From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick Lai Subject: Re: [alsa-devel] Compressed Audio Playback/Capture through ALSA framework Date: Wed, 16 Mar 2011 22:00:01 -0700 Message-ID: <4D819551.7090901@codeaurora.org> References: <4D7FB076.30300@codeaurora.org> <20110316103814.GA8369@sirena.org.uk> <1300273162.9428.10.camel@vkoul-udesk3> <20110316115627.GC14125@opensource.wolfsonmicro.com> <20110316175357.GB15605@opensource.wolfsonmicro.com> <20110316180828.GC15605@opensource.wolfsonmicro.com> <1300328500.9428.21.camel@vkoul-udesk3> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1300328500.9428.21.camel@vkoul-udesk3> Sender: linux-arm-msm-owner@vger.kernel.org To: "Koul, Vinod" Cc: Mark Brown , pl bossart , "linux-arm-msm@vger.kernel.org" , alsa-devel List-Id: alsa-devel@alsa-project.org On 3/16/2011 7:21 PM, Koul, Vinod wrote: > On Wed, 2011-03-16 at 23:38 +0530, Mark Brown wrote: >> On Wed, Mar 16, 2011 at 01:00:09PM -0500, pl bossart wrote: >>> On Wed, Mar 16, 2011 at 12:53 PM, Mark Brown >> >>>> It'd make the tie up with algorithms part much easier as we could have >>>> an interface for transferring the compressed data alone and then >>>> externally describe how that's plumbed into any other DSP that's going >>>> on and the physical outputs - it'd help with treating the data transfer >>>> as a standalone problem. >> >>> Still not convinced. Why would you need to 'externally describe' how >>> compressed data is linked to post-processing. It's all part of DSP >>> firmware, why should anyone care how the decoder provides data to >>> post-processes? You can control post-processes with ALSA controls as >>> for regular PCM. >> >> The problem is figuring out which controls are where and what can be >> joined up with what. This is a problem with regular PCM too but it gets >> much worse when everything is virtual. Media controller should provide >> a route to allowing applications to figure out what's going on in the >> hardware. > Wouldn't a virtual sound card solve this? I was thinking of representing > all DSP elements in a virtual card. I think it would work to certain extend but what if DSP can instantiate elements at run-time, how can we deal with this use case under current ALSA framework? -- Sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.