From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ed Vance Subject: RE: 16850 automatic RTS/CTS Date: Wed, 8 May 2002 09:58:54 -0700 Sender: linux-serial-owner@vger.kernel.org Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Return-path: List-Id: linux-serial@vger.kernel.org To: 'Guennadi Liakhovetski' Cc: tytso@mit.edu, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org On Wed, May 08, 2002, Guennadi Liakhovetski wrote: > > As of 2.5.6 there is some support in the serial driver for the > 16850 automatic hardware handshake feature, in particular the > automatic CTS is enabled, but not the automatic RTS. Nor are > the hysteresis levels set. Why? I tried enabling all these > features, it helps a good deal improving the reliability of the > data transfer, but still, at high baud-rates (460800, 921600) > and in the presence of user-space load data can be overwritten > in the driver's buffer. Why isn't this checked? Hi Guennadi, Like so many other good ideas, this feature support is not already there simply because nobody has submitted a patch for it, yet. (and followed-up/lobbied with sufficient tenacity and grace) Also, be aware that there is in progress a rewrite of the serial driver subsystem for 2.5. See Russell King's entry in the maintainers list. I'm only on the 2.4 side, but I would like to see a tested patch against either 2.5 or 2.4 for fixup of 16850 support. Since you have the 16850 hardware (and I don't), please consider creating a patch to serial.c and friends that adds this feature support and posting it for discussion to linux-serial@vger.kernel.org. Put enough comments at the top so anyone with the datasheet can understand your intent. Thanks, Ed ---------------------------------------------------------------- Ed Vance edv@macrolink.com Macrolink, Inc. 1500 N. Kellogg Dr Anaheim, CA 92807 ----------------------------------------------------------------