From mboxrd@z Thu Jan 1 00:00:00 1970 From: Liam Girdwood Subject: Re: UCM representation questions Date: Fri, 27 May 2011 10:20:23 +0100 Message-ID: <4DDF6CD7.2070903@ti.com> References: <74CDBE0F657A3D45AFBB94109FB122FF0498A47E52@HQMAIL01.nvidia.com> <4DD7E644.4010301@ti.com> <74CDBE0F657A3D45AFBB94109FB122FF0498A485B6@HQMAIL01.nvidia.com> <4DDE3333.5010907@ti.com> <74CDBE0F657A3D45AFBB94109FB122FF0498A486ED@HQMAIL01.nvidia.com> <20110527013153.GA21016@opensource.wolfsonmicro.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from comal.ext.ti.com (comal.ext.ti.com [198.47.26.152]) by alsa0.perex.cz (Postfix) with ESMTP id BA803103AF9 for ; Fri, 27 May 2011 11:20:25 +0200 (CEST) In-Reply-To: <20110527013153.GA21016@opensource.wolfsonmicro.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: Mark Brown Cc: "alsa-devel@alsa-project.org" , Stephen Warren List-Id: alsa-devel@alsa-project.org On 27/05/11 02:31, Mark Brown wrote: > On Thu, May 26, 2011 at 10:13:21AM -0700, Stephen Warren wrote: > >> My thought process here was that conflicting devices are probably less >> common than non-conflicting devices. At least, it seems like that'd be >> the default assumption of someone writing a UCM file. So, if we list >> ConflictingDevice(s), then that would often map to an empty list, and >> you could eliminate the section. If we had to list all compatible >> devices, by default you'd have to list every device in the UCM verb in >> almost all cases. That seems like more work. > >> Plus, adding an optional ConflictingDevice list maintains backwards >> Compatibility with any existing UCM files, whereas adding a mandatory >> SupportedDevice list doesn't. > > I tend to agree with this - the usual case is that you can have as many > devices as you like running, the reason for restricting things is more > normally usefulness rather than physical possibility. > >> I wonder if allowing all lists of devices to be either inclusive >> SupportedDevice or exclusive ConflictingDevice makes sense, with the >> default being ConflictingDevice being empty, and SupportedDevice being >> the entire set of devices? Seems more complex, but probably still >> workable. > > That makes sense too - if either directive is used we require an > explicit list, otherwise we assume everything is compatible. Ok, sounds fine to me too. I just wanted to make sure we had explored both options here. Thanks Liam