cleanup on distance method logic

Author: gigapod

src/sfTk/sfDevXM125Presence.cpp

@@ -94,26 +94,26 @@ sfTkError_t sfDevXM125Presence::getPresenceDistanceValuemm(uint32_t &presenceVal
 
     sfTkError_t retVal = getPresenceDetectorErrorStatus(errorStatus);
     if (retVal != ksfTkErrOk || errorStatus != 0)
-        return 1;
+        return sfTkErrFail;
 
     // Start detector
     if (setPresenceCommand(SFE_XM125_PRESENCE_START_DETECTOR) != ksfTkErrOk)
-        return 2;
+        return sfTkErrFail;
 
     sftk_delay_ms(100);
 
-    // Poll detector status until busy bit is cleared - CHECK ON THIS!
+    // Poll detector status until busy bit is cleared
     if (presenceBusyWait() != ksfTkErrOk)
-        return 3;
+        return sfTkErrFail;
 
     // Verify that no error bits are set in the detector status register
     retVal = getPresenceDetectorErrorStatus(errorStatus);
     if (retVal != ksfTkErrOk || errorStatus != 0)
-        return 4;
+        return sfTkErrFail;
 
     // Read from 16-Bit Register to get the presence detection status
     if (_theBus->readRegister(SFE_XM125_PRESENCE_RESULT, presenceStatus) != ksfTkErrOk)
-        return 5;
+        return sfTkErrFail;
 
     // Presence detected NOW or since last check (sticky)
     bool bPresenceDetected = ((presenceStatus & SFE_XM125_PRESENCE_DETECTED_MASK) != 0) ||
@@ -123,6 +123,8 @@ sfTkError_t sfDevXM125Presence::getPresenceDistanceValuemm(uint32_t &presenceVal
     if (bPresenceDetected)
         return getPresenceDistance(presenceVal);
 
+    // If no presence detected, return 0
+    presenceVal = 0;
     return ksfTkErrOk;
 }