[ltp] fan always on: ACPI on IBM ThinkPad R51

[graziano obertelli]

On Tue, 2004-08-31 at 08:52, susinho@ultreia.org wrote:
> Hi all. This is my first message to this list.
> 
> I recently owned an IBM Thinkpad R51 1830-BG8 (P Mobile 1.5 with ATI
> Radeon M 7500). After wiping the XP thingie, I installed a GNU/ Linux
> Debian (sarge) and all works *fine* except the cooling fan, wich is
> always on making a really anoying noise: after started at 39 C the fan
> doesn't stop, even when the machine doing nothing.
> 
> The first thing I tryed was to update the BIOS from 3.05a (the original
> one shipped with the machine) to 3.06f wich theoretycally fixes the fan
> noise problems. But the behaviour of the machine was exactly the same
> after the BIOS update. I uploaded both (buggy) IBM original DSDTs for
> reference:
> 
> http://acpi.sourceforge.net/dsdt/tables/IBM/R51_1830-BG8/IBM-R51_1830-BG8-3.05a-original.asl.gz
> http://acpi.sourceforge.net/dsdt/tables/IBM/R51_1830-BG8/IBM-R51_1830-BG8-3.06f-original.asl.gz
> 
> following the HOWTOs, I fixed the last one (I don't understand what I
> did, but at least iasl says no errors and no warnings after the fix). I
> included the hex table in the kernel, but after sucesfully loaded, the
> behaviour still remains the same one. Also I tryed this modified version
> of the 3.03 BIOS DSDT
> 
> http://acpi.sourceforge.net/dsdt/tables/IBM/R51/IBM-R51-3.03-custom.asl.gz
> 
> , but my machine reboots as critical trip points appears to be set to
> -273 C.
> 
> I did all my tests with 2.6.6, 2.6.7 and 2.6.8 debian patched kernels.
> The system manually suspends ok (to memory and disk with swsusp2).
> Cpufreq works ok, with powernowd the processor is always at the minimum
> frecuency (600000 MHz) and C3 state. Setting the throttling to 7
> doesn't changes nothing (well, the machine goes slowly, but the fan is
> still on). The only hot chip is the graphics one, now managed by the
> radeonfb driver: but it is hot anyway, even without kernel support,
> without AGP and DRI, X or text mode.
> 
> I was reading the ACPI spec in the thermal side, but modifying passive
> trip points has no effect, and active cooling mode doesn't appear to be
> available, I don't know how to activate it. Also the /proc/acpi/fan/
> directory is empty.
> 
> cat /proc/acpi/thermal_zone/THM0/trip_points (only shows THM0)
> critical (S5): 94 C
> passive: 92 C: tc1=5 tc2=4 tsp=600 devices=0xdfe2e228
> 
> cat /proc/acpi/thermal_zone/THM0/cooling_mode
> cooling mode: passive
> 
> So, does anyone of you know how can I modify the fan starting/ stopping
> points? Is it a lack of the ACPI support, or perhaps a fix to be done in
> the DSDT definition? both?
> 
> thank you.

Hi,

I have a T41 and I'm having the same problem (I think it's a pretty
common ... feature amongst thinkpad). I started to use Alex's patch to
the radeon X driver to use PowerPlay and under apm I indeed have less
fan activity. Under acpi this is not true, but the machine runs much
cooler though.

I tried to play with the trip_points myself: I think one field is
missing (active[0] or something like that). I cna change them but the
fan still goes no matter what.

graziano

-- 
+-----------------------+--------------------------+
| Graziano Obertelli    | CS Dept. Rm 102          |
| graziano@cs.ucsb.edu  | University of California |
| (805) 893-5212        | Santa Barbara, CA 93106  |
+-----------------------+--------------------------+