The bug was bisected to:
commit 0a1c7959acd9674a0e4e59f911f3e5fbf25fd693 Author: Wolfram Sang wsa@the-dreams.de Date: Wed May 17 15:22:18 2017 +0000
gpu: drm: tc35876x: move header file out of I2C realm
Bisect seems to have gone off the rails. No idea where or why.
Yes, luckily it was obvious here, saving us from chasing ghosts.