[PATCH 1/4] thermal: Add new thermal trend type to support quick cooling

[Amit Daniel Kachhap <amit.kachhap@linaro.org>]

This modification adds 2 new thermal trend type THERMAL_TREND_RAISE_FULL
and THERMAL_TREND_DROP_FULL. This thermal trend can be used to quickly
jump to the upper or lower cooling level instead of incremental increase
or decrease. This is needed for temperature sensors which support rising/falling
threshold interrupts and polling can be totally avoided.

Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>
---
 drivers/thermal/step_wise.c |   19 +++++++++++++++----
 include/linux/thermal.h     |    2 ++
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
index 1242cff..0d2d8d6 100644
--- a/drivers/thermal/step_wise.c
+++ b/drivers/thermal/step_wise.c
@@ -35,6 +35,10 @@
  *       state for this trip point
  *    b. if the trend is THERMAL_TREND_DROPPING, use lower cooling
  *       state for this trip point
+ *    c. if the trend is THERMAL_TREND_RAISE_FULL, use highest cooling
+ *       state for this trip point
+ *    d. if the trend is THERMAL_TREND_DROP_FULL, use lowest cooling
+ *       state for this trip point
  */
 static unsigned long get_target_state(struct thermal_instance *instance,
 					enum thermal_trend trend)
@@ -50,7 +54,10 @@ static unsigned long get_target_state(struct thermal_instance *instance,
 	} else if (trend == THERMAL_TREND_DROPPING) {
 		cur_state = cur_state > instance->lower ?
 			    (cur_state - 1) : instance->lower;
-	}
+	} else if (trend == THERMAL_TREND_RAISE_FULL)
+		cur_state = instance->upper;
+	else if (trend == THERMAL_TREND_DROP_FULL)
+		cur_state = instance->lower;
 
 	return cur_state;
 }
@@ -87,7 +94,8 @@ static void update_instance_for_throttle(struct thermal_zone_device *tz,
 }
 
 static void update_instance_for_dethrottle(struct thermal_zone_device *tz,
-				int trip, enum thermal_trip_type trip_type)
+				int trip, enum thermal_trip_type trip_type,
+				enum thermal_trend trend)
 {
 	struct thermal_instance *instance;
 	struct thermal_cooling_device *cdev;
@@ -101,7 +109,10 @@ static void update_instance_for_dethrottle(struct thermal_zone_device *tz,
 		cdev = instance->cdev;
 		cdev->ops->get_cur_state(cdev, &cur_state);
 
-		instance->target = cur_state > instance->lower ?
+		if (trend == THERMAL_TREND_DROP_FULL)
+			instance->target = instance->lower;
+		else
+			instance->target = cur_state > instance->lower ?
 			    (cur_state - 1) : THERMAL_NO_TARGET;
 
 		/* Deactivate a passive thermal instance */
@@ -133,7 +144,7 @@ static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
 	if (tz->temperature >= trip_temp)
 		update_instance_for_throttle(tz, trip, trip_type, trend);
 	else
-		update_instance_for_dethrottle(tz, trip, trip_type);
+		update_instance_for_dethrottle(tz, trip, trip_type, trend);
 
 	mutex_unlock(&tz->lock);
 }
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index 807f214..8bce3ec 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -68,6 +68,8 @@ enum thermal_trend {
 	THERMAL_TREND_STABLE, /* temperature is stable */
 	THERMAL_TREND_RAISING, /* temperature is raising */
 	THERMAL_TREND_DROPPING, /* temperature is dropping */
+	THERMAL_TREND_RAISE_FULL, /* Apply highest cooling action*/
+	THERMAL_TREND_DROP_FULL, /* Apply lowest cooling action*/
 };
 
 /* Events supported by Thermal Netlink */
-- 
1.7.1