From patchwork Fri Feb 23 12:51:01 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabrice Gasnier X-Patchwork-Id: 10237599 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 EE669602DC for ; Fri, 23 Feb 2018 12:53:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DD8512955E for ; Fri, 23 Feb 2018 12:53:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D1E7F2957B; Fri, 23 Feb 2018 12:53:59 +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=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 5364A2955E for ; Fri, 23 Feb 2018 12:53:59 +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=OKcsswdvjsrLL3zELZwhm+S2NOa0NabEB/cfKUWcKFk=; b=MgbZtauLrhc6tM hTaNum4ozpHk+O9P3Z3T/kZB4z5rrwf84fhTwmE/8N0Dh/wica7Dm+zskgfoPkrh0XfsXrlv8oPUG mdXo1P1Vf8K8ohakQDnVH7x4ru75Y4xEaRXcZQG0xC834N8U9b028NL4DEfK2jg35/CeNa+lXU4ud t88KwX1X6YPh8RZPQLouLAM9+PWRq1vYCWLTcc3I+huNoXX3ifKXyK4O+vSSNqks4RvjE0wFvG2wr oW+nlFtF8xcrd+TdaEf+Eo1HlkhraSfy5YynkeDHZg+i9/4xWa0VoiGTQdvgWcFojYaledw42tfss UxIZXnlS/O4PWhk3en7A==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1epCrF-0000DV-LT; Fri, 23 Feb 2018 12:53:49 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93] helo=mx07-00178001.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.89 #1 (Red Hat Linux)) id 1epCp7-0007cR-Qx for linux-arm-kernel@lists.infradead.org; Fri, 23 Feb 2018 12:51:41 +0000 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx08-.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id w1NCmetj017163; Fri, 23 Feb 2018 13:51:24 +0100 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx08-00178001.pphosted.com with ESMTP id 2g9bqd2227-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Fri, 23 Feb 2018 13:51:23 +0100 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 6ABF031; Fri, 23 Feb 2018 12:51:23 +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 52F554DB7; Fri, 23 Feb 2018 12:51:23 +0000 (GMT) Received: from localhost (10.75.127.45) by SFHDAG5NODE3.st.com (10.75.127.15) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Fri, 23 Feb 2018 13:51:22 +0100 From: Fabrice Gasnier To: Subject: [PATCH 7/7] iio: adc: stm32-dfsdm: add check on spi-max-frequency Date: Fri, 23 Feb 2018 13:51:01 +0100 Message-ID: <1519390261-25453-8-git-send-email-fabrice.gasnier@st.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1519390261-25453-1-git-send-email-fabrice.gasnier@st.com> References: <1519390261-25453-1-git-send-email-fabrice.gasnier@st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.45] X-ClientProxiedBy: SFHDAG3NODE3.st.com (10.75.127.9) To SFHDAG5NODE3.st.com (10.75.127.15) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2018-02-23_04:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180223_045138_216080_1714EAE6 X-CRM114-Status: UNSURE ( 9.85 ) 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, alexandre.torgue@st.com, linux-iio@vger.kernel.org, pmeerw@pmeerw.net, arnaud.pouliquen@st.com, linux-kernel@vger.kernel.org, mcoquelin.stm32@gmail.com, knaack.h@gmx.de, fabrice.gasnier@st.com, linux-arm-kernel@lists.infradead.org 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 spi-max-frequency is requested for SPI master mode (only), to tune output clock. It may happen requested frequency isn't reachable. Add explicit check, so probe fails with error in this case. Otherwise, output clock may simply be silently turned off (conversions fail). Signed-off-by: Fabrice Gasnier --- drivers/iio/adc/stm32-dfsdm-core.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/iio/adc/stm32-dfsdm-core.c b/drivers/iio/adc/stm32-dfsdm-core.c index e50efdc..1d0d823 100644 --- a/drivers/iio/adc/stm32-dfsdm-core.c +++ b/drivers/iio/adc/stm32-dfsdm-core.c @@ -227,6 +227,11 @@ static int stm32_dfsdm_parse_of(struct platform_device *pdev, } priv->spi_clk_out_div = div_u64_rem(clk_freq, spi_freq, &rem) - 1; + if (!priv->spi_clk_out_div) { + /* spi_clk_out_div == 0 means ckout is OFF */ + dev_err(&pdev->dev, "spi-max-frequency not achievable\n"); + return -EINVAL; + } priv->dfsdm.spi_master_freq = spi_freq; if (rem) {