From patchwork Wed Sep 16 09:27:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Ardelean X-Patchwork-Id: 11779435 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 26CAF6CA for ; Wed, 16 Sep 2020 09:27:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1A05C22225 for ; Wed, 16 Sep 2020 09:27:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726612AbgIPJ1h (ORCPT ); Wed, 16 Sep 2020 05:27:37 -0400 Received: from mx0a-00128a01.pphosted.com ([148.163.135.77]:34742 "EHLO mx0a-00128a01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726369AbgIPJ1f (ORCPT ); Wed, 16 Sep 2020 05:27:35 -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 08G9PMJU000957; Wed, 16 Sep 2020 05:27:34 -0400 Received: from nwd2mta3.analog.com ([137.71.173.56]) by mx0a-00128a01.pphosted.com with ESMTP id 33k5p61ur9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 16 Sep 2020 05:27:34 -0400 Received: from ASHBMBX8.ad.analog.com (ashbmbx8.ad.analog.com [10.64.17.5]) by nwd2mta3.analog.com (8.14.7/8.14.7) with ESMTP id 08G9RX54028873 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=FAIL); Wed, 16 Sep 2020 05:27:33 -0400 Received: from ASHBMBX8.ad.analog.com (10.64.17.5) by ASHBMBX8.ad.analog.com (10.64.17.5) 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 05:27:41 -0400 Received: from zeus.spd.analog.com (10.66.68.11) by ASHBMBX8.ad.analog.com (10.64.17.5) with Microsoft SMTP Server id 15.1.1779.2 via Frontend Transport; Wed, 16 Sep 2020 05:27:41 -0400 Received: from localhost.localdomain ([10.48.65.12]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 08G9RTir022073; Wed, 16 Sep 2020 05:27:30 -0400 From: Alexandru Ardelean To: , CC: , Sergiu Cuciurean , Alexandru Ardelean Subject: [PATCH v2] iio: frequency: adf4350: Replace indio_dev->mlock with own device lock Date: Wed, 16 Sep 2020 12:27:31 +0300 Message-ID: <20200916092731.77220-1-alexandru.ardelean@analog.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200826064257.53475-1-alexandru.ardelean@analog.com> References: <20200826064257.53475-1-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=617 lowpriorityscore=0 impostorscore=0 bulkscore=0 adultscore=0 priorityscore=1501 mlxscore=0 phishscore=0 clxscore=1015 suspectscore=0 malwarescore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009160069 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org From: Sergiu Cuciurean As part of the general cleanup of indio_dev->mlock, this change replaces it with a local lock. The lock protect the state of the device from potential concurrent writes. The device is configured via a sequence of SPI writes, and this lock is meant to prevent the start of another sequence before another one has finished. This is part of a bigger cleanup. Link: https://lore.kernel.org/linux-iio/CA+U=Dsoo6YABe5ODLp+eFNPGFDjk5ZeQEceGkqjxXcVEhLWubw@mail.gmail.com/ Signed-off-by: Sergiu Cuciurean Signed-off-by: Alexandru Ardelean --- drivers/iio/frequency/adf4350.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/drivers/iio/frequency/adf4350.c b/drivers/iio/frequency/adf4350.c index 409c9c47161e..82c050a3899d 100644 --- a/drivers/iio/frequency/adf4350.c +++ b/drivers/iio/frequency/adf4350.c @@ -47,6 +47,13 @@ struct adf4350_state { unsigned long regs[6]; unsigned long regs_hw[6]; unsigned long long freq_req; + /* + * Lock to protect the state of the device from potential concurrent + * writes. The device is configured via a sequence of SPI writes, + * and this lock is meant to prevent the start of another sequence + * before another one has finished. + */ + struct mutex lock; /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. @@ -99,7 +106,7 @@ static int adf4350_reg_access(struct iio_dev *indio_dev, if (reg > ADF4350_REG5) return -EINVAL; - mutex_lock(&indio_dev->mlock); + mutex_lock(&st->lock); if (readval == NULL) { st->regs[reg] = writeval & ~(BIT(0) | BIT(1) | BIT(2)); ret = adf4350_sync_config(st); @@ -107,7 +114,7 @@ static int adf4350_reg_access(struct iio_dev *indio_dev, *readval = st->regs_hw[reg]; ret = 0; } - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&st->lock); return ret; } @@ -254,7 +261,7 @@ static ssize_t adf4350_write(struct iio_dev *indio_dev, if (ret) return ret; - mutex_lock(&indio_dev->mlock); + mutex_lock(&st->lock); switch ((u32)private) { case ADF4350_FREQ: ret = adf4350_set_freq(st, readin); @@ -295,7 +302,7 @@ static ssize_t adf4350_write(struct iio_dev *indio_dev, default: ret = -EINVAL; } - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&st->lock); return ret ? ret : len; } @@ -309,7 +316,7 @@ static ssize_t adf4350_read(struct iio_dev *indio_dev, unsigned long long val; int ret = 0; - mutex_lock(&indio_dev->mlock); + mutex_lock(&st->lock); switch ((u32)private) { case ADF4350_FREQ: val = (u64)((st->r0_int * st->r1_mod) + st->r0_fract) * @@ -338,7 +345,7 @@ static ssize_t adf4350_read(struct iio_dev *indio_dev, ret = -EINVAL; val = 0; } - mutex_unlock(&indio_dev->mlock); + mutex_unlock(&st->lock); return ret < 0 ? ret : sprintf(buf, "%llu\n", val); } @@ -539,6 +546,8 @@ static int adf4350_probe(struct spi_device *spi) indio_dev->channels = &adf4350_chan; indio_dev->num_channels = 1; + mutex_init(&st->lock); + st->chspc = pdata->channel_spacing; if (clk) { st->clk = clk;