Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932417AbbHXHTL (ORCPT ); Mon, 24 Aug 2015 03:19:11 -0400 Received: from down.free-electrons.com ([37.187.137.238]:53690 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751980AbbHXHTJ (ORCPT ); Mon, 24 Aug 2015 03:19:09 -0400 Date: Mon, 24 Aug 2015 09:19:07 +0200 From: Alexandre Belloni To: Joonyoung Shim Cc: rtc-linux@googlegroups.com, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, a.zummo@towertech.it, sbkim73@samsung.com, k.kozlowski@samsung.com Subject: Re: [PATCH v2] rtc: s5m: fix to update ctrl register Message-ID: <20150824071907.GD13155@piout.net> References: <1440150221-2609-1-git-send-email-jy0922.shim@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1440150221-2609-1-git-send-email-jy0922.shim@samsung.com> 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: 1691 Lines: 40 On 21/08/2015 at 18:43:41 +0900, Joonyoung Shim wrote : > According to datasheet, the S2MPS13X and S2MPS14X should update write > buffer via setting WUDR bit to high after ctrl register is written. > > If not, ALARM interrupt of rtc-s5m doesn't happen first time when i use > tools/testing/selftests/timers/rtctest.c test program and hour format is > used to 12 hour mode in Odroid-XU3 board. > > One more issue is the RTC doesn't keep time on Odroid-XU3 board when i > turn on board after power off even if RTC battery is connected. It can > be solved as setting WUDR & RUDR bits to high at the same time after > RTC_CTRL register is written. It's same with condition of only writing > ALARM registers, so this is for only S2MPS14 and we should set WUDR & > A_UDR bits to high on S2MPS13. > > I can't find any reasonable description about this like fix from > datasheet, but can find similar codes from rtc driver source of > hardkernel kernel and vender kernel. > > Signed-off-by: Joonyoung Shim > Cc: # v3.16 > --- > Changelog for v2: > - update commit description and code to fix time keeping problem > - update the stable tag with the kernel version > > drivers/rtc/rtc-s5m.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > Applied, thanks. I fixed the small typo. -- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- 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/