[alsa-devel] [PATCH v5] ASoC:Add support for cs42l73 codec

Mark Brown broonie at opensource.wolfsonmicro.com
Thu Oct 20 23:28:45 CEST 2011


On Thu, Oct 20, 2011 at 08:26:11PM +0000, Austin, Brian wrote:

Fix your mailer to word wrap within paragraphs, I've reflowed for
legibility.

> We have only 2 power domains.  The input PCM and the output AMP.
> The routing between these 2 points in the codec is handled by volume levels.

Like I say this is pretty unremarkable - the volumes are your DAPM
routing controls.

> Given that, why would there be a need to show all routes through the
> mixer in a DAPM context? How do you show that?  would it look
> something like this?

Well, the most obvious issue is that even if your device doesn't have
any useful internal power management there may be external devices
connected to the outputs (eg, a high power speaker amp) which do and so
we need to know which outputs are actually active in order to control
the outputs.

> {"HPOUT",  NULL, "HP Amp"}
> {"HP Amp", "Amp Switch",  "DAC1"}
> {"DAC1",  "HP-XSP Volume Control",  "XSPIN"}

This looks wrong, the control on the DAC looks like it actually controls
just the one input path.

> You can represent the "HP-XSP Volume Control" control as DAPM? 

Yes.


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