Thermal: Introduce .get_trend() callback.
According to ACPI spec, tc1 and tc2 are used by OSPM
to anticipate the temperature trends.
We introduced the same concept to the generic thermal layer
for passive cooling, but now it seems that these values
are hard to be used on other platforms.
So We introduce .get_trend() as a more general solution.
For the platform thermal drivers that have their own way to
anticipate the temperature trends, they should provide
their own .get_trend() callback.
Or else, we will calculate the temperature trends by simply
comparing the current temperature and the cached previous
temperature reading.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Valentin, Eduardo <eduardo.valentin@ti.com>
diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
index b04fe2c..146aa04 100644
--- a/drivers/thermal/thermal_sys.c
+++ b/drivers/thermal/thermal_sys.c
@@ -723,6 +723,20 @@
struct thermal_cooling_device *cdev;
long state, max_state;
+ if (!tz->ops->get_trend ||
+ tz->ops->get_trend(tz, trip, (enum thermal_trend *)&trend)) {
+ /*
+ * compare the current temperature and previous temperature
+ * to get the thermal trend, if no special requirement
+ */
+ if (tz->temperature > tz->last_temperature)
+ trend = THERMAL_TREND_RAISING;
+ else if (tz->temperature < tz->last_temperature)
+ trend = THERMAL_TREND_DROPPING;
+ else
+ trend = THERMAL_TREND_STABLE;
+ }
+
/*
* Above Trip?
* -----------
@@ -1091,6 +1105,9 @@
goto leave;
}
+ tz->last_temperature = tz->temperature;
+ tz->temperature = temp;
+
for (count = 0; count < tz->trips; count++) {
tz->ops->get_trip_type(tz, count, &trip_type);
tz->ops->get_trip_temp(tz, count, &trip_temp);
@@ -1150,8 +1167,6 @@
thermal_zone_device_passive(tz, temp, tz->forced_passive,
THERMAL_TRIPS_NONE);
- tz->last_temperature = temp;
-
leave:
if (tz->passive)
thermal_zone_device_set_polling(tz, tz->passive_delay);