From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH 2/2] input: mt: Document the MT event slot protocol (rev3) Date: Fri, 21 May 2010 10:41:40 -0700 Message-ID: <20100521174140.GA23155@core.coreip.homeip.net> References: <1274457354-5570-1-git-send-email-rydberg@euromail.se> <4BF6B673.1080507@euromail.se> <20100521165218.GA26439@core.coreip.homeip.net> <4BF6BB43.2020405@euromail.se> <20100521172222.GB26439@core.coreip.homeip.net> <4BF6C303.7030804@euromail.se> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pv0-f174.google.com ([74.125.83.174]:38189 "EHLO mail-pv0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933449Ab0EURlq (ORCPT ); Fri, 21 May 2010 13:41:46 -0400 Content-Disposition: inline In-Reply-To: <4BF6C303.7030804@euromail.se> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Henrik Rydberg Cc: Ping Cheng , Andrew Morton , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Mika Kuoppala , Peter Hutterer , Benjamin Tissoires , Stephane Chatty , Rafi Rubin , Michael Poole On Fri, May 21, 2010 at 07:29:39PM +0200, Henrik Rydberg wrote: > Dmitry Torokhov wrote: > > On Fri, May 21, 2010 at 06:56:35PM +0200, Henrik Rydberg wrote: > >> Dmitry Torokhov wrote: > >>> On Friday 21 May 2010 09:36:03 am Henrik Rydberg wrote: > >>>> Ping Cheng wrote: > >>>>> Hi Henrik, > >>>>> > >>>>> Thank you for your quick turnaround. Two minor comments in line. > >>>>> > >>>>> Ping > >>>> Thanks for those, yes, both mistakes. Dmitry, in case you find these last > >>>> versions acceptable, perhaps one could change them manually: > >>>> > >>>> 1. Patch description: s/SYN_MT_SLOT/ABS_SLOT/ > >>> Not ABS_MT_SLOT? > >> I wrote an argument for ABS_SLOT in the first patch, in short there is a > >> namespace clash I would like to avoid. > >> > > > > Hm, I am not sure I follow that argument. While you are saying that slot > > is not an MT event it is certainly not an ST event either. I would even > > say that slot _is_ an MT event since it signals current "slot" or group > > of MT data to userspace. Am I missing something? > > > > It is really a SYN or control event, since it sets which slot is currently being > updated. However, as argued earlier in this thread, since the presence and value > range of the slot variable is needed in user space, converting it to an ABS > event makes sense. But ABS_SLOT is not a property of the slot, and is thus not > an MT event in that respect. Currently, all ABS_MT events are either bypassing > filtering altogether, or (with these patches) being routed via a slot. The > naming convention ABS_MT is the only clue to user space that this is event will > appear once per slot. I think it should remain that way. > I guess this is where our disconnect lies as when I am looking at the event names I view all *_MT_* events as related to the multitouch protocol handling. -- Dmitry