This is just broadcom sta driver source with latest kernel patches (mainly patches applied to original source from bcmwl-ubuntu repo on github) and patches for kernel version 4.0.0 (applied by me). This is just a repo for this driver to make wifi working on my dell m4800 with a custom built vanilla kernel of my choice (not ubuntu one).
Just make, sudo make install, sudo depmod, sudo modprobe wl and your wifi is up and running!
(if you don't compile other wifi modules, like I do, you'll also need to cd /lib/modules/uname -r/ && sudo mkdir kernel/drivers/net/wireless)