Titan 18HX 2024-08 build keyboard backlight not working

[sempervictus]

Laptop model

Titan 18HX

EC firmware version

its actually 1822EMS1.116 but reads as 1822EMS1.114 (see last PR comment)

Description

My 14th gen CPU went south, as so many do, and i had to acquire a replacement machine due to their impossible RMA policy and active refusal to honor right to repair laws (as so many vendors do). Original system was mfg date of 2023-12, new one is 2024-08. It seems that something was changed on the motherboard because the fn+f8 key does change /sys/devices/platform/msi-ec/leds/msiacpi::kbd_backlight/brightness but the keyboard does not light up. Moving the new motherboard to the original chassis w/ the original keyboard does not help - same deal: pressing the fn key, the f keys and arrow keys for fan buttons light up but the keyboard itself does not change brightness despite increments showing in

# cat '/sys/devices/platform/msi-ec/leds/msiacpi::kbd_backlight/brightness'
3

The other oddity i'm noticing is in the way the right ctrl key now requires the fn key to be held to be recognized... seems they've changed some stuff around without changing the model designation.

This is 6.6.59, module built into the kernel tree - git log says MSI: EC from git @ 94c2a45c with v116 update.

[glpnk]

Is your keyboard RGB or just single color? Maybe they used new keyboard backlight controller

[glpnk]

Because I've seen on some RGB laptops that keyboard brightness key just changes mode. Yes, this changes value in EC, but MSI app use only key press event, generated by EC to switch brightness in app

[sempervictus]

The various marketing pictures of these show multi-color lights but in linux i've only ever had the keyboard glow red. I just need a backlight working really but whatever they did when they introduced the windows AI key seems to have changed something in that regard. There's no change in the model designation but they at least changed the right ctrl key mapping to now be the "AI key" and possibly more...

Also not sure what app we're talking about.

[glpnk]

Check maybe BIOS have control-AI remap button.

About app - I mean Windows MSI app and services is uses for processing keyboard brightness key events

[glpnk]

What about fn lock? Does it change control-AI button behavior

[sempervictus]

The BIOS is the same one as in the prior machine - haven't seen any new options in the basic menu nor noticed them in the advanced one. FN-lock does not make it a ctrl key: have to hold the actual fn key although other lock functions work. If they broke backlight to introduce a windowsai key where none existed, that would be impressively bad QA. :)