[alsa-devel] Disable DAPM for click avoidance ?

[Ricard Wanderlof]

On Thu, 23 Nov 2017, Mark Brown wrote:

> > In my case the codec is only a couple of years old, so I'd say it 
> > qualifies as 'modern'. There's a table in the data sheet describing the 
> 
> Wow, people are still designing new VMID based CODECs - what is this one?

In this case it's the AK4637. From the data sheet it looks to be from 
2015.

I know there are codecs that do not need their inputs/outputs (internally) 
biased to a VMID, but have a 0V bias level using an internal charge-pump 
design to generate the required internal negative voltages, if that is 
what you're thinking of. One disadvantage from a cost perspective is the 
external capacitors needed for the charge pump to operate, and the design 
in which this one is used is extermely cost optimized.

> > During which time period is the digital mute enabled? From the first 
> > stream startup until everything is up and running?
> 
> It should be enabled at all times that we're not actively playing
> anything.  

Ok. So it really would be the last callback made (with mute = off) to the 
codec driver once everything else has been set up then?

/Ricard
-- 
Ricard Wolf Wanderlöf                           ricardw(at)axis.com
Axis Communications AB, Lund, Sweden            www.axis.com
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