29-rc2 remaining breakage / ALSA

Andy Green andy at openmoko.com
Sun Feb 1 17:51:35 CET 2009

Hash: SHA1

Somebody in the thread at some point said:

| But I think is related to the capture/playback device. The only big
| change seems the registration
| of the controls. The amixer dump gives us the answer I think.

Hm it seems the difference may be that before, that ALSA stuff used to
truncate the control name to 30 chars?

When I install FSO unstable on my SD card and then try alsactl restore
from the default /etc/asound.state that is installed, I see:

root at om-gta02:~# alsactl restore
alsactl: set_control:989: warning: name mismatch (Playback Mixer Voice
Capture Sw/Playback Mixer Voice Capture Switch) for control #68
alsactl: set_control:991: warning: index mismatch (0/0) for control #68
alsactl: set_control:993: failed to obtain info for control #68 (No
buffer space available)

And it's true when I look in that asound.state at #68 I see

\0x09control.68 {
\0x09\0x09comment.access 'read write'
\0x09\0x09comment.type BOOLEAN
\0x09\0x09comment.count 1
\0x09\0x09iface MIXER
\0x09\0x09name 'Playback Mixer Voice Capture Sw'
\0x09\0x09value false

However if I do an alsactl store, and look at #68 from the new
asound.state, I see

\0x09control.68 {
\0x09\0x09comment.access 'read write'
\0x09\0x09comment.type BOOLEAN
\0x09\0x09comment.count 1
\0x09\0x09iface MIXER
\0x09\0x09name 'Playback Mixer Voice Capture Switch'
\0x09\0x09value false

Just as it says, the name has evidently "changed" or at least is not
truncated any more.

If this is the issue then it just randomly affects ALSA controls with
"long names".

I dread to think about the hassle of making a new "dimension" of alsa
states based not only on device and hardware revision, but by kernel

So I will take a look at seeing if we can either change the names to be
truncated by definition or truncate them for compatability.

- -Andy
Version: GnuPG v1.4.9 (GNU/Linux)
Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org


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