Samsung S5 mini supports Gamepad through OTG?
There is a fix for this OTG here http://forum.xda-developers.com/galaxy-s5-mini/help/usb-host-otg-t2855675/page2 BUT you have to install a custom Kernel. I did this on mine and it means you cannot get the 5.1.1 update from your carrier. SO i had OTG working fin for a while. Then reset phone so i could update to 5.1.1 via KIES but now now OTG again. Not sure if I can use the customer Kernel with 5.1.1 , did it so long ago now id be no help helping anyone, but it is my 2 cents worth.