Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Fugang Duan <fugang.duan@nxp.com>,
        Joakim Zhang <qiangqing.zhang@nxp.com>,
        "David S . Miller" <davem@davemloft.net>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: [PATCH 4.14 58/88] net: fec_ptp: add clock rate zero check
Date:   Mon, 28 Jun 2021 10:35:58 -0400
Message-Id: <20210628143628.33342-59-sashal@kernel.org>
In-Reply-To: <20210628143628.33342-1-sashal@kernel.org>
References: <20210628143628.33342-1-sashal@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Fugang Duan <fugang.duan@nxp.com>

commit cb3cefe3f3f8af27c6076ef7d1f00350f502055d upstream.

Add clock rate zero check to fix coverity issue of "divide by 0".

Fixes: commit 85bd1798b24a ("net: fec: fix spin_lock dead lock")
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/freescale/fec_ptp.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c
index e63df6455fba..40c5c09f60dc 100644
--- a/drivers/net/ethernet/freescale/fec_ptp.c
+++ b/drivers/net/ethernet/freescale/fec_ptp.c
@@ -586,6 +586,10 @@ void fec_ptp_init(struct platform_device *pdev)
 	fep->ptp_caps.enable = fec_ptp_enable;
 
 	fep->cycle_speed = clk_get_rate(fep->clk_ptp);
+	if (!fep->cycle_speed) {
+		fep->cycle_speed = NSEC_PER_SEC;
+		dev_err(&fep->pdev->dev, "clk_ptp clock rate is zero\n");
+	}
 	fep->ptp_inc = NSEC_PER_SEC / fep->cycle_speed;
 
 	spin_lock_init(&fep->tmreg_lock);
-- 
2.30.2