Ubuntu 22.04 with Kernel 5.4

yarmooh New Member Posts: 7


I'm trying to upgrade existing installation of Ubuntu 18.04 to 22.04, but keep using upboard kernel 5.4 - because of compatibility issues I'm getting.

With Ubuntu 18.04 and kernel 5.4 I've got no issues with FBTFT screen and my FTDI board, but if I upgrade to 22.04 it comes with kernel 5.15, it boots fine, but FTDI does not work "Error occured: FTDI controller not initialized" and does not too, since lack of up2 gpio support in the kernel.
If I try to run kernel 5.4 from 18.04 OS does not boot at all, kernel panics on vfs: cannot open root device unknown block error -6

What may be the cause of it, or how can I port up2 kernel changes to kernel 5.15?