diff options
Diffstat (limited to 'drivers/hwmon/ds1621.c')
| -rw-r--r-- | drivers/hwmon/ds1621.c | 172 |
1 files changed, 83 insertions, 89 deletions
diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c index 7415381601c..53f88f51181 100644 --- a/drivers/hwmon/ds1621.c +++ b/drivers/hwmon/ds1621.c @@ -81,71 +81,84 @@ struct ds1621_data { u8 conf; /* Register encoding, combined */ }; -static int ds1621_probe(struct i2c_client *client, - const struct i2c_device_id *id); -static int ds1621_detect(struct i2c_client *client, int kind, - struct i2c_board_info *info); -static void ds1621_init_client(struct i2c_client *client); -static int ds1621_remove(struct i2c_client *client); -static struct ds1621_data *ds1621_update_client(struct device *dev); - -static const struct i2c_device_id ds1621_id[] = { - { "ds1621", ds1621 }, - { "ds1625", ds1621 }, - { } -}; -MODULE_DEVICE_TABLE(i2c, ds1621_id); - -/* This is the driver that will be inserted */ -static struct i2c_driver ds1621_driver = { - .class = I2C_CLASS_HWMON, - .driver = { - .name = "ds1621", - }, - .probe = ds1621_probe, - .remove = ds1621_remove, - .id_table = ds1621_id, - .detect = ds1621_detect, - .address_data = &addr_data, -}; - -/* All registers are word-sized, except for the configuration register. +/* Temperature registers are word-sized. DS1621 uses a high-byte first convention, which is exactly opposite to the SMBus standard. */ -static int ds1621_read_value(struct i2c_client *client, u8 reg) +static int ds1621_read_temp(struct i2c_client *client, u8 reg) { - if (reg == DS1621_REG_CONF) - return i2c_smbus_read_byte_data(client, reg); - else - return swab16(i2c_smbus_read_word_data(client, reg)); + int ret; + + ret = i2c_smbus_read_word_data(client, reg); + if (ret < 0) + return ret; + return swab16(ret); } -static int ds1621_write_value(struct i2c_client *client, u8 reg, u16 value) +static int ds1621_write_temp(struct i2c_client *client, u8 reg, u16 value) { - if (reg == DS1621_REG_CONF) - return i2c_smbus_write_byte_data(client, reg, value); - else - return i2c_smbus_write_word_data(client, reg, swab16(value)); + return i2c_smbus_write_word_data(client, reg, swab16(value)); } static void ds1621_init_client(struct i2c_client *client) { - int reg = ds1621_read_value(client, DS1621_REG_CONF); + u8 conf, new_conf; + + new_conf = conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); /* switch to continuous conversion mode */ - reg &= ~ DS1621_REG_CONFIG_1SHOT; + new_conf &= ~DS1621_REG_CONFIG_1SHOT; /* setup output polarity */ if (polarity == 0) - reg &= ~DS1621_REG_CONFIG_POLARITY; + new_conf &= ~DS1621_REG_CONFIG_POLARITY; else if (polarity == 1) - reg |= DS1621_REG_CONFIG_POLARITY; + new_conf |= DS1621_REG_CONFIG_POLARITY; - ds1621_write_value(client, DS1621_REG_CONF, reg); + if (conf != new_conf) + i2c_smbus_write_byte_data(client, DS1621_REG_CONF, new_conf); /* start conversion */ i2c_smbus_write_byte(client, DS1621_COM_START); } +static struct ds1621_data *ds1621_update_client(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct ds1621_data *data = i2c_get_clientdata(client); + u8 new_conf; + + mutex_lock(&data->update_lock); + + if (time_after(jiffies, data->last_updated + HZ + HZ / 2) + || !data->valid) { + int i; + + dev_dbg(&client->dev, "Starting ds1621 update\n"); + + data->conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); + + for (i = 0; i < ARRAY_SIZE(data->temp); i++) + data->temp[i] = ds1621_read_temp(client, + DS1621_REG_TEMP[i]); + + /* reset alarms if necessary */ + new_conf = data->conf; + if (data->temp[0] > data->temp[1]) /* input > min */ + new_conf &= ~DS1621_ALARM_TEMP_LOW; + if (data->temp[0] < data->temp[2]) /* input < max */ + new_conf &= ~DS1621_ALARM_TEMP_HIGH; + if (data->conf != new_conf) + i2c_smbus_write_byte_data(client, DS1621_REG_CONF, + new_conf); + + data->last_updated = jiffies; + data->valid = 1; + } + + mutex_unlock(&data->update_lock); + + return data; +} + static ssize_t show_temp(struct device *dev, struct device_attribute *da, char *buf) { @@ -160,13 +173,13 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *da, { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); struct i2c_client *client = to_i2c_client(dev); - struct ds1621_data *data = ds1621_update_client(dev); + struct ds1621_data *data = i2c_get_clientdata(client); u16 val = LM75_TEMP_TO_REG(simple_strtol(buf, NULL, 10)); mutex_lock(&data->update_lock); data->temp[attr->index] = val; - ds1621_write_value(client, DS1621_REG_TEMP[attr->index], - data->temp[attr->index]); + ds1621_write_temp(client, DS1621_REG_TEMP[attr->index], + data->temp[attr->index]); mutex_unlock(&data->update_lock); return count; } @@ -228,13 +241,14 @@ static int ds1621_detect(struct i2c_client *client, int kind, /* The NVB bit should be low if no EEPROM write has been requested during the latest 10ms, which is highly improbable in our case. */ - conf = ds1621_read_value(client, DS1621_REG_CONF); - if (conf & DS1621_REG_CONFIG_NVB) + conf = i2c_smbus_read_byte_data(client, DS1621_REG_CONF); + if (conf < 0 || conf & DS1621_REG_CONFIG_NVB) return -ENODEV; /* The 7 lowest bits of a temperature should always be 0. */ for (i = 0; i < ARRAY_SIZE(DS1621_REG_TEMP); i++) { - temp = ds1621_read_value(client, DS1621_REG_TEMP[i]); - if (temp & 0x007f) + temp = i2c_smbus_read_word_data(client, + DS1621_REG_TEMP[i]); + if (temp < 0 || (temp & 0x7f00)) return -ENODEV; } } @@ -294,45 +308,25 @@ static int ds1621_remove(struct i2c_client *client) return 0; } +static const struct i2c_device_id ds1621_id[] = { + { "ds1621", ds1621 }, + { "ds1625", ds1621 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ds1621_id); -static struct ds1621_data *ds1621_update_client(struct device *dev) -{ - struct i2c_client *client = to_i2c_client(dev); - struct ds1621_data *data = i2c_get_clientdata(client); - u8 new_conf; - - mutex_lock(&data->update_lock); - - if (time_after(jiffies, data->last_updated + HZ + HZ / 2) - || !data->valid) { - int i; - - dev_dbg(&client->dev, "Starting ds1621 update\n"); - - data->conf = ds1621_read_value(client, DS1621_REG_CONF); - - for (i = 0; i < ARRAY_SIZE(data->temp); i++) - data->temp[i] = ds1621_read_value(client, - DS1621_REG_TEMP[i]); - - /* reset alarms if necessary */ - new_conf = data->conf; - if (data->temp[0] > data->temp[1]) /* input > min */ - new_conf &= ~DS1621_ALARM_TEMP_LOW; - if (data->temp[0] < data->temp[2]) /* input < max */ - new_conf &= ~DS1621_ALARM_TEMP_HIGH; - if (data->conf != new_conf) - ds1621_write_value(client, DS1621_REG_CONF, - new_conf); - - data->last_updated = jiffies; - data->valid = 1; - } - - mutex_unlock(&data->update_lock); - - return data; -} +/* This is the driver that will be inserted */ +static struct i2c_driver ds1621_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "ds1621", + }, + .probe = ds1621_probe, + .remove = ds1621_remove, + .id_table = ds1621_id, + .detect = ds1621_detect, + .address_data = &addr_data, +}; static int __init ds1621_init(void) { |