kernel-ark/Documentation/ptp/testptp.c
Richard Cochran d94ba80ebb ptp: Added a brand new class driver for ptp clocks.
This patch adds an infrastructure for hardware clocks that implement
IEEE 1588, the Precision Time Protocol (PTP). A class driver offers a
registration method to particular hardware clock drivers. Each clock is
presented as a standard POSIX clock.

The ancillary clock features are exposed in two different ways, via
the sysfs and by a character device.

Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-05-23 13:01:00 -07:00

382 lines
8.7 KiB
C

/*
* 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;
}