From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Vivier Subject: Broken serial port Date: Tue, 17 Jun 2014 20:48:04 +0200 Message-ID: <53A08D64.1060800@Vivier.EU> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Kv7XxoFbl6mDSrFHgaBJCsM8FdmxNpX62" Return-path: Received: from mout.kundenserver.de ([212.227.126.187]:49681 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754403AbaFQSsN (ORCPT ); Tue, 17 Jun 2014 14:48:13 -0400 Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Jiri Slaby , Greg Kroah-Hartman , Seth Bollinger This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --Kv7XxoFbl6mDSrFHgaBJCsM8FdmxNpX62 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hi, I'm not subscribed to these mailing lists, so CC: me. I'm playing for some days with a kernel 3.15 on an old mac performa 575 and it seems that the serial port is broken. When I log on using the console on the serial port it seems there is an screen refresh added after each character I send. A little demo : http://asciinema.org/a/10211 [at 3:20] I bisect and I found this commit : commit 717f3bbab3c7628736ef738fdbf3d9a28578c26c Author: Seth Bollinger Date: Tue Mar 25 12:55:37 2014 -0500 serial_core: Fix conditional start_tx on ring buffer not empty If the serial_core ring buffer empties just as the tty layer receives= an XOFF, then start_tx will never be called when the tty layer receives an XON as the serial_core ring buffer is empty. This will possibly leave a few bytes trapped in the fifo for drivers that disable the transmitter when flow controlled. Signed-off-by: Seth Bollinger Signed-off-by: Greg Kroah-Hartman If I revert it, all works fine : http://asciinema.org/a/10212 Regards, Laurent --Kv7XxoFbl6mDSrFHgaBJCsM8FdmxNpX62 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iEYEARECAAYFAlOgjWQACgkQNKT2yavzbFNb4gCglmLCQ7pVzeQHeBHD9tniaIaE 40oAoNckZ2E5GW6AkukqOWAiAJQUkuWm =7UPG -----END PGP SIGNATURE----- --Kv7XxoFbl6mDSrFHgaBJCsM8FdmxNpX62--