From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     appana.durga.rao@xilinx.com, naga.sureshkumar.relli@xilinx.com,
        wg@grandegger.com, mkl@pengutronix.de, davem@davemloft.net,
        kuba@kernel.org, michal.simek@xilinx.com
Cc:     linux-can@vger.kernel.org, netdev@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH] can: xilinx_can: Check for error irq
Date:   Fri, 24 Dec 2021 10:13:24 +0800
Message-Id: <20211224021324.1447494-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

For the possible failure of the platform_get_irq(), the returned irq
could be error number and will finally cause the failure of the
request_irq().
Consider that platform_get_irq() can now in certain cases return
-EPROBE_DEFER, and the consequences of letting request_irq() effectively
convert that into -EINVAL, even at probe time rather than later on.
So it might be better to check just now.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/net/can/xilinx_can.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c
index 3b883e607d8b..a579b9b791ed 100644
--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -1762,7 +1762,12 @@ static int xcan_probe(struct platform_device *pdev)
 	spin_lock_init(&priv->tx_lock);
 
 	/* Get IRQ for the device */
-	ndev->irq = platform_get_irq(pdev, 0);
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0)
+		goto err_free;
+
+	ndev->irq = ret;
+
 	ndev->flags |= IFF_ECHO;	/* We support local echo */
 
 	platform_set_drvdata(pdev, ndev);
-- 
2.25.1