Adds a flag to turn the GPS power rail off entirely on tbeam

src/ButtonThread.h

@@ -5,6 +5,7 @@
 #include "configuration.h"
 #include "graphics/Screen.h"
 #include "power.h"
+#include "GPS.h"
 #include <OneButton.h>
 
 namespace concurrency
@@ -159,9 +160,21 @@ class ButtonThread : public concurrency::OSThread
 
     static void userButtonDoublePressed()
     {
-#if defined(USE_EINK) && defined(PIN_EINK_EN)
+    #if defined(USE_EINK) && defined(PIN_EINK_EN)
         digitalWrite(PIN_EINK_EN, digitalRead(PIN_EINK_EN) == LOW);
-#endif
+    #endif
+    #if defined(GPS_POWER_TOGGLE)
+        if(gps->gpsPowerflag)
+        {
+        DEBUG_MSG("Flag set to false for gps power\n");
+        } 
+        else 
+        {
+        DEBUG_MSG("Flag set to true to restore power\n");
+        }
+    gps->gpsPowerflag = !(gps->gpsPowerflag);
+    doGPSpowersave(gps->gpsPowerflag);
+    #endif
     }
 
     static void userButtonMultiPressed()

src/gps/GPS.cpp

@@ -276,7 +276,6 @@ bool GPS::setup()
     delay(10);
     digitalWrite(PIN_GPS_RESET, 0);
 #endif
-
     setAwake(true); // Wake GPS power before doing any init
     bool ok = setupGPS();
 

src/gps/GPS.h

@@ -77,6 +77,8 @@ class GPS : private concurrency::OSThread
     /// Return true if we are connected to a GPS
     bool isConnected() const { return hasGPS; }
 
+    bool gpsPowerflag; 
+
     /**
      * Restart our lock attempt - try to get and broadcast a GPS reading ASAP
      * called after the CPU wakes from light-sleep state
@@ -128,7 +130,6 @@ class GPS : private concurrency::OSThread
 
     void setNumSatellites(uint8_t n);
 
-  private:
     /// Prepare the GPS for the cpu entering deep or light sleep, expect to be gone for at least 100s of msecs
     /// always returns 0 to indicate okay to sleep
     int prepareSleep(void *unused);
@@ -136,6 +137,7 @@ class GPS : private concurrency::OSThread
     /// Prepare the GPS for the cpu entering deep sleep, expect to be gone for at least 100s of msecs
     /// always returns 0 to indicate okay to sleep
     int prepareDeepSleep(void *unused);
+  private:
 
     /**
      * Switch the GPS into a mode where we are actively looking for a lock, or alternatively switch GPS into a low power mode

src/sleep.cpp

@@ -167,6 +167,22 @@ static void waitEnterSleep()
     notifySleep.notifyObservers(NULL);
 }
 
+void doGPSpowersave(bool on)
+{
+    if (on)
+    {
+        DEBUG_MSG("Turning GPS back on\n");
+        gps->forceWake(1);
+        setGPSPower(1);
+    }
+    else
+    {
+        DEBUG_MSG("Turning off GPS chip\n");
+        notifySleep.notifyObservers(NULL);
+        setGPSPower(0);
+    }
+}
+
 void doDeepSleep(uint64_t msecToWake)
 {
     DEBUG_MSG("Entering deep sleep for %lu seconds\n", msecToWake / 1000);

src/sleep.h

@@ -13,7 +13,7 @@ esp_sleep_wakeup_cause_t doLightSleep(uint64_t msecToWake);
 extern esp_sleep_source_t wakeCause;
 #endif
 void setGPSPower(bool on);
-
+void doGPSpowersave(bool on);
 // Perform power on init that we do on each wake from deep sleep
 void initDeepSleep();
 

variants/tbeam/platformio.ini

@@ -6,4 +6,5 @@ lib_deps =
   ${esp32_base.lib_deps}
 build_flags = 
   ${esp32_base.build_flags} -D TBEAM_V10  -I variants/tbeam
+  ;-DGPS_POWER_TOGGLE ;uncomment this line to allow a double press on the user button to turn off gps entirely.
 upload_speed = 921600