From patchwork Mon Jun 20 15:47:37 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Olivier Moysan X-Patchwork-Id: 12887872 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CBE5BC43334 for ; Mon, 20 Jun 2022 15:49:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=2sSyV+aWr73t56P61gr8mi2tv+46xOex3NVxotMmDNc=; b=MMyQws9GZncQBM ALDazIikkK2t8h1WvOq8gVGsI31NiA7rHxeMW6gRQnveBfTV6x6Nmw0Y76ZMggAtVng6xiPw2bK80 mLM4gL/LOOUTmTAf2+0SA+FE8nX9YSMXVkUrX4hCKGvMKYMgJPtNx/kB747eI5ErTZ+26NkZqNQRK R/N4oVbmn6hMz5kc974bD2+Hqdhz9zBLfy0vEcfufqzzZQxzxXsWevUqtM08NjtN6aMmIouhzK+18 JUN9pQKQRH/pQM/hHBsC0EHq0JWWp4hzp+cIK1MA4hAzJ7GFem98KaMvHRjY73lLx4KmT8B5yjYlq JTslXCqis+YAArGysyhA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1o3Jdx-001JOI-1z; Mon, 20 Jun 2022 15:48:49 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93] helo=mx07-00178001.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1o3Jda-001JDf-RZ for linux-arm-kernel@lists.infradead.org; Mon, 20 Jun 2022 15:48:29 +0000 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 25KDwmdg019734; Mon, 20 Jun 2022 17:48:13 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=selector1; bh=FeTP5mpYBlwck24RxxFaADdquu3d8hoF9bo+/tGwtA8=; b=T04xrHjVLE3XGpmoZyScFR5nlgBdVk72P7oBI7vaQjdrWSy3tm8+mx1U1P6oK3G9uv/y 41A8zvfceliOrPBxUm2py2VIoqIfdE//ac5gKMyCzDUzai0pj9hzgOSF+YyA8yj+mjoe mS96LUV7k8UjS8z3SJeeiTol8NetRV7TpwvZykIZzxHEOpb5kT3f8rDmIs6vopr4onDj 31JPd90wd0nen3ZNTJRmvvLkc0Ahj+QJwkd4X+xY73PO0NrCrwiijZffqYyEqB5szmoN XPhLlQsFJijCYHzkLdB1YHNdQxOPmgMsc6cztl0B7vlRCnEoCKhfAHJWv4IU6ftQi824 Yw== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3gtp31tepn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 20 Jun 2022 17:48:13 +0200 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 117CE100034; Mon, 20 Jun 2022 17:48:13 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 0CCF122ECEF; Mon, 20 Jun 2022 17:48:13 +0200 (CEST) Received: from localhost (10.75.127.116) by SHFDAG1NODE1.st.com (10.75.129.69) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2308.20; Mon, 20 Jun 2022 17:48:12 +0200 From: Olivier Moysan To: Alexandre Torgue , Fabrice Gasnier , Jonathan Cameron , Lars-Peter Clausen , Maxime Coquelin , Olivier Moysan , Paul Cercueil , Wan Jiabing CC: , , , Subject: [PATCH 1/2] iio: adc: stm32-adc: make safe adc disable Date: Mon, 20 Jun 2022 17:47:37 +0200 Message-ID: <20220620154738.801706-2-olivier.moysan@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220620154738.801706-1-olivier.moysan@foss.st.com> References: <20220620154738.801706-1-olivier.moysan@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.116] X-ClientProxiedBy: GPXDAG2NODE5.st.com (10.75.127.69) To SHFDAG1NODE1.st.com (10.75.129.69) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.64.514 definitions=2022-06-20_05,2022-06-17_01,2022-02-23_01 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220620_084827_238342_5D29BC41 X-CRM114-Status: GOOD ( 13.87 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From ADC reference manual the software is allowed to write the control bit ADDIS of the ADC_CR register only if the ADC is enabled. Return immediately from stm32h7_adc_disable() if ADC is already disabled. Signed-off-by: Olivier Moysan Reviewed-by: Fabrice Gasnier --- drivers/iio/adc/stm32-adc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index a68ecbda6480..80e333f65ddd 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -876,6 +876,9 @@ static void stm32h7_adc_disable(struct iio_dev *indio_dev) int ret; u32 val; + if (!(stm32_adc_readl(adc, STM32H7_ADC_CR) & STM32H7_ADEN)) + return; + /* Disable ADC and wait until it's effectively disabled */ stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADDIS); ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val,