On Wed, Dec 16, 2020 at 7:42 PM Barnabás Pőcze <pobrn@xxxxxxxxxxxxxx> wrote:
>
> 2020. december 16., szerda 19:13 keltezéssel, Rafael J. Wysocki írta:
>
> > On Fri, Dec 11, 2020 at 3:15 AM Mark Pearson <markpearson@xxxxxxxxxx> wrote:
> > >
> > > This is the initial implementation of the platform-profile feature.
> > > It provides the details discussed and outlined in the
> > > sysfs-platform_profile document.
> > >
> > > Many modern systems have the ability to modify the operating profile to
> > > control aspects like fan speed, temperature and power levels. This
> > > module provides a common sysfs interface that platform modules can register
> > > against to control their individual profile options.
> > >
> > > Signed-off-by: Mark Pearson <markpearson@xxxxxxxxxx>
> > [...]
> > > +enum platform_profile_option {
> > > + PLATFORM_PROFILE_LOW,
> > > + PLATFORM_PROFILE_COOL,
> > > + PLATFORM_PROFILE_QUIET,
> > > + PLATFORM_PROFILE_BALANCED,
> > > + PLATFORM_PROFILE_PERFORM,
> > > + PLATFORM_PROFILE_LAST, /*must always be last */
> > > +};
> > > +
> > > +struct platform_profile_handler {
> > > + unsigned long choices[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)];
> > > + int (*profile_get)(enum platform_profile_option *profile);
> >
> > I'm not sure why this callback is necessary and, provided that there
> > is a good enough reason, why it cannot return an enum
> > platform_profile_option value.
> >
> > In principle, if ->profile_set() returns 0, the requested profile can
> > be saved in a static var and then returned by subsequent "read"
> > operations.
> >
>
> It is possible that the platform profile can be changed with (e.g.) a dedicated
> button (commonly found on laptops), in which case there needs to be a mechanism
> to retrieve the new profile, which would not be possible without introducing
> something else in place of that getter - unless I'm missing something obvious.
Fair enough.
The other question remains, then.
