Jonathan Dowland wrote: > On Sun Apr 13, 2025 at 10:23 PM BST, Eben King wrote: > > sudo modprobe it87 force_id=0x8728 > > > > then running "sensors" shows > > it8728-isa-0a40 > > Adapter: ISA adapter > > <9 voltages> > > <5 fans, one of which is 0 RPM> > > <3 temps> > > intrusion0: ALARM > > > > It's been put into /etc/modules. > > That might be the way forward. In my case, the controller is managed by the > driver "nct6775". I have (the not-very-discoverable) sysfs location > /sys/devices/platform/nct6775.656/hwmon/hwmon2 containing files to control > things; e.g. writing 1 to ./pwmN_enable (N ∈ 1-7) sets fan "manual control > mode", after which I can write the values 0-255 to ./pwmN to control the > RPM. (I haven't got my fans to do quite what I want, yet, but that's not the > driver's fault.) > > nct6775 is documented reasonably well > <https://www.kernel.org/doc/html/latest/hwmon/nct6775.html>, your > controller's docs aren't quite so clear but there's some mention of writing > to pwnN_enable: <https://docs.kernel.org/hwmon/it87.html>
There's a fancontrol package which requires lm-sensors to have found the controls. This package contains a daemon that calculates fan speeds from temperatures and sets the corresponding PWM outputs to the computed values. This is useful when this feature is not provided by the BIOS or ACPI, which should normally be the case on a laptop. -dsr-
