unit_bmm350.hpp

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/*
 * SPDX-FileCopyrightText: 2026 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_IMU_UNIT_UNIT_BMM350_HPP
#define M5_UNIT_IMU_UNIT_UNIT_BMM350_HPP
 
#include <M5UnitComponent.hpp>
#include <m5_utility/container/circular_buffer.hpp>
#include <memory>
#include "unit_bmm350_data.hpp"
#include "../imu/imu_data_source.hpp"
 
namespace m5 {
namespace unit {
 
class UnitBMM350 : public Component,
                   public PeriodicMeasurementAdapter<UnitBMM350, bmm350::Data>,
                   public m5::imu::IMUDataSource {
    M5_UNIT_COMPONENT_HPP_BUILDER(UnitBMM350, 0x14);
 
public:
    struct config_t {
        bool start_periodic{true};
        bmm350::DataRate rate{bmm350::DataRate::Rate100Hz};
        bmm350::Averaging avg{bmm350::Averaging::X4};
    };
 
    explicit UnitBMM350(const uint8_t addr = DEFAULT_ADDRESS);
    virtual ~UnitBMM350()
    {
    }
 
    virtual bool begin() override;
    virtual void update(const bool force = false) override;
 
    config_t config() const
    {
        return _cfg;
    }
    void config(const config_t& cfg)
    {
        _cfg = cfg;
    }
 
    bool writeDataRate(const bmm350::DataRate rate);
    bool writeAveraging(const bmm350::Averaging avg);
    bool readDataRate(bmm350::DataRate& rate);
    bool readAveraging(bmm350::Averaging& avg);
 
    bool softReset();
 
 
    bool startPeriodicMeasurement(const bmm350::DataRate rate, const bmm350::Averaging avg);
    bool startPeriodicMeasurement();
    bool stopPeriodicMeasurement();
 
 
    bool sleep() override;
    bool wakeup() override;
 
    virtual m5::imu::Capability imuSpec() const override
    {
        return m5::imu::Capability::Mag | m5::imu::Capability::Temp;
    }
    virtual m5::imu::Capability readImuRaw(m5::imu::imu_raw_data_t& out) override;
    virtual void imuConvertParam(m5::imu::imu_convert_param_t& out) const override;
 
protected:
    bool start_periodic_measurement(const bmm350::DataRate rate, const bmm350::Averaging avg);
    bool start_periodic_measurement();
    bool stop_periodic_measurement();
    bool read_measurement(bmm350::Data& d);
    bool write_register8_verified(const uint8_t reg, const uint8_t val);
    // BMM350 I2C reads are always prefixed with 2 dummy bytes; every register read
    // (including REG_CHIP_ID) must go through this wrapper.
    bool read_registers(const uint8_t reg, uint8_t* out, const uint32_t len);
    bool read_register8(const uint8_t reg, uint8_t& out);
    bool download_otp(bmm350::otp_compensation_t& comp);
    // AGGR_SET->UPD_OAE->SUS->Normal tail shared by begin() and the writeDataRate()/
    // writeAveraging() setters (Bosch bmm350_set_odr_performance() + bmm350_set_powermode():
    // the SUS step is always issued here since REG_PMU_CMD was just left at UPD_OAE). Verifies
    // REG_PMU_CMD_STATUS_0.pwr_mode_is_normal after the Normal transition.
    bool commit_odr_avg(const bmm350::DataRate rate, const bmm350::Averaging avg);
 
    M5_UNIT_COMPONENT_PERIODIC_MEASUREMENT_ADAPTER_HPP_BUILDER(UnitBMM350, bmm350::Data);
 
private:
    config_t _cfg{};
    bmm350::otp_compensation_t _comp{};
    uint32_t _pushed{}, _consumed{};  // readImuRaw pop counters (do not disturb latest()/oldest())
    std::unique_ptr<m5::container::CircularBuffer<bmm350::Data>> _data{};
};
 
namespace bmm350 {
constexpr uint32_t DEFAULT_STORED_SIZE{8};
 
namespace command {
// Register addresses (I2C addr 0x14 (ADSEL=LOW) / 0x15 (ADSEL=HIGH))
constexpr uint8_t REG_CHIP_ID{0x00};
constexpr uint8_t REG_PMU_CMD_AGGR_SET{0x04};  // bits[3:0]=odr, bits[5:4]=avg
constexpr uint8_t REG_PMU_CMD{0x06};
constexpr uint8_t REG_PMU_CMD_STATUS_0{0x07};  // bit3=pwr_mode_is_normal, bit4=cmd_is_illegal
constexpr uint8_t REG_INT_CTRL{0x2E};          // bit7 = drdy_data_reg_en
constexpr uint8_t REG_INT_STATUS{0x30};        // bit2 = drdy_data_reg (clears on read)
constexpr uint8_t REG_MAG_X_XLSB{0x31};        // 12 bytes: mag X/Y/Z (24bit each) + temperature (24bit)
constexpr uint8_t REG_OTP_CMD{0x50};
constexpr uint8_t REG_OTP_DATA_MSB{0x52};
constexpr uint8_t REG_OTP_DATA_LSB{0x53};
constexpr uint8_t REG_OTP_STATUS{0x55};
constexpr uint8_t REG_CMD{0x7E};
}  // namespace command
}  // namespace bmm350
 
}  // namespace unit
}  // namespace m5
#endif