Thermal: Introduce .get_trend() callback.

[firefly-linux-kernel-4.4.55.git] / drivers / acpi / thermal.c

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index d7ef69d835f2197fd1d520a65140587685468b8c..bb95709a6be8c3a16ce25acfebe490e48d588c0a 100644 (file)
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -706,6 +706,38 @@ static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
                return -EINVAL;
 }
 
+static int thermal_get_trend(struct thermal_zone_device *thermal,
+                               int trip, enum thermal_trend *trend)
+{
+       struct acpi_thermal *tz = thermal->devdata;
+       enum thermal_trip_type type;
+       int i;
+
+       if (thermal_get_trip_type(thermal, trip, &type))
+               return -EINVAL;
+
+       /* Only PASSIVE trip points need TREND */
+       if (type != THERMAL_TRIP_PASSIVE)
+               return -EINVAL;
+
+       /*
+        * tz->temperature has already been updated by generic thermal layer,
+        * before this callback being invoked
+        */
+       i = (tz->trips.passive.tc1 * (tz->temperature - tz->last_temperature))
+               + (tz->trips.passive.tc2
+               * (tz->temperature - tz->trips.passive.temperature));
+
+       if (i > 0)
+               *trend = THERMAL_TREND_RAISING;
+       else if (i < 0)
+               *trend = THERMAL_TREND_DROPPING;
+       else
+               *trend = THERMAL_TREND_STABLE;
+       return 0;
+}
+
+
 static int thermal_notify(struct thermal_zone_device *thermal, int trip,
                           enum thermal_trip_type trip_type)
 {
@@ -838,6 +870,7 @@ static const struct thermal_zone_device_ops acpi_thermal_zone_ops = {
        .get_trip_type = thermal_get_trip_type,
        .get_trip_temp = thermal_get_trip_temp,
        .get_crit_temp = thermal_get_crit_temp,
+       .get_trend = thermal_get_trend,
        .notify = thermal_notify,
 };