nuttx-apps/canutils/libobd2/obd2.c
2018-08-13 07:47:26 -06:00

127 lines
4.0 KiB
C

/****************************************************************************
* canutils/libobd2/obd2.c
*
* Copyright (C) 2017 Alan Carvalho de Assis. All rights reserved.
* Author: Alan Carvalho de Assis <acassis@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/ioctl.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <nuttx/can/can.h>
#include "canutils/obd.h"
#include "canutils/obd_pid.h"
#include "canutils/obd_frame.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: obd_init
*
* Description:
* Initialize the OBD-II with initial baudrate
*
* Returns a obd_dev_s with initial values or NULL if error.
*
****************************************************************************/
struct obd_dev_s *obd_init(char *devfile, int baudate, int mode)
{
struct obd_dev_s *dev;
int ret;
/* Alloc memory for this device */
dev = malloc(sizeof(struct obd_dev_s));
if (!dev)
{
printf("ERROR: Failed to alloc memory for obd_dev!\n");
return NULL;
}
/* Open the CAN device for reading/writing */
dev->can_fd = open(devfile, O_RDWR);
if (dev->can_fd < 0)
{
printf("ERROR: open %s failed: %d\n", devfile, errno);
return NULL;
}
/* Show bit timing information if provided by the driver. Not all CAN
* drivers will support this IOCTL.
*/
ret = ioctl(dev->can_fd, CANIOC_GET_BITTIMING,
(unsigned long)((uintptr_t)&dev->can_bt));
if (ret < 0)
{
printf("Bit timing not available: %d\n", errno);
return NULL;
}
else
{
printf("Bit timing:\n");
printf(" Baud: %lu\n", (unsigned long)dev->can_bt.bt_baud);
printf(" TSEG1: %u\n", dev->can_bt.bt_tseg1);
printf(" TSEG2: %u\n", dev->can_bt.bt_tseg2);
printf(" SJW: %u\n", dev->can_bt.bt_sjw);
}
/* FIXME: Setup the baudrate */
/* Setup the initial mode */
if (mode != CAN_STD && mode != CAN_EXT)
{
printf("ERROR: Invalid mode, it needs to be CAN_STD or CAN_EXT!\n");
return NULL;
}
dev->can_mode = mode;
printf("OBD-II device initialized!\n");
return dev;
}