General Backlit Keyboard Enabling Instructions

It's been a while since I've been on FreeBSD, and I am thinking about putting it on the laptop I have now, but I really like my backlit keyboard and I don't want to lose that functionality. I searched the laptop compatibility page but mine isn't there and I'm not sure how to go about knowing whether it will work or not. It is a Dell Latitude E5520. A quite nice laptop. There is a similar lower end model that is supported by FreeBSD, but I didn't find any info about whether it has a backlit keyboard or not and if it is enabled. I noticed there is something about acpi settings to modify depending on what kind of hardware it is, but I am not sure how to find what kind I have. All I see in my system settings is that it is Microsoft ACPI compliant, but no other specifics. I have to hold the Fn key and press the right arrow to control it, so presumably it uses some software to control. Preferably I would like to know the solution before I install and try to figure it out, only to find it doesn't work. Namaste.
These kind of functions are usually handled by proprietary usb drivers.
For example to activate special functions of some Laptop HP Keyboard, one must choose an alternate Microsoft keyboard driver adding a HP module.

I am afraid you won't find any solution for FreeBSD....

The sole solution is to try


This module can activate sometimes some extra functions of USB keyboards, but with various result, sometimes you must deinstall it as it disturbs more that it solves.

Sometimes some functions can be directly handled by the BIOS if backlight function is controlled independently from the USB bus.

For example I have a tactile sound volume adjuster which works perfectly under any OS, including FreeBSD, but it seems to be handled directly by the BIOS.