the same problem. We, who made the MeeGo policy framework, concluded
that we need to either upstream our stuff or use/adopt the work that
is in progress. For the latter the best candidate seems to be the
device-manager module integrated to an UCM aware alsa module.
The policy decision point would send profile changes for the detected
cards (needed to route between BT A2DP and SCO for instance) as well
as it would send for each media role a priorized UCM device target
list. This list in turn would be used by the device manager to route
the streams (i.e. sink-inputs and source-outputs) to the right
sink/source.
Media roles would have priorities and the highest priority role would
determine the UCM verb. Currently only two seem to make sense: "HiFi"
and "Voice". UCM devices would be enabled/disabled based on the
targets for media roles. The rule would be that highest priority
device would be set first followed by lower priority devices if that
were possible at all.
So the idea is to use a modified device manager, David's jack
detection (with the port support for cards) and a stripped version of
Margarita's UCM patches.
First glance todo list for the components:
- Device Manager:
* should accept routing targets for media roles in terms of UCM devices
(e.g. 'speaker' instead of sinkname)
* maintain a map for UCM device -> card, sink, port.
* not only route the streams to the sinks but also set the ports.
* hook-in to the jack-detection callbacks
- UCM Patches:
* beside profiles ports should also be supported.
* for jack detection we would use David's work
Challenges:
- A resonable mapping of profiles and ports to UCM verbs+devices+modifiers.
- Multiple accessories of same kind (e.g. simultaneous use of multiple
BT devices, like car-kit and headset)
since we have just one 'bluetooth' UCM device
- route to multiple devices (e.g. ringtone to headset and speaker at
the same time) since only one port can
be active at the time. We could have ports for the combinations of
devices but it is kind'a ugly.
- ...
There is a lot more to say but I did not want to start with a
kilometer long mail :)
Comments, ideas, doubts etc would be highly appreciated.
br
-janos-
