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-rw-r--r--drivers/iio/adc/ina2xx-adc.c52
1 files changed, 46 insertions, 6 deletions
diff --git a/drivers/iio/adc/ina2xx-adc.c b/drivers/iio/adc/ina2xx-adc.c
index ff31f5b49a41..dd4ff08d7b62 100644
--- a/drivers/iio/adc/ina2xx-adc.c
+++ b/drivers/iio/adc/ina2xx-adc.c
@@ -111,7 +111,7 @@ struct ina2xx_chip_info {
struct task_struct *task;
const struct ina2xx_config *config;
struct mutex state_lock;
- long rshunt;
+ unsigned int shunt_resistor;
int avg;
s64 prev_ns; /* track buffer capture time, check for underruns*/
int int_time_vbus; /* Bus voltage integration time uS */
@@ -349,6 +349,42 @@ static ssize_t ina2xx_allow_async_readout_store(struct device *dev,
return len;
}
+static int set_shunt_resistor(struct ina2xx_chip_info *chip, unsigned int val)
+{
+ if (val <= 0 || val > chip->config->calibration_factor)
+ return -EINVAL;
+
+ chip->shunt_resistor = val;
+ return 0;
+}
+
+static ssize_t ina2xx_shunt_resistor_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev));
+
+ return sprintf(buf, "%d\n", chip->shunt_resistor);
+}
+
+static ssize_t ina2xx_shunt_resistor_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev));
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul((const char *) buf, 10, &val);
+ if (ret)
+ return ret;
+
+ ret = set_shunt_resistor(chip, val);
+ if (ret)
+ return ret;
+
+ return len;
+}
#define INA2XX_CHAN(_type, _index, _address) { \
.type = (_type), \
@@ -545,9 +581,14 @@ static IIO_DEVICE_ATTR(in_allow_async_readout, S_IRUGO | S_IWUSR,
ina2xx_allow_async_readout_show,
ina2xx_allow_async_readout_store, 0);
+static IIO_DEVICE_ATTR(in_shunt_resistor, S_IRUGO | S_IWUSR,
+ ina2xx_shunt_resistor_show,
+ ina2xx_shunt_resistor_store, 0);
+
static struct attribute *ina2xx_attributes[] = {
&iio_dev_attr_in_allow_async_readout.dev_attr.attr,
&iio_const_attr_integration_time_available.dev_attr.attr,
+ &iio_dev_attr_in_shunt_resistor.dev_attr.attr,
NULL,
};
@@ -579,7 +620,7 @@ static int ina2xx_init(struct ina2xx_chip_info *chip, unsigned int config)
* to the user for now.
*/
regval = DIV_ROUND_CLOSEST(chip->config->calibration_factor,
- chip->rshunt);
+ chip->shunt_resistor);
return regmap_write(chip->regmap, INA2XX_CALIBRATION, regval);
}
@@ -612,10 +653,9 @@ static int ina2xx_probe(struct i2c_client *client,
val = INA2XX_RSHUNT_DEFAULT;
}
- if (val <= 0 || val > chip->config->calibration_factor)
- return -ENODEV;
-
- chip->rshunt = val;
+ ret = set_shunt_resistor(chip, val);
+ if (ret)
+ return ret;
mutex_init(&chip->state_lock);