From mboxrd@z Thu Jan 1 00:00:00 1970 From: Qiao Zhou Subject: Re: [DAPM question] DAPM support for single input multiple outputs Date: Mon, 9 Mar 2015 19:16:18 +0800 Message-ID: <54FD8102.7020503@marvell.com> References: <54FD5C1D.9030909@marvell.com> <54FD5F9E.3080606@metafoo.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from mx0a-0016f401.pphosted.com (mx0a-0016f401.pphosted.com [67.231.148.174]) by alsa0.perex.cz (Postfix) with ESMTP id 8A2112605C6 for ; Mon, 9 Mar 2015 12:16:22 +0100 (CET) In-Reply-To: <54FD5F9E.3080606@metafoo.de> 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: Lars-Peter Clausen Cc: "tiwai@suse.de" , "alsa-devel@alsa-project.org" , Mark Brown List-Id: alsa-devel@alsa-project.org On 03/09/2015 04:53 PM, Lars-Peter Clausen wrote: > 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. I'll have a try to specially handle demux type. Thanks for the suggestions. BTW, is there plan to add demux support? > > - Lars > -- Best Regards Qiao