From patchwork Wed Sep 16 09:31:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Ardelean X-Patchwork-Id: 11779453 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 290A36CA for ; Wed, 16 Sep 2020 09:32:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19681221E5 for ; Wed, 16 Sep 2020 09:32:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726707AbgIPJbv (ORCPT ); Wed, 16 Sep 2020 05:31:51 -0400 Received: from mx0a-00128a01.pphosted.com ([148.163.135.77]:46876 "EHLO mx0a-00128a01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726688AbgIPJbi (ORCPT ); Wed, 16 Sep 2020 05:31:38 -0400 Received: from pps.filterd (m0167088.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 08G9PWrX012821; Wed, 16 Sep 2020 05:31:31 -0400 Received: from nwd2mta4.analog.com ([137.71.173.58]) by mx0a-00128a01.pphosted.com with ESMTP id 33k5p61v2p-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 16 Sep 2020 05:31:30 -0400 Received: from SCSQMBX11.ad.analog.com (scsqmbx11.ad.analog.com [10.77.17.10]) by nwd2mta4.analog.com (8.14.7/8.14.7) with ESMTP id 08G9VT0n050743 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=FAIL); Wed, 16 Sep 2020 05:31:29 -0400 Received: from SCSQMBX10.ad.analog.com (10.77.17.5) by SCSQMBX11.ad.analog.com (10.77.17.10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1779.2; Wed, 16 Sep 2020 02:31:36 -0700 Received: from zeus.spd.analog.com (10.66.68.11) by SCSQMBX10.ad.analog.com (10.77.17.5) with Microsoft SMTP Server id 15.1.1779.2 via Frontend Transport; Wed, 16 Sep 2020 02:31:36 -0700 Received: from localhost.localdomain ([10.48.65.12]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 08G9VL9d022209; Wed, 16 Sep 2020 05:31:22 -0400 From: Alexandru Ardelean To: , , , CC: , , , Sergiu Cuciurean , Alexandru Ardelean Subject: [PATCH v2] iio: adc: exynos_adc: Replace indio_dev->mlock with own device lock Date: Wed, 16 Sep 2020 12:31:23 +0300 Message-ID: <20200916093123.78954-1-alexandru.ardelean@analog.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200826132203.236748-1-alexandru.ardelean@analog.com> References: <20200826132203.236748-1-alexandru.ardelean@analog.com> MIME-Version: 1.0 X-ADIRoutedOnPrem: True X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-09-16_02:2020-09-15,2020-09-16 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=949 lowpriorityscore=0 impostorscore=0 bulkscore=0 adultscore=0 priorityscore=1501 mlxscore=0 phishscore=0 clxscore=1011 suspectscore=0 malwarescore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009160069 Sender: linux-samsung-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org From: Sergiu Cuciurean As part of the general cleanup of indio_dev->mlock, this change replaces it with a local lock, to protect potential concurrent access to the completion callback during a conversion. This is part of a bigger cleanup. Link: https://lore.kernel.org/linux-iio/CA+U=Dsoo6YABe5ODLp+eFNPGFDjk5ZeQEceGkqjxXcVEhLWubw@mail.gmail.com/ Reviewed-by: Krzysztof Kozlowski Signed-off-by: Sergiu Cuciurean Signed-off-by: Alexandru Ardelean --- drivers/iio/adc/exynos_adc.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c index 20477b249f2a..99f4404e9fd1 100644 --- a/drivers/iio/adc/exynos_adc.c +++ b/drivers/iio/adc/exynos_adc.c @@ -138,6 +138,16 @@ struct exynos_adc { bool read_ts; u32 ts_x; u32 ts_y; + + /* + * Lock to protect from potential concurrent access to the + * completion callback during a manual conversion. For this driver + * a wait-callback is used to wait for the conversion result, + * so in the meantime no other read request (or conversion start) + * must be performed, otherwise it would interfere with the + * current conversion result. + */ + struct mutex lock; }; struct exynos_adc_data { @@ -542,7 +552,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev, return -EINVAL; } - mutex_lock(&indio_dev->mlock); + mutex_lock(&info->lock); reinit_completion(&info->completion); /* Select the channel to be used and Trigger conversion */ @@ -562,7 +572,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev, ret = IIO_VAL_INT; } - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&info->lock); return ret; } @@ -573,7 +583,7 @@ static int exynos_read_s3c64xx_ts(struct iio_dev *indio_dev, int *x, int *y) unsigned long timeout; int ret; - mutex_lock(&indio_dev->mlock); + mutex_lock(&info->lock); info->read_ts = true; reinit_completion(&info->completion); @@ -598,7 +608,7 @@ static int exynos_read_s3c64xx_ts(struct iio_dev *indio_dev, int *x, int *y) } info->read_ts = false; - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&info->lock); return ret; } @@ -868,6 +878,8 @@ static int exynos_adc_probe(struct platform_device *pdev) indio_dev->channels = exynos_adc_iio_channels; indio_dev->num_channels = info->data->num_channels; + mutex_init(&info->lock); + ret = request_irq(info->irq, exynos_adc_isr, 0, dev_name(&pdev->dev), info); if (ret < 0) {