From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Fulghum Subject: Re: serial flow control appears broken Date: Fri, 27 Jul 2007 19:34:01 +0000 (UTC) Message-ID: <46D33636.7070200@microgate.com> References: <46A84B4A.6070902@shaw.ca> <46A8C6F1.4080309@howardsilvan.com> <20070726173121.70088a92@the-village.bc.nu> <46A98845.8010806@howardsilvan.com> <46A9F712.70706@imap.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from adsl-70-250-156-241.dsl.austtx.swbell.net ([70.250.156.241]:57241 "EHLO gw.microgate.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758338AbXG0Tdv (ORCPT ); Fri, 27 Jul 2007 15:33:51 -0400 Date: Mon, 27 Aug 2007 14:38:14 -0600 In-Reply-To: <46A9F712.70706@imap.cc> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Tilman Schmidt Cc: Lee Howard , Alan Cox , Robert Hancock , linux-serial@vger.kernel.org, tytso@mit.edu, rmk@arm.linux.org.uk, linux-kernel@vger.kernel.org Tilman Schmidt wrote: > Could this be related? > > http://lkml.org/lkml/2007/7/18/245 > > Quote: > "I've recently found (using 2.6.21.4) that configuring a serial ports > (ST16654) which use the 8250 driver using setserial results in the > UART's FIFOs being disabled (unless you specify autoconfig)." That would make sense. Lee's error is a hardware FIFO overrun which could occur if the FIFO is being disabled as described in your link (by trying to set the uart type with setserial). Since the tty flow control is only triggered by the line discipline in response to ldisc buffer levels and not hardware FIFO overruns, you would never see any flow control action as reported by Lee. -- Paul Fulghum Microgate Systems, Ltd.