1 /*
2 * Real Time Clock Driver Test/Example Program
3 *
4 * Compile with:
5 * gcc -s -Wall -Wstrict-prototypes rtctest.c -o rtctest
6 *
7 * Copyright (C) 1996, Paul Gortmaker.
8 *
9 * Released under the GNU General Public License, version 2,
10 * included herein by reference.
11 *
12 */
13
14 #include <stdio.h>
15 #include <linux/rtc.h>
16 #include <sys/ioctl.h>
17 #include <sys/time.h>
18 #include <sys/types.h>
19 #include <fcntl.h>
20 #include <unistd.h>
21 #include <stdlib.h>
22 #include <errno.h>
23
24 #ifndef ARRAY_SIZE
25 # define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
26 #endif
27
28 /*
29 * This expects the new RTC class driver framework, working with
30 * clocks that will often not be clones of what the PC-AT had.
31 * Use the command line to specify another RTC if you need one.
32 */
33 static const char default_rtc[] = "/dev/rtc0";
34
35 static struct rtc_time cutoff_dates[] = {
36 {
37 .tm_year = 70, /* 1970 -1900 */
38 .tm_mday = 1,
39 },
40 /* signed time_t 19/01/2038 3:14:08 */
41 {
42 .tm_year = 138,
43 .tm_mday = 19,
44 },
45 {
46 .tm_year = 138,
47 .tm_mday = 20,
48 },
49 {
50 .tm_year = 199, /* 2099 -1900 */
51 .tm_mday = 1,
52 },
53 {
54 .tm_year = 200, /* 2100 -1900 */
55 .tm_mday = 1,
56 },
57 /* unsigned time_t 07/02/2106 7:28:15*/
58 {
59 .tm_year = 205,
60 .tm_mon = 1,
61 .tm_mday = 7,
62 },
63 {
64 .tm_year = 206,
65 .tm_mon = 1,
66 .tm_mday = 8,
67 },
68 /* signed time on 64bit in nanoseconds 12/04/2262 01:47:16*/
69 {
70 .tm_year = 362,
71 .tm_mon = 3,
72 .tm_mday = 12,
73 },
74 {
75 .tm_year = 362, /* 2262 -1900 */
76 .tm_mon = 3,
77 .tm_mday = 13,
78 },
79 };
80
compare_dates(struct rtc_time * a,struct rtc_time * b)81 static int compare_dates(struct rtc_time *a, struct rtc_time *b)
82 {
83 if (a->tm_year != b->tm_year ||
84 a->tm_mon != b->tm_mon ||
85 a->tm_mday != b->tm_mday ||
86 a->tm_hour != b->tm_hour ||
87 a->tm_min != b->tm_min ||
88 ((b->tm_sec - a->tm_sec) > 1))
89 return 1;
90
91 return 0;
92 }
93
main(int argc,char ** argv)94 int main(int argc, char **argv)
95 {
96 int i, fd, retval, irqcount = 0, dangerous = 0;
97 unsigned long tmp, data;
98 struct rtc_time rtc_tm;
99 const char *rtc = default_rtc;
100 struct timeval start, end, diff;
101
102 switch (argc) {
103 case 3:
104 if (*argv[2] == 'd')
105 dangerous = 1;
106 case 2:
107 rtc = argv[1];
108 /* FALLTHROUGH */
109 case 1:
110 break;
111 default:
112 fprintf(stderr, "usage: rtctest [rtcdev] [d]\n");
113 return 1;
114 }
115
116 fd = open(rtc, O_RDONLY);
117
118 if (fd == -1) {
119 perror(rtc);
120 exit(errno);
121 }
122
123 fprintf(stderr, "\n\t\t\tRTC Driver Test Example.\n\n");
124
125 /* Turn on update interrupts (one per second) */
126 retval = ioctl(fd, RTC_UIE_ON, 0);
127 if (retval == -1) {
128 if (errno == EINVAL) {
129 fprintf(stderr,
130 "\n...Update IRQs not supported.\n");
131 goto test_READ;
132 }
133 perror("RTC_UIE_ON ioctl");
134 exit(errno);
135 }
136
137 fprintf(stderr, "Counting 5 update (1/sec) interrupts from reading %s:",
138 rtc);
139 fflush(stderr);
140 for (i=1; i<6; i++) {
141 /* This read will block */
142 retval = read(fd, &data, sizeof(unsigned long));
143 if (retval == -1) {
144 perror("read");
145 exit(errno);
146 }
147 fprintf(stderr, " %d",i);
148 fflush(stderr);
149 irqcount++;
150 }
151
152 fprintf(stderr, "\nAgain, from using select(2) on /dev/rtc:");
153 fflush(stderr);
154 for (i=1; i<6; i++) {
155 struct timeval tv = {5, 0}; /* 5 second timeout on select */
156 fd_set readfds;
157
158 FD_ZERO(&readfds);
159 FD_SET(fd, &readfds);
160 /* The select will wait until an RTC interrupt happens. */
161 retval = select(fd+1, &readfds, NULL, NULL, &tv);
162 if (retval == -1) {
163 perror("select");
164 exit(errno);
165 }
166 /* This read won't block unlike the select-less case above. */
167 retval = read(fd, &data, sizeof(unsigned long));
168 if (retval == -1) {
169 perror("read");
170 exit(errno);
171 }
172 fprintf(stderr, " %d",i);
173 fflush(stderr);
174 irqcount++;
175 }
176
177 /* Turn off update interrupts */
178 retval = ioctl(fd, RTC_UIE_OFF, 0);
179 if (retval == -1) {
180 perror("RTC_UIE_OFF ioctl");
181 exit(errno);
182 }
183
184 test_READ:
185 /* Read the RTC time/date */
186 retval = ioctl(fd, RTC_RD_TIME, &rtc_tm);
187 if (retval == -1) {
188 perror("RTC_RD_TIME ioctl");
189 exit(errno);
190 }
191
192 fprintf(stderr, "\n\nCurrent RTC date/time is %d-%d-%d, %02d:%02d:%02d.\n",
193 rtc_tm.tm_mday, rtc_tm.tm_mon + 1, rtc_tm.tm_year + 1900,
194 rtc_tm.tm_hour, rtc_tm.tm_min, rtc_tm.tm_sec);
195
196 /* Set the alarm to 5 sec in the future, and check for rollover */
197 rtc_tm.tm_sec += 5;
198 if (rtc_tm.tm_sec >= 60) {
199 rtc_tm.tm_sec %= 60;
200 rtc_tm.tm_min++;
201 }
202 if (rtc_tm.tm_min == 60) {
203 rtc_tm.tm_min = 0;
204 rtc_tm.tm_hour++;
205 }
206 if (rtc_tm.tm_hour == 24)
207 rtc_tm.tm_hour = 0;
208
209 retval = ioctl(fd, RTC_ALM_SET, &rtc_tm);
210 if (retval == -1) {
211 if (errno == EINVAL) {
212 fprintf(stderr,
213 "\n...Alarm IRQs not supported.\n");
214 goto test_PIE;
215 }
216
217 perror("RTC_ALM_SET ioctl");
218 exit(errno);
219 }
220
221 /* Read the current alarm settings */
222 retval = ioctl(fd, RTC_ALM_READ, &rtc_tm);
223 if (retval == -1) {
224 if (errno == EINVAL) {
225 fprintf(stderr,
226 "\n...EINVAL reading current alarm setting.\n");
227 goto test_PIE;
228 }
229 perror("RTC_ALM_READ ioctl");
230 exit(errno);
231 }
232
233 fprintf(stderr, "Alarm time now set to %02d:%02d:%02d.\n",
234 rtc_tm.tm_hour, rtc_tm.tm_min, rtc_tm.tm_sec);
235
236 /* Enable alarm interrupts */
237 retval = ioctl(fd, RTC_AIE_ON, 0);
238 if (retval == -1) {
239 if (errno == EINVAL || errno == EIO) {
240 fprintf(stderr,
241 "\n...Alarm IRQs not supported.\n");
242 goto test_PIE;
243 }
244
245 perror("RTC_AIE_ON ioctl");
246 exit(errno);
247 }
248
249 fprintf(stderr, "Waiting 5 seconds for alarm...");
250 fflush(stderr);
251 /* This blocks until the alarm ring causes an interrupt */
252 retval = read(fd, &data, sizeof(unsigned long));
253 if (retval == -1) {
254 perror("read");
255 exit(errno);
256 }
257 irqcount++;
258 fprintf(stderr, " okay. Alarm rang.\n");
259
260 /* Disable alarm interrupts */
261 retval = ioctl(fd, RTC_AIE_OFF, 0);
262 if (retval == -1) {
263 perror("RTC_AIE_OFF ioctl");
264 exit(errno);
265 }
266
267 test_PIE:
268 /* Read periodic IRQ rate */
269 retval = ioctl(fd, RTC_IRQP_READ, &tmp);
270 if (retval == -1) {
271 /* not all RTCs support periodic IRQs */
272 if (errno == EINVAL) {
273 fprintf(stderr, "\nNo periodic IRQ support\n");
274 goto test_DATE;
275 }
276 perror("RTC_IRQP_READ ioctl");
277 exit(errno);
278 }
279 fprintf(stderr, "\nPeriodic IRQ rate is %ldHz.\n", tmp);
280
281 fprintf(stderr, "Counting 20 interrupts at:");
282 fflush(stderr);
283
284 /* The frequencies 128Hz, 256Hz, ... 8192Hz are only allowed for root. */
285 for (tmp=2; tmp<=64; tmp*=2) {
286
287 retval = ioctl(fd, RTC_IRQP_SET, tmp);
288 if (retval == -1) {
289 /* not all RTCs can change their periodic IRQ rate */
290 if (errno == EINVAL) {
291 fprintf(stderr,
292 "\n...Periodic IRQ rate is fixed\n");
293 goto test_DATE;
294 }
295 perror("RTC_IRQP_SET ioctl");
296 exit(errno);
297 }
298
299 fprintf(stderr, "\n%ldHz:\t", tmp);
300 fflush(stderr);
301
302 /* Enable periodic interrupts */
303 retval = ioctl(fd, RTC_PIE_ON, 0);
304 if (retval == -1) {
305 perror("RTC_PIE_ON ioctl");
306 exit(errno);
307 }
308
309 for (i=1; i<21; i++) {
310 gettimeofday(&start, NULL);
311 /* This blocks */
312 retval = read(fd, &data, sizeof(unsigned long));
313 if (retval == -1) {
314 perror("read");
315 exit(errno);
316 }
317 gettimeofday(&end, NULL);
318 timersub(&end, &start, &diff);
319 if (diff.tv_sec > 0 ||
320 diff.tv_usec > ((1000000L / tmp) * 1.10)) {
321 fprintf(stderr, "\nPIE delta error: %ld.%06ld should be close to 0.%06ld\n",
322 diff.tv_sec, diff.tv_usec,
323 (1000000L / tmp));
324 fflush(stdout);
325 exit(-1);
326 }
327
328 fprintf(stderr, " %d",i);
329 fflush(stderr);
330 irqcount++;
331 }
332
333 /* Disable periodic interrupts */
334 retval = ioctl(fd, RTC_PIE_OFF, 0);
335 if (retval == -1) {
336 perror("RTC_PIE_OFF ioctl");
337 exit(errno);
338 }
339 }
340
341 test_DATE:
342 if (!dangerous)
343 goto done;
344
345 fprintf(stderr, "\nTesting problematic dates\n");
346
347 for (i = 0; i < ARRAY_SIZE(cutoff_dates); i++) {
348 struct rtc_time current;
349
350 /* Write the new date in RTC */
351 retval = ioctl(fd, RTC_SET_TIME, &cutoff_dates[i]);
352 if (retval == -1) {
353 perror("RTC_SET_TIME ioctl");
354 close(fd);
355 exit(errno);
356 }
357
358 /* Read back */
359 retval = ioctl(fd, RTC_RD_TIME, ¤t);
360 if (retval == -1) {
361 perror("RTC_RD_TIME ioctl");
362 exit(errno);
363 }
364
365 if(compare_dates(&cutoff_dates[i], ¤t)) {
366 fprintf(stderr,"Setting date %d failed\n",
367 cutoff_dates[i].tm_year + 1900);
368 goto done;
369 }
370
371 cutoff_dates[i].tm_sec += 5;
372
373 /* Write the new alarm in RTC */
374 retval = ioctl(fd, RTC_ALM_SET, &cutoff_dates[i]);
375 if (retval == -1) {
376 perror("RTC_ALM_SET ioctl");
377 close(fd);
378 exit(errno);
379 }
380
381 /* Read back */
382 retval = ioctl(fd, RTC_ALM_READ, ¤t);
383 if (retval == -1) {
384 perror("RTC_ALM_READ ioctl");
385 exit(errno);
386 }
387
388 if(compare_dates(&cutoff_dates[i], ¤t)) {
389 fprintf(stderr,"Setting alarm %d failed\n",
390 cutoff_dates[i].tm_year + 1900);
391 goto done;
392 }
393
394 fprintf(stderr, "Setting year %d is OK \n",
395 cutoff_dates[i].tm_year + 1900);
396 }
397 done:
398 fprintf(stderr, "\n\n\t\t\t *** Test complete ***\n");
399
400 close(fd);
401
402 return 0;
403 }
404