From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E135C433EF for ; Fri, 19 Nov 2021 11:17:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1616161353 for ; Fri, 19 Nov 2021 11:17:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234752AbhKSLU5 (ORCPT ); Fri, 19 Nov 2021 06:20:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229521AbhKSLU5 (ORCPT ); Fri, 19 Nov 2021 06:20:57 -0500 Received: from bmailout3.hostsharing.net (bmailout3.hostsharing.net [IPv6:2a01:4f8:150:2161:1:b009:f23e:0]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0CF6AC061574 for ; Fri, 19 Nov 2021 03:17:56 -0800 (PST) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS DV RSA Mixed SHA256 2020 CA-1" (verified OK)) by bmailout3.hostsharing.net (Postfix) with ESMTPS id 866D9103B1FD9; Fri, 19 Nov 2021 12:17:54 +0100 (CET) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 627424A8C0; Fri, 19 Nov 2021 12:17:54 +0100 (CET) Date: Fri, 19 Nov 2021 12:17:54 +0100 From: Lukas Wunner To: Jan Kiszka Cc: Su Bao Cheng , Su Bao Cheng , gregkh@linuxfoundation.org, linux-serial@vger.kernel.org, chao.zeng@siemens.com Subject: Re: [PATCH] Revert "serial: 8250: Don't touch RTS modem control while in rs485 mode" Message-ID: <20211119111754.GB9692@wunner.de> References: <20211027111644.1996921-1-baocheng.su@siemens.com> <20211027113938.GA9373@wunner.de> <61ace2ea-e0b3-599a-3098-8e8a2a4772fa@siemens.com> <68b02a33-6cfb-5139-f8b3-20f289c2befc@siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <68b02a33-6cfb-5139-f8b3-20f289c2befc@siemens.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On Fri, Nov 19, 2021 at 09:43:12AM +0100, Jan Kiszka wrote: > Digging a bit deeper: One issue of the original patch was definitely > that it tried to sanitized mctrl inside serial8250_do_set_mctrl, rather > than serial8250_set_mctrl. That caused alternative set_mctrl handler to > become out of sync /wrt mctrl. Just look at omap8250_set_mctrl, how it > will work on the unsanitized value. All omap8250_set_mctrl does is enable or disable autoRTS if autoRTS is used. Are you using autoRTS on this port? That's one of several pieces of information that I'm missing here to understand what's going on. Thanks, Lukas