Add configuration options for the BAP/PACS sink and source endpoint
location (= channel positions) and context settings.
Although BlueZ associates these with individual endpoints, in the PACS
spec they are actually device-global, so configure directly in monitor
settings.
Currently, the PipeWire daemon registers BlueZ LE Media Endpoints
with audio capabilities covering all settings defined in the BAP spec.
However, some scenarios might require the capabilities to be restricted
to specific configurations.
This adds a method to read LC3 codec specific capabilities from the
Wireplumber config file, and provide those settings when registering
Media Endpoint objects with BlueZ. If the values are not present in
the config file, all settings will be used by default.
Below is an example of how to set the LC3 capabilities in the config
file, to support the 16_2 setting from the BAP spec:
bluez5.bap-server-capabilities.rates = [16000]
bluez5.bap-server-capabilities.durations = [10]
bluez5.bap-server-capabilities.channels = [1, 2]
bluez5.bap-server-capabilities.framelen_min = 40
bluez5.bap-server-capabilities.framelen_max = 40
bluez5.bap-server-capabilities.max_frames = 2
For multi-ASE configurations, BlueZ does the channel allocation itself,
and passes us the result in the ChannelAllocation parameter.
If it is present, don't do the allocation ourselves but use that value
instead.
BlueZ now requires endpoints to set Locations/Context, so set them to
some sensible default values. These could in principle be made
configurable later.
If BAP codec configuration is mono channel with unspecified location,
set the channel position from transport location.
This in principle should be set in SelectProperties, but currently BlueZ
doesn't tell us that yet there, so we hack it up later on.
The number of channels is determined by Audio_Channel_Allocation.
One frame block contains all channels. (BAP v1.0.1 Sec. 4.2)
Fix the handling of frame blocks and counting of numbers of channels. We
support and configure only one frame block per packet.
Consider omitted Audio_Channel_Allocation to indicate MONO stream (see
BAP v1.0.1 Sec 4.3.2).
The codec may need to take into account endpoint preferred QoS values,
so parse this information and pass it to the codec's get_qos.
All the QoS struct values need to be set, as otherwise BlueZ may pass
uninitialized zero values over the air, which devices can reject. This
does not apply to CIG/CIS ids, which are automatically allocated by
default.
Fixes connecting to nrf5340 devkit, which requires a valid TargetLatency
value.
