Re: [PATCH v14 RESEND 0/6] Merge redmi-wmi into bitland-mifs-wmi

[Hans de Goede <hansg@kernel.org>]

Hi,

On 26-Oct-26 20:56, Chris Taraszka wrote:
> On Mon, 26 Oct 2026, Hans de Goede wrote:
>> 1) This assumes the event indicates a platform-profile-change has happened, if
>> it is a request for a platform-profile-change then platform_profile_cycle();
>> should be used instead.
> 
> Hi,
> 
> Some data for this and for Mingyou's KBD_BRIGHTNESS question, from the
> Xiaomi Book Pro 14 (TM2424, BIOS XMAPT4B0P0A0A), traced with a kprobe
> on bitland_mifs_wmi_notify() with v13 on v7.3 (v14 has the same event
> handling):

Thank you for the info.
> - Fn+Space (keyboard backlight) sends no WMI event at all, neither 0x05
>   nor anything else, and does not change the backlight under Linux. So
>   this model cannot tell whether the firmware handles KBD_BRIGHTNESS.

Hmm, I wonder if this maybe sends some scan-code on the PS/2 atkbd
interface? Windows must get an event somehow ...

> - Fn+K sends event 0x28 with value_low 0x01 on every press (01 28 01 00),
>   not 0x16. The firmware does not change the mode by itself: the
>   SystemPerMode value (EC 0x68) stays the same across the presses. If
>   0x28 is the performance mode key on this model, it is a request rather
>   than a notification, so platform_profile_cycle() would fit. 0x28 is
>   currently logged as "Unknown WMI event".

Ack, this sounds like a case for calling platform_profile_cycle() if
platform-profile support is present.

> - On Windows on the same machine, with Xiaomi PC Manager not running
>   (it fails to start on this install), neither Fn+K nor Fn+Space does
>   anything either. So Fn+K looks like a request that Xiaomi's software
>   normally acts on, not a mode change made by the firmware.
> 
> - Mic mute sends 0x21 with value_low 1 and 0 and is reported as
>   KEY_MICMUTE, as expected.

Hmm, if the value-low toggles I wonder if the firmware also mutes
the mic itself ?  This may need some special handling.

Regards,

Hans