[Feature Request] LE Audio Support

[zxzxwu]

As https://github.com/google/bumble/pull/308 has been a little bit big, so I am going to list some roadmap here.

Scope

The initial implementation will focus on the Unicast Server role defined in Basic Audio Profile 2.1.1 due to its relative ease of implementation and critical role in testing. This initial phase will be limited to single-device (BR/EDR TWS-like) use cases. Following the successful completion of the single-instance implementation, we may expand the scope to include multi-instance support.

Unicast Client and Broadcast roles are not in the scope.

Roadmap

There might be some PRs:

• [x] General
  • [x] LE Audio GATT definitions(BAP, MCP, CCP, CAP, CSIP, MICP, VCP)
  • https://github.com/google/bumble/pull/343
  • [x] CIS HCI packet definititions
  • https://github.com/google/bumble/pull/333
• [x] CSIP/CAP
  • [x] CSIS - Characteristics with plaintext SIRK
  • https://github.com/google/bumble/pull/350
  • [x] CAS
  • [x] [Optional] CSIS - RSI generation
  • [x] [Optional] CSIS - Encrypted SIRK
• [x] HCI / Host
  • [x] CIS integration
  • https://github.com/google/bumble/pull/344
• [x] BAP
  • [x] PACS support
  • https://github.com/google/bumble/pull/356
  • [x] ASCS & Sink ASE
  • https://github.com/google/bumble/pull/359
  • [x] Source ASE
  • [x] LC3 codec integration(coop with liblc3)
• [ ] [Optional] EATT(Enhanced ATT)

By the end of 2023, I think at least General, CAP and CSIP are not too difficult to complete.

BAP might have some progress in the December, but CIS integration will take a longer time. If there cannot be an overall solution, at least we can provide an example Unicast server built on a naive structure.

[zxzxwu]

https://github.com/google/bumble/pull/343 for [1]

[barbibulle]

Great plan. I'm all for splitting the effort into incremental (and/or parallel) steps. As long as we make it clear that the entire LE audio support will be in flux for a while, and highly experimental (the APIs defined along the way are likely to change as we build this up).

[zxzxwu]

It seems like CSIP/CAP might not be necessary when only single device is present?