spi.cpp

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#include "spi.h"
#include "esphome/core/log.h"
#include "esphome/core/helpers.h"
#include "esphome/core/application.h"

namespace esphome {
namespace spi {

static const char *const TAG = "spi";

void IRAM_ATTR HOT SPIComponent::disable() {
#ifdef USE_SPI_ARDUINO_BACKEND
  if (this->hw_spi_ != nullptr) {
    this->hw_spi_->endTransaction();
  }
#endif  // USE_SPI_ARDUINO_BACKEND
  if (this->active_cs_) {
    this->active_cs_->digital_write(true);
    this->active_cs_ = nullptr;
  }
}
void SPIComponent::setup() {
  ESP_LOGCONFIG(TAG, "Setting up SPI bus...");
  this->clk_->setup();
  this->clk_->digital_write(true);

#ifdef USE_SPI_ARDUINO_BACKEND
  bool use_hw_spi = !this->force_sw_;
  const bool has_miso = this->miso_ != nullptr;
  const bool has_mosi = this->mosi_ != nullptr;
  int8_t clk_pin = -1, miso_pin = -1, mosi_pin = -1;

  if (!this->clk_->is_internal())
    use_hw_spi = false;
  if (has_miso && !miso_->is_internal())
    use_hw_spi = false;
  if (has_mosi && !mosi_->is_internal())
    use_hw_spi = false;
  if (use_hw_spi) {
    auto *clk_internal = (InternalGPIOPin *) clk_;
    auto *miso_internal = (InternalGPIOPin *) miso_;
    auto *mosi_internal = (InternalGPIOPin *) mosi_;

    if (clk_internal->is_inverted())
      use_hw_spi = false;
    if (has_miso && miso_internal->is_inverted())
      use_hw_spi = false;
    if (has_mosi && mosi_internal->is_inverted())
      use_hw_spi = false;

    if (use_hw_spi) {
      clk_pin = clk_internal->get_pin();
      miso_pin = has_miso ? miso_internal->get_pin() : -1;
      mosi_pin = has_mosi ? mosi_internal->get_pin() : -1;
    }
  }
#ifdef USE_ESP8266
  if (!(clk_pin == 6 && miso_pin == 7 && mosi_pin == 8) &&
      !(clk_pin == 14 && (!has_miso || miso_pin == 12) && (!has_mosi || mosi_pin == 13)))
    use_hw_spi = false;

  if (use_hw_spi) {
    this->hw_spi_ = &SPI;
    this->hw_spi_->pins(clk_pin, miso_pin, mosi_pin, 0);
    this->hw_spi_->begin();
    return;
  }
#endif  // USE_ESP8266
#ifdef USE_ESP32
  static uint8_t spi_bus_num = 0;
  if (spi_bus_num >= 2) {
    use_hw_spi = false;
  }

  if (use_hw_spi) {
    if (spi_bus_num == 0) {
      this->hw_spi_ = &SPI;
    } else {
#if defined(USE_ESP32_VARIANT_ESP32C3) || defined(USE_ESP32_VARIANT_ESP32S2) || defined(USE_ESP32_VARIANT_ESP32S3)
      this->hw_spi_ = new SPIClass(FSPI);  // NOLINT(cppcoreguidelines-owning-memory)
#else
      this->hw_spi_ = new SPIClass(HSPI);  // NOLINT(cppcoreguidelines-owning-memory)
#endif  // USE_ESP32_VARIANT
    }
    spi_bus_num++;
    this->hw_spi_->begin(clk_pin, miso_pin, mosi_pin);
    return;
  }
#endif  // USE_ESP32
#endif  // USE_SPI_ARDUINO_BACKEND

  if (this->miso_ != nullptr) {
    this->miso_->setup();
  }
  if (this->mosi_ != nullptr) {
    this->mosi_->setup();
    this->mosi_->digital_write(false);
  }
}
void SPIComponent::dump_config() {
  ESP_LOGCONFIG(TAG, "SPI bus:");
  LOG_PIN("  CLK Pin: ", this->clk_);
  LOG_PIN("  MISO Pin: ", this->miso_);
  LOG_PIN("  MOSI Pin: ", this->mosi_);
#ifdef USE_SPI_ARDUINO_BACKEND
  ESP_LOGCONFIG(TAG, "  Using HW SPI: %s", YESNO(this->hw_spi_ != nullptr));
#endif  // USE_SPI_ARDUINO_BACKEND
}
float SPIComponent::get_setup_priority() const { return setup_priority::BUS; }

void SPIComponent::cycle_clock_(bool value) {
  uint32_t start = arch_get_cpu_cycle_count();
  while (start - arch_get_cpu_cycle_count() < this->wait_cycle_)
    ;
  this->clk_->digital_write(value);
  start += this->wait_cycle_;
  while (start - arch_get_cpu_cycle_count() < this->wait_cycle_)
    ;
}

// NOLINTNEXTLINE
#ifndef CLANG_TIDY
#pragma GCC optimize("unroll-loops")
// NOLINTNEXTLINE
#pragma GCC optimize("O2")
#endif  // CLANG_TIDY

template<SPIBitOrder BIT_ORDER, SPIClockPolarity CLOCK_POLARITY, SPIClockPhase CLOCK_PHASE, bool READ, bool WRITE>
uint8_t HOT SPIComponent::transfer_(uint8_t data) {
  // Clock starts out at idle level
  this->clk_->digital_write(CLOCK_POLARITY);
  uint8_t out_data = 0;

  for (uint8_t i = 0; i < 8; i++) {
    uint8_t shift;
    if (BIT_ORDER == BIT_ORDER_MSB_FIRST) {
      shift = 7 - i;
    } else {
      shift = i;
    }

    if (CLOCK_PHASE == CLOCK_PHASE_LEADING) {
      // sampling on leading edge
      if (WRITE) {
        this->mosi_->digital_write(data & (1 << shift));
      }

      // SAMPLE!
      this->cycle_clock_(!CLOCK_POLARITY);

      if (READ) {
        out_data |= uint8_t(this->miso_->digital_read()) << shift;
      }

      this->cycle_clock_(CLOCK_POLARITY);
    } else {
      // sampling on trailing edge
      this->cycle_clock_(!CLOCK_POLARITY);

      if (WRITE) {
        this->mosi_->digital_write(data & (1 << shift));
      }

      // SAMPLE!
      this->cycle_clock_(CLOCK_POLARITY);

      if (READ) {
        out_data |= uint8_t(this->miso_->digital_read()) << shift;
      }
    }
  }

  App.feed_wdt();

  return out_data;
}

// Generate with (py3):
//
// from itertools import product
// bit_orders = ['BIT_ORDER_LSB_FIRST', 'BIT_ORDER_MSB_FIRST']
// clock_pols = ['CLOCK_POLARITY_LOW', 'CLOCK_POLARITY_HIGH']
// clock_phases = ['CLOCK_PHASE_LEADING', 'CLOCK_PHASE_TRAILING']
// reads = [False, True]
// writes = [False, True]
// cpp_bool = {False: 'false', True: 'true'}
// for b, cpol, cph, r, w in product(bit_orders, clock_pols, clock_phases, reads, writes):
//     if not r and not w:
//         continue
//     print(f"template uint8_t SPIComponent::transfer_<{b}, {cpol}, {cph}, {cpp_bool[r]}, {cpp_bool[w]}>(uint8_t
//     data);")

template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_LEADING, false, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_LEADING, true, false>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_LEADING, true, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_TRAILING, false, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_TRAILING, true, false>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_TRAILING, true, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_LEADING, false, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_LEADING, true, false>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_LEADING, true, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_TRAILING, false, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_TRAILING, true, false>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_LSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_TRAILING, true, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_LEADING, false, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_LEADING, true, false>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_LEADING, true, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_TRAILING, false, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_TRAILING, true, false>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_LOW, CLOCK_PHASE_TRAILING, true, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_LEADING, false, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_LEADING, true, false>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_LEADING, true, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_TRAILING, false, true>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_TRAILING, true, false>(
    uint8_t data);
template uint8_t SPIComponent::transfer_<BIT_ORDER_MSB_FIRST, CLOCK_POLARITY_HIGH, CLOCK_PHASE_TRAILING, true, true>(
    uint8_t data);

}  // namespace spi
}  // namespace esphome