[PATCH 3/5] use mutex instead of semaphore in SMSC LPC47M192 driver

Matthias Kaehlcke
2007-07-01T16:31:24Z

The SMSC LPC47M192 driver uses a semaphore as mutex. Use the mutex API
instead of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>

--

diff --git a/drivers/hwmon/smsc47m192.c b/drivers/hwmon/smsc47m192.c
index a012f39..7c5cfa2 100644
--- a/drivers/hwmon/smsc47m192.c
+++ b/drivers/hwmon/smsc47m192.c
@@ -31,6 +31,7 @@
#include <linux/hwmon-vid.h>
#include <linux/err.h>
#include <linux/sysfs.h>
+#include <linux/mutex.h>

/* Addresses to scan */
static unsigned short normal_i2c[] = { 0x2c, 0x2d, I2C_CLIENT_END };
@@ -97,7 +98,7 @@ static inline int TEMP_FROM_REG(s8 val)
struct smsc47m192_data {
struct i2c_client client;
struct class_device *class_dev;
- struct semaphore update_lock;
+ struct mutex update_lock;
char valid; /* !=0 if following fields are valid */
unsigned long last_updated; /* In jiffies */

@@ -164,11 +165,11 @@ static ssize_t set_in_min(struct device *dev, struct device_attribute *attr,
struct smsc47m192_data *data = i2c_get_clientdata(client);
unsigned long val = simple_strtoul(buf, NULL, 10);

- down(&data->update_lock);
+ mutex_lock(&data->update_lock);
data->in_min[nr] = IN_TO_REG(val, nr);
i2c_smbus_write_byte_data(client, SMSC47M192_REG_IN_MIN(nr),
data->in_min[nr]);
- up(&data->update_lock);
+ mutex_unlock(&data->update_lock);
return count;
}

@@ -181,11 +182,11 @@ static ssize_t set_in_max(struct device *dev, struct device_attribute *attr,
struct smsc47m192_data *data = i2c_get_clientdata(client);
unsigned long val = simple_strtoul(buf, NULL, 10);

- down(&data->update_lock);
+ mutex_lock(&data->update_lock);
data->in_max[nr] = IN_TO_REG(val, nr);
i2c_smbus_write_byte_data(client, SMSC47M192_REG_IN_MAX(nr),
data->in_max[nr]);
- up(&data->update_lock);
+ mutex_unlock(&data->update_lock);
return count;
}

@@ -243,11 +244,11 @@ static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
struct smsc47m192_data *data = i2c_get_clientdata(client);
long val = simple_strtol(buf, NULL, 10);

- down(&data->update_lock);
+ mutex_lock(&data->update_lock);
data->temp_min[nr] = TEMP_TO_REG(val);
i2c_smbus_write_byte_data(client, SMSC47M192_REG_TEMP_MIN[nr],
data->temp_min[nr]);
- up(&data->update_lock);
+ mutex_unlock(&data->update_lock);
return count;
}

@@ -260,11 +261,11 @@ static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
struct smsc47m192_data *data = i2c_get_clientdata(client);
long val = simple_strtol(buf, NULL, 10);

- down(&data->update_lock);
+ mutex_lock(&data->update_lock);
data->temp_max[nr] = TEMP_TO_REG(val);
i2c_smbus_write_byte_data(client, SMSC47M192_REG_TEMP_MAX[nr],
data->temp_max[nr]);
- up(&data->update_lock);
+ mutex_unlock(&data->update_lock);
return count;
}

@@ -287,7 +288,7 @@ static ssize_t set_temp_offset(struct device *dev, struct device_attribute
u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);
long val = simple_strtol(buf, NULL, 10);

- down(&data->update_lock);
+ mutex_lock(&data->update_lock);
data->temp_offset[nr] = TEMP_TO_REG(val);
if (nr>1)
i2c_smbus_write_byte_data(client,
@@ -303,7 +304,7 @@ static ssize_t set_temp_offset(struct device *dev, struct device_attribute
} else if ((sfr & 0x10) == (nr==0 ? 0x10 : 0))
i2c_smbus_write_byte_data(client,
SMSC47M192_REG_TEMP_OFFSET(nr), 0);
- up(&data->update_lock);
+ mutex_unlock(&data->update_lock);
return count;
}

@@ -531,7 +532,7 @@ static int smsc47m192_detect(struct i2c_adapter *adapter, int address,
/* Fill in the remaining client fields and put into the global list */
strlcpy(client->name, "smsc47m192", I2C_NAME_SIZE);
data->vrm = vid_which_vrm();
- init_MUTEX(&data->update_lock);
+ mutex_init(&data->update_lock);

/* Tell the I2C layer a new client has arrived */
if ((err = i2c_attach_client(client)))
@@ -594,7 +595,7 @@ static struct smsc47m192_data *smsc47m192_update_device(struct device *dev)
struct smsc47m192_data *data = i2c_get_clientdata(client);
int i, config;

- down(&data->update_lock);
+ mutex_lock(&data->update_lock);

if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
|| !data->valid) {
@@ -645,7 +646,7 @@ static struct smsc47m192_data *smsc47m192_update_device(struct device *dev)
data->valid = 1;
}

- up(&data->update_lock);
+ mutex_unlock(&data->update_lock);

return data;
}

--
Matthias Kaehlcke
Linux Application Developer
Barcelona

El camino se hace al andar
(Antonio Machado)