From: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2005@gmx.net>
To: linux-serial@vger.kernel.org
Subject: Serial console UART confusion after machine S3 suspend and resume
Date: Thu, 03 Feb 2005 18:16:10 +0100 [thread overview]
Message-ID: <42025C5A.7070709@gmx.net> (raw)
Hi,
on resume from S3, my serial console prints garbage and stops working.
If I disconnect the console while my machine is sleeping and reconnect
immediately after, the serial console still prints garbage on resume
but the follwowing command on my machine fixes the output for all
subsequent kernel messages sent to the serial console.
echo foo >/dev/ttyS0
Nothing besides outputting something to ttyS0 helps. Disconnecting
and reconnecting, both logically and physically, doesn't have any
positive effect.
Could it be that the UART state is out-of-sync or something like that
after resume and the serial console code doesn't notice, but the
"normal" serial code notices and fixes things up?
Are there any debugging options/patches/tips to find out what happens
exactly? The machine works just fine after resume, so I could read
dmesg for debugging output.
Regards,
Carl-Daniel
--
http://www.hailfinger.org/
reply other threads:[~2005-02-03 17:15 UTC|newest]
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