At Thu, 23 Jun 2011 09:01:33 +0200, Clemens Ladisch wrote:
Mark Brown wrote:
We need some way for userspace to figure out that a jack exists and that it contains multiple functionalities from multiple subsystems. If we have a proposal for how we do that which seems viable then great, but we don't have that yet.
Last November I posted a patch to add ALSA entity types to the media API; it stalled due to lack of time. What's still missing is a mechanism to associate entities with ALSA controls.
The association of ALSA stuff is the biggest obstacle, IMHO. The implementation of the notification mechanism itself is trivial, no matter what way is used. But, it's pretty new that you create the association between jacks and various components (PCM, control elements, whatever). Such information is completely missing in the current driver, thus this must be added newly from scratch.
Basically this was the reason I didn't go further for the jack notification implementation with ALSA control API (besides the lack of time). Which information should be coupled and how should be -- this has to be discussed in details beforehand.
thanks,
Takashi