Is your enhancement proposal related to a problem? Please describe.
In the ISO API, the data paths are automatically setup and removed by the ISO layer at connection/disconnection.
This design offers a simpler version of ISO, but it is also less flexible, and does not allow the upper layers to control how or when the ISO data paths are setup. This design have caused several issues in BAP where multiple unicast streams may share the same CIS, but enters the streaming state at different times (unlike a CIS where both directions are connected at the same time).
ISO should not autonomously setup the ISO data path, and should be done by the upper layers
Describe the solution you'd like
Remove the call to bt_iso_setup_data_path in bt_iso_connected and the call to bt_iso_remove_data_path in bt_iso_chan_disconnected.
Move the bt_iso_setup_data_path and bt_iso_remove_data_path to public API functions that allows the upper layer to control the ISO data path. The parameters may be modified.
Finally remove the struct bt_iso_chan_path *path; from struct bt_iso_chan_io_qos.
Describe alternatives you've considered
N/A
Additional context
Samples, tests and BAP need to be modified for this as well, and thus is a larger change.
Consider implementing the data path functionality in BAP, rather than exposing similar functions at the BAP level, as the BAP implementation should be able to control the data paths (basically setup the data path when entering streaming (or even enabling) state, and remove when exiting the streamng state.
Thalley
commented
3 weeks ago
Is your enhancement proposal related to a problem? Please describe. In the ISO API, the data paths are automatically setup and removed by the ISO layer at connection/disconnection.
This design offers a simpler version of ISO, but it is also less flexible, and does not allow the upper layers to control how or when the ISO data paths are setup. This design have caused several issues in BAP where multiple unicast streams may share the same CIS, but enters the streaming state at different times (unlike a CIS where both directions are connected at the same time). ISO should not autonomously setup the ISO data path, and should be done by the upper layers
Describe the solution you'd like Remove the call to
bt_iso_setup_data_pathinbt_iso_connectedand the call tobt_iso_remove_data_pathinbt_iso_chan_disconnected.Move the
bt_iso_setup_data_pathandbt_iso_remove_data_pathto public API functions that allows the upper layer to control the ISO data path. The parameters may be modified.Finally remove the
struct bt_iso_chan_path *path;fromstruct bt_iso_chan_io_qos.Describe alternatives you've considered N/A
Additional context Samples, tests and BAP need to be modified for this as well, and thus is a larger change. Consider implementing the data path functionality in BAP, rather than exposing similar functions at the BAP level, as the BAP implementation should be able to control the data paths (basically setup the data path when entering streaming (or even enabling) state, and remove when exiting the streamng state.