Since writing a few weeks ago about the slow pace recently for BUS1, I heard more information from one of the developers and there has also been some new activity in their Git tree.
BUS1 developer Tom Gundersen wrote in an email to Phoronix earlier this month about the BUS1 efforts. Since their "request for comments" earlier this year and presenting at the Linux Plumbers Conference, they've had generally positive feedback. For items that did come up, they are currently working to address them prior to the next round of the RFC. So things are moving forward, but BUS1 suddenly won't be proposed overnight for inclusion into the mainline kernel.
Then as you can see via their GitHub, they are back to pushing work for this module providing IPC support for the Linux kernel. Some of the recent work includes some documentation updates, build system changes, and more.
Hopefully we'll be seeing good things out of BUS1 in 2017.