linux/Documentation/ptp/testptp.c
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   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>
  50static int clock_adjtime(clockid_t id, struct timex *tx)
  51{
  52        return syscall(__NR_clock_adjtime, id, tx);
  53}
  54
  55static 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
  63static void handle_alarm(int s)
  64{
  65        printf("received signal %d\n", s);
  66}
  67
  68static 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
  87static 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
 103static 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
 123int 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}
 382
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