[PATCH] drivers/power/88pm860x_battery.c: use devm_request_threaded_irq

From: Julia Lawall
Date: Sat Dec 08 2012 - 11:16:30 EST


From: Julia Lawall <Julia.Lawall@xxxxxxx>

devm_request_threaded_irq requests and irq that is freed when a driver
detaches. This patch uses devm_request_threaded_irq for irqs that are
requested in the probe function of a platform device and are only freed in
the remove function.

Additionally, the original code used devm_kzalloc, but kfree. This would
lead to a double free. The problem was found using the following semantic
match (http://coccinelle.lip6.fr/):

// <smpl>
@@
expression x,e;
@@
x = devm_kzalloc(...)
... when != x = e
?-kfree(x,...);
// </smpl>

The error handling code in the probe function is also simplified in the
cases where there is now nothing to do other than return.

Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx>

---
drivers/power/88pm860x_battery.c | 24 ++++++++----------------
1 file changed, 8 insertions(+), 16 deletions(-)

diff --git a/drivers/power/88pm860x_battery.c b/drivers/power/88pm860x_battery.c
index 8bc80b0..b808177 100644
--- a/drivers/power/88pm860x_battery.c
+++ b/drivers/power/88pm860x_battery.c
@@ -915,15 +915,13 @@ static int pm860x_battery_probe(struct platform_device *pdev)
info->irq_cc = platform_get_irq(pdev, 0);
if (info->irq_cc <= 0) {
dev_err(&pdev->dev, "No IRQ resource!\n");
- ret = -EINVAL;
- goto out;
+ return -EINVAL;
}

info->irq_batt = platform_get_irq(pdev, 1);
if (info->irq_batt <= 0) {
dev_err(&pdev->dev, "No IRQ resource!\n");
- ret = -EINVAL;
- goto out;
+ return -EINVAL;
}

info->chip = chip;
@@ -957,10 +955,10 @@ static int pm860x_battery_probe(struct platform_device *pdev)

ret = power_supply_register(&pdev->dev, &info->battery);
if (ret)
- goto out;
+ return ret;
info->battery.dev->parent = &pdev->dev;

- ret = request_threaded_irq(info->irq_cc, NULL,
+ ret = devm_request_threaded_irq(&pdev->dev, info->irq_cc, NULL,
pm860x_coulomb_handler, IRQF_ONESHOT,
"coulomb", info);
if (ret < 0) {
@@ -969,23 +967,20 @@ static int pm860x_battery_probe(struct platform_device *pdev)
goto out_reg;
}

- ret = request_threaded_irq(info->irq_batt, NULL, pm860x_batt_handler,
- IRQF_ONESHOT, "battery", info);
+ ret = devm_request_threaded_irq(&pdev->dev, info->irq_batt, NULL,
+ pm860x_batt_handler,
+ IRQF_ONESHOT, "battery", info);
if (ret < 0) {
dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
info->irq_batt, ret);
- goto out_coulomb;
+ goto out_reg;
}


return 0;

-out_coulomb:
- free_irq(info->irq_cc, info);
out_reg:
power_supply_unregister(&info->battery);
-out:
- kfree(info);
return ret;
}

@@ -994,9 +989,6 @@ static int pm860x_battery_remove(struct platform_device *pdev)
struct pm860x_battery_info *info = platform_get_drvdata(pdev);

power_supply_unregister(&info->battery);
- free_irq(info->irq_batt, info);
- free_irq(info->irq_cc, info);
- kfree(info);
platform_set_drvdata(pdev, NULL);
return 0;
}

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/