Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
[pandora-kernel.git] / 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 }