nuttx-apps/canutils/canlib/canlib_setloopback.c
2017-05-12 11:58:57 -03:00

91 lines
3.3 KiB
C

/****************************************************************************
* canutils/canlib/canlib_setloopback.c
*
* Copyright (C) 2016 Sebastien Lorquet. All rights reserved.
* Author: Sebastien Lorquet <sebastien@lorquet.fr>
*
* 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 <stdbool.h>
#include <fcntl.h>
#include <errno.h>
#include <nuttx/can/can.h>
/****************************************************************************
* Name: canlib_setloopback
*
* Description:
* Wrapper for CANIOC_SET_CONNMODES. When loopback mode is enabled, the CAN
* peripheral transmits on the bus, but only receives its own sent messages.
*
* Input Parameter:
* fd - file descriptor of an opened can device
* loopback - wether to use loopback mode.
*
* Returned Value:
* Zero (OK) is returned on success. Otherwise -1 (ERROR)
* is returned with the errno variable set to indicate the
* nature of the error.
*
****************************************************************************/
int canlib_setloopback(int fd, bool loopback)
{
int ret;
struct canioc_connmodes_s connmodes;
ret = ioctl(fd, CANIOC_GET_CONNMODES, (unsigned long)&connmodes);
if (ret != OK)
{
canerr("CANIOC_GET_CONNMODES failed, errno=%d\n", errno);
return ret;
}
connmodes.bm_loopback = !!loopback;
ret = ioctl(fd, CANIOC_SET_CONNMODES, (unsigned long)&connmodes);
if (ret != OK)
{
canerr("CANIOC_SET_CONNMODES failed, errno=%d\n", errno);
}
return ret;
}