open.c

HMS30C7202下的CAN驱动

/** open.c
 *
 * Written by Sebastian Stolzenberg email:[e-mail]
 * Version 1.0  04 Feb 2003
 */

#ifndef __KERNEL__
# define __KERNEL__
#endif
#ifndef MODULE
# define MODULE
#endif

#include <linux/module.h>
#include "../include/candrv.h"
#include "../include/hms30c7202_can.h"
#include "../include/c_can.h"
#include "../include/irq.h"

///////////////////////////////////////////////////////////////////////////////
/*
 * can_open
 *
 * Open function called by user through device file.
 * It activates one message object of the C_CAN chip and configures it to
 * to receive messages with id=0 (can be changed through ioctl).
 */

int can_open( struct inode *inode, struct file *filp )
{
        int i,j;
        struct msgobj_t *pmsgobj = NULL;
#ifdef CAN_DEBUG
        u32 intCntrVAddr = 0;
#endif

        /* Find the related msg object for this minor */
        for ( i = 0; i<pghw->cnt_tot_chips; i++ ) {
                for ( j = 0; j<pghw->pchip[ i ]->obj_cnt; j++ ) {
                        if ( pghw->pchip[ i ]->pmsgobj[ j ]->minor ==
                                MINOR( filp->f_dentry->d_inode->i_rdev )) {
                                /* We have a match */
                                if ( NULL != ( pmsgobj = pghw->pchip[ i ]->pmsgobj[ j ] ))
                                        filp->private_data = pmsgobj;
                                break;
                        }
                }
        }

        /* Check that we have a valid pointer to
           the message object info structure */
        if ( NULL == pmsgobj ) {
                CANMSG("There is no hardware support for the device file with minor nr.: %d",
                       MINOR( filp->f_dentry->d_inode->i_rdev ) );
                return -ENODEV;
        }

        /* Check to see if the message object already has been opened. */
        if ( pmsgobj->flags & CHANNEL_OPENED ) {
                CANMSG("Sorry, only single open per device file.");
                return -EBUSY;
        }

        DEBUGMSG("Opening device with minor %d", pmsgobj->minor);
        DEBUGMSG("Object Number %d of its chip", pmsgobj->object);


        /* *** We need to claim hardware to open the device ***
         *
         * Request I/O for the chip if it hasn't been done before */
        if ( pmsgobj->hostchip->active_obj_cnt < 1 ) {

                DEBUGMSG("Configuring the Hostchip of this message object");
                if ( pmsgobj->hostchip->request_io( pmsgobj->hostchip ))
                        return -ENODEV;

                pmsgobj->hostchip->active_obj_cnt++;

                /* Reset chip */
                if ( pmsgobj->hostchip->reset( pmsgobj->hostchip )) {
                        pmsgobj->hostchip->release_io( pmsgobj->hostchip );
                        pmsgobj->hostchip->active_obj_cnt--;
                        return -ENODEV;
                }

                /* Initialize statistics block */
                pmsgobj->hostchip->stat.cntRxPkt = 0;
                pmsgobj->hostchip->stat.cntRxData = 0;
                pmsgobj->hostchip->stat.cntTxPkt = 0;
                pmsgobj->hostchip->stat.cntTxData = 0;
                pmsgobj->hostchip->stat.cntWarnings = 0;
                pmsgobj->hostchip->stat.cntErrPassive = 0;
                pmsgobj->hostchip->stat.cntBusOff = 0;
                pmsgobj->hostchip->stat.cntMsgLst = 0;
                pmsgobj->hostchip->stat.cntRxFifoOvr = 0;
                pmsgobj->hostchip->stat.cntTxFifoOvr = 0;
                pmsgobj->hostchip->stat.cntStuffErr = 0;
                pmsgobj->hostchip->stat.cntFormErr = 0;
                pmsgobj->hostchip->stat.cntAckErr = 0;
                pmsgobj->hostchip->stat.cntBit0Err = 0;
                pmsgobj->hostchip->stat.cntBit1Err = 0;
                pmsgobj->hostchip->stat.cntCrcErr = 0;

                DEBUGMSG("Initializing Spinlocks");
                /* Initialize read & write fifo spinlock's */
                spin_lock_init( &pmsgobj->hostchip->spwlock );
                spin_lock_init( &pmsgobj->hostchip->sprlock );
                spin_lock_init( &pmsgobj->hostchip->if1lock );
                spin_lock_init( &pmsgobj->hostchip->if2lock );

                /* Configure the device */
                if ( pmsgobj->hostchip->flags & CHANNEL_CONFIGURED )
                        DEBUGMSG("Device is already configured.");
                else {
                        if ( pmsgobj->hostchip->chip_config( pmsgobj->hostchip )) {
                                CANMSG("Error configuring chip.");

                                /* Release I/O */
                                pmsgobj->hostchip->release_io( pmsgobj->hostchip );

                                pmsgobj->hostchip->flags &= ~CHANNEL_OPENED;
                                pmsgobj->hostchip->active_obj_cnt--;

                                return -ENODEV;
                        } else {
                                DEBUGMSG("Chip configured");
                                pmsgobj->hostchip->flags |= CHANNEL_CONFIGURED;
                        }
                }
                /* End of chip configuration */

                /* configure interrupts if chip is not run in time trig mode */
                if ( ! pmsgobj->hostchip->time_triggered ) {

#ifdef CAN_DEBUG
                        if ( !( intCntrVAddr = (u32)ioremap( 0x80024000, 0xCD ))) {
                                DEBUGMSG("Failed to map Interrupt IO-memory");
                                return -ENODEV;
                        } else
                                DEBUGMSG( "Mapped Interrupt Controller IO-memory: 0x%lx - 0x%lx to 0x%lx",
                                        (unsigned long)0X80024000,
                                        (unsigned long)0X800240CC,
                                        (unsigned long)intCntrVAddr);

                        DEBUGMSG("Interrupt Enable Register : 0x%.4lx",(long)readl(intCntrVAddr));
#endif

                        /* Request irq's */
                        DEBUGMSG("Call request_irq(%d,...)",pmsgobj->hostchip->irq);
                        if ( request_irq( pmsgobj->hostchip->irq,
                                        pmsgobj->hostchip->irq_handler,
                                        SA_SHIRQ,
                                        DEVICE_NAME,
                                        pmsgobj->hostchip )) {
                                pmsgobj->hostchip->release_io( pmsgobj->hostchip );
                                pmsgobj->hostchip->active_obj_cnt--;
                                return -ENODEV;
                        }

#ifdef CAN_DEBUG
                        DEBUGMSG("Interrupt Enable Register : 0x%.4lx",(long)readl(intCntrVAddr));
                        iounmap( (void*)intCntrVAddr);
                        DEBUGMSG( "Unmapped Interrupt Controller IO-memory: 0x%lx",
                                (unsigned long)intCntrVAddr);
#endif

                        DEBUGMSG("IRQ handler configured. %lx %x",
                                (unsigned long)pmsgobj->hostchip, pmsgobj->hostchip->irq );
                } else {
                        /* start time triggered mode */
                        start_time_trig(pmsgobj->hostchip);
                }

                pmsgobj->hostchip->flags |= CHANNEL_OPENED;

        } else {
                pmsgobj->hostchip->active_obj_cnt++;
        }


        DEBUGMSG("Initializing FIFO");

        /* Allocate memory for fifo structure */
        pmsgobj->fifo=(struct canfifo_t *)kmalloc(sizeof(struct canfifo_t),GFP_KERNEL);
        if (pmsgobj->fifo == NULL)
                return -ENOMEM;
        else
                if (add_mem_to_list(pmsgobj->fifo))
                        return -ENOMEM;

        /* Allocate output buffer memory for the opened device */
        pmsgobj->fifo->ptxbuf = (char *)kmalloc( MAX_BUF_LENGTH * sizeof(struct canmsg_t),
                                                GFP_KERNEL);

        if ( pmsgobj->fifo->ptxbuf == NULL )
                return -ENOMEM;
        else
                if ( add_mem_to_list( pmsgobj->fifo->ptxbuf ) )
                        return -ENOMEM;

        /* Allocate input buffer memory for the opened device */
        pmsgobj->fifo->prxbuf = (char *)kmalloc( MAX_BUF_LENGTH *
                                sizeof( struct canmsg_t ), GFP_KERNEL );

        if ( pmsgobj->fifo->prxbuf == NULL )
                return -ENOMEM;
        else
                if ( add_mem_to_list( pmsgobj->fifo->prxbuf ) )
                        return -ENOMEM;

        pmsgobj->flags |= CHANNEL_OPENED;

        /* In- and output buffer initialization */
        pmsgobj->fifo->txrp = pmsgobj->fifo->ptxbuf;
        pmsgobj->fifo->txwp = pmsgobj->fifo->ptxbuf;
        pmsgobj->fifo->txsize = MAX_BUF_LENGTH * sizeof( struct canmsg_t );
        pmsgobj->fifo->rxrp = pmsgobj->fifo->prxbuf;
        pmsgobj->fifo->rxwp = pmsgobj->fifo->prxbuf;
        pmsgobj->fifo->rxsize = MAX_BUF_LENGTH * sizeof( struct canmsg_t );

        init_waitqueue_head( &pmsgobj->fifo->readq );
        init_waitqueue_head( &pmsgobj->fifo->writeq );

        /* reset progress bits */
        pmsgobj->fifo->flags &= ~ ( RX_IN_PROGRESS | TX_IN_PROGRESS );
        /* allow overwriting of read buffer per default */
        pmsgobj->fifo->flags |= RD_BUFF_OVRWRT;


        pmsgobj->fifo->head = pmsgobj->fifo->tail = 0; //TEMP!!


        if ( pmsgobj->hostchip->pre_read_config( pmsgobj, 0 ) < 0 )
                CANMSG("Error initializing chip for receiving");

        MOD_INC_USE_COUNT;

        return 0;
}