ESP32-PaxCounter/src/power.cpp

// Basic config
#include "globals.h"
#include "power.h"

// Local logging tag
static const char TAG[] = __FILE__;

#ifdef HAS_PMU

AXP20X_Class axp;

void AXP192_init(void) {
  
  if (axp.begin(Wire, AXP192_PRIMARY_ADDRESS))
    ESP_LOGI(TAG, "AXP192 PMU initialization failed");
  else {

    axp.setPowerOutPut(AXP192_LDO2, AXP202_ON);
    axp.setPowerOutPut(AXP192_LDO3, AXP202_ON);
    axp.setPowerOutPut(AXP192_DCDC2, AXP202_ON);
    axp.setPowerOutPut(AXP192_EXTEN, AXP202_ON);
    axp.setPowerOutPut(AXP192_DCDC1, AXP202_ON);
    axp.setDCDC1Voltage(3300);
    axp.setChgLEDMode(AXP20X_LED_BLINK_1HZ);
    // axp.setChgLEDMode(AXP20X_LED_OFF);
    axp.adc1Enable(AXP202_BATT_CUR_ADC1, 1);

#ifdef PMU_INT
    pinMode(PMU_INT, INPUT_PULLUP);
    attachInterrupt(digitalPinToInterrupt(PMU_INT),
                    [] {
                      ESP_LOGI(TAG, "Power source changed");
                      /* put your code here */
                    },
                    FALLING);
    axp.enableIRQ(AXP202_VBUS_REMOVED_IRQ | AXP202_VBUS_CONNECT_IRQ |
                      AXP202_BATT_REMOVED_IRQ | AXP202_BATT_CONNECT_IRQ,
                  1);
    axp.clearIRQ();
#endif // PMU_INT

    ESP_LOGI(TAG, "AXP192 PMU initialized.");
  }
}
#endif // HAS_PMU

#ifdef BAT_MEASURE_ADC
esp_adc_cal_characteristics_t *adc_characs =
    (esp_adc_cal_characteristics_t *)calloc(
        1, sizeof(esp_adc_cal_characteristics_t));

static const adc1_channel_t adc_channel = BAT_MEASURE_ADC;
static const adc_atten_t atten = ADC_ATTEN_DB_11;
static const adc_unit_t unit = ADC_UNIT_1;
#endif

void calibrate_voltage(void) {
#ifdef BAT_MEASURE_ADC
  // configure ADC
  ESP_ERROR_CHECK(adc1_config_width(ADC_WIDTH_BIT_12));
  ESP_ERROR_CHECK(adc1_config_channel_atten(adc_channel, atten));
  // calibrate ADC
  esp_adc_cal_value_t val_type = esp_adc_cal_characterize(
      unit, atten, ADC_WIDTH_BIT_12, DEFAULT_VREF, adc_characs);
  // show ADC characterization base
  if (val_type == ESP_ADC_CAL_VAL_EFUSE_TP) {
    ESP_LOGI(TAG,
             "ADC characterization based on Two Point values stored in eFuse");
  } else if (val_type == ESP_ADC_CAL_VAL_EFUSE_VREF) {
    ESP_LOGI(TAG,
             "ADC characterization based on reference voltage stored in eFuse");
  } else {
    ESP_LOGI(TAG, "ADC characterization based on default reference voltage");
  }
#endif
}


uint8_t getBattLevel() {
  /*
  return values:
  MCMD_DEVS_EXT_POWER   = 0x00, // external power supply
  MCMD_DEVS_BATT_MIN    = 0x01, // min battery value
  MCMD_DEVS_BATT_MAX    = 0xFE, // max battery value
  MCMD_DEVS_BATT_NOINFO = 0xFF, // unknown battery level
  */
#if (defined HAS_PMU || defined BAT_MEASURE_ADC)
  uint16_t voltage = read_voltage();

  switch (voltage) {
  case 0:
    return MCMD_DEVS_BATT_NOINFO;
  case 0xffff:
    return MCMD_DEVS_EXT_POWER;
  default:
    return (voltage > OTA_MIN_BATT ? MCMD_DEVS_BATT_MAX : MCMD_DEVS_BATT_MIN);
  }
#else // we don't have any info on battery level
  return MCMD_DEVS_BATT_NOINFO;
#endif
} // getBattLevel()

// u1_t os_getBattLevel(void) { return getBattLevel(); };


uint16_t read_voltage() {

  uint16_t voltage = 0;

#ifdef HAS_PMU
  voltage = axp.isVBUSPlug() ? 0xffff : axp.getBattVoltage();
#else

#ifdef BAT_MEASURE_ADC
  // multisample ADC
  uint32_t adc_reading = 0;
  for (int i = 0; i < NO_OF_SAMPLES; i++) {
    adc_reading += adc1_get_raw(adc_channel);
  }
  adc_reading /= NO_OF_SAMPLES;
  // Convert ADC reading to voltage in mV
  voltage = esp_adc_cal_raw_to_voltage(adc_reading, adc_characs);
#endif

#ifdef BAT_VOLTAGE_DIVIDER
  voltage *= BAT_VOLTAGE_DIVIDER;
#endif

#endif // HAS_PMU

  return voltage;
}