iic_saa9730.c

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 *
 *  Check status and control register for any detected errors.
 *
 *
 *  Parameters :
 *  ------------
 *
 *  -
 *
 *  Return values :
 *  ---------------
 *
 *  'OK' = 0x00:              IIC service completed successfully
 *  ERROR_IIC_ADDRESS_ERROR:  IIC address error
 *  ERROR_IIC_DATA_ERROR:     IIC data error
 *
 *
 ************************************************************************/
static 
INT32 IIC_SAA9730_check( void ) ;


/************************************************************************
 *
 *                          IIC_SAA9730_get_data
 *  Description :
 *  -------------
 *
 *  Get data from BYTE2, BYTE1 and BYTE0 of Transfer Register and
 *  save it in user allocated buffer space.
 *  
 *
 *  Parameters :
 *  ------------
 *
 *  -
 *
 *
 *  Return values :
 *  ---------------
 *
 *  -
 *
 ************************************************************************/
static 
void IIC_SAA9730_get_data( void ) ;


/************************************************************************
 *
 *                          IIC_SAA9730_flush
 *  Description :
 *  -------------
 *
 *  Flush out any command or data of command buffer into Transfer
 *  Register.
 *  
 *
 *  Parameters :
 *  ------------
 *
 *  -
 *
 *  Return values :
 *  ---------------
 *
 *  'OK' = 0x00:              IIC service completed successfully
 *  ERROR_IIC_ADDRESS_ERROR:  IIC address error
 *  ERROR_IIC_DATA_ERROR:     IIC data error
 *  ERROR_IIC_TIMEOUT:        IIC service timed-out
 * 
 ************************************************************************/
static 
INT32 IIC_SAA9730_flush( void ) ;


/************************************************************************
 *
 *                          IIC_SAA9730_add
 *  Description :
 *  -------------
 *
 *  Add another data byte to command buffer and flush in case
 *  command buffer gets full.
 *  
 *
 *  Parameters :
 *  ------------
 *  'data':                   pointer for next data byte to add
 *  'attrib':                 either 'nop', 'start', 'cont', 'stop'
 *  'read':                   'true' by read, 'false' by 'write'.
 *
 *
 *  Return values :
 *  ---------------
 *
 *  'OK' = 0x00:              IIC service completed successfully
 *  ERROR_IIC_ADDRESS_ERROR:  IIC address error
 *  ERROR_IIC_DATA_ERROR:     IIC data error
 *  ERROR_IIC_TIMEOUT:        IIC service timed-out
 *
 *
 ************************************************************************/
static 
INT32 IIC_SAA9730_add( UINT8 *data,
                       UINT8 attrib,
                       UINT8 read ) ;


/************************************************************************
 *
 *                          IIC_SAA9730_wait
 *  Description :
 *  -------------
 *  
 *  Await IIC-bus operation being completed
 *  
 *
 *  Parameters :
 *  ------------
 *
 *  -
 *
 *
 *  Return values :
 *  ---------------
 *
 *  'OK' = 0x00:              IIC service completed successfully
 *  'ERROR_IIC_TIMEOUT'       IIC service timed-out
 *
 *
 ************************************************************************/
static 
INT32 IIC_SAA9730_wait( void ) ;


/************************************************************************
 *      Implementation : Public functions
 ************************************************************************/


/************************************************************************
 *
 *                          IIC_SAA9730_install
 *  Description :
 *  -------------
 *
 *  Installs the IIC SAA9730 device drivers services in 
 *  the IO system at the reserved device slot, found in the
 *  'sysdev.h' file, which defines all major device numbers.
 *
 *  Note:
 *  This service is the only public declared interface function; all
 *  provided device driver services are static declared, but this
 *  function installs the function pointers in the io-system to
 *  enable the provided public driver services.
 *
 *  Parameters :
 *  ------------
 *
 *  -
 *
 *
 *  Return values :
 *  ---------------
 *
 *  'OK'(=0)
 *  'ERROR_IO_ILLEGAL_MAJOR':  Illegal major device number
 *  'ERROR_IO_NO_SPACE':       Device slot already allocated
 *
 ************************************************************************/
INT32 IIC_SAA9730_install( void )
{
	/* pre-initialize local variables and install device services */
	IO_install( SYS_MAJOR_IIC,                /* major device number */
         (t_io_service) IIC_SAA9730_init,         /* 'init'  service     */
                        NULL,                     /* 'open'  service  na */
                        NULL,                     /* 'close' service  na */
         (t_io_service) IIC_SAA9730_read,         /* 'read'  service     */
         (t_io_service) IIC_SAA9730_write,        /* 'write' service     */
         (t_io_service) IIC_SAA9730_ctrl ) ;      /* 'ctrl'  service     */

	/* call our own 'init' service */
	return IO_init( SYS_MAJOR_IIC, 0, NULL);
}



/************************************************************************
 *      Implementation : Static functions
 ************************************************************************/


/************************************************************************
 *
 *                          IIC_SAA9730_init
 *  Description :
 *  -------------
 *  This service initializes the IIC driver and configures
 *  the IIC-bus speed via the 'syscon' parameter:
 *
 *  'SYSCON_COM_IIC_BAUDRATE_ID'
 *  
 *
 *  Parameters :
 *  ------------
 *
 *  'major',     IN,    major device number
 *  'minor',     IN,    not used
 *  'p_param',   INOUT, not used
 *
 *
 *  Return values :
 *  ---------------
 *
 *  'OK'(=0)
 *
 *
 *
 ************************************************************************/
static
INT32 IIC_SAA9730_init(
          UINT32 major,          /* IN: major device number             */
          UINT32 minor,          /* IN: minor device number             */
          void   *p_param )      /* INOUT: device parameter block       */
{
    int rcode ;

    /* get base for SAA9730 */
    rcode = SYSCON_read( SYSCON_BOARD_SAA9730_BASE_ID,
                         &saa9730base,
                         sizeof(saa9730base) ) ;

    saa9730base = (void *)KSEG1( saa9730base );

    /* reset command buffer */
    IIC_SAA9730_reset() ;

    /* STC-register: set speed = 103.125 KHz */
    REG(saa9730base, IIC_STC) = IIC_STC_CLK_103125HZ << IIC_STC_CLK_SHF;

    return( rcode ) ;
}

/************************************************************************
 *
 *                          IIC_SAA9730_read
 *  Description :
 *  -------------
 *  This service reads data from the specified IIC device into the
 *  user allocated variable, *p_param.
 *
 *  Parameters :
 *  ------------
 *
 *  'major',     IN,    major device number
 *  'minor',     IN,    minor device number for multi device drivers
 *  'p_param',   INOUT, variable of type, t_IIC_read_descriptor.
 *
 *
 *  Return values :
 *  ---------------
 *
 *  'OK' = 0x00:              IIC device data read into user variable
 *  'ERROR_IIC_COMM_ERROR':   communication error detected
 *
 *
 ************************************************************************/
static
INT32 IIC_SAA9730_read(
          UINT32 major,          /* IN: major device number             */
          UINT32 minor,          /* IN: minor device number             */
          t_IIC_read_descriptor *p_param )   /* INOUT: read buffer      */
{
    int i, rcode ;
    UINT8 addr;
    UINT8 *rdbuf ;

    /* Prepare IIC-read: set slave address and 'read' flag */
    addr = ((p_param->IICaddress) << 1) | 0x01 ; 

    /* Start IIC-read operation */
    rcode = IIC_SAA9730_add( &addr, IIC_TFR_BYTEATTR_START, IIC_WRITECMD) ;
    if (rcode != OK) return( rcode ) ;

    /* Continue IIC-read operation */
    rdbuf = p_param->buffer ; 
    for (i = 1; i < p_param->length ; i++)
    {
        rcode = IIC_SAA9730_add(rdbuf++, IIC_TFR_BYTEATTR_CONT, IIC_READCMD);
        if (rcode != OK) return( rcode ) ;
    }

    /* Complete IIC-read operation */
    rcode = IIC_SAA9730_add(rdbuf, IIC_TFR_BYTEATTR_STOP, IIC_READCMD);
    if (rcode != OK) return( rcode ) ;

    /* Get any remaining received data in command buffer */
    rcode = IIC_SAA9730_flush() ;
    return( rcode ) ;
}

/************************************************************************
 *
 *                          IIC_SAA9730_write
 *  Description :
 *  -------------
 *  This service writes user data to the specified IIC device.
 *
 *  
 *
 *  Parameters :
 *  ------------
 *
 *  'major',     IN,    major device number
 *  'minor',     IN,    minor device number for multi device drivers
 *  'p_param',   INOUT, variable of type, t_IIC_write_descriptor.
 *
 *
 *  Return values :
 *  ---------------
 *
 *  'OK' = 0x00:              IIC service completed successfully
 *  'ERROR_IIC_COMM_ERROR':   communication error detected
 *
 *
 ************************************************************************/
static
INT32 IIC_SAA9730_write(
          UINT32 major,          /* IN: major device number             */
          UINT32 minor,          /* IN: minor device number             */
          t_IIC_write_descriptor *p_param )   /* IN: write buffer       */
{
    int i, rcode ;
    UINT8 addr;
    UINT8 *wrbuf ;

    /* Prepare IIC-write: set slave address and 'write' condition */
    addr = ((p_param->IICaddress) << 1) & 0xFE ; 

    /* Start IIC-write operation */
    rcode = IIC_SAA9730_add( &addr, IIC_TFR_BYTEATTR_START, IIC_WRITECMD) ;
    if (rcode != OK) return( rcode ) ;

    /* Continue IIC-write operation */
    wrbuf = p_param->buffer ; 
    for (i = 1; i < p_param->length ; i++)
    {
        rcode = IIC_SAA9730_add(wrbuf++, IIC_TFR_BYTEATTR_CONT, IIC_WRITECMD);
        if (rcode != OK) return( rcode ) ;
    }

    /* Complete IIC-write operation */
    rcode = IIC_SAA9730_add(wrbuf, IIC_TFR_BYTEATTR_STOP, IIC_WRITECMD);
    if (rcode != OK) return( rcode ) ;

    /* Flush any remaining data in command buffer */
    rcode = IIC_SAA9730_flush() ;

    /*  Wait until write has finished */
    if (rcode == OK)
    {
        rcode = -1 ;
        while (rcode != OK)
        {
            IIC_SAA9730_add( &addr, IIC_TFR_BYTEATTR_START, IIC_WRITECMD) ;
            IIC_SAA9730_add( &addr, IIC_TFR_BYTEATTR_STOP, IIC_WRITECMD);
            rcode = IIC_SAA9730_flush() ;
        }
    }
    return( rcode ) ;
}


/************************************************************************
 *
 *                          IIC_SAA9730_ctrl
 *  Description :
 *  -------------
 *  This service comprise following aggregated IIC services:
 *   1) 'write_read' IIC device.
 *   2) 'test'       IIC device.
 *
 *  
 *
 *  Parameters :
 *  ------------
 *
 *  'major',     IN,    major device number
 *  'minor',     IN,    minor device number for multi device drivers
 *  'p_param',   INOUT, variable of type, t_IIC_ctrl_descriptor.
 *
 *
 *  Return values :
 *  ---------------
 *
 *  'OK' = 0x00:              IIC service completed successfully
 *  'ERROR_IIC_COMM_ERROR':   communication error detected
 *
 *
 ************************************************************************/
static
INT32 IIC_SAA9730_ctrl(
          UINT32 major,          /* IN: major device number             */
          UINT32 minor,          /* IN: minor device number             */
          t_IIC_ctrl_descriptor *p_param )   /* INOUT: IIC device data  */
{
    int i, rcode ;
    t_IIC_write_read_descriptor *wrd ;
    UINT8 addr;
    UINT8 *buffer ;