Documentation/ptp/testptp.c

   1 /*
   2  * PTP 1588 clock support - User space test program
   3  *
   4  * Copyright (C) 2010 OMICRON electronics GmbH
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  */
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <math.h>
  23 #include <signal.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <sys/ioctl.h>
  28 #include <sys/mman.h>
  29 #include <sys/stat.h>
  30 #include <sys/time.h>
  31 #include <sys/timex.h>
  32 #include <sys/types.h>
  33 #include <time.h>
  34 #include <unistd.h>
  35
  36 #include <linux/ptp_clock.h>
  37
  38 #define DEVICE "/dev/ptp0"
  39
  40 #ifndef ADJ_SETOFFSET
  41 #define ADJ_SETOFFSET 0x0100
  42 #endif
  43
  44 #ifndef CLOCK_INVALID
  45 #define CLOCK_INVALID -1
  46 #endif
  47
  48 /* When glibc offers the syscall, this will go away. */
  49 #include <sys/syscall.h>
  50 static int clock_adjtime(clockid_t id, struct timex *tx)
  51 {
  52         return syscall(__NR_clock_adjtime, id, tx);
  53 }
  54
  55 static clockid_t get_clockid(int fd)
  56 {
  57 #define CLOCKFD 3
  58 #define FD_TO_CLOCKID(fd)       ((~(clockid_t) (fd) << 3) | CLOCKFD)
  59
  60         return FD_TO_CLOCKID(fd);
  61 }
  62
  63 static void handle_alarm(int s)
  64 {
  65         printf("received signal %d\n", s);
  66 }
  67
  68 static int install_handler(int signum, void (*handler)(int))
  69 {
  70         struct sigaction action;
  71         sigset_t mask;
  72
  73         /* Unblock the signal. */
  74         sigemptyset(&mask);
  75         sigaddset(&mask, signum);
  76         sigprocmask(SIG_UNBLOCK, &mask, NULL);
  77
  78         /* Install the signal handler. */
  79         action.sa_handler = handler;
  80         action.sa_flags = 0;
  81         sigemptyset(&action.sa_mask);
  82         sigaction(signum, &action, NULL);
  83
  84         return 0;
  85 }
  86
  87 static long ppb_to_scaled_ppm(int ppb)
  88 {
  89         /*
  90          * The 'freq' field in the 'struct timex' is in parts per
  91          * million, but with a 16 bit binary fractional field.
  92          * Instead of calculating either one of
  93          *
  94          *    scaled_ppm = (ppb / 1000) << 16  [1]
  95          *    scaled_ppm = (ppb << 16) / 1000  [2]
  96          *
  97          * we simply use double precision math, in order to avoid the
  98          * truncation in [1] and the possible overflow in [2].
  99          */
 100         return (long) (ppb * 65.536);
 101 }
 102
 103 static void usage(char *progname)
 104 {
 105         fprintf(stderr,
 106                 "usage: %s [options]\n"
 107                 " -a val     request a one-shot alarm after 'val' seconds\n"
 108                 " -A val     request a periodic alarm every 'val' seconds\n"
 109                 " -c         query the ptp clock's capabilities\n"
 110                 " -d name    device to open\n"
 111                 " -e val     read 'val' external time stamp events\n"
 112                 " -f val     adjust the ptp clock frequency by 'val' ppb\n"
 113                 " -g         get the ptp clock time\n"
 114                 " -h         prints this message\n"
 115                 " -p val     enable output with a period of 'val' nanoseconds\n"
 116                 " -P val     enable or disable (val=1|0) the system clock PPS\n"
 117                 " -s         set the ptp clock time from the system time\n"
 118                 " -S         set the system time from the ptp clock time\n"
 119                 " -t val     shift the ptp clock time by 'val' seconds\n",
 120                 progname);
 121 }
 122
 123 int main(int argc, char *argv[])
 124 {
 125         struct ptp_clock_caps caps;
 126         struct ptp_extts_event event;
 127         struct ptp_extts_request extts_request;
 128         struct ptp_perout_request perout_request;
 129         struct timespec ts;
 130         struct timex tx;
 131
 132         static timer_t timerid;
 133         struct itimerspec timeout;
 134         struct sigevent sigevent;
 135
 136         char *progname;
 137         int c, cnt, fd;
 138
 139         char *device = DEVICE;
 140         clockid_t clkid;
 141         int adjfreq = 0x7fffffff;
 142         int adjtime = 0;
 143         int capabilities = 0;
 144         int extts = 0;
 145         int gettime = 0;
 146         int oneshot = 0;
 147         int periodic = 0;
 148         int perout = -1;
 149         int pps = -1;
 150         int settime = 0;
 151
 152         progname = strrchr(argv[0], '/');
 153         progname = progname ? 1+progname : argv[0];
 154         while (EOF != (c = getopt(argc, argv, "a:A:cd:e:f:ghp:P:sSt:v"))) {
 155                 switch (c) {
 156                 case 'a':
 157                         oneshot = atoi(optarg);
 158                         break;
 159                 case 'A':
 160                         periodic = atoi(optarg);
 161                         break;
 162                 case 'c':
 163                         capabilities = 1;
 164                         break;
 165                 case 'd':
 166                         device = optarg;
 167                         break;
 168                 case 'e':
 169                         extts = atoi(optarg);
 170                         break;
 171                 case 'f':
 172                         adjfreq = atoi(optarg);
 173                         break;
 174                 case 'g':
 175                         gettime = 1;
 176                         break;
 177                 case 'p':
 178                         perout = atoi(optarg);
 179                         break;
 180                 case 'P':
 181                         pps = atoi(optarg);
 182                         break;
 183                 case 's':
 184                         settime = 1;
 185                         break;
 186                 case 'S':
 187                         settime = 2;
 188                         break;
 189                 case 't':
 190                         adjtime = atoi(optarg);
 191                         break;
 192                 case 'h':
 193                         usage(progname);
 194                         return 0;
 195                 case '?':
 196                 default:
 197                         usage(progname);
 198                         return -1;
 199                 }
 200         }
 201
 202         fd = open(device, O_RDWR);
 203         if (fd < 0) {
 204                 fprintf(stderr, "opening %s: %s\n", device, strerror(errno));
 205                 return -1;
 206         }
 207
 208         clkid = get_clockid(fd);
 209         if (CLOCK_INVALID == clkid) {
 210                 fprintf(stderr, "failed to read clock id\n");
 211                 return -1;
 212         }
 213
 214         if (capabilities) {
 215                 if (ioctl(fd, PTP_CLOCK_GETCAPS, &caps)) {
 216                         perror("PTP_CLOCK_GETCAPS");
 217                 } else {
 218                         printf("capabilities:\n"
 219                                "  %d maximum frequency adjustment (ppb)\n"
 220                                "  %d programmable alarms\n"
 221                                "  %d external time stamp channels\n"
 222                                "  %d programmable periodic signals\n"
 223                                "  %d pulse per second\n",
 224                                caps.max_adj,
 225                                caps.n_alarm,
 226                                caps.n_ext_ts,
 227                                caps.n_per_out,
 228                                caps.pps);
 229                 }
 230         }
 231
 232         if (0x7fffffff != adjfreq) {
 233                 memset(&tx, 0, sizeof(tx));
 234                 tx.modes = ADJ_FREQUENCY;
 235                 tx.freq = ppb_to_scaled_ppm(adjfreq);
 236                 if (clock_adjtime(clkid, &tx)) {
 237                         perror("clock_adjtime");
 238                 } else {
 239                         puts("frequency adjustment okay");
 240                 }
 241         }
 242
 243         if (adjtime) {
 244                 memset(&tx, 0, sizeof(tx));
 245                 tx.modes = ADJ_SETOFFSET;
 246                 tx.time.tv_sec = adjtime;
 247                 tx.time.tv_usec = 0;
 248                 if (clock_adjtime(clkid, &tx) < 0) {
 249                         perror("clock_adjtime");
 250                 } else {
 251                         puts("time shift okay");
 252                 }
 253         }
 254
 255         if (gettime) {
 256                 if (clock_gettime(clkid, &ts)) {
 257                         perror("clock_gettime");
 258                 } else {
 259                         printf("clock time: %ld.%09ld or %s",
 260                                ts.tv_sec, ts.tv_nsec, ctime(&ts.tv_sec));
 261                 }
 262         }
 263
 264         if (settime == 1) {
 265                 clock_gettime(CLOCK_REALTIME, &ts);
 266                 if (clock_settime(clkid, &ts)) {
 267                         perror("clock_settime");
 268                 } else {
 269                         puts("set time okay");
 270                 }
 271         }
 272
 273         if (settime == 2) {
 274                 clock_gettime(clkid, &ts);
 275                 if (clock_settime(CLOCK_REALTIME, &ts)) {
 276                         perror("clock_settime");
 277                 } else {
 278                         puts("set time okay");
 279                 }
 280         }
 281
 282         if (extts) {
 283                 memset(&extts_request, 0, sizeof(extts_request));
 284                 extts_request.index = 0;
 285                 extts_request.flags = PTP_ENABLE_FEATURE;
 286                 if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) {
 287                         perror("PTP_EXTTS_REQUEST");
 288                         extts = 0;
 289                 } else {
 290                         puts("external time stamp request okay");
 291                 }
 292                 for (; extts; extts--) {
 293                         cnt = read(fd, &event, sizeof(event));
 294                         if (cnt != sizeof(event)) {
 295                                 perror("read");
 296                                 break;
 297                         }
 298                         printf("event index %u at %lld.%09u\n", event.index,
 299                                event.t.sec, event.t.nsec);
 300                         fflush(stdout);
 301                 }
 302                 /* Disable the feature again. */
 303                 extts_request.flags = 0;
 304                 if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) {
 305                         perror("PTP_EXTTS_REQUEST");
 306                 }
 307         }
 308
 309         if (oneshot) {
 310                 install_handler(SIGALRM, handle_alarm);
 311                 /* Create a timer. */
 312                 sigevent.sigev_notify = SIGEV_SIGNAL;
 313                 sigevent.sigev_signo = SIGALRM;
 314                 if (timer_create(clkid, &sigevent, &timerid)) {
 315                         perror("timer_create");
 316                         return -1;
 317                 }
 318                 /* Start the timer. */
 319                 memset(&timeout, 0, sizeof(timeout));
 320                 timeout.it_value.tv_sec = oneshot;
 321                 if (timer_settime(timerid, 0, &timeout, NULL)) {
 322                         perror("timer_settime");
 323                         return -1;
 324                 }
 325                 pause();
 326                 timer_delete(timerid);
 327         }
 328
 329         if (periodic) {
 330                 install_handler(SIGALRM, handle_alarm);
 331                 /* Create a timer. */
 332                 sigevent.sigev_notify = SIGEV_SIGNAL;
 333                 sigevent.sigev_signo = SIGALRM;
 334                 if (timer_create(clkid, &sigevent, &timerid)) {
 335                         perror("timer_create");
 336                         return -1;
 337                 }
 338                 /* Start the timer. */
 339                 memset(&timeout, 0, sizeof(timeout));
 340                 timeout.it_interval.tv_sec = periodic;
 341                 timeout.it_value.tv_sec = periodic;
 342                 if (timer_settime(timerid, 0, &timeout, NULL)) {
 343                         perror("timer_settime");
 344                         return -1;
 345                 }
 346                 while (1) {
 347                         pause();
 348                 }
 349                 timer_delete(timerid);
 350         }
 351
 352         if (perout >= 0) {
 353                 if (clock_gettime(clkid, &ts)) {
 354                         perror("clock_gettime");
 355                         return -1;
 356                 }
 357                 memset(&perout_request, 0, sizeof(perout_request));
 358                 perout_request.index = 0;
 359                 perout_request.start.sec = ts.tv_sec + 2;
 360                 perout_request.start.nsec = 0;
 361                 perout_request.period.sec = 0;
 362                 perout_request.period.nsec = perout;
 363                 if (ioctl(fd, PTP_PEROUT_REQUEST, &perout_request)) {
 364                         perror("PTP_PEROUT_REQUEST");
 365                 } else {
 366                         puts("periodic output request okay");
 367                 }
 368         }
 369
 370         if (pps != -1) {
 371                 int enable = pps ? 1 : 0;
 372                 if (ioctl(fd, PTP_ENABLE_PPS, enable)) {
 373                         perror("PTP_ENABLE_PPS");
 374                 } else {
 375                         puts("pps for system time request okay");
 376                 }
 377         }
 378
 379         close(fd);
 380         return 0;
 381 }