[gentoo-user] Problem with fan control on laptop

[Peiding CHEN]

Hello,

I've suffered from the problem with cpu fan control on my laptop for a long time. I hope someone could help me get rid of it.

Here is the problem:

My laptop is "Toshiba Portégé M901". I installed Gentoo with xfce4 as the desktop environment and compiled the kernel manually. After system booting, the fan will either doesn't spin at all or spins only at one speed level and the speed will never change. The automatic control is only activated when the cpu temperature drops and passes the trip point (doesn't start while temperature increase). But I can control the speed manually. So my temporary solution is to start the fan manually in high speed when I run some heavy applications for getting a high cpu temperature(more than 70°C). Then when the temperature drops and passes the trip point, the automatic control is activated. The fan could be modulated according to the cpu temperature as what it should be.

The way to activate the fan manually

grep . /sys/class/thermal/*/*
echo 0 > /sys/class/thermal/cooling_device4/cur_state
echo 0 > /sys/class/thermal/cooling_device5/cur_state

I think it's weird to start the fan by "echo 0" since it commonly means stopping the fan. I should do "echo 0" first to make the fan work at certain speed(running "echo 1 > " at the first doesn't work).
Then all commands seem to work correctly as "echo 0" for stopping and "echo 1" for start.

PS: in my laptop:
/sys/class/thermal/cooling_device0/type:LCD
/sys/class/thermal/cooling_device1/type:Processor
/sys/class/thermal/cooling_device2/type:Processor
/sys/class/thermal/cooling_device3/type:Fan
/sys/class/thermal/cooling_device4/type:Fan
/sys/class/thermal/cooling_device5/type:Fan
/sys/class/thermal/cooling_device6/type:Fan
/sys/class/thermal/cooling_device7/type:Fan
/sys/class/thermal/cooling_device8/type:Fan


The output of dmesg suggest that all fans are on.
[ 7.015190] ACPI: Fan [FAN0] (on)
[ 7.015235] ACPI: Fan [FAN1] (on)
[ 7.015279] ACPI: Fan [FAN2] (on)
[ 7.015322] ACPI: Fan [FAN3] (on)
[ 7.015366] ACPI: Fan [FAN4] (on)
[ 7.015410] ACPI: Fan [FAN5] (on)

In addition, xfce4 power-management nor lm_sensors could recognize my fan. Recompiling the kernel by genkernel as "genkernel all" didn't solved the problem.

Solution expected:
So my fan could work, but the fan couldn't be modulated by itself. I want the automatic control could be activated just after booting. (My temporary solution need CPU work in high temperature, so this doesn't work when I boot up my laptop from the cold).

What do you think should I do to? Do you have some ideas?

Thanks a lot

Regards

--

Peiding CHEN
Etudiant, Spécialité - Energétique et Environnement
Université Pierre et Marie CURIE
Paris
France