hwmon: (max6650) Add support for alarms
Export the alarm flags provided by the MAX6650/MAX6651 fan-speed regulator
and monitor chips via sysfs.
Signed-off-by: Christian Engelmayer <christian.engelmayer@frequentis.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c
index f27af6a..86142a8 100644
--- a/drivers/hwmon/max6650.c
+++ b/drivers/hwmon/max6650.c
@@ -12,7 +12,7 @@
* also work with the MAX6651. It does not distinguish max6650 and max6651
* chips.
*
- * Tha datasheet was last seen at:
+ * The datasheet was last seen at:
*
* http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
*
@@ -98,6 +98,16 @@
#define MAX6650_CFG_MODE_OPEN_LOOP 0x30
#define MAX6650_COUNT_MASK 0x03
+/*
+ * Alarm status register bits
+ */
+
+#define MAX6650_ALRM_MAX 0x01
+#define MAX6650_ALRM_MIN 0x02
+#define MAX6650_ALRM_TACH 0x04
+#define MAX6650_ALRM_GPIO1 0x08
+#define MAX6650_ALRM_GPIO2 0x10
+
/* Minimum and maximum values of the FAN-RPM */
#define FAN_RPM_MIN 240
#define FAN_RPM_MAX 30000
@@ -151,6 +161,7 @@
u8 tach[4];
u8 count;
u8 dac;
+ u8 alarm;
};
static ssize_t get_fan(struct device *dev, struct device_attribute *devattr,
@@ -418,6 +429,33 @@
return count;
}
+/*
+ * Get alarm stati:
+ * Possible values:
+ * 0 = no alarm
+ * 1 = alarm
+ */
+
+static ssize_t get_alarm(struct device *dev, struct device_attribute *devattr,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+ struct max6650_data *data = max6650_update_device(dev);
+ struct i2c_client *client = to_i2c_client(dev);
+ int alarm = 0;
+
+ if (data->alarm & attr->index) {
+ mutex_lock(&data->update_lock);
+ alarm = 1;
+ data->alarm &= ~attr->index;
+ data->alarm |= i2c_smbus_read_byte_data(client,
+ MAX6650_REG_ALARM);
+ mutex_unlock(&data->update_lock);
+ }
+
+ return sprintf(buf, "%d\n", alarm);
+}
+
static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan, NULL, 0);
static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, get_fan, NULL, 1);
static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, get_fan, NULL, 2);
@@ -426,7 +464,41 @@
static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_div, set_div);
static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, get_enable, set_enable);
static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm);
+static SENSOR_DEVICE_ATTR(fan1_max_alarm, S_IRUGO, get_alarm, NULL,
+ MAX6650_ALRM_MAX);
+static SENSOR_DEVICE_ATTR(fan1_min_alarm, S_IRUGO, get_alarm, NULL,
+ MAX6650_ALRM_MIN);
+static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, get_alarm, NULL,
+ MAX6650_ALRM_TACH);
+static SENSOR_DEVICE_ATTR(gpio1_alarm, S_IRUGO, get_alarm, NULL,
+ MAX6650_ALRM_GPIO1);
+static SENSOR_DEVICE_ATTR(gpio2_alarm, S_IRUGO, get_alarm, NULL,
+ MAX6650_ALRM_GPIO2);
+static mode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
+ int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct i2c_client *client = to_i2c_client(dev);
+ u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
+ struct device_attribute *devattr;
+
+ /*
+ * Hide the alarms that have not been enabled by the firmware
+ */
+
+ devattr = container_of(a, struct device_attribute, attr);
+ if (devattr == &sensor_dev_attr_fan1_max_alarm.dev_attr
+ || devattr == &sensor_dev_attr_fan1_min_alarm.dev_attr
+ || devattr == &sensor_dev_attr_fan1_fault.dev_attr
+ || devattr == &sensor_dev_attr_gpio1_alarm.dev_attr
+ || devattr == &sensor_dev_attr_gpio2_alarm.dev_attr) {
+ if (!(alarm_en & to_sensor_dev_attr(devattr)->index))
+ return 0;
+ }
+
+ return a->mode;
+}
static struct attribute *max6650_attrs[] = {
&sensor_dev_attr_fan1_input.dev_attr.attr,
@@ -437,11 +509,17 @@
&dev_attr_fan1_div.attr,
&dev_attr_pwm1_enable.attr,
&dev_attr_pwm1.attr,
+ &sensor_dev_attr_fan1_max_alarm.dev_attr.attr,
+ &sensor_dev_attr_fan1_min_alarm.dev_attr.attr,
+ &sensor_dev_attr_fan1_fault.dev_attr.attr,
+ &sensor_dev_attr_gpio1_alarm.dev_attr.attr,
+ &sensor_dev_attr_gpio2_alarm.dev_attr.attr,
NULL
};
static struct attribute_group max6650_attr_grp = {
.attrs = max6650_attrs,
+ .is_visible = max6650_attrs_visible,
};
/*
@@ -659,6 +737,12 @@
MAX6650_REG_COUNT);
data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC);
+ /* Alarms are cleared on read in case the condition that
+ * caused the alarm is removed. Keep the value latched here
+ * for providing the register through different alarm files. */
+ data->alarm |= i2c_smbus_read_byte_data(client,
+ MAX6650_REG_ALARM);
+
data->last_updated = jiffies;
data->valid = 1;
}