microphones pin cfg under Linux on Apple macbook air 1,1

[nicolo.p]

Hello

I need to understand better how Apple OS X handles the microphone pins (both external and internal front mics) on this MBA1,1, in order to make them work under linux+alsa

In particular, there is this `.plist` which I don't understand very well:

[code=auto:0]
<dict>
<key>MicAttributes</key>
<integer>28</integer>
<key>MicInfo</key>
<string>Sampled on rising edge</string>
<key>NodeID</key>
<integer>39</integer>
<key>PinConfigDefault</key>
<integer>2426405136</integer>
</dict>
[code=auto:0]

Since I'm trying to set correctly the mic pins for this ALC885 under Linux, and I don't have a node at `0x27=39` (at least not that hda-analyzer sees), it's not surprising that if I send the corresponding verbs to `GET_CONFIG_DEFAULT` I don't get anything.As for the sampled on rising edge, I don't know how to use this info.

Does anyone know how Apple handles this, e.g. if they have a node virtually implemented in the driver, or does anyone happen to know about vendor-specific verbs like COEF setup or tweaks in the driver level (mostly provided from external file)?

 

More data on the general problem here http://superuser.com/questions/646470/microphones-not-working-on-apple-macbook-air-1-1-early-2008-under-linux?noredirect=1#comment848412_646470