[alsa-devel] UCM: Possible snd_use_case_get enhancements
swarren at nvidia.com
Fri Jun 3 23:11:35 CEST 2011
The recent patches I posted allow querying a modifier/device's supported/
conflicting device list from a modifier/device either within the
currently active verb (if any) or an explicitly defined verb.
I figured a similar enhancement to snd_use_case_get might be useful; i.e.
to allow querying within a specific verb, and also to indicate that one
shouldn't fall back to a verb, or overall values. I'd propose something
The "=" would prevent fallback to a "higher" object if present. So for
Current verb, not from device or modifier, with fallback to verb and
Current verb, from device/modifier with fallback to verb and
Current verb, from dev/mod without fallback to verb or ValueDefaults:
Specify a verb and dev/mod, but allow fallback to verb or ValueDefaults:
Specify a verb and dev/mod, but no fallback to verb or ValueDefaults:
One can also query from just a verb, with/without fallback:
Or current verb with no fallback:
Does this seem useful, and a sane query string syntax?
An alternative would be to drop the added "=" stuff, and never auto-
fallback. However, that'd be a regression relative to current
functionality, force clients to implement fallback themselves, and make
querying ValueDefaults hard.
More information about the Alsa-devel