pin_manager.cpp

#include "pin_manager.h"
#include "wled.h"

#ifdef WLED_DEBUG
static void DebugPrintOwnerTag(PinOwner tag)
{
  uint32_t q = static_cast<uint8_t>(tag);
  if (q) {
    DEBUG_PRINTF("0x%02x (%d)", q, q);
  } else {
    DEBUG_PRINT(F("(no owner)"));
  }
}
#endif

/// Actual allocation/deallocation routines
bool PinManagerClass::deallocatePin(byte gpio, PinOwner tag)
{
  if (gpio == 0xFF) return true;           // explicitly allow clients to free -1 as a no-op
  if (!isPinOk(gpio, false)) return false; // but return false for any other invalid pin

  // if a non-zero ownerTag, only allow de-allocation if the owner's tag is provided
  if ((ownerTag[gpio] != PinOwner::None) && (ownerTag[gpio] != tag)) {
    #ifdef WLED_DEBUG
    DEBUG_PRINT(F("PIN DEALLOC: IO "));
    DEBUG_PRINT(gpio);
    DEBUG_PRINT(F(" allocated by "));
    DebugPrintOwnerTag(ownerTag[gpio]);
    DEBUG_PRINT(F(", but attempted de-allocation by "));
    DebugPrintOwnerTag(tag);
    #endif
    return false;
  }

  byte by = gpio >> 3;
  byte bi = gpio - 8*by;
  bitWrite(pinAlloc[by], bi, false);
  ownerTag[gpio] = PinOwner::None;
  return true;
}

// support function for deallocating multiple pins
bool PinManagerClass::deallocateMultiplePins(const uint8_t *pinArray, byte arrayElementCount, PinOwner tag)
{
  bool shouldFail = false;
  DEBUG_PRINTLN(F("MULTIPIN DEALLOC"));
  // first verify the pins are OK and allocated by selected owner
  for (int i = 0; i < arrayElementCount; i++) {
    byte gpio = pinArray[i];
    if (gpio == 0xFF) {
      // explicit support for io -1 as a no-op (no allocation of pin),
      // as this can greatly simplify configuration arrays
      continue;
    }
    if (isPinAllocated(gpio, tag)) {
      // if the current pin is allocated by selected owner it is possible to release it
      continue;
    }
    #ifdef WLED_DEBUG
    DEBUG_PRINT(F("PIN DEALLOC: IO "));
    DEBUG_PRINT(gpio);
    DEBUG_PRINT(F(" allocated by "));
    DebugPrintOwnerTag(ownerTag[gpio]);
    DEBUG_PRINT(F(", but attempted de-allocation by "));
    DebugPrintOwnerTag(tag);
    #endif
    shouldFail = true;
  }
  if (shouldFail) {
    return false; // no pins deallocated
  }
  if (tag==PinOwner::HW_I2C) {
    if (i2cAllocCount && --i2cAllocCount>0) {
      // no deallocation done until last owner releases pins
      return true;
    }
  }
  if (tag==PinOwner::HW_SPI) {
    if (spiAllocCount && --spiAllocCount>0) {
      // no deallocation done until last owner releases pins
      return true;
    }
  }
  for (int i = 0; i < arrayElementCount; i++) {
    deallocatePin(pinArray[i], tag);
  }
  return true;
}

bool PinManagerClass::deallocateMultiplePins(const managed_pin_type * mptArray, byte arrayElementCount, PinOwner tag)
{
  uint8_t pins[arrayElementCount];
  for (int i=0; i<arrayElementCount; i++) pins[i] = mptArray[i].pin;
  return deallocateMultiplePins(pins, arrayElementCount, tag);
}

bool PinManagerClass::allocateMultiplePins(const managed_pin_type * mptArray, byte arrayElementCount, PinOwner tag)
{
  bool shouldFail = false;
  // first verify the pins are OK and not already allocated
  for (int i = 0; i < arrayElementCount; i++) {
    byte gpio = mptArray[i].pin;
    if (gpio == 0xFF) {
      // explicit support for io -1 as a no-op (no allocation of pin),
      // as this can greatly simplify configuration arrays
      continue;
    }
    if (!isPinOk(gpio, mptArray[i].isOutput)) {
      #ifdef WLED_DEBUG
      DEBUG_PRINT(F("PIN ALLOC: Invalid pin attempted to be allocated: GPIO "));
      DEBUG_PRINT(gpio);
      DEBUG_PRINT(" as "); DEBUG_PRINT(mptArray[i].isOutput ? "output": "input");
      DEBUG_PRINTLN(F(""));
      #endif
      shouldFail = true;
    }
    if ((tag==PinOwner::HW_I2C || tag==PinOwner::HW_SPI) && isPinAllocated(gpio, tag)) {
      // allow multiple "allocations" of HW I2C & SPI bus pins
      continue;
    } else if (isPinAllocated(gpio)) {
      #ifdef WLED_DEBUG
      DEBUG_PRINT(F("PIN ALLOC: FAIL: IO "));
      DEBUG_PRINT(gpio);
      DEBUG_PRINT(F(" already allocated by "));
      DebugPrintOwnerTag(ownerTag[gpio]);
      DEBUG_PRINTLN(F(""));
      #endif
      shouldFail = true;
    }
  }
  if (shouldFail) {
    return false;
  }

  if (tag==PinOwner::HW_I2C) i2cAllocCount++;
  if (tag==PinOwner::HW_SPI) spiAllocCount++;

  // all pins are available .. track each one
  for (int i = 0; i < arrayElementCount; i++) {
    byte gpio = mptArray[i].pin;
    if (gpio == 0xFF) {
      // allow callers to include -1 value as non-requested pin
      // as this can greatly simplify configuration arrays
      continue;
    }
    if (gpio >= WLED_NUM_PINS)
      continue; // other unexpected GPIO => avoid array bounds violation

    byte by = gpio >> 3;
    byte bi = gpio - 8*by;
    bitWrite(pinAlloc[by], bi, true);
    ownerTag[gpio] = tag;
    #ifdef WLED_DEBUG
    DEBUG_PRINT(F("PIN ALLOC: Pin "));
    DEBUG_PRINT(gpio);
    DEBUG_PRINT(F(" allocated by "));
    DebugPrintOwnerTag(tag);
    DEBUG_PRINTLN(F(""));
    #endif
  }
  return true;
}

bool PinManagerClass::allocatePin(byte gpio, bool output, PinOwner tag)
{
  // HW I2C & SPI pins have to be allocated using allocateMultiplePins variant since there is always SCL/SDA pair
  if (!isPinOk(gpio, output) || (gpio >= WLED_NUM_PINS) || tag==PinOwner::HW_I2C || tag==PinOwner::HW_SPI) {
    #ifdef WLED_DEBUG
    if (gpio < 255) {  // 255 (-1) is the "not defined GPIO"
      if (!isPinOk(gpio, output)) {
        DEBUG_PRINT(F("PIN ALLOC: FAIL for owner "));
        DebugPrintOwnerTag(tag);
        DEBUG_PRINT(F(": GPIO ")); DEBUG_PRINT(gpio);
        if (output) DEBUG_PRINTLN(F(" cannot be used for i/o on this MCU."));
        else DEBUG_PRINTLN(F(" cannot be used as input on this MCU."));
      } else {
        DEBUG_PRINT(F("PIN ALLOC: FAIL: GPIO ")); DEBUG_PRINT(gpio);
        DEBUG_PRINTLN(F(" - HW I2C & SPI pins have to be allocated using allocateMultiplePins()"));
      }
    }
    #endif
    return false;
  }
  if (isPinAllocated(gpio)) {
    #ifdef WLED_DEBUG
    DEBUG_PRINT(F("PIN ALLOC: Pin "));
    DEBUG_PRINT(gpio);
    DEBUG_PRINT(F(" already allocated by "));
    DebugPrintOwnerTag(ownerTag[gpio]);
    DEBUG_PRINTLN(F(""));
    #endif
    return false;
  }

  byte by = gpio >> 3;
  byte bi = gpio - 8*by;
  bitWrite(pinAlloc[by], bi, true);
  ownerTag[gpio] = tag;
  #ifdef WLED_DEBUG
  DEBUG_PRINT(F("PIN ALLOC: Pin "));
  DEBUG_PRINT(gpio);
  DEBUG_PRINT(F(" successfully allocated by "));
  DebugPrintOwnerTag(tag);
  DEBUG_PRINTLN(F(""));
  #endif

  return true;
}

// if tag is set to PinOwner::None, checks for ANY owner of the pin.
// if tag is set to any other value, checks if that tag is the current owner of the pin.
bool PinManagerClass::isPinAllocated(byte gpio, PinOwner tag)
{
  if (!isPinOk(gpio, false)) return true;
  if ((tag != PinOwner::None) && (ownerTag[gpio] != tag)) return false;
  if (gpio >= WLED_NUM_PINS) return false; // catch error case, to avoid array out-of-bounds access
  byte by = gpio >> 3;
  byte bi = gpio - (by<<3);
  return bitRead(pinAlloc[by], bi);
}

/* see https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/api-reference/peripherals/gpio.html
 * The ESP32-S3 chip features 45 physical GPIO pins (GPIO0 ~ GPIO21 and GPIO26 ~ GPIO48). Each pin can be used as a general-purpose I/O
 * Strapping pins: GPIO0, GPIO3, GPIO45 and GPIO46 are strapping pins. For more infomation, please refer to ESP32-S3 datasheet.
 * Serial TX = GPIO43, RX = GPIO44; LED BUILTIN is usually GPIO39
 * USB-JTAG: GPIO 19 and 20 are used by USB-JTAG by default. In order to use them as GPIOs, USB-JTAG will be disabled by the drivers.
 * SPI0/1: GPIO26-32 are usually used for SPI flash and PSRAM and not recommended for other uses.
 * When using Octal Flash or Octal PSRAM or both, GPIO33~37 are connected to SPIIO4 ~ SPIIO7 and SPIDQS. Therefore, on boards embedded with ESP32-S3R8 / ESP32-S3R8V chip, GPIO33~37 are also not recommended for other uses.
 *
 * see https://docs.espressif.com/projects/esp-idf/en/v4.4.2/esp32s3/api-reference/peripherals/adc.html
 *     https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/api-reference/peripherals/adc_oneshot.html
 * ADC1: GPIO1  - GPIO10 (channel 0..9)
 * ADC2: GPIO11 - GPIO20 (channel 0..9)
 * adc_power_acquire(): Please do not use the interrupt of GPIO36 and GPIO39 when using ADC or Wi-Fi and Bluetooth with sleep mode enabled. As a workaround, call adc_power_acquire() in the APP.
 * Since the ADC2 module is also used by the Wi-Fi, reading operation of adc2_get_raw() may fail between esp_wifi_start() and esp_wifi_stop(). Use the return code to see whether the reading is successful.
 */

// Check if supplied GPIO is ok to use
bool PinManagerClass::isPinOk(byte gpio, bool output)
{
#ifdef ESP32
  if (digitalPinIsValid(gpio)) {
  #if defined(CONFIG_IDF_TARGET_ESP32C3)
    // strapping pins: 2, 8, & 9
    if (gpio > 11 && gpio < 18) return false;     // 11-17 SPI FLASH
    if (gpio > 17 && gpio < 20) return false;     // 18-19 USB-JTAG
  #elif defined(CONFIG_IDF_TARGET_ESP32S3)
    // 00 to 18 are for general use. Be careful about straping pins GPIO0 and GPIO3 - these may be pulled-up or pulled-down on your board.
    if (gpio > 18 && gpio < 21) return false;     // 19 + 20 = USB-JTAG. Not recommended for other uses.
    if (gpio > 21 && gpio < 33) return false;     // 22 to 32: not connected + SPI FLASH
    //if (gpio > 32 && gpio < 38) return false;     // 33 to 37: not available if using _octal_ SPI Flash or _octal_ PSRAM
    // 38 to 48 are for general use. Be careful about straping pins GPIO45 and GPIO46 - these may be pull-up or pulled-down on your board.
  #elif defined(CONFIG_IDF_TARGET_ESP32S2)
    // strapping pins: 0, 45 & 46
    if (gpio > 21 && gpio < 33) return false;     // 22 to 32: not connected + SPI FLASH
    // JTAG: GPIO39-42 are usually used for inline debugging
    // GPIO46 is input only and pulled down
  #else
    if (gpio > 5 && gpio < 12) return false;      //SPI flash pins
  #endif
    if (output) return digitalPinCanOutput(gpio);
    else        return true;
  }
#else
  if (gpio <  6) return true;
  if (gpio < 12) return false; //SPI flash pins
  if (gpio < 17) return true;
#endif
  return false;
}

PinOwner PinManagerClass::getPinOwner(byte gpio) {
  if (gpio >= WLED_NUM_PINS) return PinOwner::None; // catch error case, to avoid array out-of-bounds access
  if (!isPinOk(gpio, false)) return PinOwner::None;
  return ownerTag[gpio];
}

#ifdef ARDUINO_ARCH_ESP32
#if defined(CONFIG_IDF_TARGET_ESP32C3)
  #define MAX_LED_CHANNELS 6
#else
  #if defined(CONFIG_IDF_TARGET_ESP32S2) || defined(CONFIG_IDF_TARGET_ESP32S3)
    #define MAX_LED_CHANNELS 8
  #else
    #define MAX_LED_CHANNELS 16
  #endif
#endif
byte PinManagerClass::allocateLedc(byte channels)
{
  if (channels > MAX_LED_CHANNELS || channels == 0) return 255;
  byte ca = 0;
  for (byte i = 0; i < MAX_LED_CHANNELS; i++) {
    byte by = i >> 3;
    byte bi = i - 8*by;
    if (bitRead(ledcAlloc[by], bi)) { //found occupied pin
      ca = 0;
    } else {
      ca++;
    }
    if (ca >= channels) { //enough free channels
      byte in = (i + 1) - ca;
      for (byte j = 0; j < ca; j++) {
        byte bChan = in + j;
        byte byChan = bChan >> 3;
        byte biChan = bChan - 8*byChan;
        bitWrite(ledcAlloc[byChan], biChan, true);
      }
      return in;
    }
  }
  return 255; //not enough consecutive free LEDC channels
}

void PinManagerClass::deallocateLedc(byte pos, byte channels)
{
  for (byte j = pos; j < pos + channels; j++) {
    if (j > MAX_LED_CHANNELS) return;
    byte by = j >> 3;
    byte bi = j - 8*by;
    bitWrite(ledcAlloc[by], bi, false);
  }
}
#endif

PinManagerClass pinManager = PinManagerClass();