mlxsw: core_hwmon: Extend hwmon interface with critical and emergency alarms

Add new attributes to hwmon object for exposing critical and emergency
alarms.

In case that current temperature is higher than emergency threshold,
EMERGENCY alarm will be reported in sensors utility:

$ sensors
...
front panel 025:  +55.0°C  (crit = +35.0°C, emerg = +40.0°C) ALARM(EMERGENCY)

In case that current temperature is higher than critical threshold,
CRIT alarm will be reported in sensors utility:

$ sensors
...
front panel 025:  +54.0°C  (crit = +35.0°C, emerg = +80.0°C) ALARM(CRIT)
Signed-off-by: Amit Cohen <amitc@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Acked-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/core_hwmon.c

@@ -17,7 +17,7 @@
 #define MLXSW_HWMON_GEARBOXES_MAX_COUNT 32
 
 #define MLXSW_HWMON_ATTR_PER_SENSOR 3
-#define MLXSW_HWMON_ATTR_PER_MODULE 5
+#define MLXSW_HWMON_ATTR_PER_MODULE 7
 #define MLXSW_HWMON_ATTR_PER_GEARBOX 4
 
 #define MLXSW_HWMON_ATTR_COUNT (MLXSW_HWMON_SENSORS_MAX_COUNT * MLXSW_HWMON_ATTR_PER_SENSOR + \
@@ -388,6 +388,53 @@ mlxsw_hwmon_gbox_temp_label_show(struct device *dev,
 	return sprintf(buf, "gearbox %03u\n", index);
 }
 
+static ssize_t mlxsw_hwmon_temp_critical_alarm_show(struct device *dev,
+						    struct device_attribute *attr,
+						    char *buf)
+{
+	int err, temp, emergency_temp, critic_temp;
+
+	err = mlxsw_hwmon_module_temp_get(dev, attr, &temp);
+	if (err)
+		return err;
+
+	if (temp <= 0)
+		return sprintf(buf, "%d\n", false);
+
+	err = mlxsw_hwmon_module_temp_emergency_get(dev, attr, &emergency_temp);
+	if (err)
+		return err;
+
+	if (temp >= emergency_temp)
+		return sprintf(buf, "%d\n", false);
+
+	err = mlxsw_hwmon_module_temp_critical_get(dev, attr, &critic_temp);
+	if (err)
+		return err;
+
+	return sprintf(buf, "%d\n", temp >= critic_temp);
+}
+
+static ssize_t mlxsw_hwmon_temp_emergency_alarm_show(struct device *dev,
+						     struct device_attribute *attr,
+						     char *buf)
+{
+	int err, temp, emergency_temp;
+
+	err = mlxsw_hwmon_module_temp_get(dev, attr, &temp);
+	if (err)
+		return err;
+
+	if (temp <= 0)
+		return sprintf(buf, "%d\n", false);
+
+	err = mlxsw_hwmon_module_temp_emergency_get(dev, attr, &emergency_temp);
+	if (err)
+		return err;
+
+	return sprintf(buf, "%d\n", temp >= emergency_temp);
+}
+
 enum mlxsw_hwmon_attr_type {
 	MLXSW_HWMON_ATTR_TYPE_TEMP,
 	MLXSW_HWMON_ATTR_TYPE_TEMP_MAX,
@@ -401,6 +448,8 @@ enum mlxsw_hwmon_attr_type {
 	MLXSW_HWMON_ATTR_TYPE_TEMP_MODULE_EMERG,
 	MLXSW_HWMON_ATTR_TYPE_TEMP_MODULE_LABEL,
 	MLXSW_HWMON_ATTR_TYPE_TEMP_GBOX_LABEL,
+	MLXSW_HWMON_ATTR_TYPE_TEMP_CRIT_ALARM,
+	MLXSW_HWMON_ATTR_TYPE_TEMP_EMERGENCY_ALARM,
 };
 
 static void mlxsw_hwmon_attr_add(struct mlxsw_hwmon *mlxsw_hwmon,
@@ -491,6 +540,20 @@ static void mlxsw_hwmon_attr_add(struct mlxsw_hwmon *mlxsw_hwmon,
 		snprintf(mlxsw_hwmon_attr->name, sizeof(mlxsw_hwmon_attr->name),
 			 "temp%u_label", num + 1);
 		break;
+	case MLXSW_HWMON_ATTR_TYPE_TEMP_CRIT_ALARM:
+		mlxsw_hwmon_attr->dev_attr.show =
+			mlxsw_hwmon_temp_critical_alarm_show;
+		mlxsw_hwmon_attr->dev_attr.attr.mode = 0444;
+		snprintf(mlxsw_hwmon_attr->name, sizeof(mlxsw_hwmon_attr->name),
+			 "temp%u_crit_alarm", num + 1);
+		break;
+	case MLXSW_HWMON_ATTR_TYPE_TEMP_EMERGENCY_ALARM:
+		mlxsw_hwmon_attr->dev_attr.show =
+			mlxsw_hwmon_temp_emergency_alarm_show;
+		mlxsw_hwmon_attr->dev_attr.attr.mode = 0444;
+		snprintf(mlxsw_hwmon_attr->name, sizeof(mlxsw_hwmon_attr->name),
+			 "temp%u_emergency_alarm", num + 1);
+		break;
 	default:
 		WARN_ON(1);
 	}
@@ -613,6 +676,12 @@ static int mlxsw_hwmon_module_init(struct mlxsw_hwmon *mlxsw_hwmon)
 		mlxsw_hwmon_attr_add(mlxsw_hwmon,
 				     MLXSW_HWMON_ATTR_TYPE_TEMP_MODULE_LABEL,
 				     i, i);
+		mlxsw_hwmon_attr_add(mlxsw_hwmon,
+				     MLXSW_HWMON_ATTR_TYPE_TEMP_CRIT_ALARM,
+				     i, i);
+		mlxsw_hwmon_attr_add(mlxsw_hwmon,
+				     MLXSW_HWMON_ATTR_TYPE_TEMP_EMERGENCY_ALARM,
+				     i, i);
 	}
 
 	return 0;