NRF52 bluetooth cleanup and fix (#3328)

* NRF52 bluetooth cleanup. Fixes BLE not returning after serial PhoneAPI connection

* Use new var name in esp32 arch

src/platform/nrf52/NRF52Bluetooth.cpp

@@ -210,8 +210,10 @@ void NRF52Bluetooth::shutdown()
 {
     // Shutdown bluetooth for minimum power draw
     LOG_INFO("Disable NRF52 bluetooth\n");
+    if (connectionHandle != 0) {
+        Bluefruit.disconnect(connectionHandle);
+    }
     Bluefruit.Advertising.stop();
-    Bluefruit.setTxPower(0); // Minimum power
 }
 
 bool NRF52Bluetooth::isConnected()
@@ -289,6 +291,14 @@ void NRF52Bluetooth::setup()
     }
 }
 
+void NRF52Bluetooth::resumeAdverising()
+{
+    Bluefruit.Advertising.restartOnDisconnect(true);
+    Bluefruit.Advertising.setInterval(32, 244); // in unit of 0.625 ms
+    Bluefruit.Advertising.setFastTimeout(30);   // number of seconds in fast mode
+    Bluefruit.Advertising.start(0);
+}
+
 /// Given a level between 0-100, update the BLE attribute
 void updateBatteryLevel(uint8_t level)
 {

src/platform/nrf52/NRF52Bluetooth.h

@@ -8,6 +8,7 @@ class NRF52Bluetooth : BluetoothApi
   public:
     void setup();
     void shutdown();
+    void resumeAdverising();
     void clearBonds();
     bool isConnected();
     int getRssi();
@@ -17,4 +18,4 @@ class NRF52Bluetooth : BluetoothApi
     void convertToUint8(uint8_t target[4], uint32_t source);
     static bool onPairingPasskey(uint16_t conn_handle, uint8_t const passkey[6], bool match_request);
     static void onPairingCompleted(uint16_t conn_handle, uint8_t auth_status);
-};
+};

src/platform/nrf52/main-nrf52.cpp

@@ -63,28 +63,29 @@ static void initBrownout()
     // We don't bother with setting up brownout if soft device is disabled - because during production we always use softdevice
 }
 
-static bool bleOn = false;
 static const bool useSoftDevice = true; // Set to false for easier debugging
 
-void setBluetoothEnable(bool on)
+void setBluetoothEnable(bool enable)
 {
-    if (on != bleOn && config.bluetooth.enabled == true) {
-        if (on) {
+    if (enable && config.bluetooth.enabled) {
+        if (!useSoftDevice) {
+            LOG_INFO("DISABLING NRF52 BLUETOOTH WHILE DEBUGGING\n");
+        } else {
             if (!nrf52Bluetooth) {
-                if (!useSoftDevice)
-                    LOG_INFO("DISABLING NRF52 BLUETOOTH WHILE DEBUGGING\n");
-                else {
-                    nrf52Bluetooth = new NRF52Bluetooth();
-                    nrf52Bluetooth->setup();
+                LOG_DEBUG("Initializing NRF52 Bluetooth\n");
+                nrf52Bluetooth = new NRF52Bluetooth();
+                nrf52Bluetooth->setup();
 
-                    // We delay brownout init until after BLE because BLE starts soft device
-                    initBrownout();
-                }
+                // We delay brownout init until after BLE because BLE starts soft device
+                initBrownout();
+            } else {
+                nrf52Bluetooth->resumeAdverising();
             }
-        } else if (nrf52Bluetooth) {
+        }
+    } else {
+        if (nrf52Bluetooth) {
             nrf52Bluetooth->shutdown();
         }
-        bleOn = on;
     }
 }