From mboxrd@z Thu Jan 1 00:00:00 1970 From: Liam Girdwood Subject: Re: soc-dsp programming model for loopbacks Date: Thu, 02 Feb 2012 11:17:52 +0000 Message-ID: <1328181472.3974.5.camel@odin> References: <4f1f2489.c602440a.208e.ffff9d7bSMTPIN_ADDED@mx.google.com> <1327511249.11901.37.camel@odin> <1328087231.1610.28.camel@vkoul-udesk3> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from na3sys009aog107.obsmtp.com (na3sys009aog107.obsmtp.com [74.125.149.197]) by alsa0.perex.cz (Postfix) with ESMTP id 3B84424512 for ; Thu, 2 Feb 2012 12:17:57 +0100 (CET) Received: by wgbdt10 with SMTP id dt10so1913257wgb.25 for ; Thu, 02 Feb 2012 03:17:54 -0800 (PST) In-Reply-To: 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: Vinod Koul Cc: alsa-devel@alsa-project.org, Mark Brown , Pierre-Louis Bossart List-Id: alsa-devel@alsa-project.org On Wed, 2012-02-01 at 11:50 +0000, Girdwood, Liam wrote: > On 1 February 2012 09:07, Vinod Koul wrote: > > On Wed, 2012-01-25 at 17:07 +0000, Liam Girdwood wrote: > >> We could eventually remove steps 2 and 4 for the FE DAI link, and look > >> at hard coding the hw_params() in the mach driver for the loopback > >> link. > >> That way the only user space driven actions would be to configure the > >> mixers in the CODEC and DSP for the correct route. DAPM would then > >> detect the path and Dynamic PCM would use the hard coded configuration > >> or bespoke mach driver logic to configure the loopback DAI link based > >> on > >> use case. This would have to be done after the basic Dynamic PCM > >> infrastructure was upstream though (unless you have a patch atm). > > Hi, > > Sorry to join the party late :-) > > > No worries ;-) > > > Liam, if we configure the hw_params in the machine driver statically, > > represent the DSP using a map along with a codec kind of modeling. > > In OMAP we reconfigure (or fixup) some of the hw_params() in the machine driver for a BE DAI link that cant operate at the requested FE params. The ABE takes care of any conversion though. > > Would the BEs be triggered on from soc_dsp_runtime_update() when the > > loopback is established thru the DSP. > > This way we avoid all the "virtual" FEs. Use loopback to turn on codec > > and DSP (thru BEs) > > > > Would this make sense, or I need more coffee :) In the code base atm we have to use a FE pcm to trigger the BE loopback DAIs. however, the intention is to use Mark's CODEC <-> CODEC DAI link work to support the loopback with hard coded params in the machine driver. This would save the need for any FE pcm operations. Regards Liam > > > > -- > > ~Vinod > > >