From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA559C433F5 for ; Sun, 13 Feb 2022 17:53:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237564AbiBMRxJ (ORCPT ); Sun, 13 Feb 2022 12:53:09 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:51212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230120AbiBMRxH (ORCPT ); Sun, 13 Feb 2022 12:53:07 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DDC475A584; Sun, 13 Feb 2022 09:53:01 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 8A2CFB80B0E; Sun, 13 Feb 2022 17:53:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CF9FBC004E1; Sun, 13 Feb 2022 17:52:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1644774779; bh=kPHxeTgcg9NmBIAzq6Zcpzz0ekEcpp+pRXOIDMqRzhw=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Yfg7avbQeAvZoIIXzV24s1tWEfcF5XFVC1hDW6+V6Nar/TQvPUDFqZlOCcJwIgo6L cM3Z/v2t2Lwfdx9IdyKMCsHNuFgFxqEAH/2c3/KdG312xiW3rqqUv85sRu9DZnGHYw 2ot7Wi8AzlEBWmjQ0TKLrmZB92cWw54VpAMG9cHBEt4ybj427j5Xr1e/2aXkiieRFm Vjrj5s2RGNi3cAnse4/ZgPC3b/qiP7d5BT2RU+se5gzybbZ4CaEmmxCI5fsBQgM6tG gccd7RbCaZQ4wJNwZE4AqXXPvymW19SPRqtTqM3h/T+mBxeAq3udK5nxaWZ4HlWSqG P0wVCTVjCBmQw== Date: Sun, 13 Feb 2022 17:59:40 +0000 From: Jonathan Cameron To: Qing Wang Cc: Jyoti Bhayana , Lars-Peter Clausen , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] iio: use div64_u64() instead of do_div() Message-ID: <20220213175940.1066f5a8@jic23-huawei> In-Reply-To: <1644395873-3937-1-git-send-email-wangqing@vivo.com> References: <1644395873-3937-1-git-send-email-wangqing@vivo.com> X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 9 Feb 2022 00:37:53 -0800 Qing Wang wrote: > From: Wang Qing > > do_div() does a 64-by-32 division. > When the divisor is u64, do_div() truncates it to 32 bits, this means it > can test non-zero and be truncated to zero for division. > > fix do_div.cocci warning: > do_div() does a 64-by-32 division, please consider using div64_u64 instead. > > Signed-off-by: Wang Qing These look correct to me. Jyoti, please could give these a sanity check? Thanks, Jonathan > --- > drivers/iio/common/scmi_sensors/scmi_iio.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/iio/common/scmi_sensors/scmi_iio.c b/drivers/iio/common/scmi_sensors/scmi_iio.c > index d538bf3..d6df5da > --- a/drivers/iio/common/scmi_sensors/scmi_iio.c > +++ b/drivers/iio/common/scmi_sensors/scmi_iio.c > @@ -160,7 +160,7 @@ static int scmi_iio_set_odr_val(struct iio_dev *iio_dev, int val, int val2) > mult = scnprintf(buf, sizeof(buf), "%llu", sf) - 1; > > sec = int_pow(10, mult) * UHZ_PER_HZ; > - do_div(sec, uHz); > + div64_u64(sec, uHz); > if (sec == 0) { > dev_err(&iio_dev->dev, > "Trying to set invalid sensor update value for sensor %s", > @@ -237,10 +237,10 @@ static void convert_ns_to_freq(u64 interval_ns, u64 *hz, u64 *uhz) > u64 rem, freq; > > freq = NSEC_PER_SEC; > - rem = do_div(freq, interval_ns); > + rem = div64_u64(freq, interval_ns); > *hz = freq; > *uhz = rem * 1000000UL; > - do_div(*uhz, interval_ns); > + div64_u64(*uhz, interval_ns); > } > > static int scmi_iio_get_odr_val(struct iio_dev *iio_dev, int *val, int *val2) > @@ -266,7 +266,7 @@ static int scmi_iio_get_odr_val(struct iio_dev *iio_dev, int *val, int *val2) > mult = SCMI_SENS_CFG_GET_UPDATE_EXP(sensor_config); > if (mult < 0) { > sensor_interval_mult = int_pow(10, abs(mult)); > - do_div(sensor_update_interval, sensor_interval_mult); > + div64_u64(sensor_update_interval, sensor_interval_mult); > } else { > sensor_interval_mult = int_pow(10, mult); > sensor_update_interval = > @@ -500,7 +500,7 @@ static u64 scmi_iio_convert_interval_to_ns(u32 val) > mult = SCMI_SENS_INTVL_GET_EXP(val); > if (mult < 0) { > sensor_interval_mult = int_pow(10, abs(mult)); > - do_div(sensor_update_interval, sensor_interval_mult); > + div64_u64(sensor_update_interval, sensor_interval_mult); > } else { > sensor_interval_mult = int_pow(10, mult); > sensor_update_interval =