[lm-sensors] Random thoughts on fan speed control

[Rudolf Marek]

Hi,

Just quick snip because I gotta work too ;)

> * Reading the F71805F documentation, I learned that the external
> circuitery needed for PWM fan speed control is completely different
> from the one needed for DC fan speed control. So I wonder if it is a
> good idea to let the user change between the two modes. Clearly the
> BIOS should set it right. I tried to switch to DC mode and it had no
> effect at all on my fan (not even on/off). I wonder if it is possible
> to confuse or even damage the hardware by using the wrong mode?

Yes DC/PWM settings were already removed from W83793 and imho not implemented on 
EHF too.

You need to know what circuits are onboard -> BIOS should do that for you. If 
you want to implement this I would suggest just a kernel param for BIOS fixups.

Rudolf