From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752037AbcFVKAA (ORCPT ); Wed, 22 Jun 2016 06:00:00 -0400 Received: from mail-lb0-f179.google.com ([209.85.217.179]:32857 "EHLO mail-lb0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751425AbcFVJ7Y (ORCPT ); Wed, 22 Jun 2016 05:59:24 -0400 Subject: Re: [PATCH v2] tty: serial: msm: Don't reconfigure same baud rate To: Nicolas Dechesne , Bjorn Andersson References: <1465844571-1229-1-git-send-email-bjorn.andersson@linaro.org> <1466101475-8851-1-git-send-email-bjorn.andersson@linaro.org> Cc: Andy Gross , Stephen Boyd , David Brown , Greg Kroah-Hartman , Jiri Slaby , linux-arm-msm , linux-soc@vger.kernel.org, linux-serial@vger.kernel.org, lkml From: Srinivas Kandagatla Message-ID: <576A6168.1000901@linaro.org> Date: Wed, 22 Jun 2016 10:59:04 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/06/16 10:43, Nicolas Dechesne wrote: > On Fri, Jun 17, 2016 at 1:02 PM, Nicolas Dechesne > wrote: >> wrote: >>> msm_set_termios() is called whenever the tty is opened. Setting the baud >>> rate requires a full reset of the msm serial block, even when the rate >>> is unchanged. In the case when the same uart is used as console this >>> reset will discard any console output data still being clocked out of >>> the TX fifo. >>> >>> By skipping the rate-change in the case where the baud rate is unchanged >>> since last request we can avoid the reset and the discarding of the >>> data. >>> >>> Signed-off-by: Bjorn Andersson >> >> >> Tested-by: Nicolas Dechesne >> >> I no longer see this type of corruption on serial console >> >> [ 6.325118] ALSA device �[ 6.333338] Freeing unused kernel >> memory: 572K (ffffffc000c10000 - ffffffc000c9f000) >> [ 13.800269] remoteproc2: remote processor a20400�[ OK ] Started >> Start the WCN core. >> [ � Starting Update UTMP about System Runlevel Changes... > > > oops. today i tried on APQ8064 boards , both IFC6410Plus and SD > 600eval, and I can no longer 'type' into the serial console, I can get > debug messages though. Reverting this change 'fixes' the problem. Am also hitting the same issue as Nico on IFC6410 with this patch. > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >