Comment 441 for bug 1776563

I forgot to add that some distributions may include i2c-amd-mp2 built in to the kernel and that may be an older non working version.
If that's the case then you need to rebuild the kernel without the patched i2c-amd-mp2 support and then you can add i2c-amd-mp2 as i posted in previous post.
I compiled an non patched vanilla kernel with a custom .conf and then added i2c-amd-mp2 support.
It do work with an non patched vanilla kernel, some distributions patches the kernel so much that i may be the reason that things doesn't work.