Re: [PATCH v5 2/5] hwmon: (max31790) Fix and split pwm*_enable
From: Jan Kundrát
Date: Wed May 19 2021 - 05:20:14 EST
As it turns out, even the current code doesn't really work for fans 7..12.
sr = get_tach_period(data->fan_dynamics[channel]);
However, the data->fan_dynamics array has only 6 entries, not 12, so
reading fan[7-12]_input will result in bad/random values.
Hi Guenter, I'm Vaclav's colleague. The chip can indeed reconfigure each
PWMOUT pin either as a PWM output or as a TACH input, but that's not
something that's correctly implemented in the current code, and we have no
use for that either (and we cannot test that on our PCBs easily, we do not
have the manufacturer's eval kit).
It looks to me that the original bug is that the current docs mention 12
fan inputs. Would you be OK with a patch series which fixes the docs so
that the chip always exports 6 TACH inputs and 6 PWMOUT channels?
Cheers,
Jan