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 0BC67C43334 for ; Tue, 21 Jun 2022 15:39:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352775AbiFUPjl (ORCPT ); Tue, 21 Jun 2022 11:39:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352791AbiFUPjf (ORCPT ); Tue, 21 Jun 2022 11:39:35 -0400 Received: from mx07-00178001.pphosted.com (mx07-00178001.pphosted.com [185.132.182.106]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A2C5E2B27A; Tue, 21 Jun 2022 08:39:34 -0700 (PDT) Received: from pps.filterd (m0241204.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 25LCe1mn006624; Tue, 21 Jun 2022 17:39:11 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=selector1; bh=UN5uEoUEwzsIoc43ELZbzUPrXzYLEx6ffknHGW66Lbo=; b=TkBwqxSba9+dCF/11e1Hh627aHD2f/KXTnIbTNaRSFSO0mGAXmCK+9pvrop8SvQrlZRg A5EjG0IjCSX8nEAh6GWaV0jBZZN8Gba5DDeg6xo1UPMewCOfZnTNJR0l6UueV27WnuQg UwSj9ZXzo6+TCvZzEqB2J+p9QwFwnESGrMRza0SpZO5s5gfhEPAL4Hpes5tD8QrfmDg6 HhDEFLY2n9qcdaNal8ICTmB+XwXV5WSG6ouhQXYgCMgdoSEoLDYVtmweomgxBorsy1Y2 PwkLdpL3rgmqa1uwvbgW4B0HAV/ONAIbZu+dHXbZIxfv+q6ZW/RQKnN5PmUIuo3QhyQV 8w== 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 3gua1n2tdy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 21 Jun 2022 17:39:11 +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 524BE10002A; Tue, 21 Jun 2022 17:39:10 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node2.st.com [10.75.129.70]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 4E32822F7A3; Tue, 21 Jun 2022 17:39:10 +0200 (CEST) Received: from [10.252.18.52] (10.75.127.118) by SHFDAG1NODE2.st.com (10.75.129.70) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2308.20; Tue, 21 Jun 2022 17:39:08 +0200 Message-ID: <9504e87e-78a5-36c5-2df9-c933c70a9103@foss.st.com> Date: Tue, 21 Jun 2022 17:39:08 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH 2/2] iio: adc: stm32-adc: disable adc before calibration Content-Language: en-US To: Olivier Moysan , Alexandre Torgue , Jonathan Cameron , Lars-Peter Clausen , Maxime Coquelin , Paul Cercueil , Wan Jiabing CC: , , , References: <20220620154738.801706-1-olivier.moysan@foss.st.com> <20220620154738.801706-3-olivier.moysan@foss.st.com> From: Fabrice Gasnier In-Reply-To: <20220620154738.801706-3-olivier.moysan@foss.st.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.75.127.118] X-ClientProxiedBy: GPXDAG2NODE5.st.com (10.75.127.69) To SHFDAG1NODE2.st.com (10.75.129.70) 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=2022-06-21_08,2022-06-21_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On 6/20/22 17:47, Olivier Moysan wrote: > The calibration is launched from prepare callback. > The ADC state when entering this function may be unknown as the > ADC may have been left enabled by boot stage. > One prerequisite for ADC calibration is to have ADC in disabled state. > If the calibration is started when ADC is still enabled, the behavior is > unpredictable, and the calibration may fail with a timeout error. > > Force ADC to disabled state in stm32h7_adc_selfcalib(). > ADC enabling is ensured by stm32h7_adc_enable() call, > before leaving prepare callback. > > Signed-off-by: Olivier Moysan Hi Olivier, You can add my: Reviewed-by: Fabrice Gasnier Thanks, Fabrice > --- > 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 80e333f65ddd..3985fe972892 100644 > --- a/drivers/iio/adc/stm32-adc.c > +++ b/drivers/iio/adc/stm32-adc.c > @@ -1019,6 +1019,9 @@ static int stm32h7_adc_selfcalib(struct iio_dev *indio_dev) > if (adc->cal.calibrated) > return true; > > + /* ADC must be disabled for calibration */ > + stm32h7_adc_disable(indio_dev); > + > /* > * Select calibration mode: > * - Offset calibration for single ended inputs