ACPI: thermal: Rework thermal_get_trend()

Rework the ACPI thermal driver's .get_trend() callback function,
thermal_get_trend(), so that it does not call thermal_get_trip_type()
and thermal_get_trip_temp() which are going to be dropped.

This reduces the overhead of the function too, because it will always
carry out a trip point lookup once after the change.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index c2fe806..bd540e4 100644 (file)
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -598,46 +598,54 @@ static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
 }
 
 static int thermal_get_trend(struct thermal_zone_device *thermal,
-                            int trip, enum thermal_trend *trend)
+                            int trip_index, enum thermal_trend *trend)
 {
        struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
-       enum thermal_trip_type type;
-       int i;
+       struct acpi_thermal_trip *acpi_trip;
+       int t, i;
 
-       if (thermal_get_trip_type(thermal, trip, &type))
+       if (!tz || trip_index < 0)
                return -EINVAL;
 
-       if (type == THERMAL_TRIP_ACTIVE) {
-               int trip_temp;
-               int temp = deci_kelvin_to_millicelsius_with_offset(
-                                       tz->temperature, tz->kelvin_offset);
-               if (thermal_get_trip_temp(thermal, trip, &trip_temp))
-                       return -EINVAL;
+       if (tz->trips.critical.valid)
+               trip_index--;
+
+       if (tz->trips.hot.valid)
+               trip_index--;
+
+       if (trip_index < 0)
+               return -EINVAL;
 
-               if (temp > trip_temp) {
+       acpi_trip = &tz->trips.passive.trip;
+       if (acpi_trip->valid && !trip_index--) {
+               t = tz->trips.passive.tc1 * (tz->temperature -
+                                               tz->last_temperature) +
+                       tz->trips.passive.tc2 * (tz->temperature -
+                                               acpi_trip->temperature);
+               if (t > 0)
                        *trend = THERMAL_TREND_RAISING;
-                       return 0;
-               } else {
-                       /* Fall back on default trend */
-                       return -EINVAL;
-               }
+               else if (t < 0)
+                       *trend = THERMAL_TREND_DROPPING;
+               else
+                       *trend = THERMAL_TREND_STABLE;
+
+               return 0;
        }
 
-       /*
-        * 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.trip.temperature);
+       t = acpi_thermal_temp(tz, tz->temperature);
 
-       if (i > 0)
-               *trend = THERMAL_TREND_RAISING;
-       else if (i < 0)
-               *trend = THERMAL_TREND_DROPPING;
-       else
-               *trend = THERMAL_TREND_STABLE;
+       for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
+               acpi_trip = &tz->trips.active[i].trip;
+               if (acpi_trip->valid && !trip_index--) {
+                       if (t > acpi_thermal_temp(tz, acpi_trip->temperature)) {
+                               *trend = THERMAL_TREND_RAISING;
+                               return 0;
+                       }
+                       break;
+               }
+       }
 
-       return 0;
+       return -EINVAL;
 }
 
 static void acpi_thermal_zone_device_hot(struct thermal_zone_device *thermal)