From 232449850229deeda84194e8a3c93a49ab6a043e Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Fri, 5 Mar 2010 22:17:23 +0100 Subject: [PATCH] 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 Signed-off-by: Jean Delvare --- drivers/hwmon/adt7411.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/hwmon/adt7411.c b/drivers/hwmon/adt7411.c index 9e9246fe2245..3471884e42d2 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); -- GitLab