drv_hrt.h

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#pragma once

#include <sys/ioctl.h>
#include <sys/types.h>
#include <stdbool.h>
#include <inttypes.h>

#include <px4_time.h>
#include <queue.h>

__BEGIN_DECLS

typedef uint64_t    hrt_abstime;

typedef void    (* hrt_callout)(void *arg);

typedef struct hrt_call {
    struct sq_entry_s   link;

    hrt_abstime     deadline;
    hrt_abstime     period;
    hrt_callout     callout;
    void            *arg;
} *hrt_call_t;

__EXPORT extern hrt_abstime hrt_absolute_time(void);

__EXPORT extern hrt_abstime ts_to_abstime(const struct timespec *ts);

__EXPORT extern void    abstime_to_ts(struct timespec *ts, hrt_abstime abstime);

static inline hrt_abstime hrt_elapsed_time(const hrt_abstime *then)
{
    return hrt_absolute_time() - *then;
}

__EXPORT extern hrt_abstime hrt_elapsed_time_atomic(const volatile hrt_abstime *then);

__EXPORT extern hrt_abstime hrt_store_absolute_time(volatile hrt_abstime *now);

#ifdef __PX4_QURT

__EXPORT extern int hrt_set_absolute_time_offset(int32_t time_diff_us);
#endif

__EXPORT extern void    hrt_call_after(struct hrt_call *entry, hrt_abstime delay, hrt_callout callout, void *arg);

__EXPORT extern void    hrt_call_at(struct hrt_call *entry, hrt_abstime calltime, hrt_callout callout, void *arg);

__EXPORT extern void    hrt_call_every(struct hrt_call *entry, hrt_abstime delay, hrt_abstime interval,
                       hrt_callout callout, void *arg);

__EXPORT extern bool    hrt_called(struct hrt_call *entry);

__EXPORT extern void    hrt_cancel(struct hrt_call *entry);

__EXPORT extern void    hrt_call_init(struct hrt_call *entry);

/*
 * delay a hrt_call_every() periodic call by the given number of
 * microseconds. This should be called from within the callout to
 * cause the callout to be re-scheduled for a later time. The periodic
 * callouts will then continue from that new base time at the
 * previously specified period.
 */
__EXPORT extern void    hrt_call_delay(struct hrt_call *entry, hrt_abstime delay);

/*
 * Initialise the HRT.
 */
__EXPORT extern void    hrt_init(void);

#ifdef __PX4_POSIX

__EXPORT extern hrt_abstime hrt_reset(void);

__EXPORT extern hrt_abstime hrt_absolute_time_offset(void);

#endif

__END_DECLS



#ifdef  __cplusplus

namespace time_literals
{

// User-defined integer literals for different time units.
// The base unit is hrt_abstime in microseconds

constexpr hrt_abstime operator "" _s(unsigned long long seconds)
{
    return hrt_abstime(seconds * 1000000ULL);
}

constexpr hrt_abstime operator "" _ms(unsigned long long seconds)
{
    return hrt_abstime(seconds * 1000ULL);
}

constexpr hrt_abstime operator "" _us(unsigned long long seconds)
{
    return hrt_abstime(seconds);
}

} /* namespace time_literals */


#endif /* __cplusplus */