From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Graham <johngavingraham@googlemail.com>
Subject: Re: Access to bytes from the raw audio stream? (AC'97)
Date: Wed, 3 Feb 2010 16:27:05 +0000
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	<20100203161737.GC12034@sirena.org.uk>
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> With a lot of AC97 controllers the hardware won't allow you direct
> access to the cooked wire data, you'll only be able to see decoded audio
> streams. =A0What is it that you're actually trying to do?

Basically, we've got a problem where we think our processor is
bit-shifting the sample for some reason, and I was going to see if I
could either (i) un-bit-shift it (it looks like we're not actually
losing any data, the sound's just being multiplied by 2^4), or (ii)
reproduce the problem we see by bit-shifting the samples on a
known-good platform.


> For embedded platforms you mostly want to look under sound/soc though
> there are a few platforms outside of there.

I know the drivers for our particular setup (UBC1400 codec/i.MX25
processor) are under sound/arm, but I'm not sure if there's anything
in there that actually sees the samples as they come through.


Would I be able to access samples quite early on in the generic AC'97
code (I don't know where that is, either, but it would be interesting
to see, at least :p)

Thanks,

John G