From patchwork Wed Jan 20 17:14:42 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Javier Martinez Canillas X-Patchwork-Id: 8073061 Return-Path: X-Original-To: patchwork-linux-samsung-soc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 0C27A9F96D for ; Wed, 20 Jan 2016 17:15:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4EE6D203B1 for ; Wed, 20 Jan 2016 17:15:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 62CA2204A7 for ; Wed, 20 Jan 2016 17:15:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964810AbcATRPo (ORCPT ); Wed, 20 Jan 2016 12:15:44 -0500 Received: from lists.s-osg.org ([54.187.51.154]:56018 "EHLO lists.s-osg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934916AbcATRPn (ORCPT ); Wed, 20 Jan 2016 12:15:43 -0500 Received: from sauron.localdomain (unknown [200.3.249.195]) by lists.s-osg.org (Postfix) with ESMTPSA id 7AE5F4632A; Wed, 20 Jan 2016 09:15:39 -0800 (PST) From: Javier Martinez Canillas To: linux-kernel@vger.kernel.org Cc: Kukjin Kim , rtc-linux@googlegroups.com, Chanwoo Choi , Alexandre Belloni , Krzysztof Kozlowski , Laxman Dewangan , linux-samsung-soc@vger.kernel.org, Javier Martinez Canillas Subject: [PATCH 2/8] rtc: max77686: Use usleep_range() instead of msleep() Date: Wed, 20 Jan 2016 14:14:42 -0300 Message-Id: <1453310088-29985-3-git-send-email-javier@osg.samsung.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1453310088-29985-1-git-send-email-javier@osg.samsung.com> References: <1453310088-29985-1-git-send-email-javier@osg.samsung.com> Sender: linux-samsung-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Documentation/timers/timers-howto.txt suggest to use usleep_range() instead of msleep() for small msec (1ms - 20ms) since msleep() will often sleep for 20ms for any value in that range. This is fine in this case since 16ms is the _minimum_ delay required by max77686 for an RTC update but by using usleep_range() instead of msleep(), the driver can support other RTC IP blocks with a shorter minium delay (i.e: in the range of usecs insted of msecs). Signed-off-by: Javier Martinez Canillas Reviewed-by: Krzysztof Kozlowski --- drivers/rtc/rtc-max77686.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-max77686.c b/drivers/rtc/rtc-max77686.c index 9599be257db4..ae4d61e7ce4b 100644 --- a/drivers/rtc/rtc-max77686.c +++ b/drivers/rtc/rtc-max77686.c @@ -41,7 +41,7 @@ #define ALARM_ENABLE_SHIFT 7 #define ALARM_ENABLE_MASK (1 << ALARM_ENABLE_SHIFT) -#define MAX77686_RTC_UPDATE_DELAY 16 +#define MAX77686_RTC_UPDATE_DELAY 16000 enum { RTC_SEC = 0, @@ -130,7 +130,8 @@ static int max77686_rtc_update(struct max77686_rtc_info *info, __func__, ret, data); else { /* Minimum 16ms delay required before RTC update. */ - msleep(MAX77686_RTC_UPDATE_DELAY); + usleep_range(MAX77686_RTC_UPDATE_DELAY, + MAX77686_RTC_UPDATE_DELAY * 2); } return ret;