Choose older MULTIPORT version, because lastest bde version
not worked.
Don't force HUPCL for bidirectional case.
From bde:
Use bit (1 << (16 + 4)) in schedsoftcom() to avoid clash with
non-serial h/w on IRQ4.
Allow FIFO_TRIGGER in config.
Clear com->mcr_image when clearing mcr for init of 4port. The
usual value MCR_IENABLE should have broken 4ports unless
something happened to clear it later.
Turn off interrupts as well as DTR after an error waiting for
carrier (bidir dialin case).
Drain fifo more carefully.
Don't hang up if debugging.
Rearrange siointr() -> siointr1() for multiport case for speed,
lower latency and clarity.
Use suser() to check perms.
Provide missing splx() after failed perms checks.
c_ispeed == 0 means c_ispeed = c_ospeed (POSIX).
Set parameters (except speed) for c_ospeed == 0 as well as
hanging up.
Better initialization for console (fifo stuff...).
Misc. cleanups.
Fix dead hang if modem power is off.
e58072bda5