i2c_bus_clear.h

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#ifndef NEXUS_I2C_BUS_CLEAR_H
#define NEXUS_I2C_BUS_CLEAR_H
 
#include "nexus/core/time.h"
#ifdef __cplusplus
extern "C" {
#endif

#define NX_I2C_BUS_CLEAR_MAX_PULSES 9U

typedef struct {
    nx_result_t (*acquire)(void* context);
    nx_result_t (*drive)(void* context, bool scl_low, bool sda_low);
    nx_result_t (*sample)(void* context, bool* scl_high, bool* sda_high);
    nx_result_t (*wait_until)(void* context, nx_time_us_t target);
    nx_result_t (*release)(void* context);
} nx_i2c_bus_clear_ops_t;

typedef struct {
    const nx_i2c_bus_clear_ops_t* ops;
    void* context;
} nx_i2c_bus_clear_port_t;

typedef struct {
    uint32_t low_us;
    uint32_t high_us;
    uint32_t stop_setup_us;
    uint32_t stretch_poll_us;
} nx_i2c_bus_clear_timing_t;

typedef struct {
    nx_result_t primary;
    nx_result_t cleanup;
    uint8_t pulses;
    bool stop_observed;
    bool lease_held;
} nx_i2c_bus_clear_result_t;

typedef struct {
    nx_i2c_bus_clear_port_t port;
    nx_clock_t clock;
    nx_i2c_bus_clear_timing_t timing;
    nx_i2c_bus_clear_result_t result;
    nx_time_us_t last_time;
    bool clock_observed;
    bool initialized;
} nx_i2c_bus_clear_t;

nx_result_t nx_i2c_bus_clear_init(nx_i2c_bus_clear_t* clear,
                                  nx_i2c_bus_clear_port_t port,
                                  nx_clock_t clock,
                                  nx_i2c_bus_clear_timing_t timing);

nx_result_t nx_i2c_bus_clear_run(nx_i2c_bus_clear_t* clear,
                                 nx_time_us_t deadline,
                                 nx_time_us_t cleanup_deadline,
                                 nx_i2c_bus_clear_result_t* result);

nx_result_t nx_i2c_bus_clear_finish(nx_i2c_bus_clear_t* clear,
                                    nx_time_us_t deadline,
                                    nx_i2c_bus_clear_result_t* result);
 
#ifdef __cplusplus
}
#endif
#endif