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/* Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of The Linux Foundatoin, 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 "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
* 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.
*/
#include <errno.h>
#include <sys/time.h>
#include <sys/ioctl.h>
#include <linux/types.h>
#include <linux/pps.h>
#ifndef _TIMEPPS_H
#define _TIMEPPS_H
#ifdef __cplusplus
extern "C" {
#endif
/* time of assert event */
typedef struct timespec pps_info;
/* represents pps source */
typedef int pps_handle;
/* Open the PPS source */
static __inline int pps_create(int source, pps_handle *handle)
{
int ret;
struct pps_kparams dummy;
if (!handle)
{
errno = EINVAL;
return -1;
}
/* check if current device is valid pps */
ret = ioctl(source, PPS_GETPARAMS, &dummy);
if (ret)
{
errno = EOPNOTSUPP;
return -1;
}
*handle = source;
return 0;
}
/* close the pps source */
static __inline int pps_destroy(pps_handle handle)
{
return close(handle);
}
/*reads timestamp from pps device*/
static __inline int pps_fetch(pps_handle handle, const int tsformat,
pps_info *ppsinfobuf,
const struct timespec *timeout)
{
struct pps_fdata fdata;
int ret;
if (tsformat != PPS_TSFMT_TSPEC)
{
errno = EINVAL;
return -1;
}
if (timeout)
{
fdata.timeout.sec = timeout->tv_sec;
fdata.timeout.nsec = timeout->tv_nsec;
fdata.timeout.flags = ~PPS_TIME_INVALID;
}
else
{
fdata.timeout.flags = PPS_TIME_INVALID;
}
ret = ioctl(handle, PPS_FETCH, &fdata);
ppsinfobuf->tv_sec = fdata.info.assert_tu.sec;
ppsinfobuf->tv_nsec = fdata.info.assert_tu.nsec;
return ret;
}
#ifdef __cplusplus
}
#endif
#endif
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