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 X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3AADAC433DF for ; Mon, 24 Aug 2020 09:46:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 163CB2071E for ; Mon, 24 Aug 2020 09:46:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729073AbgHXJq3 convert rfc822-to-8bit (ORCPT ); Mon, 24 Aug 2020 05:46:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:34370 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728935AbgHXImU (ORCPT ); Mon, 24 Aug 2020 04:42:20 -0400 From: bugzilla-daemon@bugzilla.kernel.org To: linux-usb@vger.kernel.org Subject: [Bug 208959] USB-serial (mct_u232): bit7=1 when tty is set to cs7? Date: Mon, 24 Aug 2020 08:42:19 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: USB X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: low X-Bugzilla-Who: johan@kernel.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=208959 --- Comment #1 from Johan Hovold (johan@kernel.org) --- On Wed, Aug 19, 2020 at 02:52:47AM +0000, bugzilla-daemon@bugzilla.kernel.org wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=208959 > > Bug ID: 208959 > Summary: USB-serial (mct_u232): bit7=1 when tty is set to cs7? > Product: Drivers > Version: 2.5 > Kernel Version: 5.7.0 > Hardware: All > OS: Linux > Tree: Mainline > Status: NEW > Severity: low > Priority: P1 > Component: USB > Assignee: drivers_usb@kernel-bugs.kernel.org > Reporter: mslade@epic-code.com.au > Regression: No > > I'm not 100% certain this is a bug, please let me know if this is expected > behavior. > > I have hooked an old serial mouse up to a USB serial device, USB ID 0711:0230 > (part of an circa 2000 Targus port replicator) > > when I configure it with the appropriate 1200 baud and 7 bit char width, the > bytes that come through /dev/ttyUSB0 all have bit7 set to 1. > > This behavior is in contrast to an old serial port on a box running a 2.4.19 > kernel. > > Is there a standard for the value that non-data bits should be set to? This sounds like a configuration issue. If the mouse is indeed using 7n1 and the converter is expecting 8n1 you could end up with bit 7 always set on input. Can you verify that the converter is configured correctly, for example, by reading out the termios settings, enabling debugging and/or connecting it to another serial port configured for 7n1? Johan -- You are receiving this mail because: You are watching the assignee of the bug.