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=-5.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 5F7BDC63793 for ; Thu, 22 Jul 2021 07:51:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3A49160249 for ; Thu, 22 Jul 2021 07:51:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230306AbhGVHKc (ORCPT ); Thu, 22 Jul 2021 03:10:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:33824 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230284AbhGVHKb (ORCPT ); Thu, 22 Jul 2021 03:10:31 -0400 Received: by mail.kernel.org (Postfix) with ESMTPS id 2383B60249 for ; Thu, 22 Jul 2021 07:51:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1626940267; bh=qogvZo2NdofL1Rj1JlMKpXY1ouKb1vBPG8m/TchaFfI=; h=From:To:Subject:Date:In-Reply-To:References:From; b=uzG3R8rnve7bsWlA28sXgAXFIRAT8eI9e/DhHt7al2CfkkNsrtnOlss5aFroPPVhp cBeFt7gB9TVQshztDo8Drkg0S+ybaNL/Rh8QkeZEt4cMwHNdKtfwHsjT6u43OVpKg2 ax78pdcBLmTSyqs9wB5HpzaOpc1MuCOC8UJmEa9yiOP5/qQlQowpKX+B7N7+ZcAdYh 6/DN/WcpalSvm9Kgh4aIMNLEbr3jor0MoDc/jSi+KSTdz3fM+hWP2lfXT57rIZ2kGS Aa+gEIRZS+zME1MdgkCuUFfC8528US0vqsUhGcTQ6+VMKonLS/zgv8SeIRhvLytwtT Z03XDsMt1QRuQ== From: bugzilla-daemon@bugzilla.kernel.org To: linux-usb@vger.kernel.org Subject: [Bug 213771] ch341 USB-Serial converter receives but does not send Date: Thu, 22 Jul 2021 07:51:06 +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: normal 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: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=3D213771 --- Comment #4 from Johan Hovold (johan@kernel.org) --- On Wed, Jul 21, 2021 at 07:00:08PM +0000, bugzilla-daemon@bugzilla.kernel.o= rg wrote: > On Ubuntu, Shorting pins 2 and 3 of DB9 connector does not give back > characters > sent (no echo), nor typed strings are sent to other RS232 devices, despit= e of > communication settings. Characters from remote devices are correctly > received. > Using a null modem cable to other RS232 terminal shows that the local > terminal > receives, but does not transmit. What happens if you also short RTS and CTS? And are you able to change the baud rate at all? > Kernel: > Linux host 5.4.0-66-generic #74-Ubuntu SMP Wed Jan 27 22:54:38 UTC 2021 > x86_64 > x86_64 x86_64 GNU/Linux Please confirm using a recent mainline kernel (e.g. 5.13). > Device ID: > ID 4348:5523 WinChipHead USB->RS 232 adapter with Prolifec PL 2303 chipset This looks strange. I don't think these devices are based on (misspelled) Prolific PL2303 chips. This is possibly some kind of counterfeit device. You could try using the pl2303 driver. Please also post the output of lsusb -v. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=