ARM – Kernel 3.19 for Odroid U3 – With Fan Control..

Updated the Odroid U3 to (patched) Kernel 3.19, from https://github.com/tobiasjakobi/linux-odroid/tree/odroid-3.19.y

Thanks to work by tobiasjakobi, this now includes the preliminary patches – updated for 3.19 – for fan control on the Odroid U3, originally posted by Lukasz Majewski at http://www.spinics.net/lists/linux-samsung-soc/msg42259.html

So, (on a Fedora 21 system) you can now control the fan, as follows:

# echo "0" >/sys/class/hwmon/hwmon0/pwm1

– fan stops (as at boot..)

# echo "65" >/sys/class/hwmon/hwmon0/pwm1

– fan runs – at reasonable speed

# echo "255" >/sys/class/hwmon/hwmon0/pwm1

– fan runs – full speed..

Temperature can be found at

# cat /sys/devices/virtual/thermal/thermal_zone0/temp

– which returns value (with fan running) of – typically – 32000  (presumably need to divide by 1000 to get ‘degrees’ Centigrade ?)

You can check this by stopping the fan, and seeing the ‘temperature’ result increasing, and then decreasing again, when the fan is restarted..

There is some old code (license uncertain?) for automated fan/temperature control from mrdjr at hardkernel, at https://github.com/mdrjr/odroidu2-fan-service.git..   This is for an older kernel version, and (presumably) Ubuntu/Debian-centric, but it may be possible to modify and update this…

As usual, more research is needed!

Robert Gadsdon.  February 10, 2015.

 


Comments

ARM – Kernel 3.19 for Odroid U3 – With Fan Control.. — 5 Comments

  1. The userspace fan-service stuff however should be no longer needed, since thermal management of the fan was added in this series (see bindings in patch 5/8).

  2. Hi! I see you’re running Fedora 21 on an Odroid U3. I’d like to do the same. I have searched for hours on the net, but I can’t find a one page Howto on how to take a stock U3 and get Fedora 21 working on it. Any suggestions? Thanks.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.