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From: Lars-Peter Clausen <lars@metafoo.de>
To: Qiao Zhou <zhouqiao@marvell.com>, Mark Brown <broonie@kernel.org>,
	"tiwai@suse.de" <tiwai@suse.de>,
	alsa-devel@alsa-project.org
Subject: Re: [DAPM question] DAPM support for single input multiple outputs
Date: Mon, 09 Mar 2015 09:53:50 +0100	[thread overview]
Message-ID: <54FD5F9E.3080606@metafoo.de> (raw)
In-Reply-To: <54FD5C1D.9030909@marvell.com>

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

  reply	other threads:[~2015-03-09  8:53 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-09  8:38 [DAPM question] DAPM support for single input multiple outputs Qiao Zhou
2015-03-09  8:53 ` Lars-Peter Clausen [this message]
2015-03-09 11:16   ` Qiao Zhou
2015-03-09 12:20     ` Mark Brown
2015-03-10  1:56       ` Qiao Zhou

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