Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752617AbbH0Jpw (ORCPT ); Thu, 27 Aug 2015 05:45:52 -0400 Received: from mail-lb0-f176.google.com ([209.85.217.176]:33931 "EHLO mail-lb0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752479AbbH0Jpu (ORCPT ); Thu, 27 Aug 2015 05:45:50 -0400 Date: Thu, 27 Aug 2015 11:45:49 +0200 From: Johan Hovold To: Ajay Garg Cc: Johan Hovold , Peter Stuge , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Subject: Re: Likely issue with ch341 kernel-module/driver Message-ID: <20150827094549.GB3552@localhost> References: <20150826170440.GB28324@localhost> <20150826180930.21386.qmail@stuge.se> <20150826181505.GA32712@localhost> <20150827073759.GC32712@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1231 Lines: 37 On Thu, Aug 27, 2015 at 01:57:01PM +0530, Ajay Garg wrote: > Hi John. > > On Thu, Aug 27, 2015 at 1:07 PM, Johan Hovold wrote: > > > > Try to see if you can get the device to work reliably with some other > > driver (vendor driver or other OS) to rule out a broken device. > > > > I tested the serial-usb adapter using a loopback-hardware-tool > (confirmed to be perfect). > > Using this, I see what I type, echo it back, and see what I receive. > > The putty session-settings are standard one - 9600, 8N-1, no parity. > > The byte flow is > putty-on-laptop => usb-interface => serial-interface => loopback => > serial-interface => usb-interface => putty-on-laptop. > > Thereafter, following are the echo-sequences I see :: > > a ==> 0 > b ==> ' > c ==> N > > This (I guess) confirms a problem on (at least) the driver-side. Not unless you confirm that the same setup works when using a different driver, right? Otherwise, it could still be a hw issue. Johan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/