hwmon: (ads1015) Fix build warning

The following build warning is seen in some configurations.

drivers/hwmon/ads1015.c: In function 'show_in':
drivers/hwmon/ads1015.c:129: warning: 'in' may be used uninitialized in this function

Fix by separating the register read function from the code converting the result
into mV.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Dirk Eibach <eibach@gdsys.de>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>
This commit is contained in:
Guenter Roeck 2012-04-09 13:53:00 -04:00
parent 00250ec909
commit 1196573fe4

View file

@ -59,14 +59,11 @@ struct ads1015_data {
struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
};
static int ads1015_read_value(struct i2c_client *client, unsigned int channel,
int *value)
static int ads1015_read_adc(struct i2c_client *client, unsigned int channel)
{
u16 config;
s16 conversion;
struct ads1015_data *data = i2c_get_clientdata(client);
unsigned int pga = data->channel_data[channel].pga;
int fullscale;
unsigned int data_rate = data->channel_data[channel].data_rate;
unsigned int conversion_time_ms;
int res;
@ -78,7 +75,6 @@ static int ads1015_read_value(struct i2c_client *client, unsigned int channel,
if (res < 0)
goto err_unlock;
config = res;
fullscale = fullscale_table[pga];
conversion_time_ms = DIV_ROUND_UP(1000, data_rate_table[data_rate]);
/* setup and start single conversion */
@ -105,33 +101,36 @@ static int ads1015_read_value(struct i2c_client *client, unsigned int channel,
}
res = i2c_smbus_read_word_swapped(client, ADS1015_CONVERSION);
if (res < 0)
goto err_unlock;
conversion = res;
mutex_unlock(&data->update_lock);
*value = DIV_ROUND_CLOSEST(conversion * fullscale, 0x7ff0);
return 0;
err_unlock:
mutex_unlock(&data->update_lock);
return res;
}
static int ads1015_reg_to_mv(struct i2c_client *client, unsigned int channel,
s16 reg)
{
struct ads1015_data *data = i2c_get_clientdata(client);
unsigned int pga = data->channel_data[channel].pga;
int fullscale = fullscale_table[pga];
return DIV_ROUND_CLOSEST(reg * fullscale, 0x7ff0);
}
/* sysfs callback function */
static ssize_t show_in(struct device *dev, struct device_attribute *da,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct i2c_client *client = to_i2c_client(dev);
int in;
int res;
int index = attr->index;
res = ads1015_read_value(client, attr->index, &in);
res = ads1015_read_adc(client, index);
if (res < 0)
return res;
return (res < 0) ? res : sprintf(buf, "%d\n", in);
return sprintf(buf, "%d\n", ads1015_reg_to_mv(client, index, res));
}
static const struct sensor_device_attribute ads1015_in[] = {