From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthias Fuchs Subject: Enabling auto RS485 half-duplex control Date: Wed, 17 Dec 2008 22:24:13 +0100 Message-ID: <200812172224.13608.mfuchs@ma-fu.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-in-05.arcor-online.net ([151.189.21.45]:58927 "EHLO mail-in-05.arcor-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751460AbYLQVYU (ORCPT ); Wed, 17 Dec 2008 16:24:20 -0500 Received: from mail-in-10-z2.arcor-online.net (mail-in-10-z2.arcor-online.net [151.189.8.27]) by mail-in-05.arcor-online.net (Postfix) with ESMTP id 64801183613 for ; Wed, 17 Dec 2008 22:24:18 +0100 (CET) Received: from mail-in-04.arcor-online.net (mail-in-04.arcor-online.net [151.189.21.44]) by mail-in-10-z2.arcor-online.net (Postfix) with ESMTP id 4CE4C23D2F3 for ; Wed, 17 Dec 2008 22:24:18 +0100 (CET) Received: from bunny.home (dslb-088-070-062-165.pools.arcor-ip.net [88.70.62.165]) by mail-in-04.arcor-online.net (Postfix) with ESMTP id 2D35A1BF572 for ; Wed, 17 Dec 2008 22:24:15 +0100 (CET) Received: from fox.localnet (fox.home [192.168.2.13]) by bunny.home (Postfix) with ESMTPS id 4E66525104CB for ; Wed, 17 Dec 2008 22:24:11 +0100 (CET) Content-Disposition: inline Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: linux-serial@vger.kernel.org Hi, some Exar UARTs like the XR16C2850 support a feature called auto RS485 half-duplex control. In this mode the RTS line has a special role when using the UART for RS485 communication. I did not find a way to enable this mode through the standard serial driver. The UART is is detected correctly but there seems to be no way to enable this mode out of the box. So what's the best way to implement this? A new ioctl? Any idea? Matthias