diff --git a/drivers/hwmon/ultra45_env.c b/drivers/hwmon/ultra45_env.c
index b9a87e8..c315c59 100644
--- a/drivers/hwmon/ultra45_env.c
+++ b/drivers/hwmon/ultra45_env.c
@@ -1,4 +1,5 @@
-/* ultra45_env.c: Driver for Ultra45 PIC16F747 environmental monitor.
+/*
+ * ultra45_env.c: Driver for Ultra45 PIC16F747 environmental monitor.
  *
  * Copyright (C) 2008 David S. Miller <davem@davemloft.net>
  */
@@ -82,7 +83,8 @@
 	spin_unlock(&p->lock);
 }
 
-/* There seems to be a adr7462 providing these values, thus a lot
+/*
+ * There seems to be a adr7462 providing these values, thus a lot
  * of these calculations are borrowed from the adt7470 driver.
  */
 #define FAN_PERIOD_TO_RPM(x)	((90000 * 60) / (x))
@@ -90,7 +92,8 @@
 #define FAN_PERIOD_INVALID	(0xff << 8)
 #define FAN_DATA_VALID(x)	((x) && (x) != FAN_PERIOD_INVALID)
 
-static ssize_t show_fan_speed(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t show_fan_speed(struct device *dev, struct device_attribute *attr,
+			      char *buf)
 {
 	int fan_nr = to_sensor_dev_attr(attr)->index;
 	struct env *p = dev_get_drvdata(dev);
@@ -111,10 +114,15 @@
 			     const char *buf, size_t count)
 {
 	int fan_nr = to_sensor_dev_attr(attr)->index;
-	int rpm = simple_strtol(buf, NULL, 10);
+	unsigned long rpm;
 	struct env *p = dev_get_drvdata(dev);
 	int period;
 	u8 val;
+	int err;
+
+	err = kstrtoul(buf, 10, &rpm);
+	if (err)
+		return err;
 
 	if (!rpm)
 		return -EINVAL;
@@ -126,7 +134,8 @@
 	return count;
 }
 
-static ssize_t show_fan_fault(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t show_fan_fault(struct device *dev, struct device_attribute *attr,
+			      char *buf)
 {
 	int fan_nr = to_sensor_dev_attr(attr)->index;
 	struct env *p = dev_get_drvdata(dev);
@@ -148,7 +157,8 @@
 
 static SENSOR_DEVICE_ATTR(psu_fan_fault, S_IRUGO, show_fan_fault, NULL, 6);
 
-static ssize_t show_temp(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
+			 char *buf)
 {
 	int temp_nr = to_sensor_dev_attr(attr)->index;
 	struct env *p = dev_get_drvdata(dev);
@@ -168,7 +178,8 @@
 static SENSOR_DEVICE_ATTR(front_panel_temp, S_IRUGO, show_temp, NULL, 7);
 static SENSOR_DEVICE_ATTR(psu_temp, S_IRUGO, show_temp, NULL, 13);
 
-static ssize_t show_stat_bit(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t show_stat_bit(struct device *dev, struct device_attribute *attr,
+			     char *buf)
 {
 	int index = to_sensor_dev_attr(attr)->index;
 	struct env *p = dev_get_drvdata(dev);
@@ -181,9 +192,11 @@
 static SENSOR_DEVICE_ATTR(fan_failure, S_IRUGO, show_stat_bit, NULL, 0);
 static SENSOR_DEVICE_ATTR(env_bus_busy, S_IRUGO, show_stat_bit, NULL, 1);
 static SENSOR_DEVICE_ATTR(env_data_stale, S_IRUGO, show_stat_bit, NULL, 2);
-static SENSOR_DEVICE_ATTR(tpm_self_test_passed, S_IRUGO, show_stat_bit, NULL, 3);
+static SENSOR_DEVICE_ATTR(tpm_self_test_passed, S_IRUGO, show_stat_bit, NULL,
+			  3);
 
-static ssize_t show_fwver(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t show_fwver(struct device *dev, struct device_attribute *attr,
+			  char *buf)
 {
 	struct env *p = dev_get_drvdata(dev);
 	u8 val;
@@ -194,7 +207,8 @@
 
 static SENSOR_DEVICE_ATTR(firmware_version, S_IRUGO, show_fwver, NULL, 0);
 
-static ssize_t show_name(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t show_name(struct device *dev, struct device_attribute *attr,
+			 char *buf)
 {
 	return sprintf(buf, "ultra45\n");
 }