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 E4394EB64DC for ; Thu, 6 Jul 2023 12:29:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231889AbjGFM3T (ORCPT ); Thu, 6 Jul 2023 08:29:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36676 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230445AbjGFM3Q (ORCPT ); Thu, 6 Jul 2023 08:29:16 -0400 Received: from mail-wm1-x32c.google.com (mail-wm1-x32c.google.com [IPv6:2a00:1450:4864:20::32c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C900E171A for ; Thu, 6 Jul 2023 05:29:14 -0700 (PDT) Received: by mail-wm1-x32c.google.com with SMTP id 5b1f17b1804b1-3fbc5d5742bso6840045e9.2 for ; Thu, 06 Jul 2023 05:29:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20221208.gappssmtp.com; s=20221208; t=1688646553; x=1691238553; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=QrwyGG22yUz0pXaaxwTuGI5EuvBFjwW6o/zgDSSwkOQ=; b=Lgf1cOi+4+QGjJ6vTEGvJWc7DzjQzfv4w5BKVmRE40HSst27WRxPaOwU150CLSXJ4j BO+HNRiJ1qXMampj7+/nE6mFbHRSRf0vi+7jG1/JddtB6urUwJiinZj33ugaWTSzNx3q A4c2ryH1s9an3latetN75IwkfRPlx+fk842mO63qnWoz5ADaoP1OmvMep52wcA+K3mcU HOZGbBB1RR9daw2jLO6jKBkgYgxjCY0S8W/Pgwgrnybzzyh1Dvqv6138oMRL+ikpYh9g /NWnaO7yQrhKl1UcQTelDCmA6+H7SEthcRmzLsGS4kvwV+ZJ2Foy2cLZYpr3ZSiUsKyT 5TUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1688646553; x=1691238553; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=QrwyGG22yUz0pXaaxwTuGI5EuvBFjwW6o/zgDSSwkOQ=; b=f1xh6yKYDcMiXLQuGwlo2UbbDY6EYzXGp7W9ktjcC4rIRA+tJkE2tdjVI9rg29Sptl hglWnfhLAvfCJmLt2o8ESk+TaveqUobviUENGRb95IR2OEJtzeMo5Ar+3evn5Z5SUm47 AV7bY0kcxmslBuUUcjD00rvDaOTO4c7FqadXCpJQ6L+r7BC/Ys4tuZB5CwyCV90nRvOZ b2FVugHT0wEjZVPMfGHcFXKwpvgC+zyP/MNzNnmpi8ikaugL1PXhpATmjcH1d98JnvmQ jGhWStwxaqrSRcDFJqEMbXu3ullHmXgmIolL/grDqUcvtQpCE4CnA+wnkvq6MkmJFjJt NM5w== X-Gm-Message-State: ABy/qLbB/NyYkMx9EYMwVhxYHQ+PnwBp41I7ED6+oa6FbnRm51+RN9vi QX2xlyi62IDTZuy0RmgHMJXsWg== X-Google-Smtp-Source: APBJJlENtsBPpzfe/86erIipmcvmcmpI0mPj2K7COvY/9J7rNN04Fa6U7vYjLisS/xtXgMELnlW8qQ== X-Received: by 2002:a7b:c5d4:0:b0:3fa:9e61:19ed with SMTP id n20-20020a7bc5d4000000b003fa9e6119edmr1221201wmk.23.1688646553292; Thu, 06 Jul 2023 05:29:13 -0700 (PDT) Received: from [192.168.1.172] ([93.5.22.158]) by smtp.gmail.com with ESMTPSA id f14-20020adff44e000000b003142ea7a661sm1799342wrp.21.2023.07.06.05.29.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 06 Jul 2023 05:29:12 -0700 (PDT) Message-ID: <55c3a448-e6c6-5e04-2cee-b2a18f0033e3@baylibre.com> Date: Thu, 6 Jul 2023 14:29:11 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH] pwm: mtk_disp: fix disp_pwm coverity issue Content-Language: en-US To: Shuijing Li , thierry.reding@gmail.com, u.kleine-koenig@pengutronix.de, matthias.bgg@gmail.com, angelogioacchino.delregno@collabora.com Cc: devicetree@vger.kernel.org, linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Project_Global_Chrome_Upstream_Group@mediatek.com, jitao.shi@mediatek.com References: <20230706100454.28998-1-shuijing.li@mediatek.com> From: Alexandre Mergnat In-Reply-To: <20230706100454.28998-1-shuijing.li@mediatek.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/07/2023 12:04, Shuijing Li wrote: > There is a coverity issue in the original mtk_disp_pwm_get_state() > function. In function call DIV64_U64_ROUND_UP, division by expression > Which may be zero has undefined behavior. > Fix this accordingly. > > Signed-off-by: Shuijing Li > --- > drivers/pwm/pwm-mtk-disp.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c > index 79e321e96f56..ca00058a6ef4 100644 > --- a/drivers/pwm/pwm-mtk-disp.c > +++ b/drivers/pwm/pwm-mtk-disp.c > @@ -196,6 +196,14 @@ static int mtk_disp_pwm_get_state(struct pwm_chip *chip, > return err; > } > > + rate = clk_get_rate(mdp->clk_main); > + if (rate <= 0) { > + dev_err(chip->dev, "Can't get rate: %pe\n", ERR_PTR(rate)); > + clk_disable_unprepare(mdp->clk_mm); > + clk_disable_unprepare(mdp->clk_main); > + return err; > + } > + > /* > * Apply DISP_PWM_DEBUG settings to choose whether to enable or disable > * registers double buffer and manual commit to working register before > @@ -206,7 +214,6 @@ static int mtk_disp_pwm_get_state(struct pwm_chip *chip, > mdp->data->bls_debug_mask, > mdp->data->bls_debug_mask); > > - rate = clk_get_rate(mdp->clk_main); > con0 = readl(mdp->base + mdp->data->con0); > con1 = readl(mdp->base + mdp->data->con1); > pwm_en = readl(mdp->base + DISP_PWM_EN); IMHO, it should be done int the function `mtk_disp_pwm_apply` too. Do you agree ? -- Regards, Alexandre