I am on a custom board using an i.MX6. I am using Yocto (Pyro) to build my kernel (4.14.16).
I am using the generic imx6qdl.dtsi device tree entry for PWM2 to drive the fan and it appears to work fine. The fan has a Tachometer input, which is connected to GPIO2_7. How do I read the fan speed? I have seen device tree blobs for cooling devices, but none of the examples seem to have a tachometer to monitor the fan's speed.
/sys/class/hwmon/
(and/sys/class/pwm/
)? I'm guessing yes, but just want to be sure there isn't an easy solution there. – derobert Mar 8 '19 at 20:53/sys/class/pwm/
but there was no mechanism to read back the speed (just the PWM that i had set it to). All that I have in/sys/class/hwmon
were temperature sensors. – Eskimoalva Mar 11 '19 at 12:23