> The PineBook Pro was never fully supported by Linux despite shipping with Linux.
The postmarketOS folks have significant experience with mainlining kernel support for hardware that's only supported in downstream/vendor kernels. Please reach out to them and make sure they know about the issues; this work should be plenty relevant to them because Pine64 is also doing mobile HW.
Check out this FAQ that's scoped around a custom Arch Linux ARM but gives you an idea of the pain: https://github.com/SvenKiljan/archlinuxarm-pbp/blob/main/FAQ...
For thoughts on why Pine64 seems to be stuck in this state of never fully working hardware I can recommend Drew DeVault's blogpost: https://drewdevault.com/2022/01/18/Pine64s-weird-priorities....