Here some utilities and examples about the PPS API and the LinuxPPS
support.
* ppstest.c implements an useful testing program, while
* ppsfind tries to help the user into finding a specific PPS source by
using its name or path.
Signed-off-by: Rodolfo Giometti <giometti@linux.it>
---
Documentation/pps/Makefile | 27 ++++++++
Documentation/pps/ppsfind | 17 +++++
Documentation/pps/ppstest.c | 151 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 195 insertions(+), 0 deletions(-)
create mode 100644 Documentation/pps/Makefile
create mode 100644 Documentation/pps/ppsfind
create mode 100644 Documentation/pps/ppstest.c
diff --git a/Documentation/pps/Makefile b/Documentation/pps/Makefile
new file mode 100644
index 0000000..af4f9b4
--- /dev/null
+++ b/Documentation/pps/Makefile
@@ -0,0 +1,27 @@
+TARGETS = ppstest
+
+CFLAGS += -Wall -O2 -D_GNU_SOURCE
+CFLAGS += -I .
+CFLAGS += -ggdb
+
+# -- Actions section --
+
+.PHONY : all depend dep
+
+all : .depend $(TARGETS)
+
+.depend depend dep :
+ $(CC) $(CFLAGS) -M $(TARGETS:=.c) > .depend
+
+ifeq (.depend,$(wildcard .depend))
+include .depend
+endif
+
+
+# -- Clean section --
+
+.PHONY : clean
+
+clean :
+ rm -f *.o *~ core .depend
+ rm -f ${TARGETS}
diff --git a/Documentation/pps/ppsfind b/Documentation/pps/ppsfind
new file mode 100644
index 0000000..93c0e17
--- /dev/null
+++ b/Documentation/pps/ppsfind
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+SYS="/sys/class/pps/"
+
+if [ $# -lt 1 ] ; then
+ echo "usage: ppsfind <name>" >&2
+ exit 1
+fi
+
+for d in $(ls $SYS) ; do
+ if grep $1 $SYS/$d/name >& /dev/null || \
+ grep $1 $SYS/$d/path >& /dev/null ; then
+ echo "$d: name=$(cat $SYS/$d/name) path=$(cat $SYS/$d/path)"
+ fi
+done
+
+exit 0
diff --git a/Documentation/pps/ppstest.c b/Documentation/pps/ppstest.c
new file mode 100644
index 0000000..d125ffa
--- /dev/null
+++ b/Documentation/pps/ppstest.c
@@ -0,0 +1,151 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include <timepps.h>
+
+int find_source(char *path, pps_handle_t *handle, int *avail_mode)
+{
+ pps_params_t params;
+ int ret;
+
+ printf("trying PPS source \"%s\"\n", path);
+
+ /* Try to find the source by using the supplied "path" name */
+ ret = open(path, O_RDWR);
+ if (ret < 0) {
+ fprintf(stderr, "unable to open device \"%s\" (%m)\n", path);
+ return ret;
+ }
+
+ /* Open the PPS source (and check the file descriptor) */
+ ret = time_pps_create(ret, handle);
+ if (ret < 0) {
+ fprintf(stderr, "cannot create a PPS source from device "
+ "\"%s\" (%m)\n", path);
+ return -1;
+ }
+ printf("found PPS source \"%s\"\n", path);
+
+ /* Find out what features are supported */
+ ret = time_pps_getcap(*handle, avail_mode);
+ if (ret < 0) {
+ fprintf(stderr, "cannot get capabilities (%m)\n");
+ return -1;
+ }
+ if ((*avail_mode & PPS_CAPTUREASSERT) == 0) {
+ fprintf(stderr, "cannot CAPTUREASSERT\n");
+ return -1;
+ }
+ if ((*avail_mode & PPS_OFFSETASSERT) == 0) {
+ fprintf(stderr, "cannot OFFSETASSERT\n");
+ return -1;
+ }
+
+ /* Capture assert timestamps, and compensate for a 675 nsec
+ * propagation delay */
+ ret = time_pps_getparams(*handle, ¶ms);
+ if (ret < 0) {
+ fprintf(stderr, "cannot get parameters (%m)\n");
+ return -1;
+ }
+ params.assert_offset.tv_sec = 0;
+ params.assert_offset.tv_nsec = 675;
+ params.mode |= PPS_CAPTUREASSERT | PPS_OFFSETASSERT;
+ ret = time_pps_setparams(*handle, ¶ms);
+ if (ret < 0) {
+ fprintf(stderr, "cannot set parameters (%m)\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+int fetch_source(int i, pps_handle_t *handle, int *avail_mode)
+{
+ struct timespec timeout;
+ pps_info_t infobuf;
+ int ret;
+
+ /* create a zero-valued timeout */
+ timeout.tv_sec = 3;
+ timeout.tv_nsec = 0;
+
+retry:
+ if (*avail_mode & PPS_CANWAIT) /* waits for the next event */
+ ret = time_pps_fetch(*handle, PPS_TSFMT_TSPEC, &infobuf,
+ &timeout);
+ else {
+ sleep(1);
+ ret = time_pps_fetch(*handle, PPS_TSFMT_TSPEC, &infobuf,
+ &timeout);
+ }
+ if (ret < 0) {
+ if (ret == -EINTR) {
+ fprintf(stderr, "time_pps_fetch() got a signal!\n");
+ goto retry;
+ }
+
+ fprintf(stderr, "time_pps_fetch() error %d (%m)\n", ret);
+ return -1;
+ }
+
+ printf("source %d - "
+ "assert %ld.%09ld, sequence: %ld - "
+ "clear %ld.%09ld, sequence: %ld\n",
+ i,
+ infobuf.assert_timestamp.tv_sec,
+ infobuf.assert_timestamp.tv_nsec,
+ infobuf.assert_sequence,
+ infobuf.clear_timestamp.tv_sec,
+ infobuf.clear_timestamp.tv_nsec, infobuf.clear_sequence);
+
+ return 0;
+}
+
+void usage(char *name)
+{
+ fprintf(stderr, "usage: %s <ppsdev> [<ppsdev> ...]\n", name);
+ exit(EXIT_FAILURE);
+}
+
+int main(int argc, char *argv[])
+{
+ int num;
+ pps_handle_t handle[4];
+ int avail_mode[4];
+ int i = 0;
+ int ret;
+
+ /* Check the command line */
+ if (argc < 2)
+ usage(argv[0]);
+
+ for (i = 1; i < argc && i <= 4; i++) {
+ ret = find_source(argv[i], &handle[i - 1], &avail_mode[i - 1]);
+ if (ret < 0)
+ exit(EXIT_FAILURE);
+ }
+
+ num = i - 1;
+ printf("ok, found %d source(s), now start fetching data...\n", num);
+
+ /* loop, printing the most recent timestamp every second or so */
+ while (1) {
+ for (i = 0; i < num; i++) {
+ ret = fetch_source(i, &handle[i], &avail_mode[i]);
+ if (ret < 0 && errno != ETIMEDOUT)
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ for (; i >= 0; i--)
+ time_pps_destroy(handle[i]);
+
+ return 0;
+}
--
1.5.2.5
--
