Re: [PATCH] Add keycode to Dell G-Mode key

[Marcos Alano <marcoshalano@gmail.com>]

On 19/04/2025 08:31, Marcos Alano wrote:
> This key exists in some Alienware and Dell machines.
> On Windows it activates the performance mode.
> 
I noticed just now the missing of a rationale about my patch. Sorry 
about that.

This patch is part of a multiple stage plans to enable the G-Mode key on 
Linux.
The most important part is this patch, that will define an exclusive key 
code for the key.
There will be necessary a newer version for libevdev, specially the 
Python support, using the newer headers with the key code I'm adding in 
there.
Subsequently, I will update my change in systemd so the scan code for 
this key, 0x68, returns `KEY_GMODE` (today is returning a very generic 
key code).
Finally, I will release a simple Python code I developed that is 
responsible for monitoring event devices, /dev/input/event* (since I 
doubt that I have how to know what is the keyboard device).
When detect `KEY_GMODE` it will enable performance mode, and when press 
again, it will disable.
Today I'm using D-Bus to call power-profiles-daemon, but the idea in the 
future, with a quite set in stone key code, any user-space tool, like 
power-profiles-daemon, can use and manage the key by themselves.

Please let me know about any doubts or considerations.


> Signed-off-by: Marcos Alano <marcoshalano@gmail.com>
> ---
>   include/uapi/linux/input-event-codes.h | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/include/uapi/linux/input-event-codes.h b/include/uapi/linux/input-event-codes.h
> index 5a199f3d4a26..85c6a612ee84 100644
> --- a/include/uapi/linux/input-event-codes.h
> +++ b/include/uapi/linux/input-event-codes.h
> @@ -765,6 +765,9 @@
>   #define KEY_KBD_LCD_MENU4		0x2bb
>   #define KEY_KBD_LCD_MENU5		0x2bc
>   
> +/* G-Mode key present in some Alienware and Dell machines */
> +#define KEY_GMODE			0x2bd
> +
>   #define BTN_TRIGGER_HAPPY		0x2c0
>   #define BTN_TRIGGER_HAPPY1		0x2c0
>   #define BTN_TRIGGER_HAPPY2		0x2c1

-- 
Marcos Alano