Deduplicate DC/DC regulator enable for NRF52 boards

Some NRF52 boards are able to use the internal power-efficient DC/DC
regulator. Add a new class that can be inherited by board classes to
enable this feature and reduce the power consumption.

Signed-off-by: Frieder Schrempf <frieder@fris.de>

src/helpers/NRF52Board.cpp

@@ -1,6 +1,23 @@
 #if defined(NRF52_PLATFORM)
 #include "NRF52Board.h"
 
+void NRF52Board::begin() {
+  startup_reason = BD_STARTUP_NORMAL;
+}
+
+void NRF52BoardDCDC::begin() {
+  NRF52Board::begin();
+
+  // Enable DC/DC converter for improved power efficiency
+  uint8_t sd_enabled = 0;
+  sd_softdevice_is_enabled(&sd_enabled);
+  if (sd_enabled) {
+    sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);
+  } else {
+    NRF_POWER->DCDCEN = 1;
+  }
+}
+
 // Temperature from NRF52 MCU
 float NRF52Board::getMCUTemperature() {
   NRF_TEMP->TASKS_START = 1; // Start temperature measurement

src/helpers/NRF52Board.h

@@ -10,9 +10,21 @@ protected:
   uint8_t startup_reason;
 
 public:
-  virtual void begin() { startup_reason = BD_STARTUP_NORMAL; }
+  virtual void begin();
   virtual uint8_t getStartupReason() const override { return startup_reason; }
   float getMCUTemperature() override;
   virtual void reboot() override { NVIC_SystemReset(); }
 };
+
+/*
+ * The NRF52 has an internal DC/DC regulator that allows increased efficiency
+ * compared to the LDO regulator. For being able to use it, the module/board
+ * needs to have the required inductors and and capacitors populated. If the
+ * hardware requirements are met, this subclass can be used to enable the DC/DC
+ * regulator.
+ */
+class NRF52BoardDCDC : virtual public NRF52Board {
+public:
+  virtual void begin() override;
+};
 #endif

variants/rak_wismesh_tag/RAKWismeshTagBoard.cpp

@@ -19,16 +19,7 @@ static void disconnect_callback(uint16_t conn_handle, uint8_t reason) {
 }
 
 void RAKWismeshTagBoard::begin() {
-  NRF52Board::begin();
-
-  // Enable DC/DC converter for improved power efficiency
-  uint8_t sd_enabled = 0;
-  sd_softdevice_is_enabled(&sd_enabled);
-  if (sd_enabled) {
-    sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);
-  } else {
-    NRF_POWER->DCDCEN = 1;
-  }
+  NRF52BoardDCDC::begin();
 
   pinMode(PIN_VBAT_READ, INPUT);
   pinMode(PIN_USER_BTN, INPUT_PULLUP);

variants/rak_wismesh_tag/RAKWismeshTagBoard.h

@@ -8,7 +8,7 @@
 #define  PIN_VBAT_READ    5
 #define  ADC_MULTIPLIER   (3 * 1.73 * 1.187 * 1000)
 
-class RAKWismeshTagBoard : public NRF52Board {
+class RAKWismeshTagBoard : public NRF52BoardDCDC {
 public:
   void begin();
 

variants/t1000-e/T1000eBoard.cpp

@@ -5,18 +5,9 @@
 #include <bluefruit.h>
 
 void T1000eBoard::begin() {
-  NRF52Board::begin();
+  NRF52BoardDCDC::begin();
   btn_prev_state = HIGH;
 
-  // Enable DC/DC converter for improved power efficiency
-  uint8_t sd_enabled = 0;
-  sd_softdevice_is_enabled(&sd_enabled);
-  if (sd_enabled) {
-    sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);
-  } else {
-    NRF_POWER->DCDCEN = 1;
-  }
-
 #ifdef BUTTON_PIN
   pinMode(BATTERY_PIN, INPUT);
   pinMode(BUTTON_PIN, INPUT);

variants/t1000-e/T1000eBoard.h

@@ -4,7 +4,7 @@
 #include <Arduino.h>
 #include <helpers/NRF52Board.h>
 
-class T1000eBoard : public NRF52Board {
+class T1000eBoard : public NRF52BoardDCDC {
 protected:
   uint8_t btn_prev_state;
 

variants/wio-tracker-l1/WioTrackerL1Board.cpp

@@ -19,18 +19,9 @@ static void disconnect_callback(uint16_t conn_handle, uint8_t reason) {
 }
 
 void WioTrackerL1Board::begin() {
-  NRF52Board::begin();
+  NRF52BoardDCDC::begin();
   btn_prev_state = HIGH;
 
-  // Enable DC/DC converter for improved power efficiency
-  uint8_t sd_enabled = 0;
-  sd_softdevice_is_enabled(&sd_enabled);
-  if (sd_enabled) {
-    sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);
-  } else {
-    NRF_POWER->DCDCEN = 1;
-  }
-
   pinMode(PIN_VBAT_READ, INPUT); // VBAT ADC input
   // Set all button pins to INPUT_PULLUP
   pinMode(PIN_BUTTON1, INPUT_PULLUP);

variants/wio-tracker-l1/WioTrackerL1Board.h

@@ -4,7 +4,7 @@
 #include <Arduino.h>
 #include <helpers/NRF52Board.h>
 
-class WioTrackerL1Board : public NRF52Board {
+class WioTrackerL1Board : public NRF52BoardDCDC {
 protected:
   uint8_t btn_prev_state;
 

variants/wio_wm1110/WioWM1110Board.cpp

@@ -21,16 +21,7 @@ static void disconnect_callback(uint16_t conn_handle, uint8_t reason) {
 }
 
 void WioWM1110Board::begin() {
-  NRF52Board::begin();
-
-  // Enable DC/DC converter for improved power efficiency
-  uint8_t sd_enabled = 0;
-  sd_softdevice_is_enabled(&sd_enabled);
-  if (sd_enabled) {
-    sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);
-  } else {
-    NRF_POWER->DCDCEN = 1;
-  }
+  NRF52BoardDCDC::begin();
 
   pinMode(BATTERY_PIN, INPUT);
   pinMode(LED_GREEN, OUTPUT);

variants/wio_wm1110/WioWM1110Board.h

@@ -11,7 +11,7 @@
 #endif
 #define Serial Serial1
 
-class WioWM1110Board : public NRF52Board {
+class WioWM1110Board : public NRF52BoardDCDC {
 public:
   void begin();
 

variants/xiao_nrf52/XiaoNrf52Board.cpp

@@ -21,16 +21,7 @@ static void disconnect_callback(uint16_t conn_handle, uint8_t reason) {
 }
 
 void XiaoNrf52Board::begin() {
-  NRF52Board::begin();
-
-  // Enable DC/DC converter for improved power efficiency
-  uint8_t sd_enabled = 0;
-  sd_softdevice_is_enabled(&sd_enabled);
-  if (sd_enabled) {
-    sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE);
-  } else {
-    NRF_POWER->DCDCEN = 1;
-  }
+  NRF52BoardDCDC::begin();
 
   pinMode(PIN_VBAT, INPUT);
   pinMode(VBAT_ENABLE, OUTPUT);

variants/xiao_nrf52/XiaoNrf52Board.h

@@ -6,7 +6,7 @@
 
 #ifdef XIAO_NRF52
 
-class XiaoNrf52Board : public NRF52Board {
+class XiaoNrf52Board : public NRF52BoardDCDC {
 public:
   void begin();