Another observation:
I've uncommented  ci_fan_ctrl_set_fan_speed_percent and tried to bind it to
hwmon interface.

So, if I try to set static value to the fan, then I see 0x50CB1435 in
CG_FDO_CTRL2 and the fan runs 100% percent always, regardless of values I'm
echoing

But if I push 0x50CB0C00 to the CG_FDO_CTRL2 instead of trusting 
ci_fan_ctrl_set_static_mode, it begins to react on values I echoed.

Can you elaborate on what each bit of this control register means? Maybe I just
can't into abbreviations :)