From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: soc-dsp programming model for loopbacks Date: Wed, 25 Jan 2012 20:14:39 +0000 Message-ID: <20120125201438.GA17032@opensource.wolfsonmicro.com> References: <4f1f2489.c602440a.208e.ffff9d7bSMTPIN_ADDED@mx.google.com> <1327511249.11901.37.camel@odin> <20120125171112.GR3687@opensource.wolfsonmicro.com> <002d01ccdb9c$7099f1e0$51cdd5a0$@bossart@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from opensource.wolfsonmicro.com (opensource.wolfsonmicro.com [80.75.67.52]) by alsa0.perex.cz (Postfix) with ESMTP id 7E5E3103823 for ; Wed, 25 Jan 2012 21:14:41 +0100 (CET) Content-Disposition: inline In-Reply-To: <002d01ccdb9c$7099f1e0$51cdd5a0$@bossart@linux.intel.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: Pierre-Louis Bossart Cc: alsa-devel@alsa-project.org, 'Liam Girdwood' List-Id: alsa-devel@alsa-project.org On Wed, Jan 25, 2012 at 12:03:42PM -0800, Pierre-Louis Bossart wrote: > > That's what the CODEC<->CODEC stuff is all about, hiding the link from > > userspace. > I can see how this would simplify the loopback part, but doesn't it make the > 'regular' playback/capture functionality more complex? If my DSP is seen as > a CODEC, how do I represent the CPU-DSP interface (DMA or shared memory)? You'd need a DAI for that interface but you'll need that no matter what you do, it'll just be a very simple DAI that needs no configuration for things like AIF format. With the soc-pcm setup you also need the front and back end DAIs so it's about the same, the benefit comes at runtime. My primary focus for the CODEC<->CODEC links is actually things like basebands rather than on-SoC DSPs, it's just that if the hardware can be thought of in the same way it should simplify things a little.