Allwinner has been accused multiple times in the past of violating the GPL license by not providing Linux/Android kernel source code or U-Boot source, along with using LGPL-licensed code within their binary blobs, etc. Today there's new "definitive proof" of Allwinner's GPL violations...
February 25, 2015
More Proof That Allwinner Is Violating The GPL
Read more at Phoronix