What version of LE and what is it running on ? (your hardware)
I'm glad you asked that, cause I never realized that my system didn't auto update, I was still on 8.2.2 but then I manually updated to 8.2.3 and nothing changed at all.
I use a Logitech F710 which is similar to an XBOX360 controller.
Firstly you will also need a keyboard to SET the controller.
In the Input-> Controller menu select "Kodi" from the left hand side with the keyboard. Then when the countdown timer starts on the "A" button, select that button on the controller. If all goes well it will move to "B", "X", "Y" etc. If one of the buttons fails, just select it again with the keyboard and try again.
If nothing happens, check cat .kodi/temp/kodi.log for something like inpiut/jr0 not found. If that is the case restart Kodi with systemctl restart kodi.
Also I have found that if a button is not pressed on the controller during boot, LE will fail to recognise the controller, so if rebooting hit a button a number of times.
In the Settings -> Input section, I'm not sure if it matters, but "Peripherals" is grayed out.
Also, back when I was on Openelec and configuring RetroArch to work, I was doing a lot of customizing to get my Xbox 360 controllers to identify themselves (the lights surrounding the Xbox button, the player 1 light, player 2, etc) and after a lot of trial and error, I did finally get that to work. But I could never get my Xbox One controller to work (it's a wireless controller with the USB cable connected, the same way I use this controller on the PC). But now when I connect either of these controllers, the lights just blink and the Xbox One controller will eventually just turn off.
When I go to configure the controller, I select "Kodi" from the left hand side, and that takes me to the "button A" section, and no matter what I press on my controller, nothing happens. I've tried both controllers.
There is nothing in the kodi.temp log about anything that I can tell is related to controller inputs at all, I can't even see in there anything that even attempted to map my controllers.
Finally, I did try pressing buttons during boot, and it didn't change anything.
I am open to try anything and everything! Thanks for both of you for helping thus far!