Re: [PATCH v11] asus-wmi: Add support for custom fan curves

From: Luke Jones
Date: Tue Sep 28 2021 - 07:44:19 EST

Sure, the path is similar to /sys/devices/platform/asus-nb-wmi/hwmon/hwmon4/pwm1_enable where hwmon4 will likely be different depending on init, and pwm2_enable is the second fan if it exists. The values are 1,2,3 - where 1 = fan curve enabled/manual, 2 = auto. 3 here is custom extra that writes default curve back then defaults to 2.

As I understand it, this should be adhering to the accepted kernel standard, so if you use this for ASUS laptops, then it should carry over to other brands that implement it also.

Hope this is helpful,

On Tue, Sep 28 2021 at 13:36:57 +0200, Bastien Nocera <hadess@xxxxxxxxxx> wrote:
On Wed, 2021-09-08 at 11:22 +1200, Luke D. Jones wrote:
Add support for custom fan curves found on some ASUS ROG laptops.

These laptops have the ability to set a custom curve for the CPU
and GPU fans via two ACPI methods.

This patch adds two pwm<N> attributes to the hwmon sysfs,
pwm1 for CPU fan, pwm2 for GPU fan. Both are under the hwmon of the
name `asus_custom_fan_curve`. There is no safety check of the set
fan curves - this must be done in userspace.

The fans have settings [1,2,3] under pwm<N>_enable:
1. Enable and write settings out
2. Disable and use factory fan mode
3. Same as 2, additionally restoring default factory curve.

Use of 2 means that the curve the user has set is still stored and
won't be erased, but the laptop will be using its default auto-fan
mode. Re-enabling the manual mode then activates the curves again.

- pwm<N>_enable = 0 is an invalid setting.
- pwm is actually a percentage and is scaled on writing to device.

I was trying to update:
but I don't understand what files I need to check for what values to
detect whether custom fan curves were used.

Can you help me out here?

Also, was this patch accepted in the pdx86 tree?