linux-kernel - Re: [PATCH 2/2] platform/x86: asus-wmi: Fix inconsistent use of thermal policies

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Message-ID: <ZxzIMsffFj2lvScb@laptop>
Date: Sat, 26 Oct 2024 11:45:06 +0100
From: Mohamed Ghanmi <mohamed.ghanmi@...com.tn>
To: Armin Wolf <W_Armin@....de>
Cc: corentin.chary@...il.com, luke@...nes.dev,
	srinivas.pandruvada@...ux.intel.com, hdegoede@...hat.com,
	ilpo.jarvinen@...ux.intel.com, Michael@...ronix.com,
	casey.g.bowman@...el.com, platform-driver-x86@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] platform/x86: asus-wmi: Fix inconsistent use of
 thermal policies

On Fri, Oct 25, 2024 at 09:15:14PM +0200, Armin Wolf wrote:
> When changing the thermal policy using the platform profile API,
> a Vivobook thermal policy is stored in throttle_thermal_policy_mode.
> 
> However everywhere else a normal thermal policy is stored inside this
> variable, potentially confusing the platform profile.
> 
> Fix this by always storing normal thermal policy values inside
> throttle_thermal_policy_mode and only do the conversion when writing
> the thermal policy to hardware.
> 
> Fixes: bcbfcebda2cb ("platform/x86: asus-wmi: add support for vivobook fan profiles")
> Signed-off-by: Armin Wolf <W_Armin@....de>
> ---
>  drivers/platform/x86/asus-wmi.c | 64 +++++++++++----------------------
>  1 file changed, 21 insertions(+), 43 deletions(-)

the original patch that i submitted did actually have the remapping
of the different fan profiles in the throttle_thermal_policy_write() methods 
because it was the cleaner solution [1]. however after having a discussion with luke, 
he shared that he might be planning to remove the throttle_thermal_policy sysfs interface 
in favour of platform_profiles [2] because of a refactoring he had been working on.

currently to control fan profiles through this driver you could use
either /sys/devices/platform/asus-nb-wmi/throttle_thermal_policy
(redundant and might get removed in the future) or through platform profiles which is the
better way of doing things.

for the reasons mentionned above, I decided to keep
throttle_therma_policy_write() unchanged and to move the remapping logic
to the asus_wmi_platform_profile_set(). this adopts the approach of
having a logical mapping stored in asus_wmi struct that has to be
converted to a physical mapping whenever needed [3].

so, if luke thinks that this won't cause any merge conflicts with his
work [4] then i see no problem with this approach even though it might cause an
order change when calling throttle_thermal_policy_switch_next()

Best Regards,
Mohamed G.

Link: https://lore.kernel.org/platform-driver-x86/20240421194320.48258-2-mohamed.ghanmi@supcom.tn/ # [1]
Link: https://lore.kernel.org/platform-driver-x86/4de768c5-aae5-4fda-a139-a8b73c8495a1@app.fastmail.com/ # [2]
Link: https://lore.kernel.org/platform-driver-x86/ZnlEuiP4Dgqpf51C@laptop/ # [3]
Link: https://lore.kernel.org/platform-driver-x86/20240930000046.51388-1-luke@ljones.dev/ # [4]