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    SubjectRe: [PATCH] atmel serial reduce trasmitting window & code style patch

    Hi,

    > Ok, the patch seems to make sense, but your description
    > isn't very good...
    ok
    > * What problem does this patch solve (I think I know it,
    > but I don't
    > want to guess.)
    I try to resolve this problem:
    The serial is set in interrupt mode 9600, and trasmit a lot of data.
    The serial receive data from another device. The receive buffer is
    1024 bytes and the trasmit buffer is an XMIT_SIZE. So when the tasklet
    start to trasmit, it can loose data.
    > * This patch doesn't really reduce any "TX
    > window" since the window
    > simply didn't exist before (or was infinitely long
    > or whatever.) I
    > think you should mention that this limitation is a new
    > thing.

    > * Why is 32 a good value?
    >
    ... I don't know a good value, because the tasklet can be preempted,
    and the receiving buffer can be fill in background. It is hard to choose
    a good value...
    > Also, do we need to reschedule the tasklet if we terminate
    > the loop
    > because of this limit? I think we can get away with not
    > doing it since
    > the interrupt handler will be triggered as soon as we
    > enable the TX
    > interrupt. But perhaps we should avoid enabling the
    > interrupt and
    > schedule the tasklet since we _know_ there's a TX
    > interrupt pending?
    >
    Ok, you are right, schedule the tasklet is better. I do some
    test and post another patch.

    Michael


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