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=-6.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 D4955C07E96 for ; Thu, 8 Jul 2021 06:17:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A8D0D61CE5 for ; Thu, 8 Jul 2021 06:17:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229701AbhGHGUf (ORCPT ); Thu, 8 Jul 2021 02:20:35 -0400 Received: from out2-smtp.messagingengine.com ([66.111.4.26]:59823 "EHLO out2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229658AbhGHGUe (ORCPT ); Thu, 8 Jul 2021 02:20:34 -0400 Received: from compute2.internal (compute2.nyi.internal [10.202.2.42]) by mailout.nyi.internal (Postfix) with ESMTP id E4E1D5C00E6; Thu, 8 Jul 2021 02:17:52 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Thu, 08 Jul 2021 02:17:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kroah.com; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm1; bh=qJr6/XutY8X8NyuozIa9nkcxlar Nm26YSQ/XYcf/t9k=; b=D1oRuwySivjQi+Dk2EWquKLlcTCHvj5Tf6AMTalQTzA FIMwTxDHOYT3QfKgYKpYLNvhtpcwzwkXoiMwn+4fYfrUWkeY97CfBAkzXYgCNnmz mX8VvvAN2gl59RLUnl/CQuHx94fGzbRKRwWVJKDQz1uqAbCJAXA0f26MRdt5CnfE gezGRxyPct42k6ogjmz3a3oGQylt4yaXrhsdH9fOOF3WI6FMpWsIU0R8VkB1pP67 15yNiIhe0X3RQz+u5KXopddlb562uzIfRsq68y/zbO1gIkgLq019xGGwCDf87Cqv vdd1r65goPWBFsXQKiDzQ6yJRGqRZy7J/INQugRPvqQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm3; bh=qJr6/X utY8X8NyuozIa9nkcxlarNm26YSQ/XYcf/t9k=; b=tiX1ietj3mIN6pfI40vVu2 y/fSjUTiLZp2bqG/t8X4JCAzzPZkHqaXSfKuK8rwLe/IXsfkCO51o25H2Lo7TIlv oWgaqw/CgHEuBtOuNTsOV8R3jSxm4GsKeH64mMMSOcva+4wm7sn8eS/RcmLDjkKt AQXm5tk74ktpeDgTvnaANNnMA/mkp1MvVofvcL/YXpTJEYFio+hG5XJjSG11wgsV uqTSSJFKZStI5jrrI31gM3vWysmAG9+GhH4B3JVn5/tp1OI7h7bN3gtCLdWzpodT 3wWxe63RHdavzc6Lr05mZwZVpyM6QvXMCa2CD+0lkZYM0WnBXO6tzv7CHkcvYAqg == X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvtddrtdefgdeludcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecunecujfgurhepfffhvffukfhfgggtuggjsehttdertd dttddvnecuhfhrohhmpefirhgvghcumffjuceoghhrvghgsehkrhhorghhrdgtohhmqeen ucggtffrrghtthgvrhhnpeejkefhhfegtdefueevgfduueehtdeiiefhjeefteejkeefhe ejfeeuuddttdffheenucffohhmrghinhepvghlmhgvlhgvtghtrhhonhhitghsrdgtohhm pdgrmhgriihonhdrtghomhenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmh grihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomh X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 8 Jul 2021 02:17:52 -0400 (EDT) Date: Thu, 8 Jul 2021 08:17:49 +0200 From: Greg KH To: Jeffrey Walton Cc: linux-usb@vger.kernel.org Subject: Re: CH341 driver and the 5.4 kernel Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Wed, Jul 07, 2021 at 05:48:48PM -0400, Jeffrey Walton wrote: > > I'm trying to track down the cause of some garbage in a response when > > using an ELM327 (https://www.elmelectronics.com/ic/elm327/) with a > > CH341 serial controller. > > To follow up on this... > > Here's the device I am working with: OBD2 Scanner Adapter OBD2 ELM327 > USB Cable Car Code Reader Diagnostic Scan Tool v1.5, > https://www.amazon.com/gp/product/B0897G6BMZ. It has a controller for > interfacing with a vehicle's OBD II, and a CH340 for USB > communications. > > I contacted ELM Electronics Support [1] about the garbage I was > seeing. I thought I may have the serial port misconfigured in a subtle > way. Support wrote back that they did not make the OBD controller in a > v1.5. They make, among others, v1.4b and v2.0 [2]. It appears the OBD > chip is a knockoff. > > I also think I tracked down the vendor for the CH340. It is a company > called WCH. It looks like they provide a GPL'd driver for Linux [3] > and name the driver ch34x. The driver is a lot different than the one > provided by the Linux kernel [4]. > > What I don't know is, if the WCH serial controller is another > knock-off. If it is an ill-performing knock-off, then that may explain > the problems using the existing Linux driver. Using the WCH driver > probably explains why things work under Windows. The WCH driver may > fix the problems I am seeing under Linux. If you could try the latest 5.13 kernel release to let us know if that solves the issues for you or not, that would be great as a lot of work has recently gone in for these "odd" ch340-like devices. thanks, greg k-h