diff --git a/drivers/hwmon/nct7802.c b/drivers/hwmon/nct7802.c
index 7915c2f2c85d..2e97e56c72c7 100644
--- a/drivers/hwmon/nct7802.c
+++ b/drivers/hwmon/nct7802.c
@@ -58,6 +58,8 @@ static const u8 REG_VOLTAGE_LIMIT_MSB_SHIFT[2][5] = {
 struct nct7802_data {
 	struct regmap *regmap;
 	struct mutex access_lock; /* for multi-byte read and write operations */
+	u8 in_status;
+	struct mutex in_alarm_lock;
 };
 
 static ssize_t temp_type_show(struct device *dev,
@@ -368,6 +370,66 @@ static ssize_t in_store(struct device *dev, struct device_attribute *attr,
 	return err ? : count;
 }
 
+static ssize_t in_alarm_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
+	struct nct7802_data *data = dev_get_drvdata(dev);
+	int volt, min, max, ret;
+	unsigned int val;
+
+	mutex_lock(&data->in_alarm_lock);
+
+	/*
+	 * The SMI Voltage status register is the only register giving a status
+	 * for voltages. A bit is set for each input crossing a threshold, in
+	 * both direction, but the "inside" or "outside" limits info is not
+	 * available. Also this register is cleared on read.
+	 * Note: this is not explicitly spelled out in the datasheet, but
+	 * from experiment.
+	 * To deal with this we use a status cache with one validity bit and
+	 * one status bit for each input. Validity is cleared at startup and
+	 * each time the register reports a change, and the status is processed
+	 * by software based on current input value and limits.
+	 */
+	ret = regmap_read(data->regmap, 0x1e, &val); /* SMI Voltage status */
+	if (ret < 0)
+		goto abort;
+
+	/* invalidate cached status for all inputs crossing a threshold */
+	data->in_status &= ~((val & 0x0f) << 4);
+
+	/* if cached status for requested input is invalid, update it */
+	if (!(data->in_status & (0x10 << sattr->index))) {
+		ret = nct7802_read_voltage(data, sattr->nr, 0);
+		if (ret < 0)
+			goto abort;
+		volt = ret;
+
+		ret = nct7802_read_voltage(data, sattr->nr, 1);
+		if (ret < 0)
+			goto abort;
+		min = ret;
+
+		ret = nct7802_read_voltage(data, sattr->nr, 2);
+		if (ret < 0)
+			goto abort;
+		max = ret;
+
+		if (volt < min || volt > max)
+			data->in_status |= (1 << sattr->index);
+		else
+			data->in_status &= ~(1 << sattr->index);
+
+		data->in_status |= 0x10 << sattr->index;
+	}
+
+	ret = sprintf(buf, "%u\n", !!(data->in_status & (1 << sattr->index)));
+abort:
+	mutex_unlock(&data->in_alarm_lock);
+	return ret;
+}
+
 static ssize_t temp_show(struct device *dev, struct device_attribute *attr,
 			 char *buf)
 {
@@ -660,7 +722,7 @@ static const struct attribute_group nct7802_temp_group = {
 static SENSOR_DEVICE_ATTR_2_RO(in0_input, in, 0, 0);
 static SENSOR_DEVICE_ATTR_2_RW(in0_min, in, 0, 1);
 static SENSOR_DEVICE_ATTR_2_RW(in0_max, in, 0, 2);
-static SENSOR_DEVICE_ATTR_2_RO(in0_alarm, alarm, 0x1e, 3);
+static SENSOR_DEVICE_ATTR_2_RO(in0_alarm, in_alarm, 0, 3);
 static SENSOR_DEVICE_ATTR_2_RW(in0_beep, beep, 0x5a, 3);
 
 static SENSOR_DEVICE_ATTR_2_RO(in1_input, in, 1, 0);
@@ -668,19 +730,19 @@ static SENSOR_DEVICE_ATTR_2_RO(in1_input, in, 1, 0);
 static SENSOR_DEVICE_ATTR_2_RO(in2_input, in, 2, 0);
 static SENSOR_DEVICE_ATTR_2_RW(in2_min, in, 2, 1);
 static SENSOR_DEVICE_ATTR_2_RW(in2_max, in, 2, 2);
-static SENSOR_DEVICE_ATTR_2_RO(in2_alarm, alarm, 0x1e, 0);
+static SENSOR_DEVICE_ATTR_2_RO(in2_alarm, in_alarm, 2, 0);
 static SENSOR_DEVICE_ATTR_2_RW(in2_beep, beep, 0x5a, 0);
 
 static SENSOR_DEVICE_ATTR_2_RO(in3_input, in, 3, 0);
 static SENSOR_DEVICE_ATTR_2_RW(in3_min, in, 3, 1);
 static SENSOR_DEVICE_ATTR_2_RW(in3_max, in, 3, 2);
-static SENSOR_DEVICE_ATTR_2_RO(in3_alarm, alarm, 0x1e, 1);
+static SENSOR_DEVICE_ATTR_2_RO(in3_alarm, in_alarm, 3, 1);
 static SENSOR_DEVICE_ATTR_2_RW(in3_beep, beep, 0x5a, 1);
 
 static SENSOR_DEVICE_ATTR_2_RO(in4_input, in, 4, 0);
 static SENSOR_DEVICE_ATTR_2_RW(in4_min, in, 4, 1);
 static SENSOR_DEVICE_ATTR_2_RW(in4_max, in, 4, 2);
-static SENSOR_DEVICE_ATTR_2_RO(in4_alarm, alarm, 0x1e, 2);
+static SENSOR_DEVICE_ATTR_2_RO(in4_alarm, in_alarm, 4, 2);
 static SENSOR_DEVICE_ATTR_2_RW(in4_beep, beep, 0x5a, 2);
 
 static struct attribute *nct7802_in_attrs[] = {
@@ -1011,6 +1073,7 @@ static int nct7802_probe(struct i2c_client *client,
 		return PTR_ERR(data->regmap);
 
 	mutex_init(&data->access_lock);
+	mutex_init(&data->in_alarm_lock);
 
 	ret = nct7802_init_chip(data);
 	if (ret < 0)