diff options
Diffstat (limited to 'refclock_pps.c')
-rw-r--r-- | refclock_pps.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/refclock_pps.c b/refclock_pps.c new file mode 100644 index 0000000..85ff9e9 --- /dev/null +++ b/refclock_pps.c @@ -0,0 +1,169 @@ +/* + chronyd/chronyc - Programs for keeping computer clocks accurate. + + ********************************************************************** + * Copyright (C) Miroslav Lichvar 2009 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program 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 + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + ********************************************************************** + + ======================================================================= + + PPSAPI refclock driver. + + */ + +#include "config.h" + +#include "refclock.h" + +#if FEAT_PPS + +#if defined(HAVE_SYS_TIMEPPS_H) +#include <sys/timepps.h> +#elif defined(HAVE_TIMEPPS_H) +#include <timepps.h> +#endif + +#include "logging.h" +#include "memory.h" +#include "util.h" + +struct pps_instance { + pps_handle_t handle; + pps_seq_t last_seq; + int edge_clear; +}; + +static int pps_initialise(RCL_Instance instance) { + pps_handle_t handle; + pps_params_t params; + struct pps_instance *pps; + int fd, edge_clear, mode; + char *path; + + path = RCL_GetDriverParameter(instance); + edge_clear = RCL_GetDriverOption(instance, "clear") ? 1 : 0; + + fd = open(path, O_RDWR); + if (fd < 0) { + LOG_FATAL("Could not open %s : %s", path, strerror(errno)); + return 0; + } + + UTI_FdSetCloexec(fd); + + if (time_pps_create(fd, &handle) < 0) { + LOG_FATAL("time_pps_create() failed on %s : %s", path, strerror(errno)); + return 0; + } + + if (time_pps_getcap(handle, &mode) < 0) { + LOG_FATAL("time_pps_getcap() failed on %s : %s", path, strerror(errno)); + return 0; + } + + if (time_pps_getparams(handle, ¶ms) < 0) { + LOG_FATAL("time_pps_getparams() failed on %s : %s", path, strerror(errno)); + return 0; + } + + if (!edge_clear) { + if (!(mode & PPS_CAPTUREASSERT)) { + LOG_FATAL("CAPTUREASSERT not supported on %s", path); + return 0; + } + params.mode |= PPS_CAPTUREASSERT; + params.mode &= ~PPS_CAPTURECLEAR; + } else { + if (!(mode & PPS_CAPTURECLEAR)) { + LOG_FATAL("CAPTURECLEAR not supported on %s", path); + return 0; + } + params.mode |= PPS_CAPTURECLEAR; + params.mode &= ~PPS_CAPTUREASSERT; + } + + if (time_pps_setparams(handle, ¶ms) < 0) { + LOG_FATAL("time_pps_setparams() failed on %s : %s", path, strerror(errno)); + return 0; + } + + + pps = MallocNew(struct pps_instance); + pps->handle = handle; + pps->last_seq = 0; + pps->edge_clear = edge_clear; + + RCL_SetDriverData(instance, pps); + return 1; +} + +static void pps_finalise(RCL_Instance instance) +{ + struct pps_instance *pps; + + pps = (struct pps_instance *)RCL_GetDriverData(instance); + time_pps_destroy(pps->handle); + Free(pps); +} + +static int pps_poll(RCL_Instance instance) +{ + struct pps_instance *pps; + struct timespec ts; + pps_info_t pps_info; + pps_seq_t seq; + + pps = (struct pps_instance *)RCL_GetDriverData(instance); + + ts.tv_sec = 0; + ts.tv_nsec = 0; + + if (time_pps_fetch(pps->handle, PPS_TSFMT_TSPEC, &pps_info, &ts) < 0) { + LOG(LOGS_ERR, "time_pps_fetch() failed : %s", strerror(errno)); + return 0; + } + + if (!pps->edge_clear) { + seq = pps_info.assert_sequence; + ts = pps_info.assert_timestamp; + } else { + seq = pps_info.clear_sequence; + ts = pps_info.clear_timestamp; + } + + if (seq == pps->last_seq || UTI_IsZeroTimespec(&ts)) { + DEBUG_LOG("PPS sample ignored seq=%lu ts=%s", + (unsigned long)seq, UTI_TimespecToString(&ts)); + return 0; + } + + pps->last_seq = seq; + + return RCL_AddPulse(instance, &ts, 1.0e-9 * ts.tv_nsec); +} + +RefclockDriver RCL_PPS_driver = { + pps_initialise, + pps_finalise, + pps_poll +}; + +#else + +RefclockDriver RCL_PPS_driver = { NULL, NULL, NULL }; + +#endif |