On 1/7/2025 07:14, Hridesh MG wrote:
On Tue, Jan 7, 2025 at 7:49 AM Mark Pearson <mpearson-lenovo@xxxxxxxxx> 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?
To "userspace" I fail to understand how "balanced" is different from AC
to DC for example.
If an implementation has differences for AC vs DC would it make more
sense to have that abstraction in the "profile handlers" instead of the ops?
IE always have "low-power, balanced, performance" for choices. If the
system is on AC the profile handler might do something different than on
DC for a given state.
Another idea I had while thinking about this is that the platform
profile core can have a sysfs file to indicate whether or not to "allow"
power state sensitive values.
It could default to "1" and then it can send AC/DC events to the
platform profile handlers when enabled. If userspace prefers not to use
it, then they can set it to 0 and then the profile handler would stop
reacting.
