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Submitted by amrprznu on Sun, 03/08/2015 - 18:53

Fan always running after suspend

If your fan seems to be running at full throttle after suspending the computer, this could help:

  1. Create a file called 99_fan with these contents
    #!/bin/sh
# fan spindown controller script
# /etc/pm/sleep.d/99_fan
#
# https://bugzilla.redhat.com/show_bug.cgi?id=895276
# @see https://bugzilla.redhat.com/show_bug.cgi?id=895276#c18

# Save value of screen brightness
# http://sdbillin.com/ubuntu-laptop-fan-speed-revisited/
value=`cat /sys/class/backlight/acpi_video0/brightness`
case "$1" in
    hibernate|suspend)
	;;
    thaw|resume)
	sleep 5;
	# Turn the fans back to normal
	for x in /sys/class/thermal/cooling_device*/cur_state; do
	    echo 0 > $x;
	done;
	# Restore value of screen brightness
	echo "$value" >/sys/class/backlight/acpi_video0/brightness;
	;;
    *) exit $NA
	;;
esac
  2. Create another file called fan_ctrl with these contents:
    #!/bin/bash
# # To get the temperature of the cores (°C):
# # https://lkml.org/lkml/2012/12/4/428
# for i in /sys/devices/virtual/thermal/thermal_zone*/temp; do
#    echo $(( $(cat "$i") / 1000 ));
# done
# # To check that it's right:
# sensors
# # To deactivate the fans upon start:
# # https://bugzilla.redhat.com/show_bug.cgi?id=895276
#
for x in /sys/class/thermal/cooling_device*/cur_state; do
    sudo sh -c "echo 0 > $x";
done;
  3. Make the file executable (check the <path> where you saved the files, open a terminal and type cd <path>. You can also just right click on the file, go to properties and tick the box to make it executable) :
    chmod +x fan_ctrl 99_fan
  4. Copy 99_fan to /etc/pm/sleep.d/ (requires administrator privileges):
    sudo mv 99_fan /etc/pm/sleep.d/

You can run fan_ctrl whenever you need to turn off the fan manually. The other script (99_fan) will run automatically as superuser.

Revisions

03/08/2015 - 18:53
amrprznu
amrprznu