Comment 132 for bug 971061

The keyboard backlight issue is separate from this issue, and is not a hardware problem.

Rather, that the linux devs decided to disable the samsung-laptop.c module in the kernel when you boot with UEFI, as a preventive measure when it still wasn't clear how linux interacted with that famous samsung uefi bug.
Looking in:

         http://lxr.free-electrons.com/source/drivers/platform/x86/samsung-laptop.c

I see that the following lines prevent the module from being initialized when you use UEFI, and so keyboard backlighting isn't enabled:

             1548 if (efi_enabled(EFI_BOOT))
             1549 return -ENODEV;

If those two lines were introduced as a preventive measure or as a real fix for the famous samsung UEFI bug, I don't know. I have a series 5 NP530U3C which doesn't have backlighting. DO NOT uncomment those lines and recompile the kernel, unless some expert on that old famous UEFI bug says its ok to do so.

But again, it is a separate issue and it's clear that the lack of keyboard backlighting is a software thing and not related to the bugs fixed here by my workaround, by unblocking the EC embedded controller.

The workaround fix I posted in posts #101 through #103 fixes the "problem state" that the laptop gets into from a "bad" suspend/resume, in which LID close events are not generated, and AC plugged in status is ignored, and battery charge changed events are not generated (and maybe some temperature alert / changed issues too). And of which one could only got out by hitting the reset button through the hole in the back while turned off.

Cheers!
--
Juan Manuel Cabo