On Thu, May 06, 2021 at 10:44:25AM +0200, Robert Wolters wrote: > Why: FTDI USB serial speed issue with SCS P4 Dragon short-wave modems, > a custom baud-rate is required > > Solution: set special baud-rate by setting a custom divisor on 38400B You can set any baudrate you want using the TCSETS2 interface, and you can still use the legacy TIOCSSERIAL ioctl interface (e.g. setserial) if you prefer. No need to be hardcoding anything in the kernel. Johan