ioexpander.h

IT projecotr reference design.

/****************************************************************************/
/*             TEXAS INSTRUMENTS PROPRIETARY INFORMATION                    */
/*                                                                          */
/*  (c) Copyright, Texas Instruments Incorporated, 2006.                    */
/*      All Rights Reserved.                                                */
/*                                                                          */
/*  Property of Texas Instruments Incorporated. Restricted Rights -         */
/*  Use, duplication, or disclosure is subject to restrictions set          */
/*  forth in TI's program license agreement and associated documentation.   */
/****************************************************************************/

/****************************************************************************/
/* ioExpander.h                                                             */
/*                                                                          */
/* External IO expander device interface.                                   */
/****************************************************************************/

#ifndef __IOEXPANDER_H
#define __IOEXPANDER_H

#include <stddef.h>

#include "common.h"
#include "i2c.h"

#include "iox.h"

/****************************************************************************/
/* Public IOX constants and macros.                                         */
/*                                                                          */
/****************************************************************************/

                        /****************************************************/
                        /* I2C Interface device types.                      */
                        /****************************************************/

typedef enum
{
    IOXTYPE_PCF8574A,
    IOXTYPE_PCA9539
}
    IOXTYPE;
    
                        /****************************************************/
                        /* IO Point definitions.                            */
                        /****************************************************/

#define MAXPIN      32               /* maximum number of controllable pins */

#define IOX_IN      0x80                       /* defines point as an input */
#define IOX_OUT     0x00                      /* defines point as an output */

#define IOX_TRUE    0x40                          /* defines pin state TRUE */
#define IOX_FALSE   0x00                         /* defines pin state FALSE */

#define IOX_PINMASK 0x3f             /* masks pin number in an IO point cfg */

                        /****************************************************/
                        /* Define a point configuration from pin, dir, val. */
                        /****************************************************/

#define IOX_PINCFG( pin, dir, val )  (( IOX_PINMASK & pin ) | ( dir ) | ( val ? IOX_TRUE : IOX_FALSE ))

                        /****************************************************/
                        /* Extract pin, dir, val from a point configuration */
                        /****************************************************/

#define IOX_GETPIN( pointcfg ) ( pointcfg & IOX_PINMASK )
#define IOX_GETDIR( pointcfg ) ( pointcfg & IOX_IN )
#define IOX_GETVAL( pointcfg ) ( IOX_TRUE == ( pointcfg & IOX_TRUE ))

                        /****************************************************/
                        /* IOX function completion codes.                   */
                        /****************************************************/

typedef enum
{
    IOXCC_FAIL,                                  /* general fail indication */
    IOXCC_PASS,                                                     /* pass */
    IOXCC_DEVTYPE,                                   /* invalid device type */
    IOXCC_PINNO,                         /* invalid pin count or pin number */
    IOXCC_NOTOPEN,                                       /* driver not open */
    IOXCC_PORTCFG,                            /* invalid port configuration */
    IOXCC_APIERROR                                     /* error in API call */
}
    IOXCC;

                        /****************************************************/
                        /* IOX driver initialization structure.             */
                        /****************************************************/

typedef struct
{
    IOXTYPE  xType;                                          /* driver type */
    I2CPORT  xPort;                             /* ASIC i2c controller port */
    int08    xNumPins;                         /* number of external points */
    uint32   xTimeout;                  /* semaphore timeout (milliseconds) */
}
    IOXINITSTRUCT;

                        /****************************************************/
                        /* Expander bit direction and state bitfields.      */
                        /*                                                  */
                        /* Shared between the peripheral interface and the  */
                        /* expander device drivers to eliminate i2c reads   */
                        /* to obtain current configuration and state.       */
                        /****************************************************/

extern uint32 ioxDirection;        /* direction bitfield: 0=output, 1=input */
extern uint32 ioxState;                                   /* state bitfield */



/****************************************************************************/
/* IO expander common application functions.                                */
/****************************************************************************/

EXEC_CC_ENUM iox_init( void );                 /* reset-time initialization */

IOXCC iox_open( IOXINITSTRUCT *pInit );      /* open IO expander peripheral */
IOXCC iox_cfgGet( int08 pin, uint08 *pPinCfg );     /* get an IOX point cfg */
IOXCC iox_cfgSet( uint08 pinCfg );                /* configure an IOX point */
IOXCC iox_cfgSetMult( uint08 *pPinCfg, size_t n );/* config multiple points */
IOXCC iox_pinGet( int08 pin, BOOL *pValue );      /* get an IOX point value */
IOXCC iox_pinSet( int08 pin, BOOL   value );      /* set an IOX point value */



/****************************************************************************/
/* IO expander device driver functions.                                     */
/*                                                                          */
/* Drivers provide device-specific implementation of these functions.       */
/****************************************************************************/

IOXCC   ioxdd_open( IOXINITSTRUCT *pInit );    /* open an IOX device driver */
IOXCC   ioxdd_configPin( uint08 pinCfg );                  /* configure pin */
IOXCC   ioxdd_drivePin( int08 pin, BOOL state );        /* drive output pin */
IOXCC   ioxdd_readPin( int08 pin, BOOL *state );          /* read input pin */
IOXTYPE ioxdd_type( void );                           /* return device type */

#endif