Capture.h

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/*
 * Copyright (c) 2016-2017, Texas Instruments Incorporated
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/*!*****************************************************************************
 *  @file       Capture.h
 *  @brief      Capture driver interface
 *
 *  The capture header file should be included in an application as follows:
 *  @code
 *  #include <ti/drivers/Capture.h>
 *  @endcode
 *
 *  # Overview #
 *  The capture driver serves as the main interface for a typical RTOS
 *  application. Its purpose is to redirect the capture APIs to device specific
 *  implementations which are specified using a pointer to a #Capture_FxnTable.
 *  The device specific implementations are responsible for creating all the
 *  RTOS specific primitives to allow for thead-safe operation. The capture
 *  driver utilizes the general purpose timer hardware.
 *
 *  The capture driver internally handles the general purpose timer resource
 *  allocation. For each capture driver instance, Capture_open() occupies the
 *  specified timer, and Capture_close() releases the occupied timer resource.
 *
 *  # Usage#
 *  The capture driver is used to detect and time edge triggered events on a
 *  GPIO pin. The following example code opens a capture instance in falling
 *  edge mode. The interval returned in the callback function is in
 *  microseconds.
 *
 *  @code
 *  Capture_Handle    handle;
 *  Capture_Params    params;
 *
 *  Capture_Params_init(&params);
 *  params.mode  = Capture_FALLING_EDGE;
 *  params.callbackFxn = someCaptureCallbackFunction;
 *  params.periodUnit = Capture_PERIOD_US;
 *
 *  handle = Capture_open(someCapture_configIndexValue, &params);
 *
 *  if (handle == NULL) {
 *      //Capture_open() failed
 *      while(1);
 *  }
 *
 *  status = Capture_start(handle);
 *
 *  if (status == Capture_STATUS_ERROR) {
 *      //Capture_start() failed
 *      while(1);
 *  }
 *
 *  sleep(10000);
 *
 *  Capture_stop(handle);
 *  @endcode

 *  ### Capture Driver Configuration #
 *
 *  In order to use the capture APIs, the application is required to provide
 *  device specific capture configuration in the Board.c file. The capture
 *  driver interface defines a configuration data structure:
 *
 *  @code
 *  typedef struct Capture_Config_ {
 *      Capture_FxnTable const *fxnTablePtr;
 *      void                   *object;
 *      void             const *hwAttrs;
 *  } Capture_Config;
 *  @endcode
 *
 *  The application must declare an array of Capture_Config elements, named
 *  Capture_config[]. Each element of Capture_config[] is populated with
 *  pointers to a device specific capture driver implementation's function
 *  table, driver object, and hardware attributes. The hardware attributes
 *  define properties such as the timer peripheral's base address, interrupt
 *  number and interrupt priority. Each element in Capture_config[] corresponds
 *  to a capture instance, and none of the elements should have NULL pointers.
 *  There is no correlation between the index and the peripheral designation.
 *
 *  You will need to check the device specific capture driver implementation's
 *  header file for example configuration.
 *
 *  ### Initializing the Capture Driver #
 *
 *  Capture_init() must be called before any other capture APIs. This function
 *  calls the device implementation's capture initialization function, for each
 *  element of Capture_config[].
 *
 *  ### Modes of Operation #
 *
 *  The capture driver supports four modes of operation which may be specified
 *  in the Capture_Params.
 *
 *  #Capture_RISING_EDGE will capture rising edge triggers. After
 *  Capture_start() is called, the callback function specified in
 *  Capture_Params will be called after each rising edge is detected on the
 *  GPIO pin. This behavior will continue until Capture_stop() is called.
 *
 *  #Capture_FALLING_EDGE will capture falling edge triggers. After
 *  Capture_start() is called, the callback function specified in
 *  Capture_Params will be called after each falling edge is detected on the
 *  GPIO pin. This behavior will continue until Capture_stop() is called.
 *
 *  #Capture_ANY_EDGE will capture both rising and falling edge triggers. After
 *  Capture_start() is called, the callback function specified in
 *  Capture_Params will be called after each rising or falling edge is detected
 *  on the GPIO pin. This behavior will continue until Capture_stop() is
 *  called.
 *
 *  # Implementation #
 *
 *  The capture driver interface module is joined (at link time) to an
 *  array of Capture_Config data structures named *Capture_config*.
 *  Capture_config is implemented in the application with each entry being an
 *  instance of a capture peripheral. Each entry in *Capture_config* contains a:
 *  - (Capture_FxnTable *) to a set of functions that implement a capture
 *     peripheral
 *  - (void *) data object that is associated with the Capture_FxnTable
 *  - (void *) hardware attributes that are associated with the Capture_FxnTable
 *
 *  The capture APIs are redirected to the device specific implementations
 *  using the Capture_FxnTable pointer of the Capture_config entry.
 *  In order to use device specific functions of the capture driver directly,
 *  link in the correct driver library for your device and include the
 *  device specific capture driver header file (which in turn includes
 *  Capture.h). For example, for the MSP432 family of devices, you would
 *  include the following header file:
 *
 *  @code
 *  #include <ti/drivers/capture/CaptureMSP432.h>
 *  @endcode
 *
 *******************************************************************************
 */

#ifndef ti_drivers_Capture__include
#define ti_drivers_Capture__include

#ifdef __cplusplus
extern "C"
{
#endif

#include <stdint.h>

#define Capture_CMD_RESERVED             (32)

#define Capture_STATUS_RESERVED         (-32)

#define Capture_STATUS_SUCCESS          (0)

#define Capture_STATUS_ERROR            (-1)

#define Capture_STATUS_UNDEFINEDCMD    (-2)

typedef struct Capture_Config_ *Capture_Handle;


typedef enum Capture_Mode_ {
    Capture_RISING_EDGE,     
    Capture_FALLING_EDGE,    
    Capture_ANY_EDGE         
} Capture_Mode;

typedef enum Capture_PeriodUnits_ {
    Capture_PERIOD_US,       
    Capture_PERIOD_HZ,       
    Capture_PERIOD_COUNTS    
} Capture_PeriodUnits;


typedef void (*Capture_CallBackFxn)(Capture_Handle handle, uint32_t interval);

typedef struct Capture_Params_ {
    Capture_Mode           mode;

    Capture_CallBackFxn    callbackFxn;

    Capture_PeriodUnits    periodUnit;
} Capture_Params;

typedef void (*Capture_CloseFxn)(Capture_Handle handle);

typedef int_fast16_t (*Capture_ControlFxn)(Capture_Handle handle,
    uint_fast16_t cmd, void *arg);

typedef void (*Capture_InitFxn)(Capture_Handle handle);

typedef Capture_Handle (*Capture_OpenFxn)(Capture_Handle handle,
    Capture_Params *params);

typedef int32_t (*Capture_StartFxn)(Capture_Handle handle);

typedef void (*Capture_StopFxn)(Capture_Handle handle);

typedef struct Capture_FxnTable_ {
    Capture_CloseFxn closeFxn;

    Capture_ControlFxn controlFxn;

    Capture_InitFxn initFxn;

    Capture_OpenFxn openFxn;

    Capture_StartFxn startFxn;

    Capture_StopFxn stopFxn;
} Capture_FxnTable;

typedef struct Capture_Config_ {
    Capture_FxnTable const *fxnTablePtr;

    void                   *object;

    void             const *hwAttrs;
} Capture_Config;

extern void Capture_close(Capture_Handle handle);

extern int_fast16_t Capture_control(Capture_Handle handle, uint_fast16_t cmd,
    void *arg);

extern void Capture_init(void);

extern Capture_Handle Capture_open(uint_least8_t index, Capture_Params *params);

extern void Capture_Params_init(Capture_Params *params);

extern int32_t Capture_start(Capture_Handle handle);

extern void Capture_stop(Capture_Handle handle);

/* The following are included for backwards compatibility. These should not be
 * used by the application.
 */
#define CAPTURE_CMD_RESERVED           Capture_CMD_RESERVED
#define CAPTURE_STATUS_RESERVED        Capture_STATUS_RESERVED
#define CAPTURE_STATUS_SUCCESS         Capture_STATUS_SUCCESS
#define CAPTURE_STATUS_ERROR           Capture_STATUS_ERROR
#define CAPTURE_STATUS_UNDEFINEDCMD    Capture_STATUS_UNDEFINEDCMD
#define CAPTURE_MODE_RISING_RISING     Capture_RISING_EDGE
#define CAPTURE_MODE_FALLING_FALLING   Capture_FALLING_EDGE
#define CAPTURE_MODE_ANY_EDGE          Capture_ANY_EDGE
#define CAPTURE_PERIOD_US              Capture_PERIOD_US
#define CAPTURE_PERIOD_HZ              Capture_PERIOD_HZ
#define CAPTURE_PERIOD_COUNTS          Capture_PERIOD_COUNTS
#define Capture_Period_Unit            Capture_PeriodUnits

#ifdef __cplusplus
}
#endif

#endif /* ti_drivers_Capture__include */