Driver for Realtek ALC56xx codec needed

[Martin Michlmayr]

The Realtek ALC56xx audio codecs are currently not supported by Linux
and I was wondering if the Linux Driver Project can help with this.
I briefly talked to Mark Brown, one of the main ALSA developers, to
see how hard a codec driver is and whether it might be in the scope
of LDP and he thought that a "CODEC driver for a simple CODEC would
be a fairly good project for them, actually".  Mark also offered help
(i.e. code review) if I can find someone who wants to work on the
driver.

Datasheets are available online.  For example, I found
http://www.realtek.cz/realtek-datasheet.php?datasheet=ALC5621
http://www.realtek.cz/realtek-datasheet.php?datasheet=ALC5623

Also, there is a Linux driver already (developed by Marvell):
http://kernel.ubuntu.com/git?p=marvell/dove-kernel/.git;a=blob;f=sound/soc/codecs/rt5623.c;h=9167e325aef799b0e0db5272d6cb692e94326e83;hb=refs/heads/lucid-mvl-dove-to-eric4
but it needs more work.  Mark Brown:
> The driver is in the ballpark of being OK for mainline.
> It needs updating for current styles of doing things, and
> general coding style stuff, but it's not a million miles off.
>
> If someoen posts it on the lsit I'll review it properly.
> Fixing the sort of stuff checkpatch can identify would be good first,
> though.

I can probably make a product available that uses the ALC5621 chip (a HP
t5325 Thin Client, for which I'd like to add Debian suppot and therefore
would like to see complete kernel support, including audio).  However,
to boot a kernel you'd ideally have a serial console which the device
doesn't offer, so you'd have to be able to make a 3V TTL RS232
converter; something like this: http://www.nslu2-linux.org/wiki/HowTo/AddASerialPort

Maybe you also have contacts at Realtek who could provide hardware or
help.

Anyway, according to
http://www.realtek.com.tw/downloads/downloadsView.aspx?Langid=1&PFid=39&Level=4&Conn=3&ProdID=159&DownTypeID=1&GetDown=false&Downloads=true
there are some other ALC56xx variants, most with a datasheet.  It would
be nice to see what the differences are and to support them all; but the
most important devices imho are the ALC5621 (used by the HP thin client)
and ALC5623 (apparently used by some upcoming devices).

Do you have someone interested in working on a driver for this codec?

Thanks,
-- 
Martin Michlmayr
http://www.cyrius.com/