This is a kernel driver for the Corsair Commander Pro.

Features:
Recognize connected fans, read fan speeds.
Read connected thermal sensors.
Set and read fan speed with single pwm value.
Set fan speed with target value.
Read voltage values.

If you would like to test it, clone the repository.
make && sudo insmod corsair-cpro.ko

If you run sensors, it should show up.

Features in /sys/class/hwmon/hwmon*
fan*_label shows the number and the connection status.
fan*_input shows the fan speed.
fan*_target sets target RPM values.
pwm* is takes numbers from 0-255.
temp*_input shows the temperature.
in0_label voltage on 12v rail
in1_label voltage on 5v rail
in2_label voltage on 3.3v rail

What it cannot do:
Set internal fan curves depending on temp sensors
RGB related things

Issues:
If the fan configuration is not set to auto on a channel, the driver may not detect a connected fan. Try to use https://github.com/MisterZ42/corsair-cpro-setconf to set the fans to the correct mode.

DISCLAIMER:
This is not an official Corsair product. There is no warranty. It is licensed under the GPL2.