From patchwork Thu Nov 18 03:25:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Li X-Patchwork-Id: 1556465 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-rtc-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by bilbo.ozlabs.org (Postfix) with ESMTP id 4HvlYr3Qfwz9sXM for ; Thu, 18 Nov 2021 14:25:52 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241615AbhKRD2u (ORCPT ); Wed, 17 Nov 2021 22:28:50 -0500 Received: from out30-130.freemail.mail.aliyun.com ([115.124.30.130]:42397 "EHLO out30-130.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241600AbhKRD2t (ORCPT ); Wed, 17 Nov 2021 22:28:49 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R561e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04357;MF=yang.lee@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0Ux6f13A_1637205946; Received: from j63c13417.sqa.eu95.tbsite.net(mailfrom:yang.lee@linux.alibaba.com fp:SMTPD_---0Ux6f13A_1637205946) by smtp.aliyun-inc.com(127.0.0.1); Thu, 18 Nov 2021 11:25:47 +0800 From: Yang Li To: patrice.chotard@foss.st.com Cc: a.zummo@towertech.it, alexandre.belloni@bootlin.com, linux-arm-kernel@lists.infradead.org, linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org, Yang Li Subject: [PATCH -next] rtc: st-lpc: Use div64_ul instead of do_div Date: Thu, 18 Nov 2021 11:25:41 +0800 Message-Id: <1637205941-26223-1-git-send-email-yang.lee@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org do_div() does a 64-by-32 division. Here the divisor is an unsigned long which on some platforms is 64 bit wide. So use div64_ul instead of do_div to avoid a possible truncation. Eliminate the following coccicheck warnings: ./drivers/rtc/rtc-st-lpc.c:96:1-7: WARNING: do_div() does a 64-by-32 division, please consider using div64_ul instead. ./drivers/rtc/rtc-st-lpc.c:251:1-7: WARNING: do_div() does a 64-by-32 division, please consider using div64_ul instead. Reported-by: Abaci Robot Signed-off-by: Yang Li --- drivers/rtc/rtc-st-lpc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-st-lpc.c b/drivers/rtc/rtc-st-lpc.c index bdb20f6..b6e169b 100644 --- a/drivers/rtc/rtc-st-lpc.c +++ b/drivers/rtc/rtc-st-lpc.c @@ -93,7 +93,7 @@ static int st_rtc_read_time(struct device *dev, struct rtc_time *tm) spin_unlock_irqrestore(&rtc->lock, flags); lpt = ((unsigned long long)lpt_msb << 32) | lpt_lsb; - do_div(lpt, rtc->clkrate); + lpt = div64_ul(lpt, rtc->clkrate); rtc_time64_to_tm(lpt, tm); return 0; @@ -248,7 +248,8 @@ static int st_rtc_probe(struct platform_device *pdev) rtc->rtc_dev->ops = &st_rtc_ops; rtc->rtc_dev->range_max = U64_MAX; - do_div(rtc->rtc_dev->range_max, rtc->clkrate); + rtc->rtc_dev->range_max = div64_ul(rtc->rtc_dev->range_max, + rtc->clkrate); ret = devm_rtc_register_device(rtc->rtc_dev); if (ret) {