I know this is an old thread, but just adding some info:
There is a change in the 3.19 BIOS for 11th gen laptops:
Since I have a weird obsession with ACPI mutexes I took a look at this. BIOS 3.17 had no locking around ACPI → EC access for UCSI, which is bad.
BIOS 3.19 introduces two new mutexes called “UBSY” and “UBS0”. This doesn’t look like a good fix. It would be better to lock the existing mutex “ECMT”.
I tried fixing this on my machine by creating a new AML file in the initramfs, which overrides the BIOS AML. I think it behaved a bit better but it still doesn’t want to change source/sink for my Anker power thingy.
[edit: I also fixed the “version missing” problem in my replacement AML]
I can put some example code on github if anyone is interested.