From alsa-devel-owner@alsa.jcu.cz  Fri Dec  4 00:02:30 1998
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Date: Fri, 4 Dec 1998 00:02:26 +0100 (CET)
From: Jaroslav Kysela <perex@jcu.cz>
To: Martin Pahl <pahl@tnt.uni-hannover.de>
cc: alsa-devel@alsa.jcu.cz
Subject: Re: Driver for Zefiro Acoustics ZA2
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On Thu, 3 Dec 1998, Martin Pahl wrote:

> Hallo,
> 
> I have a driver for Zefiro Acoustics ZA2 and I would like to integrate
> it into ALSA. I read the description to ALSA-kernel-library, but I'm
> not quite sure where to start. The ZA2 uses a DSP CS4920. But it's not
> acessable directly from the PC. Probably a module for the CS4920 does

I'm not sure if separate code doesn't make sense. This DSP chip could be
used in another soundcard, isn't true? You can simply do all i/o
operations via callbacks which should be initialized at driver start with
proper (soundcard specific) i/o routines. You can look for example to
alsa-driver/lowlevel/generic/ac97_codec.c source. Here isn't any direct
i/o operation, thus this code could be used from many lowlevel drivers.

> not make sence. The ZA2 uses ISA-DMA for transferring data from/to the
> PC. How does the ALSA-kernel-library support ISA-DMA beyond those two
> functions snd_dma_program and snd_dma_residue? Which devices must be

These two functions fully cover ISA DMA operation. You don't need other
routines for ISA DMA control.

> created? The ZA2 has a digital I/O-interface only. Probably a mixer
> device does not make sence. MIDI is not available. 

ALSA can have soundcard with PCM device(s) only, of course. You simply
don't assign other devices to soundcard.

Probably best way how to write new driver is modify some existing.
Better documentation is on the way and I'm ready answer some questions.

Welcome in ALSA project!

							Jaroslav

-----
Jaroslav Kysela <perex@jcu.cz>
Academic Computer Centre, University of South Bohemia
Branisovska 31, C. Budejovice, CZ-370 05 Czech Republic



