ICH7 soundcard (82801G, not 82801GB) support?

[Dmitry Pryanishnikov]

Hello!

On Sat, 25 Mar 2006, Anders Nordby wrote:
>> Our sound system doesn't support HD audio yet. I've started to look into
>> it several times since this would work on new VIA chips as well, but I
>> keep getting ENOTIME :}
>
> I thought all the HD audio cards had a fall-back possibility. I just
> want sound to work at all. In ich.c, ICH5/6/7 has a note "needs to be
> treated as ICH4", and in ich_devs these are marked PROBE_LOW.

  I also thought that way once, but it's not true. Actually ICH6/7 have
both sound engines: old AC'97 and new HDA (ICH5 has only AC'97). Sound
engines share chipset physical output lines, and thus only one of them
can be used on particular motherboard - it depends on what is soldered
to these lines. Mobo's BIOS disables unused device (AC'97, HDA or both)
and there is no way to reenable it until reset (_and_ there is no
point in doing so - HDA codec won't work with AC'97 engine).
Intel's PDF for ICH6 clearly says (see page 51 of Document Number
301473-002):

  Intel High Definition Audio Controller

  The Intel High Definition Audio specification defines a digital interface
  that can be used to attach different types of codecs, such as audio and
  modem codecs. The ICH6 Intel High Definition Audio digital link shares pins
  with the AC-link. Concurrent operation of Intel High Definition Audio and
  AC'97 functionality is not supported.

So for now, if you have ICH6/7-based card/mobo, and it uses HDA-codec
(not AC'97), FreeBSD doesn't support it.


Sincerely, Dmitry
-- 
Atlantis ISP, System Administrator
e-mail:  dmitry at atlantis.dp.ua
nic-hdl: LYNX-RIPE