toucan.c

风河编写的摩托罗拉toucan模块的驱动代码

*
* This function clears data overrun flag for a particular channel
* Valid only for channels with mode = WNCAN_CHN_RECEIVE or
* WNCAN_CHN_RTR_REQUESTER
*
* RETURNS:        Ok or ERROR
*
* ERRNO:          S_can_illegal_channel_no, S_can_illegal_config
*
*/
static STATUS TouCAN_ClearMessageLost
(
 struct WNCAN_Device *pDev,
 UCHAR channelNum
 )
{
    
    struct canAccess *pcanAccess;   
    TouCANBuf         pTouCanBufs;
    TouCAN            pTouCanRegs;
    volatile TouCAN_StandardMsgType *buffer;
    volatile USHORT   len;
    int               retCode = ERROR; /* pessimistic */
    
    if (channelNum >= TOUCAN_MAX_MSG_OBJ)
    {
        errnoSet(S_can_illegal_channel_no);
        goto exit;
    }
    
    if((pDev->pCtrl->chnMode[channelNum] != WNCAN_CHN_RECEIVE) &&
        (pDev->pCtrl->chnMode[channelNum] != WNCAN_CHN_RTR_REQUESTER))
    {
        errnoSet(S_can_illegal_config);        
        goto exit;
    }
    
    
    /*
    * Get pointer to TouCAN registers and channels.    
    */
    pcanAccess = (struct canAccess *)pDev->pCtrl->csData;
    pTouCanRegs = (TouCAN)pcanAccess->pTouCanRegs;    
    pTouCanBufs = (TouCANBuf)pcanAccess->pTouCanBufs;               
    buffer = &pTouCanBufs->can_MSG[channelNum];         
    
    
    /*Save and later restore data length*/
    len = buffer->Control & 0x000f;
    
    /*Clear overflow code, and replace with buffer full indicaition*/
    buffer->Control = TOUCAN_BUFFER_FULL | len;
    
    retCode = OK;
    
exit:
    return retCode;
}

/************************************************************************
*
* TouCAN_IsRTR - Tests if the message has the RTR bit set. 
* The RTR bit of an incoming remote request is not stored in the channel
* registers on the TouCAN. CAN_IsRTR cannot be implemented directly. The
* TouCAN has an automatic response feature, that must be used to respond 
* to incoming remote requests.
* To do this:
* 1. Select channel mode WNCAN_CHN_RTR_RESPONDER 
* 2. On this channel call CAN_WriteID and set up matching id for incoming
*    remote request
* 3. Set up response data by calling CAN_WriteData
*
* RETURNS:        -1 
*   
* ERRNO:          S_can_use_auto_response_feature
*
*/
static int TouCAN_IsRTR
(
 struct WNCAN_Device *pDev,
 UCHAR channelNum
 )
{
    errnoSet(S_can_use_auto_response_feature);
    return -1;
}

/************************************************************************
*
* TouCAN_SetRTR - Sets RTR bit
*
* The TouCAN supports transmitting and receiving a message in the same 
* channel. The driver supports special channel modes namely 
* WNCAN_CHN_RTR_REQUESTER and WMCAN_CHN_RTR_RESPONDER to handle setting up
* RTR messages easier. 
* 
*
* RETURNS:        ERROR
*   
* ERRNO:          S_can_use_rtr_requester_channel_mode
*
*/
static STATUS TouCAN_SetRTR
(
 struct WNCAN_Device *pDev,
 UCHAR channelNum,
 BOOL  rtr
 )
{
    errnoSet(S_can_use_rtr_requester_channel_mode);
    return ERROR;
}


/************************************************************************
*
* TouCAN_TxAbort - abort the current CAN transmission
*
* This routine aborts any current CAN transmissions on the controller.
*
* RETURNS:        N/A
*
* ERRNO:          N/A
*
*/
static void TouCAN_TxAbort
(
 struct WNCAN_Device *pDev
 )
{
    struct canAccess *pcanAccess;   
    TouCANBuf         pTouCanBufs;
    volatile TouCAN_StandardMsgType *buffer;        
    UCHAR         i;      
    
    /*
    * Get pointer to TouCAN registers and channels.    
    */
    pcanAccess = (struct canAccess *)pDev->pCtrl->csData;
    pTouCanBufs = (TouCANBuf)pcanAccess->pTouCanBufs;               
    
    
    for(i=0;i<TOUCAN_MAX_MSG_OBJ;i++)
    {
        if((pDev->pCtrl->chnMode[i] == WNCAN_CHN_TRANSMIT) &&
            ~(pDev->pCtrl->chnMode[i] & WNCAN_IS_CHN_RTR))
        {
            
            buffer = &pTouCanBufs->can_MSG[i];  
            
            /*Make the channel inactive*/                
            /*
            * A write access to the control field of the channel
            * will make deactivate it, unless the message has been
            * tranferred to the serial channel.
            * However, no interrupt will be requested.
            */
            buffer->Control = 0x0080;
        }
    }
    
    return;
}


/************************************************************************
*
* TouCAN_Sleep - puts the CAN controller of the device into sleep mode
* Auto awake feature is always enabled
*
* RETURNS:        OK always
*   
* ERRNO:          N/A
*
*/
static STATUS TouCAN_Sleep
(
 struct WNCAN_Device *pDev
 )
{
    struct canAccess *pcanAccess;   
    TouCAN            pTouCanRegs;        
    USHORT            temp;
    
    /* Get pointer to TouCAN registers. */   
    pcanAccess = (struct canAccess *)pDev->pCtrl->csData;
    pTouCanRegs = (TouCAN)pcanAccess->pTouCanRegs;
    
    temp = pTouCanRegs->can_MCR;
    
    /*Enable low power stop (sleep) mode*/
    pTouCanRegs->can_MCR = (temp | TOUCAN_STOP | TOUCAN_SELFWAKE);
    
    while((pTouCanRegs->can_MCR & TOUCAN_STOPACK) != TOUCAN_STOPACK)
        ;    
    
    return OK;
}

/************************************************************************
*
* TouCAN_WakeUp - gets the CAN controller out of sleep mode
* Auto awake feature is always enabled
*
* RETURNS:        OK always
*   
* ERRNO:          N/A
*
*/
static STATUS TouCAN_WakeUp
(
 struct WNCAN_Device *pDev
 )
{
    struct canAccess *pcanAccess;   
    TouCAN            pTouCanRegs;        
    USHORT            temp;
    
    /* Get pointer to TouCAN registers. */   
    pcanAccess = (struct canAccess *)pDev->pCtrl->csData;
    pTouCanRegs = (TouCAN)pcanAccess->pTouCanRegs;
    
    temp = pTouCanRegs->can_MCR;
    
    temp &= ~(TOUCAN_STOP |TOUCAN_SELFWAKE);
    /*Disable  sleep  mode*/
    pTouCanRegs->can_MCR = temp;
    
    while((pTouCanRegs->can_MCR & TOUCAN_STOPACK) == TOUCAN_STOPACK)
        ;   
    
    return OK;
}

/************************************************************************
*
* TouCAN_GetIntStatus - get the interrupt status on the controller
*
* This function returns the interrupt status on the controller: 
*
*    WNCAN_INT_NONE     = no interrupt occurred
*    WNCAN_INT_ERROR    = bus error
*    WNCAN_INT_TX       = interrupt resuting from a CAN transmission
*    WNCAN_INT_RX       = interrupt resulting form message reception
*    WNCAN_INT_BUS_OFF  = interrupt resulting from bus off condition
*    WNCAN_INT_WAKE_UP  = interrupt resulting from controller waking up
*                         after being put in sleep mode
*    WNCAN_INT_SPURIOUS = unknown interrupt
*
* NOTE: If the interrupt was caused by the transmission or reception of a 
* message, the channel number that generated the interrupt is set; otherwise,
* this value is undefined.

 * ERRNO: N/A
 *
*/
static WNCAN_IntType TouCAN_GetIntStatus
(
 struct WNCAN_Device *pDev,
 UCHAR *channelNum
 )
{
    WNCAN_IntType   intStatus = WNCAN_INT_NONE;
    struct canAccess *pcanAccess;
    TouCAN            pTouCanRegs;
    TouCANBuf         pTouCanBufs;
    volatile TouCAN_StandardMsgType *buffer;
    volatile USHORT   regInt;
    volatile USHORT   msgCode;
    volatile USHORT   statusTemp;
    
    /*
    * Get pointer to TouCAN registers and channels.    
    */
    pcanAccess = (struct canAccess *)pDev->pCtrl->csData;
    pTouCanRegs = (TouCAN)pcanAccess->pTouCanRegs;              
    pTouCanBufs = (TouCANBuf)pcanAccess->pTouCanBufs;
    
    /*
    * And the interrupt register and the interrupt mask register    
    */
    regInt = pTouCanRegs->can_IFLAG & pTouCanRegs->can_IMASK;
    statusTemp = pTouCanRegs->can_ESTAT; 
    
    if(regInt == 0)
    {
        if(pTouCanRegs->can_CR0 & TOUCAN_ERROR_MASK_ENABLE)
        {
            if( statusTemp & TOUCAN_ERRINT)
            {
                intStatus = WNCAN_INT_ERROR;
            }
            
        }
        
        if(pTouCanRegs->can_CR0 & TOUCAN_BOFF_MASK_ENABLE)
        {
            if( statusTemp & TOUCAN_BOFFINT)
            {
                intStatus = WNCAN_INT_ERROR;
            }
        }
        
        if(pTouCanRegs->can_MCR & TOUCAN_WAKEUPINT_ENABLE)
        {
            if( statusTemp & TOUCAN_WAKEINT)
            {
                intStatus = WNCAN_INT_WAKE_UP;
                
            }
            
        }
        
    }
    else
    {
        for(*channelNum = 0; *channelNum < TOUCAN_MAX_MSG_OBJ ; ++*channelNum)
        {
            if( regInt & (1 << *channelNum))
            {
                buffer = &pTouCanBufs->can_MSG[*channelNum];        
                msgCode = buffer->Control & 0x00f0;
                
                
                /*
                * Check in case busy bit is set. May be set if a
                * response to remote request is being transferred from the
                * serial buffer. Busy bit should not be set for a data rx,
                * as we poll the IFLAG register before accessing the channel.
                * If set, return error.
                */
                if(msgCode & TOUCAN_BUFFER_BUSY) {
                    /*break as channel is busy*/
                    break;
                }
                
                
                switch(msgCode) {
                case TOUCAN_BUFFER_FULL:
                    intStatus = WNCAN_INT_RX;
                    break;
                case TOUCAN_RESPONSE_TO_REMOTE:                         
                    intStatus = WNCAN_INT_RTR_RESPONSE;
                    break;                  
                case  TOUCAN_TX_NOT_READY:
                    intStatus = WNCAN_INT_TX;
                    break;
                case TOUCAN_BUFFER_OVERRUN:
                    intStatus = WNCAN_INT_ERROR;
                    break;
                case TOUCAN_BUFFER_READY_TO_RX:
                    intStatus = WNCAN_INT_TX;                        
                    break;
                default:
                    /*To add errnoset to flag a fatal error*/
                    intStatus = WNCAN_INT_NONE;
                }                
            }
        }
        
        /* Read the free running timer to unlock the controller */
        timerRead = pTouCanRegs->can_TIMER;
    }
    
    
    return intStatus;
}        


/************************************************************************
*
* TouCANISR - interrupt service routine 
*
* RETURNS: N/A
*   
* ERRNO: N/A
*
*/
void TouCANISR
(
 ULONG context
 )
{
    WNCAN_IntType      intStatus;
    struct WNCAN_Device  *pDev;
    struct canAccess     *pcanAccess;
    TouCAN               pTouCanRegs;        
    TouCANBuf            pTouCanBufs;
    volatile TouCAN_StandardMsgType *buffer;    
    volatile USHORT      regInt;
    volatile USHORT      msgCode;
    volatile USHORT      statusTemp;
    UCHAR                chnNum=16;
    
    /*
    * Get pointer to TouCAN registers and channels.    
    */
    
    if ((pDev = (struct WNCAN_Device *)context) == NULL) return;
    pcanAccess  = (struct canAccess *)pDev->pCtrl->csData;
    pTouCanRegs = (TouCAN)pcanAccess->pTouCanRegs;              
    pTouCanBufs = (TouCANBuf)pcanAccess->pTouCanBufs;
    
    while(1)
    {
        /* And the interrupt register and the interrupt mask register */  
        intStatus  = WNCAN_INT_NONE;
        regInt     = pTouCanRegs->can_IFLAG & pTouCanRegs->can_IMASK;
        statusTemp = pTouCanRegs->can_ESTAT; 
        
        if(regInt == 0) {
            if(pTouCanRegs->can_CR0 & TOUCAN_ERROR_MASK_ENABLE)
            {
                if( statusTemp & TOUCAN_ERRINT)
                {
                    intStatus = WNCAN_INT_ERROR;
                    
                    /*
                    * Clear the error interrupt bit in the ESTAT register 
                    * by reading it as a 1 and writing a 0
                    */
                    pTouCanRegs->can_ESTAT &= ~(TOUCAN_ERRINT);
                }
                
            }
            
            if(pTouCanRegs->can_CR0 & TOUCAN_BOFF_MASK_ENABLE)
            {
                if( statusTemp & TOUCAN_BOFFINT)
                {
                    intStatus = WNCAN_INT_ERROR;
                    /*
                    * Clear the BUS OFF interrupt bit in the ESTAT register 
                    * by reading it as a 1 and writing a 0
                    */
                    pTouCanRegs->can_ESTAT &= ~(TOUCAN_BOFFINT);
                    
                }
            }
            
            if(pTouCanRegs->can_MCR & TOUCAN_WAKEUPINT_ENABLE)
            {
                if( statusTemp & TOUCAN_WAKEINT)
                {
                    intStatus = WNCAN_INT_WAKE_UP;
                    
                    /*
                    * Clear the error interrupt bit in the ESTAT register 
                    * by reading it as a 1 and writing a 0
                    */
                    pTouCanRegs->can_ESTAT &= ~(TOUCAN_WAKEINT);
                }
                
            }
            
        } else {
            /* Find the channel with the highest pending interrupt */
            for(chnNum = 0; chnNum < TO