Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753526AbbH0Gne (ORCPT ); Thu, 27 Aug 2015 02:43:34 -0400 Received: from mail-yk0-f177.google.com ([209.85.160.177]:33949 "EHLO mail-yk0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751549AbbH0Gnc (ORCPT ); Thu, 27 Aug 2015 02:43:32 -0400 MIME-Version: 1.0 In-Reply-To: <20150826181505.GA32712@localhost> References: <20150826170440.GB28324@localhost> <20150826180930.21386.qmail@stuge.se> <20150826181505.GA32712@localhost> Date: Thu, 27 Aug 2015 12:13:32 +0530 Message-ID: Subject: Re: Likely issue with ch341 kernel-module/driver From: Ajay Garg To: Johan Hovold Cc: Peter Stuge , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2289 Lines: 79 I started in the morning to build the driver from the source provided by the vendor, but it was written in the times of kernel-version 2.4, and I got hopelessly stuck. Wanting to take a break, I reset my setup, and VERY strangely, what I now observe is :: a) I am NOT able to send anything from the embedded-system to putty-session (nothing appears at all on the putty session). b) Receive is working perfectly (anything I type in the putty-session is received fine in the embedded-application). Not sure what the hell is going on :( Also, as per http://lxr.free-electrons.com/source/drivers/usb/serial/ch341.c?v=3.16, the particular serial-USB-adapter device is added into the id_table, so seems supported as per say. Additionally, the message has changed to ########################################################### usb 2-2: device not accepting address 8, error -71 ########################################################### Completely lost :( On Wed, Aug 26, 2015 at 11:45 PM, Johan Hovold wrote: > On Wed, Aug 26, 2015 at 08:09:30PM +0200, Peter Stuge wrote: >> Johan Hovold wrote: >> > On Wed, Aug 26, 2015 at 09:39:36PM +0530, Ajay Garg wrote: >> .. >> > > garbage characters transmitted from embedded-device >> .. >> > > It seems that there is some issue with the driver. >> > >> > Why do think it's a driver issue? >> >> I can confirm similar issues with the in-tree driver and my hardware. > > What hardware is that? > >> > > Any chance this can be made to work? >> >> Ajay, please try building the vendor driver. That works well for me. > > Yes, please do. > >> > > Any upgrade that might solve the issue? >> >> There is no upgrade. Someone needs to spend a day or so on adding >> functionality from the vendor driver to the in-tree driver, in a >> backwards-compatible way. >> >> > Looks like a hardware issue, I'm afraid. >> >> When I got garbage from the in-tree driver it was indeed a driver issue. > > That's good to hear. Care to write up a patch? :) > > Thanks, > Johan -- Regards, Ajay -- 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/