Fix PMIC behaviour by borrowing Electron library

PMIC initialization is now handled by the GSM init() if the selected board is suitable. The only hadcoded PMIC initialization is 500mA maximum charge current.

Author: facchinm

variants/mkrgsm1400/variant.cpp

@@ -17,6 +17,7 @@
 */
 
 #include "variant.h"
+#include "Arduino.h"
 
 const PinDescription g_APinDescription[] = {
 
@@ -172,6 +173,12 @@ SERCOM sercom5(SERCOM5);
 
 #define PMIC_ADDRESS  0x6B
 #define PMIC_REG02    0x02
+#define PMIC_REG00    0x00
+#define INPUT_CURRENT_LIMIT_0A1 (0x0)
+#define INPUT_CURRENT_LIMIT_0A9 (0x3)
+#define INPUT_CURRENT_LIMIT_1A5 (0x5)
+#define VOLTAGE_LIMIT_4V36      (0x6 << 3)
+#define VOLTAGE_LIMIT_4V04      (0x2 << 3)
 
 static inline void set_pmic_safe_defaults() {
   PERIPH_WIRE.initMasterWIRE(100000);
@@ -183,15 +190,20 @@ static inline void set_pmic_safe_defaults() {
   PERIPH_WIRE.sendDataMasterWIRE(PMIC_REG02);
   PERIPH_WIRE.sendDataMasterWIRE(0);
   PERIPH_WIRE.prepareCommandBitsWire(WIRE_MASTER_ACT_STOP);
+
   PERIPH_WIRE.disableWIRE();
 }
 
+#else
+
+static inline void set_pmic_safe_defaults() {}
+
+#endif
+
 void initVariant() {
   set_pmic_safe_defaults();
 }
 
-#endif
-
 // Serial1
 Uart Serial1(&sercom5, PIN_SERIAL1_RX, PIN_SERIAL1_TX, PAD_SERIAL1_RX, PAD_SERIAL1_TX);