Fwd: [OLPC-devel] Geode GIT Tree

[Jordan Crouse]

On 16/06/06 17:14 -0600, Tom Sylla wrote:
> Jordan Crouse wrote:
> >On 16/06/06 15:43 -0700, Mark J. Foster wrote:
> >>Hi, Chris!
> >>
> >>If the mic in jack does not work with a mic, but it does work with a 
> >>line input, then the audio driver has probably not properly enabled the 
> >>AD1888's external VRef output, which supplies power to the microphone.
> >
> >Do we have details (specs)?  That sounds like a pretty simple change we
> >can toss in to see if it has an effect.
> 
> Its in the datasheet:
> 
> http://www.analog.com/en/prod/0,2877,AD1888,00.html
> 
> Table 43. Miscellaneous Control Bit Register (Index 76h)
> 
> VREFD and VREFH.
> 
> The reset value for VREFD looks correct, though, so I don't know if that 
> is really the problem (or maybe the driver is smashing things it shouldn't)

What should VREFH be set to?   From the look of things, the Linux driver
is setting LOSEL, HPSEL, MSPLT and AC97NC, and leaving everything else as
the default (VREFH default being 2.2V output).  If we need to change
anything, it will be a super easy change.

Jordan

-- 
Jordan Crouse
Senior Linux Engineer
Advanced Micro Devices, Inc.
<www.amd.com/embeddedprocessors>