From: Guenter Roeck <linux@roeck-us.net>
Date: Fri, 20 Jan 2012 04:58:13 +0000 (-0800)
Subject: hwmon: (lm70) Register hwmon device after creating attribute files, and remove it... 
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=e200c14f60765ee3be6517659ec8fea06e299e39;p=deliverable%2Flinux.git

hwmon: (lm70) Register hwmon device after creating attribute files, and remove it first

Register hwmon device as last operation in the probe function to ensure that all
attribute files exist when accessed from user applications. Otherwise, there
is a short time frame where the device is registered as hwmon device but
sysfs attributes do not yet exist. This could result in applications erroneously
not detecting attributes.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---

diff --git a/drivers/hwmon/lm70.c b/drivers/hwmon/lm70.c
index 9c12ef3b863b..61c2ffbb9dd0 100644
--- a/drivers/hwmon/lm70.c
+++ b/drivers/hwmon/lm70.c
@@ -156,13 +156,6 @@ static int __devinit lm70_probe(struct spi_device *spi)
 	mutex_init(&p_lm70->lock);
 	p_lm70->chip = chip;
 
-	/* sysfs hook */
-	p_lm70->hwmon_dev = hwmon_device_register(&spi->dev);
-	if (IS_ERR(p_lm70->hwmon_dev)) {
-		dev_dbg(&spi->dev, "hwmon_device_register failed.\n");
-		status = PTR_ERR(p_lm70->hwmon_dev);
-		goto out_dev_reg_failed;
-	}
 	spi_set_drvdata(spi, p_lm70);
 
 	if ((status = device_create_file(&spi->dev, &dev_attr_temp1_input))
@@ -171,12 +164,20 @@ static int __devinit lm70_probe(struct spi_device *spi)
 		goto out_dev_create_file_failed;
 	}
 
+	/* sysfs hook */
+	p_lm70->hwmon_dev = hwmon_device_register(&spi->dev);
+	if (IS_ERR(p_lm70->hwmon_dev)) {
+		dev_dbg(&spi->dev, "hwmon_device_register failed.\n");
+		status = PTR_ERR(p_lm70->hwmon_dev);
+		goto out_dev_reg_failed;
+	}
+
 	return 0;
 
+out_dev_reg_failed:
+	device_remove_file(&spi->dev, &dev_attr_name);
 out_dev_create_file_failed:
 	device_remove_file(&spi->dev, &dev_attr_temp1_input);
-	hwmon_device_unregister(p_lm70->hwmon_dev);
-out_dev_reg_failed:
 	spi_set_drvdata(spi, NULL);
 	kfree(p_lm70);
 	return status;
@@ -186,9 +187,9 @@ static int __devexit lm70_remove(struct spi_device *spi)
 {
 	struct lm70 *p_lm70 = spi_get_drvdata(spi);
 
+	hwmon_device_unregister(p_lm70->hwmon_dev);
 	device_remove_file(&spi->dev, &dev_attr_temp1_input);
 	device_remove_file(&spi->dev, &dev_attr_name);
-	hwmon_device_unregister(p_lm70->hwmon_dev);
 	spi_set_drvdata(spi, NULL);
 	kfree(p_lm70);