Re: serial flow control appears broken

From: Paul Fulghum
Date: Fri Jul 27 2007 - 15:08:24 EST


On Fri, 2007-07-27 at 12:22 -0600, Robert Hancock wrote:

> In this situation, though, it appears it's not the TTY buffers that are
> filling but the UART's own buffer. I would think this must be caused by
> some kind of interrupt latency that results in not draining the FIFO in
> time.

You are right, this error is output when the character flag TTY_OVERRUN
is encountered by n_tty.c which should be set by the driver
in response to a hardware FIFO overrun (not an ldisc buffer overrun).

I can't see anyplace in serial_core.c or 8250.c that sets TTY_OVERRUN.


--
Paul Fulghum
Microgate Systems, Ltd

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