Some people may be aware of problems with laptops and the cs423* chips
run on the ad1848.c driver. I have such a setup in my Dell Inspiron 3500
laptop computer. The sound driver fails to work after the first time the
system is put into suspend mode by closing the laptop's cover. The sound
becomes broken, stuttering or ending early. "dmesg" reports DMA/DRQ
configuration problems. The computer has to be power cycled in order to
get the sound working again, though some commercial drivers can handle
the suspend.
Chris Studholme (Chris.Studholme@ualberta.ca) has a web page at:
http://www.bus.ualberta.ca/cstudhol/unix/inspiron.html
in which he describes a hack which fixes the problem for him. I've tested
it, and found that it works for my laptop. A cursory examination of the
kernel logs suggests that it works by forcing the sound hardware into
8-bit soundblaster compatibility mode, then switching back into native
mode. This seems to get the hardware back in a useful state.
It occurs to me that someone might want to see if there's some way to
embed a similar functionality in the ad1848.c driver code, so that if the
sound fails, the hardware can be toggled into soundblaster mode and back
again. Right now, I've got a small script which is run by apmd whenever
the system resumes from a suspend, but I gather that this problem is very
common on laptops, and not just on Dell, judging by the number of people
with problems on dejanews. Having the driver fix itself would be nice for
those people.
-- Christopher Neufeld neufeld@physics.utoronto.ca Home page: http://caliban.physics.utoronto.ca/neufeld/Intro.html "Don't edit reality for the sake of simplicity"- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/