Bug 21922

Summary: Request for user Fan control feature -- Lenovo IdeaPad G555
Product: Drivers Reporter: sc.snoopcatt
Component: Platform_x86Assignee: drivers_platform_x86 (drivers_platform_x86)
Severity: normal CC: acpi-bugzilla, alan, lenb, rui.zhang
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.36 Subsystem:
Regression: No Bisected commit-id:
Bug Depends on:    
Bug Blocks: 56331    

Description sc.snoopcatt 2010-11-03 17:42:07 UTC
How can I control fans speed on my laptop - Lenovo IdeaPad G555?
$ acpi -c
shows 3 cooling devices: 
1) LCD Brightness
2) Throttling
3) unknown
first two controls works: 1st change brightness, 2nd change throttling.
last "cooling devices" doesn't work. 
but.. how can I change fan speed?
Comment 1 Zhang Rui 2010-11-04 02:20:52 UTC
(In reply to comment #0)
> How can I control fans speed on my laptop - Lenovo IdeaPad G555?

This depends on which kind of fan device do you have on this laptop.

Fan can be controlled in different ways, e.g.
1. ACPI. (the generic way)
2. platform driver/native driver (need platform specific code)
3. BIOS (transparent to OS)

please attach the acpidump output of your laptop so that I can check if there is ACPI fan device or not. Although according to the output of "acpi -c", the answer is probably "no".
Comment 2 Len Brown 2010-11-09 02:27:05 UTC
As ACPI does not have a feature where a user can control fans speed
on their laptop, moving this to platform drivers.  (we can observe
what the BIOS does for your, but that is about it)  It is conceivable
that thinkpad-acpi driver may have a native feature here and may
run on this box, so moving this bug to the drivers/platform category.