From patchwork Mon Sep 18 10:05:30 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 9956263 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0721F601E9 for ; Mon, 18 Sep 2017 10:08:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E9EBA2841D for ; Mon, 18 Sep 2017 10:08:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DC63128B2F; Mon, 18 Sep 2017 10:08:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C05EF2841D for ; Mon, 18 Sep 2017 10:07:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=C7PVC/viLtcuPMp/wqqTKfX6htvi17voraIsEqjSZvM=; b=BXJVNPxX+/Fuom nJBdqzo3vdLFyAg9FeWt9whEF7fqoQ6Yqa0yqZcqSc41ZgglOXJB0uxAr2v5XvN9M/64xoth6HaD4 ZfeEvlTM+a32SEvyYS/kZKiOFCdgL1ENDNG1h5lWV69brDhMnsguKwdNosL0MYn999SYOAnUK/5Jf rx5kEjnCBiRQ4zgXP9swN38k+Ewdm6F3hw/dkVBFe5YPpPtvCdjyzSTyUQToCpXGoMnSjWfEocZDc 0522IFH3f14NfoA2Ja2vwdZZeUaoPMrnUzuQpXkuwGP9YwztDdZSCsz8kxA82VvWwImDvgfrqe47s SUfnNiEXozxAwCfVu3Tw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1dtsy2-0004Ue-GV; Mon, 18 Sep 2017 10:07:54 +0000 Received: from mx07-00178001.pphosted.com ([62.209.51.94]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1dtswf-0003Ea-4F for linux-arm-kernel@lists.infradead.org; Mon, 18 Sep 2017 10:06:33 +0000 Received: from pps.filterd (m0046668.ppops.net [127.0.0.1]) by mx07-.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v8IA4An8000865; Mon, 18 Sep 2017 12:06:02 +0200 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 2d20x02qen-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 18 Sep 2017 12:06:02 +0200 Received: from zeta.dmz-eu.st.com (zeta.dmz-eu.st.com [164.129.230.9]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 4B7E731; Mon, 18 Sep 2017 10:06:01 +0000 (GMT) Received: from Webmail-eu.st.com (sfhdag5node3.st.com [10.75.127.15]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 15A3C16B9; Mon, 18 Sep 2017 10:06:01 +0000 (GMT) Received: from localhost (10.75.127.48) by SFHDAG5NODE3.st.com (10.75.127.15) with Microsoft SMTP Server (TLS) id 15.0.1178.4; Mon, 18 Sep 2017 12:06:00 +0200 From: Fabrice Gasnier To: Subject: [PATCH 1/3] iio: trigger: stm32-timer: preset shouldn't be buffered Date: Mon, 18 Sep 2017 12:05:30 +0200 Message-ID: <1505729132-1369-2-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1505729132-1369-1-git-send-email-fabrice.gasnier@st.com> References: <1505729132-1369-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.48] X-ClientProxiedBy: SFHDAG4NODE1.st.com (10.75.127.10) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-09-18_02:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170918_030629_603711_F3BE8264 X-CRM114-Status: UNSURE ( 8.36 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: benjamin.gaignard@linaro.org, lars@metafoo.de, benjamin.gaignard@st.com, linux-iio@vger.kernel.org, pmeerw@pmeerw.net, linux-kernel@vger.kernel.org, mcoquelin.stm32@gmail.com, knaack.h@gmx.de, fabrice.gasnier@st.com, linux-arm-kernel@lists.infradead.org, alexandre.torgue@st.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Currently, setting preset value (ARR) will update directly 'Auto reload value' only on 1st write access. But then, ARPE is set. This makes ARR a shadow register. Preset value should be updated upon each write request: ensure ARPE is 0. This fixes successive writes to preset attribute. Fixes: 4adec7da0536 ("iio: stm32 trigger: Add quadrature encoder device") Signed-off-by: Fabrice Gasnier --- drivers/iio/trigger/stm32-timer-trigger.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c index 9b90534..34cc25b 100644 --- a/drivers/iio/trigger/stm32-timer-trigger.c +++ b/drivers/iio/trigger/stm32-timer-trigger.c @@ -715,8 +715,9 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev, if (ret) return ret; + /* TIMx_ARR register shouldn't be buffered (ARPE=0) */ + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0); regmap_write(priv->regmap, TIM_ARR, preset); - regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, TIM_CR1_ARPE); return len; }