The board I'm working has one serial console (ttyS0) and I would like to make my kernel module show any errors to this serial console. I understand that one possibility would be using console=ttyS0 parameter to print messages appear on the serial, however, for my case specifically I cannot set this parameter (e.g. my bootloader doesn't allow setting console=...) and my module messages end up being lost. Also, I understand that these kernel messages could be retrieved in dmesg/syslog but that's not what I'm looking for.
Is there a way to make my module write to a serial console(s) (e.g. ttyS0) regardless of what is defined for the console=... kernel parameter?