FIFO_TRIGGER_14 is excessively optimistic.

That's why we *don't use it*.  I quote, from the code itself:

                if (sc->sc_hwflags & COM_HW_FIFO)
                        outb(iobase + com_fifo,
                            FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST |
                            FIFO_TRIGGER_8);

FIFO_TRIGGER_14 is used only during the probe.

Now, one could argue that this should vary depending on the speed of the
serial link.


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