[alsa-devel] [PATCH] Add ASoC WM9713 codec driver.

Clemens Ladisch cladisch at fastmail.net
Tue Nov 20 13:02:00 CET 2007

Takashi Iwai wrote:
> Mark Brown wrote:
> > +#define WM9713_PCM_FORMATS \
> Is it S24_LE or S24_3LE?  I see S24_LE in other codec drivers, but am
> not pretty sure whether I checked it...

Apparently, these are the formats that an AC'97 controller connected
with this codec can support.

Samples on the AC'97 bus are always MSB-aligned with at most 20 bits.
I don't think it makes much sense to let the codec driver decide what
sample formats the controller should support, because the controller
will have to convert the samples anyway (from/to 16, 24 or 32 bits).
Furthermore, I'm sure there are AC'97 controllers that can handle big-
endian samples on the memory bus.


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