Adjusting keyboard brightness on VOXEL causes system freeze


USB4 hang on TGL+ is a known bug that we have a workaround for, listed in our documentation. I haven’t had time to fix it properly in the kernel.

Hang/crash happens because EC doesn’t receive a response and to get that response, we need to load driver for Intel’s PMC MUXer (Power Management Controller) before USB-C driver for ChromeOS Embedded Controller.

I’m fairly certain if you unload cros-ec-typec and typec modules, then modprobe -v typec intel-pmc-mux cros-ec-typec it will work just fine.

I have no idea why that module doesn’t load before CrosEC, as we do have ACPI device that it binds to - just not the correct order. Adjusting modprobe configs or even DEPMOD in kernel modules did not help.