From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lars-Peter Clausen Subject: Re: [DAPM question] DAPM support for single input multiple outputs Date: Mon, 09 Mar 2015 09:53:50 +0100 Message-ID: <54FD5F9E.3080606@metafoo.de> References: <54FD5C1D.9030909@marvell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp-out-061.synserver.de (smtp-out-074.synserver.de [212.40.185.74]) by alsa0.perex.cz (Postfix) with ESMTP id EF1A32605C4 for ; Mon, 9 Mar 2015 09:53:44 +0100 (CET) In-Reply-To: <54FD5C1D.9030909@marvell.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Qiao Zhou , Mark Brown , "tiwai@suse.de" , alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org On 03/09/2015 09:38 AM, Qiao Zhou wrote: > Hi Mark, > > I have one question and need your suggestion. Thanks in advance. > > In our DSP, one stream path is like this: There is one bit controlling > whether a signal A goes to A_out or B_out. That's the reverse case of > DAPM_MUX(multiple inputs, single output). > > One way is to use two switches but it seems not good since two switches > control the same bit. It's strange. Do you have any opinion about such > requirement support? There is currently no support for a demux. But it shouldn't be too hard to add one in the DAPM core, if you want to take a try at it. A demux would behave very similar to a mux, except that you'd reverse sources and sinks. The only thing that is a bit tricky is that we only have one control element per path and currently it always belongs to the sink. For a demux it needs to be long to the source. This means you can't have a mixer directly connected to the same path as a demux and the core needs to make sure that that doesn't happen. - Lars