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-rw-r--r--refclock_pps.c159
1 files changed, 159 insertions, 0 deletions
diff --git a/refclock_pps.c b/refclock_pps.c
new file mode 100644
index 0000000..880c13f
--- /dev/null
+++ b/refclock_pps.c
@@ -0,0 +1,159 @@
+/*
+ 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) {
+ const char *options[] = {"clear", NULL};
+ pps_handle_t handle;
+ pps_params_t params;
+ struct pps_instance *pps;
+ int fd, edge_clear, mode;
+ char *path;
+
+ RCL_CheckDriverOptions(instance, options);
+
+ 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));
+
+ UTI_FdSetCloexec(fd);
+
+ if (time_pps_create(fd, &handle) < 0)
+ LOG_FATAL("time_pps_create() failed on %s : %s", path, strerror(errno));
+
+ if (time_pps_getcap(handle, &mode) < 0)
+ LOG_FATAL("time_pps_getcap() failed on %s : %s", path, strerror(errno));
+
+ if (time_pps_getparams(handle, &params) < 0)
+ LOG_FATAL("time_pps_getparams() failed on %s : %s", path, strerror(errno));
+
+ if (!edge_clear) {
+ if (!(mode & PPS_CAPTUREASSERT))
+ LOG_FATAL("CAPTUREASSERT not supported on %s", path);
+
+ params.mode |= PPS_CAPTUREASSERT;
+ params.mode &= ~PPS_CAPTURECLEAR;
+ } else {
+ if (!(mode & PPS_CAPTURECLEAR))
+ LOG_FATAL("CAPTURECLEAR not supported on %s", path);
+
+ params.mode |= PPS_CAPTURECLEAR;
+ params.mode &= ~PPS_CAPTUREASSERT;
+ }
+
+ if (time_pps_setparams(handle, &params) < 0)
+ LOG_FATAL("time_pps_setparams() failed on %s : %s", path, strerror(errno));
+
+ 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