Any comments by the postmarketOS folks? They have successfully upstreamed kernel patches in the past, and might be able to drive this effort for the original PinePhone and PineTab hardware.
I would recommend reading for some background:
https://drewdevault.com/2022/01/18/Pine64s-weird-priorities....
https://drewdevault.com/2022/08/18/PINE64-let-us-down.html
https://blog.brixit.nl/why-i-left-pine64/ (Pine64's response: https://www.pine64.org/2022/08/18/a-response-to-martijns-blo... )
Also, frankly, when we get a response like this: https://mastodon.social/@CounterPillow/110589778080526844 from a Pine64 developer when we worked to port over the PineTab2 to Mobian, it really doesn't make me want to work with them.