I wasn't sure how you guys would have liked me to contribute, so I posted here on the forum first.
New pull request, rebased on today's official libreelec-12.2:
PR: rk322x: port from le12 to le12.2
Diff blob is the last commit, same as the text file that I had attached to the forum: 3bef6aa
May need a bit more cleanup, and may contain useless changes, it was just a quick and dirty port, only spent a day trying to compile it on latest LE12.2...