From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [PATCH v3] ASoC: dapm - Add API call to query the widgets of valid DAPM paths. Date: Tue, 26 Jul 2011 15:37:34 +0100 Message-ID: <20110726143734.GG7285@opensource.wolfsonmicro.com> References: <1311588926-3439-1-git-send-email-lrg@ti.com> <20110725211620.GC6086@opensource.wolfsonmicro.com> <1311678996.4088.4.camel@CNA0741383> <20110726114117.GD7285@opensource.wolfsonmicro.com> <1311690414.2610.12.camel@CNA0741383> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from opensource2.wolfsonmicro.com (opensource.wolfsonmicro.com [80.75.67.52]) by alsa0.perex.cz (Postfix) with ESMTP id 84C8D1038E0 for ; Tue, 26 Jul 2011 16:37:36 +0200 (CEST) Content-Disposition: inline In-Reply-To: <1311690414.2610.12.camel@CNA0741383> 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: Liam Girdwood Cc: "alsa-devel@alsa-project.org" List-Id: alsa-devel@alsa-project.org On Tue, Jul 26, 2011 at 03:26:54PM +0100, Liam Girdwood wrote: > On Tue, 2011-07-26 at 13:41 +0200, Mark Brown wrote: > > OK, right. If we want to do that then a substantial proportion of the > > existing CODEC drivers are broken - they're routinely putting in the > > stream name they want to match against rather than adding extra text to > > the stream to give unique names that are never used. > They should all be OK, the stream event performs a strstr() on each > stream widget so will match left/right etc streams based on the DAI > stream name. The case I'm worried about is the case where we've got two widgets with identical stream names - left and right AIF both call their playback widget stream "Playback" or whatever. > > It does feel like this ought to be looking things up by widget rather > > than by stream, though. Widget names are already guaranteed unique and > > if the users do want to look things up for a single widget only it seems > > to make sense to ask for that widget rather than ask for a stream as > > it's not how we're currently using streams. It feels like if we're > > asking for a stream we should do the same substring multi-match that we > > do when pushing events into them. > V2 did the substring match, although now that more complex hardware is > appearing I wonder if we should connect DAIs to widgets with the widget > name (rather than just relying on the substring). i.e. each DAI could > have a list of AIF widgets (most would have 1 or 2). Both methods could > co-exist for a while with the substring method being deprecated. Yes, there's definitely room to improve here - one thing I'd like to see is a system for mapping individual channels in the played audio so if for example we're playing mono data (or stereo data on a 5.1 CODEC) then we can figure out that lots of the channels aren't actually in use and not power them on.