lps22.cpp

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#include "lps22.h"
 
namespace esphome {
namespace lps22 {
 
static constexpr const char *const TAG = "lps22";
 
static constexpr uint8_t WHO_AM_I = 0x0F;
static constexpr uint8_t LPS22HB_ID = 0xB1;
static constexpr uint8_t LPS22HH_ID = 0xB3;
static constexpr uint8_t CTRL_REG2 = 0x11;
static constexpr uint8_t CTRL_REG2_ONE_SHOT_MASK = 0b1;
static constexpr uint8_t STATUS = 0x27;
static constexpr uint8_t STATUS_T_DA_MASK = 0b10;
static constexpr uint8_t STATUS_P_DA_MASK = 0b01;
static constexpr uint8_t TEMP_L = 0x2b;
static constexpr uint8_t PRES_OUT_XL = 0x28;
static constexpr uint8_t REF_P_XL = 0x28;
static constexpr uint8_t READ_ATTEMPTS = 10;
static constexpr uint8_t READ_INTERVAL = 5;
static constexpr float PRESSURE_SCALE = 1.0f / 4096.0f;
static constexpr float TEMPERATURE_SCALE = 0.01f;
 
void LPS22Component::setup() {
  uint8_t value = 0x00;
  this->read_register(WHO_AM_I, &value, 1);
  if (value != LPS22HB_ID && value != LPS22HH_ID) {
    ESP_LOGW(TAG, "device IDs as %02x, which isn't a known LPS22HB or LPS22HH ID", value);
    this->mark_failed();
  }
}
 
void LPS22Component::dump_config() {
  ESP_LOGCONFIG(TAG, "LPS22:");
  LOG_SENSOR("  ", "Temperature", this->temperature_sensor_);
  LOG_SENSOR("  ", "Pressure", this->pressure_sensor_);
  LOG_I2C_DEVICE(this);
  LOG_UPDATE_INTERVAL(this);
}
 
static constexpr uint32_t INTERVAL_READ = 0;
 
void LPS22Component::update() {
  uint8_t value = 0x00;
  this->read_register(CTRL_REG2, &value, 1);
  value |= CTRL_REG2_ONE_SHOT_MASK;
  this->write_register(CTRL_REG2, &value, 1);
  this->read_attempts_remaining_ = READ_ATTEMPTS;
  this->set_interval(INTERVAL_READ, READ_INTERVAL, [this]() { this->try_read_(); });
}
 
void LPS22Component::try_read_() {
  uint8_t value = 0x00;
  this->read_register(STATUS, &value, 1);
  const uint8_t expected_status_mask = STATUS_T_DA_MASK | STATUS_P_DA_MASK;
  if ((value & expected_status_mask) != expected_status_mask) {
    ESP_LOGD(TAG, "STATUS not ready: %x", value);
    if (--this->read_attempts_remaining_ == 0) {
      this->cancel_interval(INTERVAL_READ);
    }
    return;
  }
  this->cancel_interval(INTERVAL_READ);
 
  if (this->temperature_sensor_ != nullptr) {
    uint8_t t_buf[2]{0};
    this->read_register(TEMP_L, t_buf, 2);
    int16_t encoded = static_cast<int16_t>(encode_uint16(t_buf[1], t_buf[0]));
    float temp = TEMPERATURE_SCALE * static_cast<float>(encoded);
    this->temperature_sensor_->publish_state(temp);
  }
  if (this->pressure_sensor_ != nullptr) {
    uint8_t p_buf[3]{0};
    this->read_register(PRES_OUT_XL, p_buf, 3);
    uint32_t p_lsb = encode_uint24(p_buf[2], p_buf[1], p_buf[0]);
    this->pressure_sensor_->publish_state(PRESSURE_SCALE * static_cast<float>(p_lsb));
  }
}
 
}  // namespace lps22
}  // namespace esphome