Commit in question: https://lkml.org/lkml/2018/9/27/647 Device tested on: OnePlus 5 Android Version: 9, Pie Kernel Version: 4.4.177 (Personal Kernel)
This patch seems to break Bluetooth connectivity for DualShock 4 controllers on 4.4. Reverting it fixes the issue, reported and confirmed by one of my users. I've confirmed that this happens on other devices of the same kernel version (4.4.y) - Redmi Note 5 Pro and other OnePlus 5/5T's for kernels that have this commit.