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 06F6CC433EF for ; Mon, 13 Jun 2022 13:11:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357541AbiFMNL3 (ORCPT ); Mon, 13 Jun 2022 09:11:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359477AbiFMNJ5 (ORCPT ); Mon, 13 Jun 2022 09:09:57 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87F0E20187; Mon, 13 Jun 2022 04:20:53 -0700 (PDT) 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 39734B80EAB; Mon, 13 Jun 2022 11:20:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9E636C34114; Mon, 13 Jun 2022 11:20:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655119251; bh=PD9e8Q2ln03IrdWmHwh9Oq+TnF2LvQdLrZsDfZ77aVg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BSN6qTyXkkYlcfjDp2UgET03Tgk2P7ulC/JCICbx3D1b8mTOCVHAYSjZ5OBIJo4/3 EUAgNvBJpp5bUnpyaVRpVL+tJJl83s//5EeeOueRvuiQqWxQiKFSTquKBCd+rLbfat vXl8BBN0fEwH6PlmDBu/db6yzx+oUtvUhf3gSWX0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jonathan Cameron , Denis Ciocca , Miquel Raynal , Jonathan Cameron , Sasha Levin Subject: [PATCH 5.15 167/247] iio: st_sensors: Add a local lock for protecting odr Date: Mon, 13 Jun 2022 12:11:09 +0200 Message-Id: <20220613094928.023172711@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094922.843438024@linuxfoundation.org> References: <20220613094922.843438024@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Miquel Raynal [ Upstream commit 474010127e2505fc463236470908e1ff5ddb3578 ] Right now the (framework) mlock lock is (ab)used for multiple purposes: 1- protecting concurrent accesses over the odr local cache 2- avoid changing samplig frequency whilst buffer is running Let's start by handling situation #1 with a local lock. Suggested-by: Jonathan Cameron Cc: Denis Ciocca Signed-off-by: Miquel Raynal Link: https://lore.kernel.org/r/20220207143840.707510-7-miquel.raynal@bootlin.com Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- .../iio/common/st_sensors/st_sensors_core.c | 24 ++++++++++++++----- include/linux/iio/common/st_sensors.h | 3 +++ 2 files changed, 21 insertions(+), 6 deletions(-) diff --git a/drivers/iio/common/st_sensors/st_sensors_core.c b/drivers/iio/common/st_sensors/st_sensors_core.c index 0bbb090b108c..aff981551617 100644 --- a/drivers/iio/common/st_sensors/st_sensors_core.c +++ b/drivers/iio/common/st_sensors/st_sensors_core.c @@ -71,16 +71,18 @@ static int st_sensors_match_odr(struct st_sensor_settings *sensor_settings, int st_sensors_set_odr(struct iio_dev *indio_dev, unsigned int odr) { - int err; + int err = 0; struct st_sensor_odr_avl odr_out = {0, 0}; struct st_sensor_data *sdata = iio_priv(indio_dev); + mutex_lock(&sdata->odr_lock); + if (!sdata->sensor_settings->odr.mask) - return 0; + goto unlock_mutex; err = st_sensors_match_odr(sdata->sensor_settings, odr, &odr_out); if (err < 0) - goto st_sensors_match_odr_error; + goto unlock_mutex; if ((sdata->sensor_settings->odr.addr == sdata->sensor_settings->pw.addr) && @@ -103,7 +105,9 @@ int st_sensors_set_odr(struct iio_dev *indio_dev, unsigned int odr) if (err >= 0) sdata->odr = odr_out.hz; -st_sensors_match_odr_error: +unlock_mutex: + mutex_unlock(&sdata->odr_lock); + return err; } EXPORT_SYMBOL(st_sensors_set_odr); @@ -365,6 +369,8 @@ int st_sensors_init_sensor(struct iio_dev *indio_dev, struct st_sensors_platform_data *of_pdata; int err = 0; + mutex_init(&sdata->odr_lock); + /* If OF/DT pdata exists, it will take precedence of anything else */ of_pdata = st_sensors_dev_probe(indio_dev->dev.parent, pdata); if (IS_ERR(of_pdata)) @@ -558,18 +564,24 @@ int st_sensors_read_info_raw(struct iio_dev *indio_dev, err = -EBUSY; goto out; } else { + mutex_lock(&sdata->odr_lock); err = st_sensors_set_enable(indio_dev, true); - if (err < 0) + if (err < 0) { + mutex_unlock(&sdata->odr_lock); goto out; + } msleep((sdata->sensor_settings->bootime * 1000) / sdata->odr); err = st_sensors_read_axis_data(indio_dev, ch, val); - if (err < 0) + if (err < 0) { + mutex_unlock(&sdata->odr_lock); goto out; + } *val = *val >> ch->scan_type.shift; err = st_sensors_set_enable(indio_dev, false); + mutex_unlock(&sdata->odr_lock); } out: mutex_unlock(&indio_dev->mlock); diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h index 8bdbaf3f3796..69f4a1f6b536 100644 --- a/include/linux/iio/common/st_sensors.h +++ b/include/linux/iio/common/st_sensors.h @@ -238,6 +238,7 @@ struct st_sensor_settings { * @hw_irq_trigger: if we're using the hardware interrupt on the sensor. * @hw_timestamp: Latest timestamp from the interrupt handler, when in use. * @buffer_data: Data used by buffer part. + * @odr_lock: Local lock for preventing concurrent ODR accesses/changes */ struct st_sensor_data { struct device *dev; @@ -263,6 +264,8 @@ struct st_sensor_data { s64 hw_timestamp; char buffer_data[ST_SENSORS_MAX_BUFFER_SIZE] ____cacheline_aligned; + + struct mutex odr_lock; }; #ifdef CONFIG_IIO_BUFFER -- 2.35.1