firmware/src/sleep.cpp

#include "configuration.h"
#include "rom/rtc.h"
#include <driver/rtc_io.h>
#include <TinyGPS++.h>
#include <Wire.h>
#include "BluetoothUtil.h"
#include "MeshBluetoothService.h"
#include "MeshService.h"
#include "GPS.h"
#include "screen.h"
#include "NodeDB.h"
#include "Periodic.h"
#include "esp32/pm.h"
#include "esp_pm.h"
#include "MeshRadio.h"
#include "main.h"
#include "sleep.h"

#ifdef T_BEAM_V10
#include "axp20x.h"
extern AXP20X_Class axp;
#endif

// deep sleep support
RTC_DATA_ATTR int bootCount = 0;
esp_sleep_source_t wakeCause; // the reason we booted this time

#define xstr(s) str(s)
#define str(s) #s

// -----------------------------------------------------------------------------
// Application
// -----------------------------------------------------------------------------

/**
 * Control CPU core speed (80MHz vs 240MHz)
 * 
 * We leave CPU at full speed during init, but once loop is called switch to low speed (for a 50% power savings)
 * 
 */
void setCPUFast(bool on)
{
  setCpuFrequencyMhz(on ? 240 : 80);
}

void setLed(bool ledOn)
{
#ifdef LED_PIN
  // toggle the led so we can get some rough sense of how often loop is pausing
  digitalWrite(LED_PIN, ledOn);
#endif

#ifdef T_BEAM_V10
  if (axp192_found)
  {
    // blink the axp led
    axp.setChgLEDMode(ledOn ? AXP20X_LED_LOW_LEVEL : AXP20X_LED_OFF);
  }
#endif
}

void setGPSPower(bool on)
{
  DEBUG_MSG("Setting GPS power=%d\n", on);

#ifdef T_BEAM_V10
  if (axp192_found)
    axp.setPowerOutPut(AXP192_LDO3, on ? AXP202_ON : AXP202_OFF); // GPS main power
#endif
}

// Perform power on init that we do on each wake from deep sleep
void initDeepSleep()
{
  bootCount++;
  wakeCause = esp_sleep_get_wakeup_cause();
  /* 
    Not using yet because we are using wake on all buttons being low

    wakeButtons = esp_sleep_get_ext1_wakeup_status();       // If one of these buttons is set it was the reason we woke
    if (wakeCause == ESP_SLEEP_WAKEUP_EXT1 && !wakeButtons) // we must have been using the 'all buttons rule for waking' to support busted boards, assume button one was pressed
        wakeButtons = ((uint64_t)1) << buttons.gpios[0];
    */

  // If we booted because our timer ran out or the user pressed reset, send those as fake events
  const char *reason = "reset"; // our best guess
  RESET_REASON hwReason = rtc_get_reset_reason(0);

  if (hwReason == RTCWDT_BROWN_OUT_RESET)
    reason = "brownout";

  if (hwReason == TG0WDT_SYS_RESET)
    reason = "taskWatchdog";

  if (hwReason == TG1WDT_SYS_RESET)
    reason = "intWatchdog";

  if (wakeCause == ESP_SLEEP_WAKEUP_TIMER)
    reason = "timeout";

  DEBUG_MSG("booted, wake cause %d (boot count %d), reset_reason=%s\n", wakeCause, bootCount, reason);
}

void doDeepSleep(uint64_t msecToWake)
{
  DEBUG_MSG("Entering deep sleep for %llu seconds\n", msecToWake / 1000);

  // not using wifi yet, but once we are this is needed to shutoff the radio hw
  // esp_wifi_stop();

  BLEDevice::deinit(false); // We are required to shutdown bluetooth before deep or light sleep

  screen.setOn(false); // datasheet says this will draw only 10ua

  // Put radio in sleep mode (will still draw power but only 0.2uA)
  service.radio.rf95.sleep();

  nodeDB.saveToDisk();

#ifdef RESET_OLED
  digitalWrite(RESET_OLED, 1); // put the display in reset before killing its power
#endif

#ifdef VEXT_ENABLE
  digitalWrite(VEXT_ENABLE, 1); // turn off the display power
#endif

  setLed(false);

#ifdef T_BEAM_V10
  if (axp192_found)
  {
    // No need to turn this off if the power draw in sleep mode really is just 0.2uA and turning it off would
    // leave floating input for the IRQ line

    // If we want to leave the radio receving in would be 11.5mA current draw, but most of the time it is just waiting
    // in its sequencer (true?) so the average power draw should be much lower even if we were listinging for packets
    // all the time.

    // axp.setPowerOutPut(AXP192_LDO2, AXP202_OFF); // LORA radio

    setGPSPower(false);
  }
#endif

  /*
  Some ESP32 IOs have internal pullups or pulldowns, which are enabled by default. 
  If an external circuit drives this pin in deep sleep mode, current consumption may 
  increase due to current flowing through these pullups and pulldowns.

  To isolate a pin, preventing extra current draw, call rtc_gpio_isolate() function.
  For example, on ESP32-WROVER module, GPIO12 is pulled up externally. 
  GPIO12 also has an internal pulldown in the ESP32 chip. This means that in deep sleep, 
  some current will flow through these external and internal resistors, increasing deep 
  sleep current above the minimal possible value. 

  Note: we don't isolate pins that are used for the LORA, LED, i2c, spi or the wake button
  */
  static const uint8_t rtcGpios[] = {/* 0, */ 2,
  /* 4, */
#ifndef USE_JTAG
                                     12, 13, /* 14, */ /* 15, */
#endif
                                     /* 25, */ 26, /* 27, */
                                     32, 33, 34, 35, 36, 37, /* 38, */ 39};

  for (int i = 0; i < sizeof(rtcGpios); i++)
    rtc_gpio_isolate((gpio_num_t)rtcGpios[i]);

  // FIXME, disable internal rtc pullups/pulldowns on the non isolated pins. for inputs that we aren't using
  // to detect wake and in normal operation the external part drives them hard.

  // We want RTC peripherals to stay on
  esp_sleep_pd_config(ESP_PD_DOMAIN_RTC_PERIPH, ESP_PD_OPTION_ON);

#ifdef BUTTON_PIN
  // Only GPIOs which are have RTC functionality can be used in this bit map: 0,2,4,12-15,25-27,32-39.
  uint64_t gpioMask = (1ULL << BUTTON_PIN);

  // Not needed because both of the current boards have external pullups
  // FIXME change polarity in hw so we can wake on ANY_HIGH instead - that would allow us to use all three buttons (instead of just the first)
  // gpio_pullup_en((gpio_num_t)BUTTON_PIN);

  esp_sleep_enable_ext1_wakeup(gpioMask, ESP_EXT1_WAKEUP_ALL_LOW);
#endif

  esp_sleep_enable_timer_wakeup(msecToWake * 1000ULL); // call expects usecs
  esp_deep_sleep_start();                              // TBD mA sleep current (battery)
}

/**
 * enter light sleep (preserves ram but stops everything about CPU).
 * 
 * Returns (after restoring hw state) when the user presses a button or we get a LoRa interrupt
 */
esp_sleep_wakeup_cause_t doLightSleep(uint64_t sleepMsec) // FIXME, use a more reasonable default
{
  //DEBUG_MSG("Enter light sleep\n");
  uint64_t sleepUsec = sleepMsec * 1000LL;

  Serial.flush();            // send all our characters before we stop cpu clock
  setBluetoothEnable(false); // has to be off before calling light sleep

  // NOTE! ESP docs say we must disable bluetooth and wifi before light sleep

  // We want RTC peripherals to stay on
  esp_sleep_pd_config(ESP_PD_DOMAIN_RTC_PERIPH, ESP_PD_OPTION_ON);

  gpio_wakeup_enable((gpio_num_t)BUTTON_PIN, GPIO_INTR_LOW_LEVEL); // when user presses, this button goes low
  gpio_wakeup_enable((gpio_num_t)DIO0_GPIO, GPIO_INTR_HIGH_LEVEL); // RF95 interrupt, active high
#ifdef PMU_IRQ
  gpio_wakeup_enable((gpio_num_t)PMU_IRQ, GPIO_INTR_HIGH_LEVEL); // pmu irq
#endif
  assert(esp_sleep_enable_gpio_wakeup() == ESP_OK);
  assert(esp_sleep_enable_timer_wakeup(sleepUsec) == ESP_OK);
  assert(esp_light_sleep_start() == ESP_OK);
  //DEBUG_MSG("Exit light sleep\n");
  return esp_sleep_get_wakeup_cause();
}

#if 0
// not legal on the stock android ESP build

/**
 * enable modem sleep mode as needed and available.  Should lower our CPU current draw to an average of about 20mA.
 * 
 * per https://docs.espressif.com/projects/esp-idf/en/latest/api-reference/system/power_management.html
 * 
 * supposedly according to https://github.com/espressif/arduino-esp32/issues/475 this is already done in arduino
 */
void enableModemSleep()
{
  static esp_pm_config_esp32_t config; // filled with zeros because bss

  config.max_freq_mhz = CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ;
  config.min_freq_mhz = 10; // 10Mhz is minimum recommended
  config.light_sleep_enable = false;
  DEBUG_MSG("Sleep request result %x\n", esp_pm_configure(&config));
}
#endif