hwmon: (ina2xx) Implement alert functions

Implement alert functions for INA226, INA230 and INA231. Expose 06h
Mask/Enable and 07h Alert Limit registers via alert setting and alarm
files.

Signed-off-by: Alex Qiu <xqiu@google.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Alex Qiu 2020-05-04 17:59:45 -07:00 committed by Guenter Roeck
parent b58bd4c6df
commit 5a56a39be7
2 changed files with 202 additions and 0 deletions

View File

@ -99,6 +99,25 @@ Sysfs entries for ina226, ina230 and ina231 only
------------------------------------------------
======================= ====================================================
in0_lcrit Critical low shunt voltage
in0_crit Critical high shunt voltage
in0_lcrit_alarm Shunt voltage critical low alarm
in0_crit_alarm Shunt voltage critical high alarm
in1_lcrit Critical low bus voltage
in1_crit Critical high bus voltage
in1_lcrit_alarm Bus voltage critical low alarm
in1_crit_alarm Bus voltage critical high alarm
power1_crit Critical high power
power1_crit_alarm Power critical high alarm
update_interval data conversion time; affects number of samples used
to average results for shunt and bus voltages.
======================= ====================================================
.. note::
- Configure `shunt_resistor` before configure `power1_crit`, because power
value is calculated based on `shunt_resistor` set.
- Because of the underlying register implementation, only one `*crit` setting
and its `alarm` can be active. Writing to one `*crit` setting clears other
`*crit` settings and alarms. Writing 0 to any `*crit` setting clears all
`*crit` settings and alarms.

View File

@ -74,6 +74,17 @@
#define INA226_READ_AVG(reg) (((reg) & INA226_AVG_RD_MASK) >> 9)
#define INA226_SHIFT_AVG(val) ((val) << 9)
/* bit number of alert functions in Mask/Enable Register */
#define INA226_SHUNT_OVER_VOLTAGE_BIT 15
#define INA226_SHUNT_UNDER_VOLTAGE_BIT 14
#define INA226_BUS_OVER_VOLTAGE_BIT 13
#define INA226_BUS_UNDER_VOLTAGE_BIT 12
#define INA226_POWER_OVER_LIMIT_BIT 11
/* bit mask for alert config bits of Mask/Enable Register */
#define INA226_ALERT_CONFIG_MASK 0xFC00
#define INA226_ALERT_FUNCTION_FLAG BIT(4)
/* common attrs, ina226 attrs and NULL */
#define INA2XX_MAX_ATTRIBUTE_GROUPS 3
@ -303,6 +314,145 @@ static ssize_t ina2xx_value_show(struct device *dev,
ina2xx_get_value(data, attr->index, regval));
}
static int ina226_reg_to_alert(struct ina2xx_data *data, u8 bit, u16 regval)
{
int reg;
switch (bit) {
case INA226_SHUNT_OVER_VOLTAGE_BIT:
case INA226_SHUNT_UNDER_VOLTAGE_BIT:
reg = INA2XX_SHUNT_VOLTAGE;
break;
case INA226_BUS_OVER_VOLTAGE_BIT:
case INA226_BUS_UNDER_VOLTAGE_BIT:
reg = INA2XX_BUS_VOLTAGE;
break;
case INA226_POWER_OVER_LIMIT_BIT:
reg = INA2XX_POWER;
break;
default:
/* programmer goofed */
WARN_ON_ONCE(1);
return 0;
}
return ina2xx_get_value(data, reg, regval);
}
/*
* Turns alert limit values into register values.
* Opposite of the formula in ina2xx_get_value().
*/
static s16 ina226_alert_to_reg(struct ina2xx_data *data, u8 bit, int val)
{
switch (bit) {
case INA226_SHUNT_OVER_VOLTAGE_BIT:
case INA226_SHUNT_UNDER_VOLTAGE_BIT:
val *= data->config->shunt_div;
return clamp_val(val, SHRT_MIN, SHRT_MAX);
case INA226_BUS_OVER_VOLTAGE_BIT:
case INA226_BUS_UNDER_VOLTAGE_BIT:
val = (val * 1000) << data->config->bus_voltage_shift;
val = DIV_ROUND_CLOSEST(val, data->config->bus_voltage_lsb);
return clamp_val(val, 0, SHRT_MAX);
case INA226_POWER_OVER_LIMIT_BIT:
val = DIV_ROUND_CLOSEST(val, data->power_lsb_uW);
return clamp_val(val, 0, USHRT_MAX);
default:
/* programmer goofed */
WARN_ON_ONCE(1);
return 0;
}
}
static ssize_t ina226_alert_show(struct device *dev,
struct device_attribute *da, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ina2xx_data *data = dev_get_drvdata(dev);
int regval;
int val = 0;
int ret;
mutex_lock(&data->config_lock);
ret = regmap_read(data->regmap, INA226_MASK_ENABLE, &regval);
if (ret)
goto abort;
if (regval & BIT(attr->index)) {
ret = regmap_read(data->regmap, INA226_ALERT_LIMIT, &regval);
if (ret)
goto abort;
val = ina226_reg_to_alert(data, attr->index, regval);
}
ret = snprintf(buf, PAGE_SIZE, "%d\n", val);
abort:
mutex_unlock(&data->config_lock);
return ret;
}
static ssize_t ina226_alert_store(struct device *dev,
struct device_attribute *da,
const char *buf, size_t count)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ina2xx_data *data = dev_get_drvdata(dev);
unsigned long val;
int ret;
ret = kstrtoul(buf, 10, &val);
if (ret < 0)
return ret;
/*
* Clear all alerts first to avoid accidentally triggering ALERT pin
* due to register write sequence. Then, only enable the alert
* if the value is non-zero.
*/
mutex_lock(&data->config_lock);
ret = regmap_update_bits(data->regmap, INA226_MASK_ENABLE,
INA226_ALERT_CONFIG_MASK, 0);
if (ret < 0)
goto abort;
ret = regmap_write(data->regmap, INA226_ALERT_LIMIT,
ina226_alert_to_reg(data, attr->index, val));
if (ret < 0)
goto abort;
if (val != 0) {
ret = regmap_update_bits(data->regmap, INA226_MASK_ENABLE,
INA226_ALERT_CONFIG_MASK,
BIT(attr->index));
if (ret < 0)
goto abort;
}
ret = count;
abort:
mutex_unlock(&data->config_lock);
return ret;
}
static ssize_t ina226_alarm_show(struct device *dev,
struct device_attribute *da, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ina2xx_data *data = dev_get_drvdata(dev);
int regval;
int alarm = 0;
int ret;
ret = regmap_read(data->regmap, INA226_MASK_ENABLE, &regval);
if (ret)
return ret;
alarm = (regval & BIT(attr->index)) &&
(regval & INA226_ALERT_FUNCTION_FLAG);
return snprintf(buf, PAGE_SIZE, "%d\n", alarm);
}
/*
* In order to keep calibration register value fixed, the product
* of current_lsb and shunt_resistor should also be fixed and equal
@ -392,15 +542,38 @@ static ssize_t ina226_interval_show(struct device *dev,
/* shunt voltage */
static SENSOR_DEVICE_ATTR_RO(in0_input, ina2xx_value, INA2XX_SHUNT_VOLTAGE);
/* shunt voltage over/under voltage alert setting and alarm */
static SENSOR_DEVICE_ATTR_RW(in0_crit, ina226_alert,
INA226_SHUNT_OVER_VOLTAGE_BIT);
static SENSOR_DEVICE_ATTR_RW(in0_lcrit, ina226_alert,
INA226_SHUNT_UNDER_VOLTAGE_BIT);
static SENSOR_DEVICE_ATTR_RO(in0_crit_alarm, ina226_alarm,
INA226_SHUNT_OVER_VOLTAGE_BIT);
static SENSOR_DEVICE_ATTR_RO(in0_lcrit_alarm, ina226_alarm,
INA226_SHUNT_UNDER_VOLTAGE_BIT);
/* bus voltage */
static SENSOR_DEVICE_ATTR_RO(in1_input, ina2xx_value, INA2XX_BUS_VOLTAGE);
/* bus voltage over/under voltage alert setting and alarm */
static SENSOR_DEVICE_ATTR_RW(in1_crit, ina226_alert,
INA226_BUS_OVER_VOLTAGE_BIT);
static SENSOR_DEVICE_ATTR_RW(in1_lcrit, ina226_alert,
INA226_BUS_UNDER_VOLTAGE_BIT);
static SENSOR_DEVICE_ATTR_RO(in1_crit_alarm, ina226_alarm,
INA226_BUS_OVER_VOLTAGE_BIT);
static SENSOR_DEVICE_ATTR_RO(in1_lcrit_alarm, ina226_alarm,
INA226_BUS_UNDER_VOLTAGE_BIT);
/* calculated current */
static SENSOR_DEVICE_ATTR_RO(curr1_input, ina2xx_value, INA2XX_CURRENT);
/* calculated power */
static SENSOR_DEVICE_ATTR_RO(power1_input, ina2xx_value, INA2XX_POWER);
/* over-limit power alert setting and alarm */
static SENSOR_DEVICE_ATTR_RW(power1_crit, ina226_alert,
INA226_POWER_OVER_LIMIT_BIT);
static SENSOR_DEVICE_ATTR_RO(power1_crit_alarm, ina226_alarm,
INA226_POWER_OVER_LIMIT_BIT);
/* shunt resistance */
static SENSOR_DEVICE_ATTR_RW(shunt_resistor, ina2xx_shunt, INA2XX_CALIBRATION);
@ -423,6 +596,16 @@ static const struct attribute_group ina2xx_group = {
};
static struct attribute *ina226_attrs[] = {
&sensor_dev_attr_in0_crit.dev_attr.attr,
&sensor_dev_attr_in0_lcrit.dev_attr.attr,
&sensor_dev_attr_in0_crit_alarm.dev_attr.attr,
&sensor_dev_attr_in0_lcrit_alarm.dev_attr.attr,
&sensor_dev_attr_in1_crit.dev_attr.attr,
&sensor_dev_attr_in1_lcrit.dev_attr.attr,
&sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
&sensor_dev_attr_in1_lcrit_alarm.dev_attr.attr,
&sensor_dev_attr_power1_crit.dev_attr.attr,
&sensor_dev_attr_power1_crit_alarm.dev_attr.attr,
&sensor_dev_attr_update_interval.dev_attr.attr,
NULL,
};