Re: community PM requirements/issues and PowerOP [Was: Re: So, what's the status on the recent patches here?]

Eugeny S. Mints
2006-09-14T12:35:26Z

Vitaly,

Vitaly Wool wrote:
> Eugeny,
>
> On 9/14/06, Eugeny S. Mints <eugeny.mints@gmail.com> wrote:
>
>> Separate or one universal user space<->kernel interface is another story.
>> Universal is preferred of course and in two words to achieve universal
>> interface
>> current cpufreq interface needs to be improved - but remains unchanged
>> for user
>> space !!!! - in the way to handle "chose closet predefined frequency
>> to an
>> arbitrary freq value echo'ed into /sys/cpufreq/cpuN/freq"
>> functionality in user
>> space instead of in the kernel. Assuming that frequency attribute is
>> exported
>> for all available operating points it is possible to implement the
>> "cpufreq
>> frequency selection logic" in user space and having such functionality
>> in the
>> kernel just violates the main rule of having everything possible
>> outside of the
>> kernel.
>
> Let's not be in a hurry, if possible.
> I wonder why not to present PowerOP with a _separate_ *kernel* API at
> the moment.
it is exactly how PowerOP submission is positioned - it was submitted as a
standalone patch without any relationship to cpufreq integration patch.

Cpufreq patch was submitted mostly for reference and discussion; to demonstrate
that future integration with cpufreq is in mind and outline that PowerOP will
not require cpufreq _interface_ to be changed.
>
>> More details here:
>> http://lists.osdl.org/pipermail/linux-pm/2006-September/003660.html
>> and here
>> http://lists.osdl.org/pipermail/linux-pm/2006-September/003671.html
>
> Again, let's first make PowerOP accepted in mainline and then start
> talking about integration with cpufreq.

that's exactly our understanding of an evolutionary development process.

> Looking again at the links you've provided, I'd guess BTW that you
> meant configfs not sysfs in some cases.
configfs is in my TODO list.

Eugeny
>
> Vitaly
>