ATI IXP development

[Pyun YongHyeon]

On Fri, Jan 07, 2005 at 04:03:02PM +0100, matricks at teepop.net wrote:

[...]
 > > 
 > > Glad to see a someone who can write new audio driver.
 > > It seems that the datasheet of AD1888 is publicly available.
 > > So I guess you can release the driver under BSD license.
 > > http://www.chipcatalog.com/Analog/Datasheet/AD1888.htm
 > > 

[...]

 > 
 > I'm not sure I can write it. Never written a driver before but I've coded C/C++
 > for many years and have basic understanding how drivers work and how to develop
 > them. Somewhere you have to take the first step and this seams like a good place
 > to start.
 > 

Hmm.. If I had the hardware I would have tried to write a new driver.
As you know, FreeBSD lacks a few driver for recent sound hardwares.
I'd like to change this but all hardware I got is old/discontinued
one and no new driver was needed except cs4231 on sparc64.

 > I looked at the atiixp driver for ALSA and one of the FreeBSD AC'97 drivers and
 > I don't see why I shouldn't be able to peice something together. If you have
 > some information that I should read except the Developers Handbook, please
 > enlighten me.
 > 

AD1888 Codec support could be added into ac97 support code.  But I
don't know you got a copy of ATI IXP200 datasheet. If the datasheet
is not avilable you have to guess its register layout/usage from
linux driver. Direct porting linux driver to FreeBSD may be possible
but I don't like GPL'ed source codes contaminate our tree. Of course,
the driver can live in ports tree but maintaining kernel driver in
ports tree is endless pain to driver maintainer.

While writing cs4231 driver on sparc64 I read existing driver code
in sys/dev/sound/pci directory. You may also want to see sound
subsystem, bus dma and locking section in Architecture Handbook.
All new drivers should be MP-safe.

 > .magnus auvinen
-- 
Regards,
Pyun YongHyeon
http://www.kr.freebsd.org/~yongari	|	yongari at freebsd.org