Allow override of deviation with absolute minimum RPM

If the devation is less than zero, treat as an absolute minimum RPM value

1 files changed, 21 insertions, 11 deletions

diff --git a/monitor/fan.cpp b/monitor/fan.cpp
index 39b32bb..e608d76 100644
--- a/monitor/fan.cpp
+++ b/monitor/fan.cpp
@@ -36,7 +36,8 @@ Fan::Fan(Mode mode,
          const FanDefinition& def) :
     _bus(bus),
     _name(std::get<fanNameField>(def)),
-    _deviation(std::get<fanDeviationField>(def)),
+    _deviation((std::get<fanDeviationField>(def) < 0)?abs(std::get<fanDeviationField>(def)):std::get<fanDeviationField>(def)),
+    _deviationIsMinRPM((std::get<fanDeviationField>(def) < 0)?true:false),
     _numSensorFailsForNonFunc(std::get<numSensorFailsForNonfuncField>(def)),
     _trustManager(trust)
 {
@@ -168,17 +169,26 @@ bool Fan::outOfRange(const TachSensor& sensor)
     auto factor = sensor.getFactor();
     auto offset = sensor.getOffset();
 
-    uint64_t min = target * (100 - _deviation) / 100;
-    uint64_t max = target * (100 + _deviation) / 100;
-
-    // TODO: openbmc/openbmc#2937 enhance this function
-    // either by making it virtual, or by predefining different
-    // outOfRange ops and selecting by yaml config
-    min = min * factor + offset;
-    max = max * factor + offset;
-    if ((actual < min) || (actual > max))
+    if (_deviationIsMinRPM)
     {
-        return true;
+        if (actual < _deviation)
+        {
+            return true;
+        }
+    }
+    else {
+        uint64_t min = target * (100 - _deviation) / 100;
+        uint64_t max = target * (100 + _deviation) / 100;
+
+        // TODO: openbmc/openbmc#2937 enhance this function
+        // either by making it virtual, or by predefining different
+        // outOfRange ops and selecting by yaml config
+        min = min * factor + offset;
+        max = max * factor + offset;
+        if ((actual < min) || (actual > max))
+        {
+            return true;
+        }
     }
 
     return false;