The averaging rate of ina226 is hardcoded to 16 in the driver. Make it modifiable at run-time via a new sysfs attribute. While we're at it - add an additional variable to ina2xx_data, which holds the current configuration settings - this way we'll be able to restore the configuration in case of an unexpected chip reset. Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> --- Documentation/hwmon/ina2xx | 3 ++ drivers/hwmon/ina2xx.c | 132 +++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 131 insertions(+), 4 deletions(-) diff --git a/Documentation/hwmon/ina2xx b/Documentation/hwmon/ina2xx index 320dd69..a11256d 100644 --- a/Documentation/hwmon/ina2xx +++ b/Documentation/hwmon/ina2xx @@ -48,3 +48,6 @@ The shunt value in micro-ohms can be set via platform data or device tree at compile-time or via the shunt_resistor attribute in sysfs at run-time. Please refer to the Documentation/devicetree/bindings/i2c/ina2xx.txt for bindings if the device tree is used. + +The averaging rate of INA226 and INA230 can be changed via the avg_rate sysfs +attribute. The available rates are: 1, 4, 16, 64, 128, 256, 512 and 1024. diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c index 49537ea..d6fccad 100644 --- a/drivers/hwmon/ina2xx.c +++ b/drivers/hwmon/ina2xx.c @@ -68,6 +68,15 @@ #define INA2XX_RSHUNT_DEFAULT 10000 +/* bit masks for the averaging setting in the configuration register */ +#define INA226_AVG_RD_MASK 0x0E00 +#define INA226_AVG_WR_MASK 0xF1FF + +#define INA226_READ_AVG(reg) ((reg & INA226_AVG_RD_MASK) >> 9) + +/* common attrs, ina226 attrs and NULL */ +#define INA2XX_MAX_ATTRIBUTE_GROUPS 3 + enum ina2xx_ids { ina219, ina226 }; struct ina2xx_config { @@ -85,12 +94,14 @@ struct ina2xx_data { const struct ina2xx_config *config; long rshunt; + u16 curr_config; struct mutex update_lock; bool valid; unsigned long last_updated; int kind; + const struct attribute_group *groups[INA2XX_MAX_ATTRIBUTE_GROUPS]; u16 regs[INA2XX_MAX_REGISTERS]; }; @@ -115,6 +126,38 @@ static const struct ina2xx_config ina2xx_config[] = { }, }; +/* + * Available averaging rates for ina226. The indices correspond with + * the bit values expected by the chip (according to the ina226 datasheet, + * table 3 AVG bit settings, found at + * http://www.ti.com/lit/ds/symlink/ina226.pdf. + */ +static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 }; + +static int ina226_avg_bits(int avg) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ina226_avg_tab); i++) { + if (avg == ina226_avg_tab[i]) + return i; + } + + return -EINVAL; +} + +static int ina226_avg_val(int bits) +{ + /* + * Value read from the config register should be correct, but do check + * the boundary just in case. + */ + if (bits >= ARRAY_SIZE(ina226_avg_tab)) + return -ENODEV; + + return ina226_avg_tab[bits]; +} + static int ina2xx_calibrate(struct ina2xx_data *data) { return i2c_smbus_write_word_swapped(data->client, INA2XX_CALIBRATION, @@ -131,7 +174,7 @@ static int ina2xx_init(struct ina2xx_data *data) /* device configuration */ ret = i2c_smbus_write_word_swapped(client, INA2XX_CONFIG, - data->config->config_default); + data->curr_config); if (ret < 0) return ret; @@ -292,6 +335,66 @@ static ssize_t ina2xx_set_shunt(struct device *dev, return count; } +static ssize_t ina226_show_avg(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct ina2xx_data *data = ina2xx_update_device(dev); + int avg, i, written = 0; + const char *fmt; + + if (IS_ERR(data)) + return PTR_ERR(data); + + avg = ina226_avg_val(INA226_READ_AVG(data->regs[INA2XX_CONFIG])); + if (avg < 0) + return avg; + + for (i = 0; i < ARRAY_SIZE(ina226_avg_tab); i++) { + if (avg == ina226_avg_tab[i]) + fmt = "\t[%d]"; + else + fmt = "\t%d"; + + written += snprintf(buf + written, PAGE_SIZE - written, + fmt, ina226_avg_tab[i]); + } + written += snprintf(buf + written, PAGE_SIZE - written, "\n"); + + return written; +} + +static ssize_t ina226_set_avg(struct device *dev, + struct device_attribute *da, + const char *buf, size_t count) +{ + struct ina2xx_data *data = ina2xx_update_device(dev); + long val; + int status, avg; + + if (IS_ERR(data)) + return PTR_ERR(data); + + status = kstrtol(buf, 10, &val); + if (status < 0) + return status; + + avg = ina226_avg_bits(val); + if (avg < 0) + return avg; + + mutex_lock(&data->update_lock); + data->curr_config = (data->regs[INA2XX_CONFIG] & + INA226_AVG_WR_MASK) | (avg << 9); + status = i2c_smbus_write_word_swapped(data->client, + INA2XX_CONFIG, + data->curr_config); + mutex_unlock(&data->update_lock); + if (status < 0) + return status; + + return count; +} + /* shunt voltage */ static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ina2xx_show_value, NULL, INA2XX_SHUNT_VOLTAGE); @@ -313,6 +416,10 @@ static SENSOR_DEVICE_ATTR(shunt_resistor, S_IRUGO | S_IWUSR, ina2xx_show_value, ina2xx_set_shunt, INA2XX_CALIBRATION); +/* averaging rate */ +static SENSOR_DEVICE_ATTR(avg_rate, S_IRUGO | S_IWUSR, + ina226_show_avg, ina226_set_avg, 0); + /* pointers to created device attributes */ static struct attribute *ina2xx_attrs[] = { &sensor_dev_attr_in0_input.dev_attr.attr, @@ -322,7 +429,19 @@ static struct attribute *ina2xx_attrs[] = { &sensor_dev_attr_shunt_resistor.dev_attr.attr, NULL, }; -ATTRIBUTE_GROUPS(ina2xx); + +static const struct attribute_group ina2xx_group = { + .attrs = ina2xx_attrs, +}; + +static struct attribute *ina226_attrs[] = { + &sensor_dev_attr_avg_rate.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ina226_group = { + .attrs = ina226_attrs, +}; static int ina2xx_probe(struct i2c_client *client, const struct i2c_device_id *id) @@ -333,7 +452,7 @@ static int ina2xx_probe(struct i2c_client *client, struct ina2xx_data *data; struct device *hwmon_dev; u32 val; - int ret; + int ret, group = 0; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) return -ENODEV; @@ -355,6 +474,7 @@ static int ina2xx_probe(struct i2c_client *client, /* set the device type */ data->kind = id->driver_data; data->config = &ina2xx_config[data->kind]; + data->curr_config = data->config->config_default; data->client = client; if (data->rshunt <= 0 || @@ -369,8 +489,12 @@ static int ina2xx_probe(struct i2c_client *client, mutex_init(&data->update_lock); + data->groups[group++] = &ina2xx_group; + if (data->kind == ina226) + data->groups[group++] = &ina226_group; + hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, - data, ina2xx_groups); + data, data->groups); if (IS_ERR(hwmon_dev)) return PTR_ERR(hwmon_dev); -- 2.1.3 _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors