From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Howard Subject: Re: serial flow control appears broken Date: Fri, 27 Jul 2007 11:11:42 -0700 Message-ID: <46AA355E.20901@howardsilvan.com> References: <46A84B4A.6070902@shaw.ca> <46A8C6F1.4080309@howardsilvan.com> <46AA2748.80703@howardsilvan.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from gateway.howardsilvan.com ([64.146.212.27]:52192 "EHLO mail.howardsilvan.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754087AbXG0SM6 (ORCPT ); Fri, 27 Jul 2007 14:12:58 -0400 In-Reply-To: Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: "Maciej W. Rozycki" Cc: Robert Hancock , linux-serial@vger.kernel.org, tytso@mit.edu, rmk@arm.linux.org.uk, linux-kernel@vger.kernel.org Maciej W. Rozycki wrote: > The TTY line discipline driver could do that based on the amount of >received data present in its buffer. And it should if asked to (a brief >look at drivers/char/n_tty.c reveals it does; obviously there may be a bug >somewhere though). So could e.g. the SLIP and PPP line discipline >drivers, though the criteria might be different (apparently they do not, >which is a shame). > > The serial drivers have nothing to do about it -- all they can do is >pushing data upstream, to the discipline driver. They can provide an >interface to hardware flow control features though, if implemented by a >given UART. > Thank you for this clarification. So I should have more correctly been saying that "tty flow control appears broken". Right? I've asked the manufacturer to take a look at drivers/char/n_tty.c to see if they can't see anything obvious. Thanks, Lee.