ptp: add the PTP_SYS_OFFSET ioctl to the testptp program

This patch add a method into testptp.c to measure the time offset
between phc and system clock through the ioctl PTP_SYS_OFFSET.

Signed-off-by: Dong Zhu <bluezhudong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/Documentation/ptp/testptp.c b/Documentation/ptp/testptp.c
index f59ded06610813f058d30ae468dbcf3922fc34b7..a74d0a84d329a2909186256d9ad5fdb5f5327a2e 100644 (file)
--- a/Documentation/ptp/testptp.c
+++ b/Documentation/ptp/testptp.c
@@ -100,6 +100,11 @@ static long ppb_to_scaled_ppm(int ppb)
        return (long) (ppb * 65.536);
 }
 
+static int64_t pctns(struct ptp_clock_time *t)
+{
+       return t->sec * 1000000000LL + t->nsec;
+}
+
 static void usage(char *progname)
 {
        fprintf(stderr,
@@ -112,6 +117,8 @@ static void usage(char *progname)
                " -f val     adjust the ptp clock frequency by 'val' ppb\n"
                " -g         get the ptp clock time\n"
                " -h         prints this message\n"
+               " -k val     measure the time offset between system and phc clock\n"
+               "            for 'val' times (Maximum 25)\n"
                " -p val     enable output with a period of 'val' nanoseconds\n"
                " -P val     enable or disable (val=1|0) the system clock PPS\n"
                " -s         set the ptp clock time from the system time\n"
@@ -133,8 +140,12 @@ int main(int argc, char *argv[])
        struct itimerspec timeout;
        struct sigevent sigevent;
 
+       struct ptp_clock_time *pct;
+       struct ptp_sys_offset *sysoff;
+
+
        char *progname;
-       int c, cnt, fd;
+       int i, c, cnt, fd;
 
        char *device = DEVICE;
        clockid_t clkid;
@@ -144,14 +155,19 @@ int main(int argc, char *argv[])
        int extts = 0;
        int gettime = 0;
        int oneshot = 0;
+       int pct_offset = 0;
+       int n_samples = 0;
        int periodic = 0;
        int perout = -1;
        int pps = -1;
        int settime = 0;
 
+       int64_t t1, t2, tp;
+       int64_t interval, offset;
+
        progname = strrchr(argv[0], '/');
        progname = progname ? 1+progname : argv[0];
-       while (EOF != (c = getopt(argc, argv, "a:A:cd:e:f:ghp:P:sSt:v"))) {
+       while (EOF != (c = getopt(argc, argv, "a:A:cd:e:f:ghk:p:P:sSt:v"))) {
                switch (c) {
                case 'a':
                        oneshot = atoi(optarg);
@@ -174,6 +190,10 @@ int main(int argc, char *argv[])
                case 'g':
                        gettime = 1;
                        break;
+               case 'k':
+                       pct_offset = 1;
+                       n_samples = atoi(optarg);
+                       break;
                case 'p':
                        perout = atoi(optarg);
                        break;
@@ -376,6 +396,47 @@ int main(int argc, char *argv[])
                }
        }
 
+       if (pct_offset) {
+               if (n_samples <= 0 || n_samples > 25) {
+                       puts("n_samples should be between 1 and 25");
+                       usage(progname);
+                       return -1;
+               }
+
+               sysoff = calloc(1, sizeof(*sysoff));
+               if (!sysoff) {
+                       perror("calloc");
+                       return -1;
+               }
+               sysoff->n_samples = n_samples;
+
+               if (ioctl(fd, PTP_SYS_OFFSET, sysoff))
+                       perror("PTP_SYS_OFFSET");
+               else
+                       puts("system and phc clock time offset request okay");
+
+               pct = &sysoff->ts[0];
+               for (i = 0; i < sysoff->n_samples; i++) {
+                       t1 = pctns(pct+2*i);
+                       tp = pctns(pct+2*i+1);
+                       t2 = pctns(pct+2*i+2);
+                       interval = t2 - t1;
+                       offset = (t2 + t1) / 2 - tp;
+
+                       printf("system time: %ld.%ld\n",
+                               (pct+2*i)->sec, (pct+2*i)->nsec);
+                       printf("phc    time: %ld.%ld\n",
+                               (pct+2*i+1)->sec, (pct+2*i+1)->nsec);
+                       printf("system time: %ld.%ld\n",
+                               (pct+2*i+2)->sec, (pct+2*i+2)->nsec);
+                       printf("system/phc clock time offset is %ld ns\n"
+                               "system     clock time delay  is %ld ns\n",
+                               offset, interval);
+               }
+
+               free(sysoff);
+       }
+
        close(fd);
        return 0;
 }