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authorWolfram Sang <w.sang@pengutronix.de>2010-03-05 22:17:23 +0100
committerJean Delvare <khali@linux-fr.org>2010-03-05 22:17:23 +0100
commit232449850229deeda84194e8a3c93a49ab6a043e (patch)
treef9c6f1f51b2cd1ed84b873e87e500778f5e385e7 /drivers/hwmon
parentd84ca5b345c2b77ebf053d534ada6af2332a43b6 (diff)
downloadop-kernel-dev-232449850229deeda84194e8a3c93a49ab6a043e.zip
op-kernel-dev-232449850229deeda84194e8a3c93a49ab6a043e.tar.gz
hwmon: (adt7411) Improve locking
Add proper locking for the cached variables. Also get rid of ref_is_vdd, which became obsolete. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'drivers/hwmon')
-rw-r--r--drivers/hwmon/adt7411.c21
1 files changed, 14 insertions, 7 deletions
diff --git a/drivers/hwmon/adt7411.c b/drivers/hwmon/adt7411.c
index 9e9246f..3471884 100644
--- a/drivers/hwmon/adt7411.c
+++ b/drivers/hwmon/adt7411.c
@@ -48,9 +48,9 @@ static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };
struct adt7411_data {
struct mutex device_lock; /* for "atomic" device accesses */
+ struct mutex update_lock;
unsigned long next_update;
int vref_cached;
- bool ref_is_vdd;
struct device *hwmon_dev;
};
@@ -142,18 +142,18 @@ static ssize_t adt7411_show_input(struct device *dev,
int val;
u8 lsb_reg, lsb_shift;
+ mutex_lock(&data->update_lock);
if (time_after_eq(jiffies, data->next_update)) {
val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
if (val < 0)
- return val;
- data->ref_is_vdd = val & ADT7411_CFG3_REF_VDD;
+ goto exit_unlock;
- if (data->ref_is_vdd) {
+ if (val & ADT7411_CFG3_REF_VDD) {
val = adt7411_read_10_bit(client,
ADT7411_REG_INT_TEMP_VDD_LSB,
ADT7411_REG_VDD_MSB, 2);
if (val < 0)
- return val;
+ goto exit_unlock;
data->vref_cached = val * 7000 / 1024;
} else {
@@ -167,9 +167,13 @@ static ssize_t adt7411_show_input(struct device *dev,
lsb_shift = 2 * (nr & 0x03);
val = adt7411_read_10_bit(client, lsb_reg,
ADT7411_REG_EXT_TEMP_AIN1_MSB + nr, lsb_shift);
+ if (val < 0)
+ goto exit_unlock;
- return val < 0 ? val :
- sprintf(buf, "%u\n", val * data->vref_cached / 1024);
+ val = sprintf(buf, "%u\n", val * data->vref_cached / 1024);
+ exit_unlock:
+ mutex_unlock(&data->update_lock);
+ return val;
}
static ssize_t adt7411_show_bit(struct device *dev,
@@ -199,7 +203,9 @@ static ssize_t adt7411_set_bit(struct device *dev,
ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);
/* force update */
+ mutex_lock(&data->update_lock);
data->next_update = jiffies;
+ mutex_unlock(&data->update_lock);
return ret < 0 ? ret : count;
}
@@ -282,6 +288,7 @@ static int __devinit adt7411_probe(struct i2c_client *client,
i2c_set_clientdata(client, data);
mutex_init(&data->device_lock);
+ mutex_init(&data->update_lock);
ret = adt7411_modify_bit(client, ADT7411_REG_CFG1,
ADT7411_CFG1_START_MONITOR, 1);
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