[alsa-devel] e-mu 1212m and 1820(m) patch

[James Courtier-Dutton]

Ctirad Fertr wrote:
> Dne sobota 12 květen 2007 10:46 James Courtier-Dutton napsal(a):
>> Nice work. Did you manage to do this from just the comments I had placed
>> in the source code, or did you use some other method?
> 
> I learned most part form the register names in emu10k1.h. They are quite self 
> explaining. 
> 
>> I would like to put enough comments in the source code so others, like
>> yourself, can add functionality that I have not had time to.
> 
> It would be nice.  There is another developer, Dustin, who I meet at local 
> linux forum. He tries to find a way how to add more 24 bit capture channels 
> then 8.  It is confusing, as we don't have enough informations about  
> connections between Hana and emu10k2. We belive EMU32 buses are 32bit and not 
> 16 bit.  The windows driver can record from (at least) 16 channels, anyway.
> Multichannel playback needs to be fixed as well.  We need a help or at least a 
> hint from you as you are only person who have datasheets. 
> 
> Regards,
> 
> Ctirad

The link between hana and emu10k2 is 32bit.
The link between the emu10k2 and the PCI bus for capture is 16bit and
limited to 16 channels. I decided to instead make this link 32bit, by
using 2 16bit channels, thus resulting in 16/2 = 8 channels.
I do have one datasheet that hints at a 24bit channel from emu10k2 and
the PCI bus, but I have not checked if the 1212m version of the emu10k2
supports it. It might only be the 1616m that supports it, and I have not
added support for that in alsa yet.

James