i2c.c

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/*****************************************************************************
File Name   : i2c.c

Description : Wrapper layer for STI2C.

Copyright (C) 2000 STMicroelectronics

Revision History    :

    10/02/00        Created module to hide STAPI I2C dependency from
                    all low-level components that are required to use
                    the I2C bus.

Reference           :

*****************************************************************************/

/* Includes --------------------------------------------------------------- */

#include <string.h>                     /* C libs */ 
#include <stdio.h>

#include "stlite.h"                     /* Standard includes */
#include "stddefs.h"

#include "i2c.h"                        /* I2C wrapper layer include */
#include "sti2c.h"                      /* STI2C include */

/* Private types/constants ------------------------------------------------ */

/* Private variables ------------------------------------------------------ */

/* Private macros --------------------------------------------------------- */

#define I2C_HANDLE(x)   (*((STI2C_Handle_t *)x))

/* Private function prototypes -------------------------------------------- */

/* API routines ----------------------------------------------------------- */

/*****************************************************************************
Name: I2C_Transfer()
Description:
    Performs and I2C transfer i.e., a read or write with or without a prefix
    1 byte subaddress.
Parameters:
    Handle,         pointer to a STI2C_Handle_t.
    Operation,      determinates the operation type required.
    SubAddr,        subaddress of slave device to communicate with - only
                    applicable to I2C_SUBADDR_XXXX operations.
    TransferSize,   number of bytes to read or write.
    Timeout,        operation timeout in milliseconds.
                    0 => wait forever.
Return Value:
    ST_NO_ERROR,    The operation completed withouth error.
    STI2C_xxxx,     I2C error.
See Also:
    I2C_Operation_t
*****************************************************************************/

ST_ErrorCode_t I2C_Transfer(void *Handle,
                            I2C_Operation_t Operation,
                            U8 SubAddr,
                            U8 *Data,
                            U32 TransferSize,
                            U32 Timeout)
{
    ST_ErrorCode_t Error = ST_NO_ERROR;
    U32 Size;

    switch ( Operation )
    {
        case I2C_SUBADDR_READ:
            Error = STI2C_WriteNoStop(I2C_HANDLE(Handle),
                                      &SubAddr,
                                      1,
                                      Timeout,
                                      &Size);
        case I2C_READ:
            if (Error == ST_NO_ERROR)
                Error = STI2C_Read(I2C_HANDLE(Handle),
                                   Data,
                                   TransferSize,
                                   Timeout,
                                   &Size);
            break;
        case I2C_SUBADDR_WRITE:
            Error = STI2C_WriteNoStop(I2C_HANDLE(Handle),
                                      &SubAddr,
                                      1,
                                      Timeout,
                                      &Size);
        case I2C_WRITE:
            if (Error == ST_NO_ERROR)
                Error = STI2C_Write(I2C_HANDLE(Handle),
                                    Data,
                                    TransferSize,
                                    Timeout,
                                    &Size);
            break;
        default:
            break;
    }

    return Error;
} /* I2C_Transfer() */

/* End of i2c.c */