[ltp] sound probs (fwd)

[Peter Soderling]

This was some good help so I wanted to forward it to the list . . .

--petesoder


---------- Forwarded message ----------
Date: Tue, 09 Nov 1999 16:31:22 -0500
From: Valery Trifonov <trifonov@cs.yale.edu>
To: pete@lighthousecs.com
Subject: Re: [ltp] sound probs

Pete,

Excuse the private reply, I have a solution for TP600 (RH6.0) which may
or may not work on 770X so I didn't want to add noise to the mailing
list. If it works for you, please report the results to the list.

First, check that you have kernel messages saying "Sound: DMA (output)
timed out - IRQ/DRQ config error?" in /var/log/messages. If not, your
problem may be different.

Next make sure the sound modules are given the correct parameters in
/etc/conf.modules, specifically that the "irq" and "mpuirq" parameters
of the cs4232 module match your hardware configuration. If you have
doubts about your hardware configuration, consult the Windows device
manager. IIRC the pre-set CS4239 IRQ is 5 and the IRQ for the MPU-401 is
9; but I've changed mine, and you have a 770X so it may be different.

If the setup is correct, then my conjecture is you have installed the
PCMCIA package, and its I/O port scan disconfigures the sound hardware.
Other people have suggested unloading and reloading sound modules. I
know of two more ways to solve this:

(1) Set the CORE_OPTS parameter in /etc/sysconfig/pcmcia to
"probe_io=0". This will tell the PCMCIA cardmgr to skip the IO port scan
at boot. The downside is that when you insert a PC card the manager may
assign to it IO ports which are already in use by other hardware. To
avoid this you have to list all pre-assigned ports in
/etc/pcmcia/config.opts.

(2) Go in /etc/rc.d/rc.sysinit, find the line

	# load sound modules

and comment out (or otherwise disable) the if-fi block following it.
This will skip the loading of sound modules at boot, and will let the
PCMCIA cardmgr do its scan before the sound hardware has been
initialized. Whenever you first use sound, the sound modules will be
loaded on demand and initialized, which sets the CS4239 registers
correctly.

I used first (1), then (2) and I've had no problems with the sound
since... except when I resume from suspend/hibernation; I've almost
solved that problem, too, but that's a different story.

Please try this and let me know if it doesn't work; if it works, please
post to the list.

Regards,
Valery

----- The Linux ThinkPad mailing list -----
The linux-thinkpad mailing list home page is at:
http://www.bm-soft.com/~bm/tp_mailing.html