For T1, it seems like Master is pretty important. Do you have
information to be able to return the current Master/slave
configuration, or allow it to be configured? See the nxp-tja11xx.c
for an example.
I think it's possible to return a Master/Slave configuration.
By the way, do you need the cable test function as implemented in nxp-tja11xx.c?
Thanks & Best Regards,
Yuusuke Ashiduka