Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753217AbbDROmu (ORCPT ); Sat, 18 Apr 2015 10:42:50 -0400 Received: from mail-qk0-f173.google.com ([209.85.220.173]:35899 "EHLO mail-qk0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751893AbbDROmr (ORCPT ); Sat, 18 Apr 2015 10:42:47 -0400 Message-ID: <55326D65.7010609@hurleysoftware.com> Date: Sat, 18 Apr 2015 10:42:45 -0400 From: Peter Hurley User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Robert Baldyga , gregkh@linuxfoundation.org CC: akpm@linux-foundation.org, jslaby@suse.cz, cw00.choi@samsung.com, m.szyprowski@samsung.com, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] serial: samsung: fix serial console break References: <1429252989-4724-1-git-send-email-r.baldyga@samsung.com> In-Reply-To: <1429252989-4724-1-git-send-email-r.baldyga@samsung.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2506 Lines: 48 On 04/17/2015 02:43 AM, Robert Baldyga wrote: > This patch fixes problems with serial console break. When function > s3c64xx_serial_startup() was started while serial console has been working, > it caused lose of characters written to TX FIFO. This effect was particularly > observable with systemd, which closes serial port every time when it's > not currently needed, hence function s3c64xx_serial_startup() is called > quite often there. To fix this problem we avoid resetting TX FIFO if port is > used as serial console. > > Example of broken console log: > > [ 1086.7 Expecting device dev-ttySAC1.device... > [ 1086.[ OK ] Reached target Paths. > [ 1086.756416] s[ OK ] Reached target Swap. > [ 1086.776413] systemd[1]: Reached target Swap. > [ 1086.776642] systemd[1]: Starting Root Slice. > [ 5.53403[ OK ] Created slice Root Slice. > [ 5.548433] systemd[1]: Create[ OK ] Created slice User and Session Slice. > [ 5.568414] sys[ OK ] Listening on /dev/initctl Compatibility Named Pipe. > [ 5.588388] s[ OK ] Listening on Delayed Shutdown Socket. > [ 5.608376] sy[ OK ] Listening on Journal Socket (/dev/log). > [ 5.628361] [ OK ] Listening on udev Kernel Socket. > [ 5.648357] s[ OK ] Listening on udev Control Socket. > [ 5.668353] s[ OK ] Listening on Journal Socket. > [ 5.688366] systemd[1]: Listeni[ OK ] Created slice System Slice. > [ 5.708393] Mounting Temporary Directory... > [ 7139.067436] Starting prepare device daemon... > [ 7139.091726] sy Starting Generate environment from /etc/profile.d... > [ 5.792867] system Starting Create Static Device Nodes in /dev... > [ 7848.718 Mounting Debug File System... > [ 7848.7384 Mounting Configuration File System... > [ 5.852 Starting Apply Kernel Variables... > [ 5.8720 Starting Setup Virtual Console... > [ 7848.798 Starting udev Coldplug all Devices... > [ 7848.817 Starting Journal Service... > [ OK ] Started Journal Service. > [ 7848.854222] s[ OK ] Reached target Slices. > Starting Remount Root and Kernel File Systems... > [ OK ] Mounted Configuration File System. Reviewed-by: Peter Hurley -- 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/