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[Guide] Laptop backlight control using AppleBacklightFixup.kext

Feartech

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Thanks for your perseverance on this one Rehabman!

Had the same issue of dark screen on max but with your new updated files, all is working as it should

thanks again! :)
 

RehabMan

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I have update the files, now there is slider in display. But can not change brightness when slide it.

It is likely your computer does not use the Intel IGPU PWM for backlight control.
Maybe you already know that from previous versions of macOS/OS X?

In previous versions, you could have used ACPIBacklight.kext with "Brightness Fix" or a custom PNLF implementation, but that is not (currently) and option for you.
 

RehabMan

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Thanks for your perseverance on this one Rehabman!

Had the same issue of dark screen on max but with your new updated files, all is working as it should

thanks again! :)

Thanks for testing... and providing (positive) feedback.
In early goings, positive feedback is as important as negative...
 
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It is likely your computer does not use the Intel IGPU PWM for backlight control.
Maybe you already know that from previous versions of macOS/OS X?

In previous versions, you could have used ACPIBacklight.kext with "Brightness Fix" or a custom PNLF implementation, but that is not (currently) and option for you.

yes, now I have used ACPIBacklight.kext with "Brightness Fix" in El Capitan. I test Sierra to see whether everything is ok, so that I can update to the newest version.
You means that my laptop can not be used this fix temporarily?
 

RehabMan

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yes, now I have used ACPIBacklight.kext with "Brightness Fix" in El Capitan. I test Sierra to see whether everything is ok, so that I can update to the newest version.
You means that my laptop can not be used this fix temporarily?

Only laptops that use the IGPU PWM for backlight control can use this method.
 
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On a new setup, you will always have to boot first to load AppleBacklight.kext, then rebuild cache, then reboot. It is an artifact of Clover kext patching (cannot patch kexts that load outside of cache).

Read post #1, "Problem Reporting".

i have tried multiple times. follwed directions exactly. i see the KernelCache ID changes from new setup without backlight support to the one with injection/ssdt-pnlf/kext-patch. still no backlight profile matching for xxxx. ioreg just shows all injector profiles.

maybe the kext doesn't match the display xxxx, maybe just the last 2 xx because there are not 2 id's on the same _uid. for example my pnl with injector is _uid 15 0534 there is a034 but its _uid is 16.
 
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RehabMan

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i have tried multiple times. follwed directions exactly. i see the KernelCache ID changes from new setup without backlight support to the one with injection/ssdt-pnlf/kext-patch. still no backlight profile matching for xxxx. ioreg just shows all injector profiles.

No "Problem Reporting" files attached.
 
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No "Problem Reporting" files attached.

i have done that some many times already....let me guess the answer... clover can only patch kext in kernelcache. it's not !@#$% loading AppleBacklight into kernelcache. i am running other injectors with no issues
 

RehabMan

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i have done that some many times already....let me guess the answer... clover can only patch kext in kernelcache. it's not !@#$% loading AppleBacklight into kernelcache. i am running other injectors with no issues

You have not done it since the files were updated a few days ago.
So... to my knowledge you have not followed the guide with current content...
 
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You have not done it since the files were updated a few days ago.
So... to my knowledge you have not followed the guide with current content...

i was digging and it is how EDID is applied. the value is already set to 0x0534 for IOGraphics. changing AppleBacklight %04x to xxxx won't match IOGraphics. changing AppleBacklight %04x to 0534 wouldn't work because the injector expects xxxx. so in my specific case the injector must use 0534 in the active profile and no patch.
 
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