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Based on kernel version 3.9. Page generated on 2013-05-02 23:12 EST.

	/*
	 * PTP 1588 clock support - User space test program
	 *
	 * Copyright (C) 2010 OMICRON electronics GmbH
	 *
	 *  This program is free software; you can redistribute it and/or modify
	 *  it under the terms of the GNU General Public License as published by
	 *  the Free Software Foundation; either version 2 of the License, or
	 *  (at your option) any later version.
	 *
	 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
	 */
	#include <errno.h>
	#include <fcntl.h>
	#include <math.h>
	#include <signal.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/ioctl.h>
	#include <sys/mman.h>
	#include <sys/stat.h>
	#include <sys/time.h>
	#include <sys/timex.h>
	#include <sys/types.h>
	#include <time.h>
	#include <unistd.h>
	
	#include <linux/ptp_clock.h>
	
	#define DEVICE "/dev/ptp0"
	
	#ifndef ADJ_SETOFFSET
	#define ADJ_SETOFFSET 0x0100
	#endif
	
	#ifndef CLOCK_INVALID
	#define CLOCK_INVALID -1
	#endif
	
	/* When glibc offers the syscall, this will go away. */
	#include <sys/syscall.h>
	static int clock_adjtime(clockid_t id, struct timex *tx)
	{
		return syscall(__NR_clock_adjtime, id, tx);
	}
	
	static clockid_t get_clockid(int fd)
	{
	#define CLOCKFD 3
	#define FD_TO_CLOCKID(fd)	((~(clockid_t) (fd) << 3) | CLOCKFD)
	
		return FD_TO_CLOCKID(fd);
	}
	
	static void handle_alarm(int s)
	{
		printf("received signal %d\n", s);
	}
	
	static int install_handler(int signum, void (*handler)(int))
	{
		struct sigaction action;
		sigset_t mask;
	
		/* Unblock the signal. */
		sigemptyset(&mask);
		sigaddset(&mask, signum);
		sigprocmask(SIG_UNBLOCK, &mask, NULL);
	
		/* Install the signal handler. */
		action.sa_handler = handler;
		action.sa_flags = 0;
		sigemptyset(&action.sa_mask);
		sigaction(signum, &action, NULL);
	
		return 0;
	}
	
	static long ppb_to_scaled_ppm(int ppb)
	{
		/*
		 * The 'freq' field in the 'struct timex' is in parts per
		 * million, but with a 16 bit binary fractional field.
		 * Instead of calculating either one of
		 *
		 *    scaled_ppm = (ppb / 1000) << 16  [1]
		 *    scaled_ppm = (ppb << 16) / 1000  [2]
		 *
		 * we simply use double precision math, in order to avoid the
		 * truncation in [1] and the possible overflow in [2].
		 */
		return (long) (ppb * 65.536);
	}
	
	static void usage(char *progname)
	{
		fprintf(stderr,
			"usage: %s [options]\n"
			" -a val     request a one-shot alarm after 'val' seconds\n"
			" -A val     request a periodic alarm every 'val' seconds\n"
			" -c         query the ptp clock's capabilities\n"
			" -d name    device to open\n"
			" -e val     read 'val' external time stamp events\n"
			" -f val     adjust the ptp clock frequency by 'val' ppb\n"
			" -g         get the ptp clock time\n"
			" -h         prints this message\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"
			" -S         set the system time from the ptp clock time\n"
			" -t val     shift the ptp clock time by 'val' seconds\n",
			progname);
	}
	
	int main(int argc, char *argv[])
	{
		struct ptp_clock_caps caps;
		struct ptp_extts_event event;
		struct ptp_extts_request extts_request;
		struct ptp_perout_request perout_request;
		struct timespec ts;
		struct timex tx;
	
		static timer_t timerid;
		struct itimerspec timeout;
		struct sigevent sigevent;
	
		char *progname;
		int c, cnt, fd;
	
		char *device = DEVICE;
		clockid_t clkid;
		int adjfreq = 0x7fffffff;
		int adjtime = 0;
		int capabilities = 0;
		int extts = 0;
		int gettime = 0;
		int oneshot = 0;
		int periodic = 0;
		int perout = -1;
		int pps = -1;
		int settime = 0;
	
		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"))) {
			switch (c) {
			case 'a':
				oneshot = atoi(optarg);
				break;
			case 'A':
				periodic = atoi(optarg);
				break;
			case 'c':
				capabilities = 1;
				break;
			case 'd':
				device = optarg;
				break;
			case 'e':
				extts = atoi(optarg);
				break;
			case 'f':
				adjfreq = atoi(optarg);
				break;
			case 'g':
				gettime = 1;
				break;
			case 'p':
				perout = atoi(optarg);
				break;
			case 'P':
				pps = atoi(optarg);
				break;
			case 's':
				settime = 1;
				break;
			case 'S':
				settime = 2;
				break;
			case 't':
				adjtime = atoi(optarg);
				break;
			case 'h':
				usage(progname);
				return 0;
			case '?':
			default:
				usage(progname);
				return -1;
			}
		}
	
		fd = open(device, O_RDWR);
		if (fd < 0) {
			fprintf(stderr, "opening %s: %s\n", device, strerror(errno));
			return -1;
		}
	
		clkid = get_clockid(fd);
		if (CLOCK_INVALID == clkid) {
			fprintf(stderr, "failed to read clock id\n");
			return -1;
		}
	
		if (capabilities) {
			if (ioctl(fd, PTP_CLOCK_GETCAPS, &caps)) {
				perror("PTP_CLOCK_GETCAPS");
			} else {
				printf("capabilities:\n"
				       "  %d maximum frequency adjustment (ppb)\n"
				       "  %d programmable alarms\n"
				       "  %d external time stamp channels\n"
				       "  %d programmable periodic signals\n"
				       "  %d pulse per second\n",
				       caps.max_adj,
				       caps.n_alarm,
				       caps.n_ext_ts,
				       caps.n_per_out,
				       caps.pps);
			}
		}
	
		if (0x7fffffff != adjfreq) {
			memset(&tx, 0, sizeof(tx));
			tx.modes = ADJ_FREQUENCY;
			tx.freq = ppb_to_scaled_ppm(adjfreq);
			if (clock_adjtime(clkid, &tx)) {
				perror("clock_adjtime");
			} else {
				puts("frequency adjustment okay");
			}
		}
	
		if (adjtime) {
			memset(&tx, 0, sizeof(tx));
			tx.modes = ADJ_SETOFFSET;
			tx.time.tv_sec = adjtime;
			tx.time.tv_usec = 0;
			if (clock_adjtime(clkid, &tx) < 0) {
				perror("clock_adjtime");
			} else {
				puts("time shift okay");
			}
		}
	
		if (gettime) {
			if (clock_gettime(clkid, &ts)) {
				perror("clock_gettime");
			} else {
				printf("clock time: %ld.%09ld or %s",
				       ts.tv_sec, ts.tv_nsec, ctime(&ts.tv_sec));
			}
		}
	
		if (settime == 1) {
			clock_gettime(CLOCK_REALTIME, &ts);
			if (clock_settime(clkid, &ts)) {
				perror("clock_settime");
			} else {
				puts("set time okay");
			}
		}
	
		if (settime == 2) {
			clock_gettime(clkid, &ts);
			if (clock_settime(CLOCK_REALTIME, &ts)) {
				perror("clock_settime");
			} else {
				puts("set time okay");
			}
		}
	
		if (extts) {
			memset(&extts_request, 0, sizeof(extts_request));
			extts_request.index = 0;
			extts_request.flags = PTP_ENABLE_FEATURE;
			if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) {
				perror("PTP_EXTTS_REQUEST");
				extts = 0;
			} else {
				puts("external time stamp request okay");
			}
			for (; extts; extts--) {
				cnt = read(fd, &event, sizeof(event));
				if (cnt != sizeof(event)) {
					perror("read");
					break;
				}
				printf("event index %u at %lld.%09u\n", event.index,
				       event.t.sec, event.t.nsec);
				fflush(stdout);
			}
			/* Disable the feature again. */
			extts_request.flags = 0;
			if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) {
				perror("PTP_EXTTS_REQUEST");
			}
		}
	
		if (oneshot) {
			install_handler(SIGALRM, handle_alarm);
			/* Create a timer. */
			sigevent.sigev_notify = SIGEV_SIGNAL;
			sigevent.sigev_signo = SIGALRM;
			if (timer_create(clkid, &sigevent, &timerid)) {
				perror("timer_create");
				return -1;
			}
			/* Start the timer. */
			memset(&timeout, 0, sizeof(timeout));
			timeout.it_value.tv_sec = oneshot;
			if (timer_settime(timerid, 0, &timeout, NULL)) {
				perror("timer_settime");
				return -1;
			}
			pause();
			timer_delete(timerid);
		}
	
		if (periodic) {
			install_handler(SIGALRM, handle_alarm);
			/* Create a timer. */
			sigevent.sigev_notify = SIGEV_SIGNAL;
			sigevent.sigev_signo = SIGALRM;
			if (timer_create(clkid, &sigevent, &timerid)) {
				perror("timer_create");
				return -1;
			}
			/* Start the timer. */
			memset(&timeout, 0, sizeof(timeout));
			timeout.it_interval.tv_sec = periodic;
			timeout.it_value.tv_sec = periodic;
			if (timer_settime(timerid, 0, &timeout, NULL)) {
				perror("timer_settime");
				return -1;
			}
			while (1) {
				pause();
			}
			timer_delete(timerid);
		}
	
		if (perout >= 0) {
			if (clock_gettime(clkid, &ts)) {
				perror("clock_gettime");
				return -1;
			}
			memset(&perout_request, 0, sizeof(perout_request));
			perout_request.index = 0;
			perout_request.start.sec = ts.tv_sec + 2;
			perout_request.start.nsec = 0;
			perout_request.period.sec = 0;
			perout_request.period.nsec = perout;
			if (ioctl(fd, PTP_PEROUT_REQUEST, &perout_request)) {
				perror("PTP_PEROUT_REQUEST");
			} else {
				puts("periodic output request okay");
			}
		}
	
		if (pps != -1) {
			int enable = pps ? 1 : 0;
			if (ioctl(fd, PTP_ENABLE_PPS, enable)) {
				perror("PTP_ENABLE_PPS");
			} else {
				puts("pps for system time request okay");
			}
		}
	
		close(fd);
		return 0;
	}

• [ ptp ]
• ptp.txt
• testptp.c
• testptp.mk
•