Contribute
Register

[Guide] Laptop backlight control using AppleBacklightFixup.kext

SSDT-PNLF.aml - _UID is set depending on PWMMax...
Mine is COMMET LAKE i3-10110u DELL - any given options of UID - screen is very dimmed
What is the settengs for me ?
 
For my Asus G750-JX it has an nvidia GTX 770M, natively supported while IGPU is disabled by Asus in Bios. Whatevergreen does not support laptop Nvidia only IGPU in Laptops so LCD brightness cannot function with just WTG. I still need to use applebacklightfixup along with a properly made SSDT-Nvidia.aml and WTG to prevent black screen. With those 3 files I have fully working LCD brightness and apple animation on Catalina 10.15.4

I also have an older laptop Dell M1530 core 2 duo with older GFX GT 8600, but very famous for making its way all the way through most MacOS upgrades up to 10.11 and with some legacy graphics patching to work in Catalina but trying to get brightness to work with the same combination of an SSDT, WTG and ABF is more challenging in this particular case.
 
Last edited:
Hi @RehabMan pls when I follow the guide is not working on my computer I don't know why
 
Hiya, I have some trouble while using the latest Lilu + Whatevergreen + AddPNLF in Clover. The maximum brightness is very low (say 50% or less of what it should be). The slider does work, but only to darker.

When I use the PNLF.ssdt instead of AddPFNL in Clover, there is no brightness slider. When I use IntelBacklightFixup.kext (with or without PNLF.ssdt) separately it doesn't work either. I now assume IBF.kext is ncluded in Whatevergreen anyway.

I tried in Clover:
- enable_cfl_backlight_fix (boot-arg)
- Graphics/InjectEDID + ProductID: 9c7c
- SetIntelBacklight + SetIntelMaxBacklight (no value, not needed according to Whatevergreen Wiki)

I tried looking into using SSDT-RMCF but honestly I don't know where to go with it.

Hopefully you can help me find a fix!
Have you ever managed to solve this?
 
I had the same issue, I solved it with a kind of hybrid approach, using WEG and backlight smoother kext together. See my EFI at https://github.com/joske/DELL-XPS-13-9370.
Cool! I checked your EFI but I don't see igfxpwmmax=0x???? bootarg in your config. Did the kext itself fixed the dim maximum brightness? I'm using the Intel Hd 4000 (ivy bridge) by the way.
 
No, I don't know why how it works, but this is the only way it works. WEG alone does not work at all. Disabling the WEG backlight code and using smoother kext leads to the problem with the max brightness too low. By accident I did this and it worked.

edit: be sure to also use the PNLF aml file from my EFI.
Thanks! Now I have full brightness.

The only problem is that the slider reaches the maximum brightness at the middle. So the brightness slider doesn't increase anything after is passes through the half of it's lenght, it already reaches max at the middle.
 
Last edited:
I have question for my laptop please, How can i use hot key Fn+F8 Fn+F9 to control brightness level?
post 1 has a link
 
Back
Top