Commit 26bb0e9a authored Sep 24, 2014 by Lukasz Majewski Committed by Zhang Rui Oct 09, 2014

thermal: step_wise: fix: Prevent from binary overflow when trend is dropping

It turns out that some boards can have instance->lower greater than 0 and
when thermal trend is dropping it results with next_target equal to -1.

Since the next_target is defined as unsigned long it is interpreted as
0xFFFFFFFF and larger than instance->upper.
As a result the next_target is set to instance->upper which ramps up to
maximal cooling device target when the temperature is steadily decreasing.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

parent 52addcf9

drivers/thermal/step_wise.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -76,7 +76,7 @@ static unsigned long get_target_state(struct thermal_instance *instance,
		next_target = instance->upper;
		break;
		case THERMAL_TREND_DROPPING:
		if (cur_state == instance->lower) {
		if (cur_state <= instance->lower) {
		if (!throttle)
		next_target = THERMAL_NO_TARGET;
		} else {