From patchwork Thu Jul 6 10:04:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shuijing Li X-Patchwork-Id: 13303442 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 8B8D0EB64D9 for ; Thu, 6 Jul 2023 10:05:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version: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:In-Reply-To:References:List-Owner; bh=TS+0nfycyMyZboLtN8mtKKdv0Ar+eMXmyw7XCZMA2LM=; b=HlbH2C2kAyZJK+YWGpkOMPAGAz jjs+7GeyjKOhlhd9Gv4zCPSw6KTHDPr6tyXnBkUJCVcGM5nRkPeVETer+uAyPiGeKoYA+a/unuPog +2iVuL10Wt9Svnp2NfU2ZQ2dvRanP7flj53hDGWBb60TYWYCril3cIC/oQHuAM+sh0LUQieiwufgD y/S1I7fjartv/vAmJVRGCpV2ub2WZJaxDCWvN5x7g65EVT4GqPJZLECzuLM/Mds0PnnGrKA+SlSI5 giirI/nAJc0o1M7/O2Rz+YymdQRrM4g5EJMxiI0brkqAy8qIt0xikNCXAH+DZnlYYTQb0RcUtyDNz kLGS8Neg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qHLqy-0019sB-1I; Thu, 06 Jul 2023 10:04:48 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qHLqw-0019rD-1i; Thu, 06 Jul 2023 10:04:47 +0000 X-UUID: 85062c6c1be411ee912e1518a6540028-20230706 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=TS+0nfycyMyZboLtN8mtKKdv0Ar+eMXmyw7XCZMA2LM=; b=fJiHurZXnnY+Lx6TfYtKU5N9yAVtg4kPU60MYMbHE+FqvFav2JzXuC7wRap1ytOAmVhpZigstnjRiFDC3Cer7+mgJ559SiDzZ0nVlIrMax4is+kLdeUeW2zgmjBxVRHIQM/mGQOTUeyGIAcD+XbpzQARdMJ44N1/w67IVy8cVJ0=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.27,REQID:83ff46d5-f2ff-46fe-a6da-4e58079c5b6c,IP:0,U RL:0,TC:0,Content:-25,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:-25 X-CID-META: VersionHash:01c9525,CLOUDID:33eec482-5a99-42ae-a2dd-e4afb731b474,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:-3,IP:nil,U RL:11|1,File:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR: NO X-CID-BVR: 0 X-CID-BAS: 0,_,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_ULN X-UUID: 85062c6c1be411ee912e1518a6540028-20230706 Received: from mtkmbs13n2.mediatek.inc [(172.21.101.108)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1489335439; Thu, 06 Jul 2023 03:04:39 -0700 Received: from mtkmbs13n1.mediatek.inc (172.21.101.193) by MTKMBS14N1.mediatek.inc (172.21.101.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Thu, 6 Jul 2023 18:04:36 +0800 Received: from mszsdhlt06.gcn.mediatek.inc (10.16.6.206) by mtkmbs13n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Thu, 6 Jul 2023 18:04:36 +0800 From: Shuijing Li To: , , , CC: , , , , , , , Shuijing Li Subject: [PATCH] pwm: mtk_disp: fix disp_pwm coverity issue Date: Thu, 6 Jul 2023 18:04:54 +0800 Message-ID: <20230706100454.28998-1-shuijing.li@mediatek.com> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230706_030446_595555_DB929CD0 X-CRM114-Status: UNSURE ( 9.52 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-mediatek@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-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org 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);