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 X-Spam-Level: X-Spam-Status: No, score=-15.5 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE6BBC433E0 for ; Sat, 23 Jan 2021 15:27:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A005023331 for ; Sat, 23 Jan 2021 15:27:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726122AbhAWP1t (ORCPT ); Sat, 23 Jan 2021 10:27:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:45448 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726024AbhAWP1q (ORCPT ); Sat, 23 Jan 2021 10:27:46 -0500 Received: from archlinux (cpc108967-cmbg20-2-0-cust86.5-4.cable.virginm.net [81.101.6.87]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2610423331; Sat, 23 Jan 2021 15:27:03 +0000 (UTC) Date: Sat, 23 Jan 2021 15:26:59 +0000 From: Jonathan Cameron To: Tom Rix Cc: Guoqing Chi , martin.blumenstingl@googlemail.com, linux-kernel@vger.kernel.org, chiguoqing@yulong.com, huyue2@yulong.com, zhangwen@yulong.com, linux-iio@vger.kernel.org Subject: Re: [PATCH v2] iio: imu: bmi160: add mutex_lock for avoiding race Message-ID: <20210123152659.563cddeb@archlinux> In-Reply-To: <9c9333cb-bd6c-0f29-f35b-7592f457c746@redhat.com> References: <20210119112211.26404-1-chi962464zy@163.com> <20210120094802.00001fee@163.com> <9c9333cb-bd6c-0f29-f35b-7592f457c746@redhat.com> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; 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-iio@vger.kernel.org On Wed, 20 Jan 2021 07:06:23 -0800 Tom Rix wrote: > On 1/19/21 5:48 PM, Guoqing Chi wrote: > > On Tue, 19 Jan 2021 06:54:45 -0800 > > Tom Rix wrote: > > > >> On 1/19/21 3:22 AM, Guoqing Chi wrote: > >>> From: chiguoqing > >>> > >>> Adding mutex_lock, when read and write reg need to use this lock to > >>> avoid race. > >>> > >>> Signed-off-by: Guoqing Chi > >>> --- > >>> v2:Follow write function to fix read function. > >>> Adding mutex init in core probe function. > >>> Adding break in switch case at read and write function. > >>> > >>> drivers/iio/imu/bmi160/bmi160.h | 2 ++ > >>> drivers/iio/imu/bmi160/bmi160_core.c | 34 > >>> +++++++++++++++++++--------- 2 files changed, 25 insertions(+), 11 > >>> deletions(-) > >>> > >>> diff --git a/drivers/iio/imu/bmi160/bmi160.h > >>> b/drivers/iio/imu/bmi160/bmi160.h index 32c2ea2d7112..0c189a8b5b53 > >>> 100644 --- a/drivers/iio/imu/bmi160/bmi160.h > >>> +++ b/drivers/iio/imu/bmi160/bmi160.h > >>> @@ -3,9 +3,11 @@ > >>> #define BMI160_H_ > >>> > >>> #include > >>> +#include > >>> #include > >>> > >>> struct bmi160_data { > >>> + struct mutex lock; > >>> struct regmap *regmap; > >>> struct iio_trigger *trig; > >>> struct regulator_bulk_data supplies[2]; > >>> diff --git a/drivers/iio/imu/bmi160/bmi160_core.c > >>> b/drivers/iio/imu/bmi160/bmi160_core.c index > >>> 290b5ef83f77..e303378f4841 100644 --- > >>> a/drivers/iio/imu/bmi160/bmi160_core.c +++ > >>> b/drivers/iio/imu/bmi160/bmi160_core.c @@ -452,26 +452,32 @@ static > >>> int bmi160_read_raw(struct iio_dev *indio_dev, int ret; > >>> struct bmi160_data *data = iio_priv(indio_dev); > >>> > >>> + mutex_lock(&data->lock); > >>> switch (mask) { > >>> case IIO_CHAN_INFO_RAW: > >>> ret = bmi160_get_data(data, chan->type, > >>> chan->channel2, val); > >>> - if (ret) > >>> - return ret; > >>> - return IIO_VAL_INT; > >>> + if (!ret) > >>> + ret = IIO_VAL_INT; > >>> + break; > >>> case IIO_CHAN_INFO_SCALE: > >>> *val = 0; > >>> ret = bmi160_get_scale(data, > >>> bmi160_to_sensor(chan->type), > >>> val2); > >>> - return ret ? ret : IIO_VAL_INT_PLUS_MICRO; > >>> + if (!ret) > >>> + ret = IIO_VAL_INT_PLUS_MICRO; > >> Looking better, another question.. > >> > >> Why does the write() function return the results directly while the > >> read() function > >> > >> translates them to other values ? > >> > >> Tom > > It is original design in this driver. In order to > > differentiate raw to scale and SAMP_FREQ, while the scale and SAMP_FREQ > > are needless. I think log information can be added for this purpose, > > and return results directly. > > It is not change the return values for my modify.It's best to keep the > > original design.Is that all right? > > Ok. > > Reviewed-by: Tom Rix Hi Guoqing Chi, For some reason the original patch email (start of this thread) never made it to my inbox or indeed the archive at lore.kernel.org. Please resend (picking up Tom's reviewed by) and make sure to cc linux-iio@vger.kernel.org + jic23@kernel.org Then check if they make it to lore.kernel.org as that should highlight any issues where it is getting blocked etc. Thanks, Jonathan > > > Guoqing Chi > >>> + break; > >>> case IIO_CHAN_INFO_SAMP_FREQ: > >>> ret = bmi160_get_odr(data, > >>> bmi160_to_sensor(chan->type), val, val2); > >>> - return ret ? ret : IIO_VAL_INT_PLUS_MICRO; > >>> + if (!ret) > >>> + ret = IIO_VAL_INT_PLUS_MICRO; > >>> + break; > >>> default: > >>> - return -EINVAL; > >>> + ret = -EINVAL; > >>> } > >>> + mutex_unlock(&data->lock); > >>> > >>> - return 0; > >>> + return ret; > >>> } > >>> > >>> static int bmi160_write_raw(struct iio_dev *indio_dev, > >>> @@ -479,19 +485,24 @@ static int bmi160_write_raw(struct iio_dev > >>> *indio_dev, int val, int val2, long mask) > >>> { > >>> struct bmi160_data *data = iio_priv(indio_dev); > >>> + int result; > >>> > >>> + mutex_lock(&data->lock); > >>> switch (mask) { > >>> case IIO_CHAN_INFO_SCALE: > >>> - return bmi160_set_scale(data, > >>> + result = bmi160_set_scale(data, > >>> bmi160_to_sensor(chan->type), > >>> val2); > >>> + break; > >>> case IIO_CHAN_INFO_SAMP_FREQ: > >>> - return bmi160_set_odr(data, > >>> bmi160_to_sensor(chan->type), > >>> + result = bmi160_set_odr(data, > >>> bmi160_to_sensor(chan->type), val, val2); > >>> + break; > >>> default: > >>> - return -EINVAL; > >>> + result = -EINVAL; > >>> } > >>> + mutex_unlock(&data->lock); > >>> > >>> - return 0; > >>> + return result; > >>> } > >>> > >>> static > >>> @@ -838,6 +849,7 @@ int bmi160_core_probe(struct device *dev, > >>> struct regmap *regmap, return -ENOMEM; > >>> > >>> data = iio_priv(indio_dev); > >>> + mutex_init(&data->lock); > >>> dev_set_drvdata(dev, indio_dev); > >>> data->regmap = regmap; > >>> >