progress on keeping gps off more

src/GPS.h

@@ -3,6 +3,7 @@
 #include <TinyGPS++.h>
 #include "PeriodicTask.h"
 #include "Observer.h"
+#include "sys/time.h"
 
 /**
  * A gps class that only reads from the GPS periodically (and FIXME - eventually keeps the gps powered down except when reading)
@@ -14,8 +15,11 @@ class GPS : public PeriodicTask, public Observable, public TinyGPSPlus
 public:
     GPS();
 
-    /// Return time since 1970 in msecs.  Until we have a GPS lock we will be returning time based at zero
-    uint64_t getTime();
+    /// Return time since 1970 in secs.  Until we have a GPS lock we will be returning time based at zero
+    uint32_t getTime();
+
+    /// Return time since 1970 in secs.  If we don't have a GPS lock return zero
+    uint32_t getValidTime();
 
     String getTimeStr();
 
@@ -25,6 +29,9 @@ public:
 
     virtual void doTask();
 
+    /// If we haven't yet set our RTC this boot, set it from a GPS derived time
+    void perhapsSetRTC(const struct timeval *tv);
+
 private:
     void readFromRTC();
 };