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