drivers/can_can4linux/can_can4linux.c
author etisserant
Thu, 31 Jan 2008 15:20:59 +0100
changeset 375 03fb0bfccc1f
parent 365 9b76e0881beb
child 384 83793fc7ce48
permissions -rwxr-xr-x
AVR port, thanks to Peter Christen, Comat AG.
/*
This file is part of CanFestival, a library implementing CanOpen Stack.

Copyright (C): Jorge BERZOSA

See COPYING file for copyrights details.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/*
* can4linux driver
*/

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>

#include "can4linux.h" 
#include "can_driver.h"

struct timeval init_time,current_time;

/*********functions which permit to communicate with the board****************/
UNS8 canReceive_driver(CAN_HANDLE fd0, Message *m)
{
  int res,i;
  canmsg_t canmsg;
  long int time_period;

	canmsg.flags = 0; 
	do{
   		res = read(fd0,&canmsg,1);
   		if((res<0)&&(errno == -EAGAIN)) res = 0;
	}while(res==0);

	if(res !=1) // No new message
   	return 1;

	if(canmsg.flags&MSG_EXT){
   		/* There is no mark for extended messages in CanFestival */;
	}
  		
	m->cob_id = canmsg.id;
	m->len = canmsg.length;
	if(canmsg.flags&MSG_RTR){
 		m->rtr = 1;
	}else{
 		m->rtr = 0;
 		memcpy(m->data,canmsg.data,8);
	}
	
	
 	/*gettimeofday(&current_time,NULL);
 	time_period=(current_time.tv_sec - init_time.tv_sec)* 1000000 + current_time.tv_usec - init_time.tv_usec;
 	printf("%3ld.%3ld.%3ld - Receive ID: %lx ->",time_period/1000000,(time_period%1000000)/1000,time_period%1000,m->cob_id);
 	printf("Receive ID: %lx ->",m->cob_id);
 	for(i=0; i<canmsg.length;i++)printf("%x, ", m->data[i]);
 	printf("\n");*/
 
  return 0;
}

/***************************************************************************/
UNS8 canSend_driver(CAN_HANDLE fd0, Message *m)
{
  int res;
  canmsg_t canmsg;

  canmsg.flags = 0;
  canmsg.id = m->cob_id;
  canmsg.length = m->len;
  if(m->rtr){
    canmsg.flags |= MSG_RTR;
  }else{
    memcpy(canmsg.data,m->data,8);
  }
  
 /*printf("Send ID: %lx ->",canmsg.id); 
 for(i=0; i<canmsg.length;i++)printf("%x, ", canmsg.data[i]);
 printf("\n");*/

  if(canmsg.id >= 0x800){
    canmsg.flags |= MSG_EXT;
  }

  res = write(fd0,&canmsg,1);
  if(res!=1)
    return 1;

  return 0;
}

/***************************************************************************/
int	set_bitrate( CAN_HANDLE fd, int baud)
{
    Config_par_t  cfg;	
    volatile Command_par_t cmd;

    cmd.cmd = CMD_STOP;
    ioctl(fd, COMMAND, &cmd);

    cfg.target = CONF_TIMING; 
    cfg.val1   = baud;
    ioctl(fd, CONFIG, &cfg);

    cmd.cmd = CMD_START;
    ioctl(fd, COMMAND, &cmd);
    return 0;
}

/***************************************************************************/
int TranslateBaudeRate(char* optarg){
	if(!strcmp( optarg, "1M")) return (int)1000;
	if(!strcmp( optarg, "500K")) return (int)500;
	if(!strcmp( optarg, "250K")) return (int)250;
	if(!strcmp( optarg, "125K")) return (int)125;
	if(!strcmp( optarg, "100K")) return (int)100;
	if(!strcmp( optarg, "50K")) return (int)50;
	if(!strcmp( optarg, "20K")) return (int)20;
	if(!strcmp( optarg, "10K")) return (int)10;
	if(!strcmp( optarg, "5K")) return (int)5;
	if(!strcmp( optarg, "none")) return 0;
	return 0x0000;
}

/***************************************************************************/
static const char lnx_can_dev_prefix[] = "/dev/can";

CAN_HANDLE canOpen_driver(s_BOARD *board)
{
  int name_len = strlen(board->busname);
  int prefix_len = strlen(lnx_can_dev_prefix);
  char dev_name[prefix_len+name_len+1];
  int o_flags = 0;
  int baud = TranslateBaudeRate(board->baudrate);
  int fd0;

  
  /*o_flags = O_NONBLOCK;*/

  memcpy(dev_name,lnx_can_dev_prefix,prefix_len);
  memcpy(dev_name+prefix_len,board->busname,name_len);
  dev_name[prefix_len+name_len] = 0;

  fd0 = open(dev_name, O_RDWR|o_flags);
  if(fd0 <= 0){
    fprintf(stderr,"!!! %s is unknown. See can4linux.c\n", dev_name);
    goto error_ret;
  }
  
  set_bitrate((CAN_HANDLE)fd0, baud);

  printf("CAN device dev/can%s opened. Baudrate=>%s\n",board->busname, board->baudrate);

  return (CAN_HANDLE)fd0;

 error_ret:
  return NULL;
}

/***************************************************************************/
int canClose_driver(CAN_HANDLE fd0)
{
  if((int)fd0<=0)
    return -1;
  close(fd0);
  return 0;
}