On Fri, 20 Aug 2010, Stephen Warren wrote:
Jaroslav Kysela wrote:
On Thu, 19 Aug 2010, Stephen Warren wrote:
The Azalia controller on NVIDIA GPUs gives 4 ALSA hw devices:
(on card 1):
[swarren@swarren-lx2 ~]$ sudo aplay -l << includes hw=1,3 hw=1,7 hw=1,8 hw=1,9 >> ... all of which appear to work OK.
However, the list of available "PCMs" from aplay -L doesn't expose them all:
[swarren@swarren-lx2 ~]$ sudo aplay -L <<card 0 "Nvidia" elided>> hdmi:CARD=NVidia_1 HDA NVidia, NVIDIA HDMI HDMI Audio Output
Instead, I imagined that I'd see 4 PCMs listed by "aplay -L"; one for each converter. Is this an incorrect assumption? How would I make that happen?
There is a bug in alsa-lib to namehint.c. The code assumes that hw device number is similar to logical device numbers which is not true in case of your HDMI devices:
3, 7, 8, 9
The fallback code is used and only first logical device 0 is created.
Could you test this patch?
http://git.alsa-project.org/?p=alsa-lib.git;a=commitdiff;h=97d25c0766405453d...
I tested that, and unfortunately it doesn't seem to work; I get the exact same aplay -L output.
I debugged this a little, and see that add_card() is calculating the correct max_devices value for card=1 str=hdmi. However, in the loop that right after that calls try_config, when device=0, it returns 0, but when device=1, it returns -2 (-ENOENT). This happens inside try_config where it calls snd_config_search_definition (line 244 in latest git). At that point, buf is:
hdmi:CARD=NVidia_1,DEV=1
... which seems reasonable.
I'm a little confused about the device numbering though: The max_devices value is counting values "3, 7, 8, 9" and hence gets 9. However, the loop that calls try_config loops 0..max_devices-1, but bails out as soon as any error is found, thus disallowing "holes" in the numbering. That implies that "device" in that loop is a different numbering space? After I noticed that, I hacked that loop to continue instead of break on errors, and also removed the "err >= 0" condition from the loop, expecting that when device==3/7/8/9, try_config might work. In fact, 0 still works (of course) and 1..8 all fail with err=-2, so I assume at the same place in try_config.
See my description. It's assumed that the logical devices (hdmi:DEV=<logical_device>) are continous. Does 'aplay -D hdmi:CARD=NVidia_1,DEV=1' work in your system?
Jaroslav
----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.