• Christian Melki's avatar
    8250.c: less than 2400 baud fix. · f9a9111b
    Christian Melki authored
    We noticed that we were loosing data at speed less than 2400 baud.
    It turned out our (TI16750 compatible) uart with 64 byte outgoing fifo
    was truncated to 16 byte (bit 5 sets fifo len) when modifying the fcr
    reg.
    The input code still fills the buffer with 64 bytes if I remember
    correctly and thus data is lost.
    Our fix was to remove whiping of the fcr content and just add the
    TRIGGER_1 which we want for latency.
    I can't see why this would not work on less than 2400 always, for all
    uarts ...
    Otherwise one would have to make sure the filling of the fifo re-checks
    the current state of available fifo size (urrk).
    Signed-off-by: default avatarChristian Melki <christian.melki@ericsson.se>
    Cc: stable <stable@vger.kernel.org>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    f9a9111b
8250.c 82.6 KB