[angry_octet]

Yes but if it is patented that doesn't mean it is secret -- in fact the opposite. I can copy the code but I can't sell a product using it without getting a licence or risk being sued. Obviously I can't licence it as GPLv3. But I don't see why the driver implementation should be so closed.

[hyperman1]

Because you don't hide the driver to hide what's in your patent. You hide the driver to hide code that violates someone else's patent.

'Patent minefield' means there are so many patents for so many basic things it's impossible to do anything without violating something. You'll never know you've violated a patent until your competitor sues you. A lot of these patents are probably invalid, but the fights in court will take years, judgement will sometimes happen by someone without know how, and losing 1 fight will cause you severe damage.

The 'solution' is trying to hide all your violations by closing the driver. Reverse engineering costs a lot, so if someone is doing it to find your patent violations, you build your own patent war chest and cross license with them - they have engineers so they probably produce something that has violations for your patents.

[angry_octet]

Ah, that makes total sense. Makes you wonder how they avoided this situation with RISC-V (they say via identification of prior art), but graphics does seem to be worse patent-wise (though ARM is notoriously litigious).