ([91.189.89.112]:47948 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752520Ab2GBSu6 (ORCPT ); Mon, 2 Jul 2012 14:50:58 -0400 In-Reply-To: <20120702100741.GA1496@polaris.bitmath.org> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Henrik Rydberg Cc: Yufeng Shen , linux-input@vger.kernel.org, Jiri Kosina , linux-kernel@vger.kernel.org, Daniel Kurtz , Andrew de los Reyes On 07/02/2012 03:07 AM, Henrik Rydberg wrote: > On Thu, Jun 28, 2012 at 03:54:31PM -0400, Yufeng Shen wrote: >> The driver for Apple Magic Trackpad/Mouse currently uses >> Multi-touch Protocol A (MT-A) to report touch events and uses >> ABS_MT_TRACKING_ID to do finger tracking. The fact of the device >> being able to track individual finger makes it possible to >> report touch events using MT-B. This patch adds the support >> for the driver to report MT-B and makes it configurable through >> module parameter so that existing codes that are relying on its >> MT-A implemtation don't get affected. > > Are there any such codes? Most systems, if not all, seem to use mtdev, > which can handle both protocols. I do not think a parameter switch is > a good idea. Switching to MT-B or leaving things as is look like the > viable options. Yes, let's just switch to MT-B :). Part of open source is that one can look at other implementations to figure out how to make your own new device work. We don't want to proliferate MT-A since MT-B is the way forward. In fact, I would also suggest preceding this patch with one that removes the switch to turn touch reporting on and off. It's really unnecessary. I bet no one in the world turns it off :). -- Chase