Re: [RFC PATCH 0/3] ACPI: platform_profile: Let drivers dynamically refresh choices

Hridesh MG
2025-01-07T16:33:50Z

On Tue, Jan 7, 2025 at 9:21 PM Mario Limonciello
<mario.limonciello@amd.com> wrote:
>
> On 1/7/2025 07:14, Hridesh MG wrote:
> > On Tue, Jan 7, 2025 at 7:49 AM Mark Pearson <mpearson-lenovo@squebb.ca> wrote:
> >>
> >> Hi Kurt,
> >>
> >> On Sun, Jan 5, 2025, at 11:45 PM, Kurt Borja wrote:
> >>> Hello,
> >>>
> >>> Some drivers may need to dynamically modify their selected `choices`.
> >>> Such is the case of the acer-wmi driver, which implemented their own
> >>> profile cycling method, because users expect different profiles to be
> >>> available whether the laptop is on AC or not [1].
> >>>
> >>> These series would allow acer-wmi to simplify this custom cycling method
> >>> to use platform_profile_cycle(), as it's already being proposed in these
> >>> series [2]; without changing expected behaviors, by refreshing their
> >>> selected choices on AC connect/disconnect events, which would also solve
> >>> this discussion [3].
> >>>
> >>> Additionally, I think the platform_profile_ops approach would enable us
> >>> to hide the platform_profile_handler in the future, and instead just pass
> >>> the class device to get/set methods like the HWMON subsystem does.
> >>>
> >>> I think having this kind of flexibility is valuable. Let me know what you
> >>> think!
> >>>
> >>
> >> I personally would love to see how this would be used for the acer issue highlighted to see how it would work out. It feels like the series is short a patch :)
> >
> > I do think that having this flexibility would be good, as i was
> > considering manually clearing the set bits and calling platform_notify
> > for the acer series, but in my specific case (for devices using the
> > predator v4 interface) it was found that the hardware was responsive
> > to all profiles regardless of AC/battery mode so it made sense to
> > leave this kind of artificial limiting of profiles to the
> > userspace--similar to how the Windows driver handles it through the
> > Nitro Sense app.
> >
> > I feel like users should have the power to utilize their hardware in
> > the way they want it to, though if there is a compelling reason to
> > limit the profiles then i'd be more than happy to add this to the
> > series :)
> >
> >
> > --
> > Hridesh MG
>
> I agree with Mark, this series is missing the patch that shows exactly
> how this would be used. Furthermore; what exactly are the differences
> in choices between AC or DC?
On the predator series, the Windows OEM application only allows you to
select the low-power and balanced platform profiles on DC. These
profiles can however still be activated through WMI methods and the
hardware will apply them.

> To "userspace" I fail to understand how "balanced" is different from AC
> to DC for example.
It is not, the profiles or states themselves are not modified between
AC and DC, just the switching between them is affected.

--
Thanks,
Hridesh MG