Re: speedstep-centrino: ENODEV

["Sune Mølgaard" <sune@molgaard.org>]

Pallipadi, Venkatesh wrote:
>  
> 
> OK. Things seem to be fine with the BIOS. 

That sounds promising :-)

> You said it was working with 2.6.15. Do you remember whether kernel was using acpi-cpufreq or speedstep-centrino?

Sorry, I don't know, but I can build it and check.

> One change that has happened in this region is that If your BIOS supports both speedstep-centrino and acpi-cpufreq, with 2.6.15 any one of those drivers would have worked. But now with 2.6.18, acpi-cpufreq will not work in the above case and you have to use speedstep_centrino. This was done because, speedstep-centrino has more features than acpi-cpufreq and also doing this helped to elimiate issues with lot of systems with kernel trying to do multiple ACPI PDC writes when BIOS doesn't expect it to. 
> 
> In short:
> (1) If you were using acpi-cpufreq in 2.6.15, there is a high chance that it wont work with 2.6.18 and you should be able to use speedstep-centrino in its place. Make sure you have properly configured speedstep-centrino (You should select X86_SPEEDSTEP_CENTRINO_ACPI along with X86_SPEEDSTEP_CENTRINO).
> 
> (2) If you were using speedstep-centrino in 2.6.15 and now it doesn't work with 2.6.18, then we have a new regression here and we need to root cause it further by enabling cpufreq.debug and getting more debug messages to see where it is failing....
> 

Seems like 1 then. Will check the speedstep-centrino settings in the 
kernel. Thanks. I'll report back, but probably not until tomorrow.

BR,

Sune