Re: [SOLVED] Serial buffer corruption [was Re: FTDI usb-serial possible bug]

[Antonino Ingargiola]

On 5/4/07, Paul Fulghum <paulkf@xxxxxxxxxxxxx> wrote:
> On Fri, 2007-05-04 at 21:06 +0200, Antonino Ingargiola wrote:
>
> > Filling with echo console-screen.sh I've found that the blocking command is:
> >
> >     unicode_start 2> /dev/null || true
> >
> > or at least the echo before this command is the last shown.
>
> I still don't know what is blocking.
>
> It is possible some tty device is operating with an improperly
> initialized tty structure. I vaguely remember some console code
> creating its own minimally initialized 'dummy' tty structure.
>
> This might be causing the new flush code to hang.
>
> Try this patch which does not call the flush unless a line
> discipline is attached to the tty. That should indicate
> a normally initialized tty structure.

Tried. Nothing changes with this patch. I'm booting the patched kernel
commenting out the unicode_start line for now, and there aren't other
"system" problems.

I confirm the behavior previously posted for the serial devices on
flush with this patch too.

"With the patch, flushing the input results effectively in a complete flush.
However after doing the flush I can't read [further] chars [sent to
the serial port]
without closing and reopening the port. I've verified this behavior both
communicating between two serial ports and both communicating with an
usb-serial device (driver cdc-acm)."

Regards,

 ~ Antonio
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