Question about surround default pin config

Question about surround default pin config

[David Henningsson]

Hi,

Sometimes it's better to just ask than getting confused trying to figure 
it out yourself.

When you have 2 stereo pairs of line-out or speaker, they are meant as 
either 4.0 (front left, front right, rear left, rear right), and 
sometimes they are meant as 2.1 (front left, front right, unused, lfe).

We should support both variations, I assume.

What is really the way to write my pin fixups to specify either 4.0 or 
2.1? Are there any de-facto standards?

If I look at e g check_output_sfx (in hda_auto_parser.c), it looks like 
it would be impossible to have 2.1, i e, impossible to have LFE without 
also having rear left and rear right. But I might be missing something?

-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic

Re: Question about surround default pin config

[Takashi Iwai]

At Thu, 09 Aug 2012 14:51:40 +0200,
David Henningsson wrote:
> 
> Hi,
> 
> Sometimes it's better to just ask than getting confused trying to figure 
> it out yourself.
> 
> When you have 2 stereo pairs of line-out or speaker, they are meant as 
> either 4.0 (front left, front right, rear left, rear right), and 
> sometimes they are meant as 2.1 (front left, front right, unused, lfe).
> 
> We should support both variations, I assume.
> 
> What is really the way to write my pin fixups to specify either 4.0 or 
> 2.1? Are there any de-facto standards?
> 
> If I look at e g check_output_sfx (in hda_auto_parser.c), it looks like 
> it would be impossible to have 2.1, i e, impossible to have LFE without 
> also having rear left and rear right. But I might be missing something?

Right, as of now, 2.1 configuration isn't supported by the parser.
It's a bit messy.  We can check the associated number whether it's 4.0
or 2.1, but I don't think there is a strict definition to
differentiate between them.  So, it'd end up with a guess work.

Of course, we can add some special flag beforehand and let auto-parser
handle 4.0 as 2.1.


Takashi