| [AD] ALSA and dmix - small fix |
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My troubles with arts, and Elias post about his Jack driver prompted me
to try ALSA and dmix again. With its dmix plugin, ALSA can be setup to
do software mixing. Until recently, very few programs actually worked
with a dmixed ALSA, but the situation is getting better.
I tried the ALSA driver of allegro 4.1.14 with dmix. Although
install_sound() succeeded, the exstream example didn't produce any
sound, and stayed forever on "update #1".
After tweaking the driver a bit, it turned out that after
initialization, ALSA was on the state "SND_PCM_STATE_SUSPENDED". Adding
"snd_pcm_start(pcm_handle)" in the initialization of the driver made
it work perfectly. I attached the corresponding one-line patch. I'm no
expert on ALSA, so whoever wrote the driver should check that this won't
break anything... it however seems harmless enough!
This patch isn't needed when ALSA isn't dmixed, but according to the
docs, it might be. From what I gather, a dmixed ALSA is much stricter,
and "incorrect" code that was tolerated before isn't anymore. This is
why a lot of programs like KDE, xine and xmms needed to be updated
before they would work with a dmixed ALSA.
As KDE 3.2.2 works on a dmixed ALSA, I don't need arts anymore, and this
is a very good thing :-).
--
Julien Cugnière
--- alsa9.c.old 2004-05-16 15:25:46.280896848 +0200
+++ alsa9.c 2004-05-16 15:24:11.308334872 +0200
@@ -443,6 +443,7 @@
alsa_rate, uconvert_ascii((alsa_stereo ? "stereo" : "mono"), tmp2));
digi_driver->desc = alsa_desc;
+ snd_pcm_start(pcm_handle);
return 0;
Error: