lexming

My board is an Helios4 rev 1.1. If only early revisions of the board are affected, that could explain why not everybody is experiencing this issue.

I have the same issue as OP. Only the fan connected to connector J17 changes speed according to PWM settings in kernel. Fan at J10 is always at full speed. On my side this has happened for a long time, at least for 6 months. So I can say that it's not related to 5.15.86-mvebu. Now I am on 5.15.80-mvebu (current linux-image-current-mvebu in bullseye). I swapped and replaced fans to verify a hardware issue on the affected fan as well, but in all cases the fan connected to J10 spins at full speed. If there is a hardware error, it must be on the connector / board. On system's side all seems fine though, setting the fan speed through `/dev/fan-j10/pwm1` works without error and the value sticks.