[PATCH v2] ipmi:bt-bmc: Fix error handling and status check

From: Tang Bin <tangbin@cmss.chinamobile.com>
To: minyard@acm.org, arnd@arndb.de, gregkh@linuxfoundation.org
Cc: openipmi-developer@lists.sourceforge.net,
	linux-kernel@vger.kernel.org,
	Tang Bin <tangbin@cmss.chinamobile.com>,
	Shengju Zhang <zhangshengju@cmss.chinamobile.com>
Subject: [PATCH v2] ipmi:bt-bmc: Fix error handling and status check
Date: Sat, 18 Apr 2020 16:02:29 +0800	[thread overview]
Message-ID: <20200418080228.19028-1-tangbin@cmss.chinamobile.com> (raw)

If the function platform_get_irq() failed, the negative
value returned will not be detected here. So fix error
handling in bt_bmc_config_irq(). And if devm_request_irq()
failed, 'bt_bmc->irq' is assigned to zero maybe redundant,
it may be more suitable for using the correct negative values
to make the status check in the function bt_bmc_remove().

Signed-off-by: Shengju Zhang <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
---
Changes from v1
 - fix the code of status check
---
 drivers/char/ipmi/bt-bmc.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/char/ipmi/bt-bmc.c b/drivers/char/ipmi/bt-bmc.c
index cd0349bff..33d3a5d50 100644
--- a/drivers/char/ipmi/bt-bmc.c
+++ b/drivers/char/ipmi/bt-bmc.c
@@ -399,15 +399,14 @@ static int bt_bmc_config_irq(struct bt_bmc *bt_bmc,
 	struct device *dev = &pdev->dev;
 	int rc;
 
-	bt_bmc->irq = platform_get_irq(pdev, 0);
-	if (!bt_bmc->irq)
-		return -ENODEV;
+	bt_bmc->irq = platform_get_irq_optional(pdev, 0);
+	if (bt_bmc->irq < 0)
+		return bt_bmc->irq;
 
 	rc = devm_request_irq(dev, bt_bmc->irq, bt_bmc_irq, IRQF_SHARED,
 			      DEVICE_NAME, bt_bmc);
 	if (rc < 0) {
 		dev_warn(dev, "Unable to request IRQ %d\n", bt_bmc->irq);
-		bt_bmc->irq = 0;
 		return rc;
 	}
 
@@ -474,7 +473,7 @@ static int bt_bmc_probe(struct platform_device *pdev)
 
 	bt_bmc_config_irq(bt_bmc, pdev);
 
-	if (bt_bmc->irq) {
+	if (bt_bmc->irq >= 0) {
 		dev_info(dev, "Using IRQ %d\n", bt_bmc->irq);
 	} else {
 		dev_info(dev, "No IRQ; using timer\n");
@@ -500,7 +499,7 @@ static int bt_bmc_remove(struct platform_device *pdev)
 	struct bt_bmc *bt_bmc = dev_get_drvdata(&pdev->dev);
 
 	misc_deregister(&bt_bmc->miscdev);
-	if (!bt_bmc->irq)
+	if (bt_bmc->irq < 0)
 		del_timer_sync(&bt_bmc->poll_timer);
 	return 0;
 }
-- 
2.20.1.windows.1



