From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755575AbaENR6r (ORCPT ); Wed, 14 May 2014 13:58:47 -0400 Received: from mail-pb0-f43.google.com ([209.85.160.43]:48537 "EHLO mail-pb0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751582AbaENR6a (ORCPT ); Wed, 14 May 2014 13:58:30 -0400 Date: Wed, 14 May 2014 10:58:25 -0700 From: Dmitry Torokhov To: simon@mungewell.org Cc: =?iso-8859-1?Q?=22Michal_Mal=FD=22?= , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, jkosina@suse.cz, elias.vds@gmail.com, anssi.hannula@iki.fi Subject: Re: [PATCH v4 01/24] input: Add ff-memless-next module Message-ID: <20140514175825.GA30089@core.coreip.homeip.net> References: <1398524543-15012-1-git-send-email-madcatxster@devoid-pointer.net> <1398524543-15012-2-git-send-email-madcatxster@devoid-pointer.net> <20140514063806.GC13621@core.coreip.homeip.net> <1818063.tFLKhAd1oy@sigyn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 14, 2014 at 11:11:40AM -0400, simon@mungewell.org wrote: > > > If we ever come across a really memoryless device it should not be > > particularly difficult to add another callback to ff-memless-next which > > would emulate conditional effects with constant force. > > It should be noted that some (/many?) applications/games already use the > CF with position feedback to emulate behaviour such as springs. The feed > back loop is simply not fast enough to do emulation of friction/inertia. > > I don't believe that the FF layer in the kernel should be 'tricked out' > with lots of emulation features. > > As a game designer (ok... tinkerer) it's a bit of a pain that devices lie > about what they can really do - ie. gamepads claiming periodic ability > when all they are doing is faking it with rumble. Would it help if kernel would indicate which effects are native and which are emulated? Thanks. -- Dmitry