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 #ifdef __ANDROID__
126 	/*
127 	 * Android does not rely on update interrupts so do not test them.
128 	 */
129 	goto test_READ;
130 #endif
131 
132 	/* Turn on update interrupts (one per second) */
133 	retval = ioctl(fd, RTC_UIE_ON, 0);
134 	if (retval == -1) {
135 		if (errno == EINVAL) {
136 			fprintf(stderr,
137 				"\n...Update IRQs not supported.\n");
138 			goto test_READ;
139 		}
140 		perror("RTC_UIE_ON ioctl");
141 		exit(errno);
142 	}
143 
144 	fprintf(stderr, "Counting 5 update (1/sec) interrupts from reading %s:",
145 			rtc);
146 	fflush(stderr);
147 	for (i=1; i<6; i++) {
148 		/* This read will block */
149 		retval = read(fd, &data, sizeof(unsigned long));
150 		if (retval == -1) {
151 			perror("read");
152 			exit(errno);
153 		}
154 		fprintf(stderr, " %d",i);
155 		fflush(stderr);
156 		irqcount++;
157 	}
158 
159 	fprintf(stderr, "\nAgain, from using select(2) on /dev/rtc:");
160 	fflush(stderr);
161 	for (i=1; i<6; i++) {
162 		struct timeval tv = {5, 0};     /* 5 second timeout on select */
163 		fd_set readfds;
164 
165 		FD_ZERO(&readfds);
166 		FD_SET(fd, &readfds);
167 		/* The select will wait until an RTC interrupt happens. */
168 		retval = select(fd+1, &readfds, NULL, NULL, &tv);
169 		if (retval == -1) {
170 		        perror("select");
171 		        exit(errno);
172 		}
173 		/* This read won't block unlike the select-less case above. */
174 		retval = read(fd, &data, sizeof(unsigned long));
175 		if (retval == -1) {
176 		        perror("read");
177 		        exit(errno);
178 		}
179 		fprintf(stderr, " %d",i);
180 		fflush(stderr);
181 		irqcount++;
182 	}
183 
184 	/* Turn off update interrupts */
185 	retval = ioctl(fd, RTC_UIE_OFF, 0);
186 	if (retval == -1) {
187 		perror("RTC_UIE_OFF ioctl");
188 		exit(errno);
189 	}
190 
191 test_READ:
192 	/* Read the RTC time/date */
193 	retval = ioctl(fd, RTC_RD_TIME, &rtc_tm);
194 	if (retval == -1) {
195 		perror("RTC_RD_TIME ioctl");
196 		exit(errno);
197 	}
198 
199 	fprintf(stderr, "\n\nCurrent RTC date/time is %d-%d-%d, %02d:%02d:%02d.\n",
200 		rtc_tm.tm_mday, rtc_tm.tm_mon + 1, rtc_tm.tm_year + 1900,
201 		rtc_tm.tm_hour, rtc_tm.tm_min, rtc_tm.tm_sec);
202 
203 	/* Set the alarm to 5 sec in the future, and check for rollover */
204 	rtc_tm.tm_sec += 5;
205 	if (rtc_tm.tm_sec >= 60) {
206 		rtc_tm.tm_sec %= 60;
207 		rtc_tm.tm_min++;
208 	}
209 	if (rtc_tm.tm_min == 60) {
210 		rtc_tm.tm_min = 0;
211 		rtc_tm.tm_hour++;
212 	}
213 	if (rtc_tm.tm_hour == 24)
214 		rtc_tm.tm_hour = 0;
215 
216 	retval = ioctl(fd, RTC_ALM_SET, &rtc_tm);
217 	if (retval == -1) {
218 		if (errno == EINVAL) {
219 			fprintf(stderr,
220 				"\n...Alarm IRQs not supported.\n");
221 			goto test_PIE;
222 		}
223 
224 		perror("RTC_ALM_SET ioctl");
225 		exit(errno);
226 	}
227 
228 	/* Read the current alarm settings */
229 	retval = ioctl(fd, RTC_ALM_READ, &rtc_tm);
230 	if (retval == -1) {
231 		if (errno == EINVAL) {
232 			fprintf(stderr,
233 					"\n...EINVAL reading current alarm setting.\n");
234 			goto test_PIE;
235 		}
236 		perror("RTC_ALM_READ ioctl");
237 		exit(errno);
238 	}
239 
240 	fprintf(stderr, "Alarm time now set to %02d:%02d:%02d.\n",
241 		rtc_tm.tm_hour, rtc_tm.tm_min, rtc_tm.tm_sec);
242 
243 	/* Enable alarm interrupts */
244 	retval = ioctl(fd, RTC_AIE_ON, 0);
245 	if (retval == -1) {
246 		if (errno == EINVAL || errno == EIO) {
247 			fprintf(stderr,
248 				"\n...Alarm IRQs not supported.\n");
249 			goto test_PIE;
250 		}
251 
252 		perror("RTC_AIE_ON ioctl");
253 		exit(errno);
254 	}
255 
256 	fprintf(stderr, "Waiting 5 seconds for alarm...");
257 	fflush(stderr);
258 	/* This blocks until the alarm ring causes an interrupt */
259 	retval = read(fd, &data, sizeof(unsigned long));
260 	if (retval == -1) {
261 		perror("read");
262 		exit(errno);
263 	}
264 	irqcount++;
265 	fprintf(stderr, " okay. Alarm rang.\n");
266 
267 	/* Disable alarm interrupts */
268 	retval = ioctl(fd, RTC_AIE_OFF, 0);
269 	if (retval == -1) {
270 		perror("RTC_AIE_OFF ioctl");
271 		exit(errno);
272 	}
273 
274 #ifdef __ANDROID__
275 	/*
276 	 * Android does not rely on periodic IRQs so do not test them.
277 	 */
278 	goto done;
279 #endif
280 
281 test_PIE:
282 	/* Read periodic IRQ rate */
283 	retval = ioctl(fd, RTC_IRQP_READ, &tmp);
284 	if (retval == -1) {
285 		/* not all RTCs support periodic IRQs */
286 		if (errno == EINVAL) {
287 			fprintf(stderr, "\nNo periodic IRQ support\n");
288 			goto test_DATE;
289 		}
290 		perror("RTC_IRQP_READ ioctl");
291 		exit(errno);
292 	}
293 	fprintf(stderr, "\nPeriodic IRQ rate is %ldHz.\n", tmp);
294 
295 	fprintf(stderr, "Counting 20 interrupts at:");
296 	fflush(stderr);
297 
298 	/* The frequencies 128Hz, 256Hz, ... 8192Hz are only allowed for root. */
299 	for (tmp=2; tmp<=64; tmp*=2) {
300 
301 		retval = ioctl(fd, RTC_IRQP_SET, tmp);
302 		if (retval == -1) {
303 			/* not all RTCs can change their periodic IRQ rate */
304 			if (errno == EINVAL) {
305 				fprintf(stderr,
306 					"\n...Periodic IRQ rate is fixed\n");
307 				goto test_DATE;
308 			}
309 			perror("RTC_IRQP_SET ioctl");
310 			exit(errno);
311 		}
312 
313 		fprintf(stderr, "\n%ldHz:\t", tmp);
314 		fflush(stderr);
315 
316 		/* Enable periodic interrupts */
317 		retval = ioctl(fd, RTC_PIE_ON, 0);
318 		if (retval == -1) {
319 			perror("RTC_PIE_ON ioctl");
320 			exit(errno);
321 		}
322 
323 		for (i=1; i<21; i++) {
324 			gettimeofday(&start, NULL);
325 			/* This blocks */
326 			retval = read(fd, &data, sizeof(unsigned long));
327 			if (retval == -1) {
328 				perror("read");
329 				exit(errno);
330 			}
331 			gettimeofday(&end, NULL);
332 			timersub(&end, &start, &diff);
333 			if (diff.tv_sec > 0 ||
334 			    diff.tv_usec > ((1000000L / tmp) * 1.10)) {
335 				fprintf(stderr, "\nPIE delta error: %ld.%06ld should be close to 0.%06ld\n",
336 				       diff.tv_sec, diff.tv_usec,
337 				       (1000000L / tmp));
338 				fflush(stdout);
339 				exit(-1);
340 			}
341 
342 			fprintf(stderr, " %d",i);
343 			fflush(stderr);
344 			irqcount++;
345 		}
346 
347 		/* Disable periodic interrupts */
348 		retval = ioctl(fd, RTC_PIE_OFF, 0);
349 		if (retval == -1) {
350 			perror("RTC_PIE_OFF ioctl");
351 			exit(errno);
352 		}
353 	}
354 
355 test_DATE:
356 	if (!dangerous)
357 		goto done;
358 
359 	fprintf(stderr, "\nTesting problematic dates\n");
360 
361 	for (i = 0; i < ARRAY_SIZE(cutoff_dates); i++) {
362 		struct rtc_time current;
363 
364 		/* Write the new date in RTC */
365 		retval = ioctl(fd, RTC_SET_TIME, &cutoff_dates[i]);
366 		if (retval == -1) {
367 			perror("RTC_SET_TIME ioctl");
368 			close(fd);
369 			exit(errno);
370 		}
371 
372 		/* Read back */
373 		retval = ioctl(fd, RTC_RD_TIME, &current);
374 		if (retval == -1) {
375 			perror("RTC_RD_TIME ioctl");
376 			exit(errno);
377 		}
378 
379 		if(compare_dates(&cutoff_dates[i], &current)) {
380 			fprintf(stderr,"Setting date %d failed\n",
381 			        cutoff_dates[i].tm_year + 1900);
382 			goto done;
383 		}
384 
385 		cutoff_dates[i].tm_sec += 5;
386 
387 		/* Write the new alarm in RTC */
388 		retval = ioctl(fd, RTC_ALM_SET, &cutoff_dates[i]);
389 		if (retval == -1) {
390 			perror("RTC_ALM_SET ioctl");
391 			close(fd);
392 			exit(errno);
393 		}
394 
395 		/* Read back */
396 		retval = ioctl(fd, RTC_ALM_READ, &current);
397 		if (retval == -1) {
398 			perror("RTC_ALM_READ ioctl");
399 			exit(errno);
400 		}
401 
402 		if(compare_dates(&cutoff_dates[i], &current)) {
403 			fprintf(stderr,"Setting alarm %d failed\n",
404 			        cutoff_dates[i].tm_year + 1900);
405 			goto done;
406 		}
407 
408 		fprintf(stderr, "Setting year %d is OK \n",
409 			cutoff_dates[i].tm_year + 1900);
410 	}
411 done:
412 	fprintf(stderr, "\n\n\t\t\t *** Test complete ***\n");
413 
414 	close(fd);
415 
416 	return 0;
417 }
418