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Alessandro Zummo0c86edc2006-03-27 01:16:37 -08001/*
2 * RTC subsystem, interface functions
3 *
4 * Copyright (C) 2005 Tower Technologies
5 * Author: Alessandro Zummo <a.zummo@towertech.it>
6 *
7 * based on arch/arm/common/rtctime.c
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12*/
13
14#include <linux/rtc.h>
Alexey Dobriyand43c36d2009-10-07 17:09:06 +040015#include <linux/sched.h>
Paul Gortmaker21138522011-05-27 09:57:25 -040016#include <linux/module.h>
David Brownell97144c62007-10-16 01:28:16 -070017#include <linux/log2.h>
John Stultz6610e082010-09-23 15:07:34 -070018#include <linux/workqueue.h>
19
John Stultzaa0be0f2011-01-20 15:26:12 -080020static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer);
21static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer);
22
John Stultz6610e082010-09-23 15:07:34 -070023static int __rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
24{
25 int err;
26 if (!rtc->ops)
27 err = -ENODEV;
28 else if (!rtc->ops->read_time)
29 err = -EINVAL;
30 else {
31 memset(tm, 0, sizeof(struct rtc_time));
32 err = rtc->ops->read_time(rtc->dev.parent, tm);
Hyogi Gim16682c862014-12-10 15:52:27 -080033 if (err < 0) {
34 dev_err(&rtc->dev, "read_time: fail to read\n");
35 return err;
36 }
37
38 err = rtc_valid_tm(tm);
39 if (err < 0)
40 dev_err(&rtc->dev, "read_time: rtc_time isn't valid\n");
John Stultz6610e082010-09-23 15:07:34 -070041 }
42 return err;
43}
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080044
David Brownellab6a2d72007-05-08 00:33:30 -070045int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080046{
47 int err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080048
49 err = mutex_lock_interruptible(&rtc->ops_lock);
50 if (err)
David Brownellb68bb262008-07-29 22:33:30 -070051 return err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080052
John Stultz6610e082010-09-23 15:07:34 -070053 err = __rtc_read_time(rtc, tm);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080054 mutex_unlock(&rtc->ops_lock);
55 return err;
56}
57EXPORT_SYMBOL_GPL(rtc_read_time);
58
David Brownellab6a2d72007-05-08 00:33:30 -070059int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080060{
61 int err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080062
63 err = rtc_valid_tm(tm);
64 if (err != 0)
65 return err;
66
67 err = mutex_lock_interruptible(&rtc->ops_lock);
68 if (err)
David Brownellb68bb262008-07-29 22:33:30 -070069 return err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080070
71 if (!rtc->ops)
72 err = -ENODEV;
Alessandro Zummobbccf832009-01-06 14:42:21 -080073 else if (rtc->ops->set_time)
David Brownellcd966202007-05-08 00:33:40 -070074 err = rtc->ops->set_time(rtc->dev.parent, tm);
Alessandro Zummobbccf832009-01-06 14:42:21 -080075 else if (rtc->ops->set_mmss) {
76 unsigned long secs;
77 err = rtc_tm_to_time(tm, &secs);
78 if (err == 0)
79 err = rtc->ops->set_mmss(rtc->dev.parent, secs);
80 } else
81 err = -EINVAL;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080082
Zoran Markovic14d0e342013-06-26 16:09:13 -070083 pm_stay_awake(rtc->dev.parent);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080084 mutex_unlock(&rtc->ops_lock);
NeilBrown5f9679d2011-12-09 09:39:15 +110085 /* A timer might have just expired */
86 schedule_work(&rtc->irqwork);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080087 return err;
88}
89EXPORT_SYMBOL_GPL(rtc_set_time);
90
David Brownellab6a2d72007-05-08 00:33:30 -070091int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080092{
93 int err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080094
95 err = mutex_lock_interruptible(&rtc->ops_lock);
96 if (err)
David Brownellb68bb262008-07-29 22:33:30 -070097 return err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -080098
99 if (!rtc->ops)
100 err = -ENODEV;
101 else if (rtc->ops->set_mmss)
David Brownellcd966202007-05-08 00:33:40 -0700102 err = rtc->ops->set_mmss(rtc->dev.parent, secs);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800103 else if (rtc->ops->read_time && rtc->ops->set_time) {
104 struct rtc_time new, old;
105
David Brownellcd966202007-05-08 00:33:40 -0700106 err = rtc->ops->read_time(rtc->dev.parent, &old);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800107 if (err == 0) {
108 rtc_time_to_tm(secs, &new);
109
110 /*
111 * avoid writing when we're going to change the day of
112 * the month. We will retry in the next minute. This
113 * basically means that if the RTC must not drift
114 * by more than 1 minute in 11 minutes.
115 */
116 if (!((old.tm_hour == 23 && old.tm_min == 59) ||
117 (new.tm_hour == 23 && new.tm_min == 59)))
David Brownellcd966202007-05-08 00:33:40 -0700118 err = rtc->ops->set_time(rtc->dev.parent,
David Brownellab6a2d72007-05-08 00:33:30 -0700119 &new);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800120 }
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700121 } else {
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800122 err = -EINVAL;
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700123 }
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800124
Zoran Markovic14d0e342013-06-26 16:09:13 -0700125 pm_stay_awake(rtc->dev.parent);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800126 mutex_unlock(&rtc->ops_lock);
NeilBrown5f9679d2011-12-09 09:39:15 +1100127 /* A timer might have just expired */
128 schedule_work(&rtc->irqwork);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800129
130 return err;
131}
132EXPORT_SYMBOL_GPL(rtc_set_mmss);
133
John Stultzf44f7f92011-02-21 22:58:51 -0800134static int rtc_read_alarm_internal(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
135{
136 int err;
137
138 err = mutex_lock_interruptible(&rtc->ops_lock);
139 if (err)
140 return err;
141
142 if (rtc->ops == NULL)
143 err = -ENODEV;
144 else if (!rtc->ops->read_alarm)
145 err = -EINVAL;
146 else {
147 memset(alarm, 0, sizeof(struct rtc_wkalrm));
148 err = rtc->ops->read_alarm(rtc->dev.parent, alarm);
149 }
150
151 mutex_unlock(&rtc->ops_lock);
152 return err;
153}
154
155int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
156{
157 int err;
158 struct rtc_time before, now;
159 int first_time = 1;
160 unsigned long t_now, t_alm;
161 enum { none, day, month, year } missing = none;
162 unsigned days;
163
164 /* The lower level RTC driver may return -1 in some fields,
165 * creating invalid alarm->time values, for reasons like:
166 *
167 * - The hardware may not be capable of filling them in;
168 * many alarms match only on time-of-day fields, not
169 * day/month/year calendar data.
170 *
171 * - Some hardware uses illegal values as "wildcard" match
172 * values, which non-Linux firmware (like a BIOS) may try
173 * to set up as e.g. "alarm 15 minutes after each hour".
174 * Linux uses only oneshot alarms.
175 *
176 * When we see that here, we deal with it by using values from
177 * a current RTC timestamp for any missing (-1) values. The
178 * RTC driver prevents "periodic alarm" modes.
179 *
180 * But this can be racey, because some fields of the RTC timestamp
181 * may have wrapped in the interval since we read the RTC alarm,
182 * which would lead to us inserting inconsistent values in place
183 * of the -1 fields.
184 *
185 * Reading the alarm and timestamp in the reverse sequence
186 * would have the same race condition, and not solve the issue.
187 *
188 * So, we must first read the RTC timestamp,
189 * then read the RTC alarm value,
190 * and then read a second RTC timestamp.
191 *
192 * If any fields of the second timestamp have changed
193 * when compared with the first timestamp, then we know
194 * our timestamp may be inconsistent with that used by
195 * the low-level rtc_read_alarm_internal() function.
196 *
197 * So, when the two timestamps disagree, we just loop and do
198 * the process again to get a fully consistent set of values.
199 *
200 * This could all instead be done in the lower level driver,
201 * but since more than one lower level RTC implementation needs it,
202 * then it's probably best best to do it here instead of there..
203 */
204
205 /* Get the "before" timestamp */
206 err = rtc_read_time(rtc, &before);
207 if (err < 0)
208 return err;
209 do {
210 if (!first_time)
211 memcpy(&before, &now, sizeof(struct rtc_time));
212 first_time = 0;
213
214 /* get the RTC alarm values, which may be incomplete */
215 err = rtc_read_alarm_internal(rtc, alarm);
216 if (err)
217 return err;
218
219 /* full-function RTCs won't have such missing fields */
220 if (rtc_valid_tm(&alarm->time) == 0)
221 return 0;
222
223 /* get the "after" timestamp, to detect wrapped fields */
224 err = rtc_read_time(rtc, &now);
225 if (err < 0)
226 return err;
227
228 /* note that tm_sec is a "don't care" value here: */
229 } while ( before.tm_min != now.tm_min
230 || before.tm_hour != now.tm_hour
231 || before.tm_mon != now.tm_mon
232 || before.tm_year != now.tm_year);
233
234 /* Fill in the missing alarm fields using the timestamp; we
235 * know there's at least one since alarm->time is invalid.
236 */
237 if (alarm->time.tm_sec == -1)
238 alarm->time.tm_sec = now.tm_sec;
239 if (alarm->time.tm_min == -1)
240 alarm->time.tm_min = now.tm_min;
241 if (alarm->time.tm_hour == -1)
242 alarm->time.tm_hour = now.tm_hour;
243
244 /* For simplicity, only support date rollover for now */
Ben Hutchingse74a8f22012-01-10 15:11:02 -0800245 if (alarm->time.tm_mday < 1 || alarm->time.tm_mday > 31) {
John Stultzf44f7f92011-02-21 22:58:51 -0800246 alarm->time.tm_mday = now.tm_mday;
247 missing = day;
248 }
Ben Hutchingse74a8f22012-01-10 15:11:02 -0800249 if ((unsigned)alarm->time.tm_mon >= 12) {
John Stultzf44f7f92011-02-21 22:58:51 -0800250 alarm->time.tm_mon = now.tm_mon;
251 if (missing == none)
252 missing = month;
253 }
254 if (alarm->time.tm_year == -1) {
255 alarm->time.tm_year = now.tm_year;
256 if (missing == none)
257 missing = year;
258 }
259
260 /* with luck, no rollover is needed */
261 rtc_tm_to_time(&now, &t_now);
262 rtc_tm_to_time(&alarm->time, &t_alm);
263 if (t_now < t_alm)
264 goto done;
265
266 switch (missing) {
267
268 /* 24 hour rollover ... if it's now 10am Monday, an alarm that
269 * that will trigger at 5am will do so at 5am Tuesday, which
270 * could also be in the next month or year. This is a common
271 * case, especially for PCs.
272 */
273 case day:
274 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "day");
275 t_alm += 24 * 60 * 60;
276 rtc_time_to_tm(t_alm, &alarm->time);
277 break;
278
279 /* Month rollover ... if it's the 31th, an alarm on the 3rd will
280 * be next month. An alarm matching on the 30th, 29th, or 28th
281 * may end up in the month after that! Many newer PCs support
282 * this type of alarm.
283 */
284 case month:
285 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "month");
286 do {
287 if (alarm->time.tm_mon < 11)
288 alarm->time.tm_mon++;
289 else {
290 alarm->time.tm_mon = 0;
291 alarm->time.tm_year++;
292 }
293 days = rtc_month_days(alarm->time.tm_mon,
294 alarm->time.tm_year);
295 } while (days < alarm->time.tm_mday);
296 break;
297
298 /* Year rollover ... easy except for leap years! */
299 case year:
300 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "year");
301 do {
302 alarm->time.tm_year++;
Ales Novakee1d9012014-06-06 14:35:39 -0700303 } while (!is_leap_year(alarm->time.tm_year + 1900)
304 && rtc_valid_tm(&alarm->time) != 0);
John Stultzf44f7f92011-02-21 22:58:51 -0800305 break;
306
307 default:
308 dev_warn(&rtc->dev, "alarm rollover not handled\n");
309 }
310
311done:
Ales Novakee1d9012014-06-06 14:35:39 -0700312 err = rtc_valid_tm(&alarm->time);
313
314 if (err) {
315 dev_warn(&rtc->dev, "invalid alarm value: %d-%d-%d %d:%d:%d\n",
316 alarm->time.tm_year + 1900, alarm->time.tm_mon + 1,
317 alarm->time.tm_mday, alarm->time.tm_hour, alarm->time.tm_min,
318 alarm->time.tm_sec);
319 }
320
321 return err;
John Stultzf44f7f92011-02-21 22:58:51 -0800322}
323
John Stultz6610e082010-09-23 15:07:34 -0700324int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800325{
326 int err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800327
328 err = mutex_lock_interruptible(&rtc->ops_lock);
329 if (err)
David Brownellb68bb262008-07-29 22:33:30 -0700330 return err;
John Stultzd5553a52011-01-20 15:26:13 -0800331 if (rtc->ops == NULL)
332 err = -ENODEV;
333 else if (!rtc->ops->read_alarm)
334 err = -EINVAL;
335 else {
336 memset(alarm, 0, sizeof(struct rtc_wkalrm));
337 alarm->enabled = rtc->aie_timer.enabled;
John Stultz6610e082010-09-23 15:07:34 -0700338 alarm->time = rtc_ktime_to_tm(rtc->aie_timer.node.expires);
John Stultzd5553a52011-01-20 15:26:13 -0800339 }
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800340 mutex_unlock(&rtc->ops_lock);
Mark Lord0e36a9a2007-10-16 01:28:21 -0700341
John Stultzd5553a52011-01-20 15:26:13 -0800342 return err;
Mark Lord0e36a9a2007-10-16 01:28:21 -0700343}
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800344EXPORT_SYMBOL_GPL(rtc_read_alarm);
345
Mark Brownd576fe42011-06-01 11:13:16 +0100346static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
John Stultz6610e082010-09-23 15:07:34 -0700347{
348 struct rtc_time tm;
349 long now, scheduled;
350 int err;
351
352 err = rtc_valid_tm(&alarm->time);
353 if (err)
354 return err;
355 rtc_tm_to_time(&alarm->time, &scheduled);
356
357 /* Make sure we're not setting alarms in the past */
358 err = __rtc_read_time(rtc, &tm);
Hyogi Gimca6dc2d2014-08-08 14:20:11 -0700359 if (err)
360 return err;
John Stultz6610e082010-09-23 15:07:34 -0700361 rtc_tm_to_time(&tm, &now);
362 if (scheduled <= now)
363 return -ETIME;
364 /*
365 * XXX - We just checked to make sure the alarm time is not
366 * in the past, but there is still a race window where if
367 * the is alarm set for the next second and the second ticks
368 * over right here, before we set the alarm.
369 */
370
Linus Torvalds157e8bf2012-01-03 17:32:13 -0800371 if (!rtc->ops)
372 err = -ENODEV;
373 else if (!rtc->ops->set_alarm)
374 err = -EINVAL;
375 else
376 err = rtc->ops->set_alarm(rtc->dev.parent, alarm);
377
378 return err;
John Stultz6610e082010-09-23 15:07:34 -0700379}
380
David Brownellab6a2d72007-05-08 00:33:30 -0700381int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800382{
383 int err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800384
David Brownellf8245c22007-05-08 00:34:07 -0700385 err = rtc_valid_tm(&alarm->time);
386 if (err != 0)
387 return err;
388
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800389 err = mutex_lock_interruptible(&rtc->ops_lock);
390 if (err)
David Brownellb68bb262008-07-29 22:33:30 -0700391 return err;
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700392 if (rtc->aie_timer.enabled)
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100393 rtc_timer_remove(rtc, &rtc->aie_timer);
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700394
John Stultz6610e082010-09-23 15:07:34 -0700395 rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
396 rtc->aie_timer.period = ktime_set(0, 0);
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700397 if (alarm->enabled)
John Stultzaa0be0f2011-01-20 15:26:12 -0800398 err = rtc_timer_enqueue(rtc, &rtc->aie_timer);
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700399
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800400 mutex_unlock(&rtc->ops_lock);
John Stultzaa0be0f2011-01-20 15:26:12 -0800401 return err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800402}
403EXPORT_SYMBOL_GPL(rtc_set_alarm);
404
John Stultzf6d5b332011-03-29 18:00:27 -0700405/* Called once per device from rtc_device_register */
406int rtc_initialize_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
407{
408 int err;
John Stultzbd729d72012-01-05 15:21:19 -0800409 struct rtc_time now;
John Stultzf6d5b332011-03-29 18:00:27 -0700410
411 err = rtc_valid_tm(&alarm->time);
412 if (err != 0)
413 return err;
414
John Stultzbd729d72012-01-05 15:21:19 -0800415 err = rtc_read_time(rtc, &now);
416 if (err)
417 return err;
418
John Stultzf6d5b332011-03-29 18:00:27 -0700419 err = mutex_lock_interruptible(&rtc->ops_lock);
420 if (err)
421 return err;
422
423 rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
424 rtc->aie_timer.period = ktime_set(0, 0);
John Stultzbd729d72012-01-05 15:21:19 -0800425
426 /* Alarm has to be enabled & in the futrure for us to enqueue it */
427 if (alarm->enabled && (rtc_tm_to_ktime(now).tv64 <
428 rtc->aie_timer.node.expires.tv64)) {
429
John Stultzf6d5b332011-03-29 18:00:27 -0700430 rtc->aie_timer.enabled = 1;
431 timerqueue_add(&rtc->timerqueue, &rtc->aie_timer.node);
432 }
433 mutex_unlock(&rtc->ops_lock);
434 return err;
435}
436EXPORT_SYMBOL_GPL(rtc_initialize_alarm);
437
438
439
Alessandro Zummo099e6572009-01-04 12:00:54 -0800440int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled)
441{
442 int err = mutex_lock_interruptible(&rtc->ops_lock);
443 if (err)
444 return err;
445
John Stultz6610e082010-09-23 15:07:34 -0700446 if (rtc->aie_timer.enabled != enabled) {
John Stultzaa0be0f2011-01-20 15:26:12 -0800447 if (enabled)
448 err = rtc_timer_enqueue(rtc, &rtc->aie_timer);
449 else
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100450 rtc_timer_remove(rtc, &rtc->aie_timer);
John Stultz6610e082010-09-23 15:07:34 -0700451 }
452
John Stultzaa0be0f2011-01-20 15:26:12 -0800453 if (err)
Uwe Kleine-König516373b2011-02-14 11:33:17 +0100454 /* nothing */;
455 else if (!rtc->ops)
Alessandro Zummo099e6572009-01-04 12:00:54 -0800456 err = -ENODEV;
457 else if (!rtc->ops->alarm_irq_enable)
458 err = -EINVAL;
459 else
460 err = rtc->ops->alarm_irq_enable(rtc->dev.parent, enabled);
461
462 mutex_unlock(&rtc->ops_lock);
463 return err;
464}
465EXPORT_SYMBOL_GPL(rtc_alarm_irq_enable);
466
467int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
468{
469 int err = mutex_lock_interruptible(&rtc->ops_lock);
470 if (err)
471 return err;
472
John Stultz456d66e2011-02-11 18:15:23 -0800473#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
474 if (enabled == 0 && rtc->uie_irq_active) {
475 mutex_unlock(&rtc->ops_lock);
476 return rtc_dev_update_irq_enable_emul(rtc, 0);
477 }
478#endif
John Stultz6610e082010-09-23 15:07:34 -0700479 /* make sure we're changing state */
480 if (rtc->uie_rtctimer.enabled == enabled)
481 goto out;
482
John Stultz4a649902012-03-06 17:16:09 -0800483 if (rtc->uie_unsupported) {
484 err = -EINVAL;
485 goto out;
486 }
487
John Stultz6610e082010-09-23 15:07:34 -0700488 if (enabled) {
489 struct rtc_time tm;
490 ktime_t now, onesec;
491
492 __rtc_read_time(rtc, &tm);
493 onesec = ktime_set(1, 0);
494 now = rtc_tm_to_ktime(tm);
495 rtc->uie_rtctimer.node.expires = ktime_add(now, onesec);
496 rtc->uie_rtctimer.period = ktime_set(1, 0);
John Stultzaa0be0f2011-01-20 15:26:12 -0800497 err = rtc_timer_enqueue(rtc, &rtc->uie_rtctimer);
498 } else
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100499 rtc_timer_remove(rtc, &rtc->uie_rtctimer);
Alessandro Zummo099e6572009-01-04 12:00:54 -0800500
John Stultz6610e082010-09-23 15:07:34 -0700501out:
Alessandro Zummo099e6572009-01-04 12:00:54 -0800502 mutex_unlock(&rtc->ops_lock);
John Stultz456d66e2011-02-11 18:15:23 -0800503#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
504 /*
505 * Enable emulation if the driver did not provide
506 * the update_irq_enable function pointer or if returned
507 * -EINVAL to signal that it has been configured without
508 * interrupts or that are not available at the moment.
509 */
510 if (err == -EINVAL)
511 err = rtc_dev_update_irq_enable_emul(rtc, enabled);
512#endif
Alessandro Zummo099e6572009-01-04 12:00:54 -0800513 return err;
John Stultz6610e082010-09-23 15:07:34 -0700514
Alessandro Zummo099e6572009-01-04 12:00:54 -0800515}
516EXPORT_SYMBOL_GPL(rtc_update_irq_enable);
517
John Stultz6610e082010-09-23 15:07:34 -0700518
David Brownelld728b1e2006-11-25 11:09:28 -0800519/**
John Stultz6610e082010-09-23 15:07:34 -0700520 * rtc_handle_legacy_irq - AIE, UIE and PIE event hook
521 * @rtc: pointer to the rtc device
522 *
523 * This function is called when an AIE, UIE or PIE mode interrupt
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300524 * has occurred (or been emulated).
John Stultz6610e082010-09-23 15:07:34 -0700525 *
526 * Triggers the registered irq_task function callback.
527 */
John Stultz456d66e2011-02-11 18:15:23 -0800528void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode)
John Stultz6610e082010-09-23 15:07:34 -0700529{
530 unsigned long flags;
531
532 /* mark one irq of the appropriate mode */
533 spin_lock_irqsave(&rtc->irq_lock, flags);
534 rtc->irq_data = (rtc->irq_data + (num << 8)) | (RTC_IRQF|mode);
535 spin_unlock_irqrestore(&rtc->irq_lock, flags);
536
537 /* call the task func */
538 spin_lock_irqsave(&rtc->irq_task_lock, flags);
539 if (rtc->irq_task)
540 rtc->irq_task->func(rtc->irq_task->private_data);
541 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
542
543 wake_up_interruptible(&rtc->irq_queue);
544 kill_fasync(&rtc->async_queue, SIGIO, POLL_IN);
545}
546
547
548/**
549 * rtc_aie_update_irq - AIE mode rtctimer hook
550 * @private: pointer to the rtc_device
551 *
552 * This functions is called when the aie_timer expires.
553 */
554void rtc_aie_update_irq(void *private)
555{
556 struct rtc_device *rtc = (struct rtc_device *)private;
557 rtc_handle_legacy_irq(rtc, 1, RTC_AF);
558}
559
560
561/**
562 * rtc_uie_update_irq - UIE mode rtctimer hook
563 * @private: pointer to the rtc_device
564 *
565 * This functions is called when the uie_timer expires.
566 */
567void rtc_uie_update_irq(void *private)
568{
569 struct rtc_device *rtc = (struct rtc_device *)private;
570 rtc_handle_legacy_irq(rtc, 1, RTC_UF);
571}
572
573
574/**
575 * rtc_pie_update_irq - PIE mode hrtimer hook
576 * @timer: pointer to the pie mode hrtimer
577 *
578 * This function is used to emulate PIE mode interrupts
579 * using an hrtimer. This function is called when the periodic
580 * hrtimer expires.
581 */
582enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer)
583{
584 struct rtc_device *rtc;
585 ktime_t period;
586 int count;
587 rtc = container_of(timer, struct rtc_device, pie_timer);
588
589 period = ktime_set(0, NSEC_PER_SEC/rtc->irq_freq);
590 count = hrtimer_forward_now(timer, period);
591
592 rtc_handle_legacy_irq(rtc, count, RTC_PF);
593
594 return HRTIMER_RESTART;
595}
596
597/**
598 * rtc_update_irq - Triggered when a RTC interrupt occurs.
David Brownellab6a2d72007-05-08 00:33:30 -0700599 * @rtc: the rtc device
David Brownelld728b1e2006-11-25 11:09:28 -0800600 * @num: how many irqs are being reported (usually one)
601 * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
Atsushi Nemotoe6229bec2009-06-18 16:49:09 -0700602 * Context: any
David Brownelld728b1e2006-11-25 11:09:28 -0800603 */
David Brownellab6a2d72007-05-08 00:33:30 -0700604void rtc_update_irq(struct rtc_device *rtc,
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800605 unsigned long num, unsigned long events)
606{
Alessandro Zummo131c9cc2014-04-03 14:50:09 -0700607 if (unlikely(IS_ERR_OR_NULL(rtc)))
608 return;
609
NeilBrown7523cee2012-08-05 22:56:20 +0200610 pm_stay_awake(rtc->dev.parent);
John Stultz6610e082010-09-23 15:07:34 -0700611 schedule_work(&rtc->irqwork);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800612}
613EXPORT_SYMBOL_GPL(rtc_update_irq);
614
Michał Mirosław9f3b7952013-02-01 20:40:17 +0100615static int __rtc_match(struct device *dev, const void *data)
Dave Young71da8902008-01-22 14:00:34 +0800616{
Michał Mirosław9f3b7952013-02-01 20:40:17 +0100617 const char *name = data;
Dave Young71da8902008-01-22 14:00:34 +0800618
Kay Sieversd4afc762009-01-06 14:42:11 -0800619 if (strcmp(dev_name(dev), name) == 0)
Dave Young71da8902008-01-22 14:00:34 +0800620 return 1;
621 return 0;
622}
623
Michał Mirosław9f3b7952013-02-01 20:40:17 +0100624struct rtc_device *rtc_class_open(const char *name)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800625{
David Brownellcd966202007-05-08 00:33:40 -0700626 struct device *dev;
David Brownellab6a2d72007-05-08 00:33:30 -0700627 struct rtc_device *rtc = NULL;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800628
Greg Kroah-Hartman695794a2008-05-22 17:21:08 -0400629 dev = class_find_device(rtc_class, NULL, name, __rtc_match);
Dave Young71da8902008-01-22 14:00:34 +0800630 if (dev)
631 rtc = to_rtc_device(dev);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800632
David Brownellab6a2d72007-05-08 00:33:30 -0700633 if (rtc) {
634 if (!try_module_get(rtc->owner)) {
David Brownellcd966202007-05-08 00:33:40 -0700635 put_device(dev);
David Brownellab6a2d72007-05-08 00:33:30 -0700636 rtc = NULL;
637 }
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800638 }
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800639
David Brownellab6a2d72007-05-08 00:33:30 -0700640 return rtc;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800641}
642EXPORT_SYMBOL_GPL(rtc_class_open);
643
David Brownellab6a2d72007-05-08 00:33:30 -0700644void rtc_class_close(struct rtc_device *rtc)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800645{
David Brownellab6a2d72007-05-08 00:33:30 -0700646 module_put(rtc->owner);
David Brownellcd966202007-05-08 00:33:40 -0700647 put_device(&rtc->dev);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800648}
649EXPORT_SYMBOL_GPL(rtc_class_close);
650
David Brownellab6a2d72007-05-08 00:33:30 -0700651int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800652{
653 int retval = -EBUSY;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800654
655 if (task == NULL || task->func == NULL)
656 return -EINVAL;
657
Alessandro Zummod691eb92007-10-16 01:28:15 -0700658 /* Cannot register while the char dev is in use */
Jiri Kosina372a3022007-12-04 23:45:05 -0800659 if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags))
Alessandro Zummod691eb92007-10-16 01:28:15 -0700660 return -EBUSY;
661
David Brownelld728b1e2006-11-25 11:09:28 -0800662 spin_lock_irq(&rtc->irq_task_lock);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800663 if (rtc->irq_task == NULL) {
664 rtc->irq_task = task;
665 retval = 0;
666 }
David Brownelld728b1e2006-11-25 11:09:28 -0800667 spin_unlock_irq(&rtc->irq_task_lock);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800668
Jiri Kosina372a3022007-12-04 23:45:05 -0800669 clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
Alessandro Zummod691eb92007-10-16 01:28:15 -0700670
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800671 return retval;
672}
673EXPORT_SYMBOL_GPL(rtc_irq_register);
674
David Brownellab6a2d72007-05-08 00:33:30 -0700675void rtc_irq_unregister(struct rtc_device *rtc, struct rtc_task *task)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800676{
David Brownelld728b1e2006-11-25 11:09:28 -0800677 spin_lock_irq(&rtc->irq_task_lock);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800678 if (rtc->irq_task == task)
679 rtc->irq_task = NULL;
David Brownelld728b1e2006-11-25 11:09:28 -0800680 spin_unlock_irq(&rtc->irq_task_lock);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800681}
682EXPORT_SYMBOL_GPL(rtc_irq_unregister);
683
Thomas Gleixner3c8bb902011-07-22 09:12:51 +0000684static int rtc_update_hrtimer(struct rtc_device *rtc, int enabled)
685{
686 /*
687 * We always cancel the timer here first, because otherwise
688 * we could run into BUG_ON(timer->state != HRTIMER_STATE_CALLBACK);
689 * when we manage to start the timer before the callback
690 * returns HRTIMER_RESTART.
691 *
692 * We cannot use hrtimer_cancel() here as a running callback
693 * could be blocked on rtc->irq_task_lock and hrtimer_cancel()
694 * would spin forever.
695 */
696 if (hrtimer_try_to_cancel(&rtc->pie_timer) < 0)
697 return -1;
698
699 if (enabled) {
700 ktime_t period = ktime_set(0, NSEC_PER_SEC / rtc->irq_freq);
701
702 hrtimer_start(&rtc->pie_timer, period, HRTIMER_MODE_REL);
703 }
704 return 0;
705}
706
David Brownell97144c62007-10-16 01:28:16 -0700707/**
708 * rtc_irq_set_state - enable/disable 2^N Hz periodic IRQs
709 * @rtc: the rtc device
710 * @task: currently registered with rtc_irq_register()
711 * @enabled: true to enable periodic IRQs
712 * Context: any
713 *
714 * Note that rtc_irq_set_freq() should previously have been used to
715 * specify the desired frequency of periodic IRQ task->func() callbacks.
716 */
David Brownellab6a2d72007-05-08 00:33:30 -0700717int rtc_irq_set_state(struct rtc_device *rtc, struct rtc_task *task, int enabled)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800718{
719 int err = 0;
720 unsigned long flags;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800721
Thomas Gleixner3c8bb902011-07-22 09:12:51 +0000722retry:
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800723 spin_lock_irqsave(&rtc->irq_task_lock, flags);
Alessandro Zummod691eb92007-10-16 01:28:15 -0700724 if (rtc->irq_task != NULL && task == NULL)
725 err = -EBUSY;
Chris Brand0734e272013-07-03 15:07:57 -0700726 else if (rtc->irq_task != task)
Alessandro Zummod691eb92007-10-16 01:28:15 -0700727 err = -EACCES;
Chris Brand0734e272013-07-03 15:07:57 -0700728 else {
Thomas Gleixner3c8bb902011-07-22 09:12:51 +0000729 if (rtc_update_hrtimer(rtc, enabled) < 0) {
730 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
731 cpu_relax();
732 goto retry;
733 }
734 rtc->pie_enabled = enabled;
John Stultz6610e082010-09-23 15:07:34 -0700735 }
John Stultz6610e082010-09-23 15:07:34 -0700736 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800737 return err;
738}
739EXPORT_SYMBOL_GPL(rtc_irq_set_state);
740
David Brownell97144c62007-10-16 01:28:16 -0700741/**
742 * rtc_irq_set_freq - set 2^N Hz periodic IRQ frequency for IRQ
743 * @rtc: the rtc device
744 * @task: currently registered with rtc_irq_register()
745 * @freq: positive frequency with which task->func() will be called
746 * Context: any
747 *
748 * Note that rtc_irq_set_state() is used to enable or disable the
749 * periodic IRQs.
750 */
David Brownellab6a2d72007-05-08 00:33:30 -0700751int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800752{
Alessandro Zummo56f10c62006-06-25 05:48:20 -0700753 int err = 0;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800754 unsigned long flags;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800755
Thomas Gleixner6e7a3332011-07-22 09:12:51 +0000756 if (freq <= 0 || freq > RTC_MAX_FREQ)
Marcelo Roberto Jimenez83a06bf2011-02-02 16:04:02 -0200757 return -EINVAL;
Thomas Gleixner3c8bb902011-07-22 09:12:51 +0000758retry:
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800759 spin_lock_irqsave(&rtc->irq_task_lock, flags);
Alessandro Zummod691eb92007-10-16 01:28:15 -0700760 if (rtc->irq_task != NULL && task == NULL)
761 err = -EBUSY;
Chris Brand0734e272013-07-03 15:07:57 -0700762 else if (rtc->irq_task != task)
Alessandro Zummod691eb92007-10-16 01:28:15 -0700763 err = -EACCES;
Chris Brand0734e272013-07-03 15:07:57 -0700764 else {
John Stultz6610e082010-09-23 15:07:34 -0700765 rtc->irq_freq = freq;
Thomas Gleixner3c8bb902011-07-22 09:12:51 +0000766 if (rtc->pie_enabled && rtc_update_hrtimer(rtc, 1) < 0) {
767 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
768 cpu_relax();
769 goto retry;
John Stultz6610e082010-09-23 15:07:34 -0700770 }
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800771 }
John Stultz6610e082010-09-23 15:07:34 -0700772 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800773 return err;
774}
David Brownell2601a462006-11-25 11:09:27 -0800775EXPORT_SYMBOL_GPL(rtc_irq_set_freq);
John Stultz6610e082010-09-23 15:07:34 -0700776
777/**
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100778 * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue
John Stultz6610e082010-09-23 15:07:34 -0700779 * @rtc rtc device
780 * @timer timer being added.
781 *
782 * Enqueues a timer onto the rtc devices timerqueue and sets
783 * the next alarm event appropriately.
784 *
John Stultzaa0be0f2011-01-20 15:26:12 -0800785 * Sets the enabled bit on the added timer.
786 *
John Stultz6610e082010-09-23 15:07:34 -0700787 * Must hold ops_lock for proper serialization of timerqueue
788 */
John Stultzaa0be0f2011-01-20 15:26:12 -0800789static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer)
John Stultz6610e082010-09-23 15:07:34 -0700790{
John Stultzaa0be0f2011-01-20 15:26:12 -0800791 timer->enabled = 1;
John Stultz6610e082010-09-23 15:07:34 -0700792 timerqueue_add(&rtc->timerqueue, &timer->node);
793 if (&timer->node == timerqueue_getnext(&rtc->timerqueue)) {
794 struct rtc_wkalrm alarm;
795 int err;
796 alarm.time = rtc_ktime_to_tm(timer->node.expires);
797 alarm.enabled = 1;
798 err = __rtc_set_alarm(rtc, &alarm);
Zoran Markovic14d0e342013-06-26 16:09:13 -0700799 if (err == -ETIME) {
800 pm_stay_awake(rtc->dev.parent);
John Stultz6610e082010-09-23 15:07:34 -0700801 schedule_work(&rtc->irqwork);
Zoran Markovic14d0e342013-06-26 16:09:13 -0700802 } else if (err) {
John Stultzaa0be0f2011-01-20 15:26:12 -0800803 timerqueue_del(&rtc->timerqueue, &timer->node);
804 timer->enabled = 0;
805 return err;
806 }
John Stultz6610e082010-09-23 15:07:34 -0700807 }
John Stultzaa0be0f2011-01-20 15:26:12 -0800808 return 0;
John Stultz6610e082010-09-23 15:07:34 -0700809}
810
Rabin Vincent41c7f742011-11-22 11:03:14 +0100811static void rtc_alarm_disable(struct rtc_device *rtc)
812{
813 if (!rtc->ops || !rtc->ops->alarm_irq_enable)
814 return;
815
816 rtc->ops->alarm_irq_enable(rtc->dev.parent, false);
817}
818
John Stultz6610e082010-09-23 15:07:34 -0700819/**
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100820 * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue
John Stultz6610e082010-09-23 15:07:34 -0700821 * @rtc rtc device
822 * @timer timer being removed.
823 *
824 * Removes a timer onto the rtc devices timerqueue and sets
825 * the next alarm event appropriately.
826 *
John Stultzaa0be0f2011-01-20 15:26:12 -0800827 * Clears the enabled bit on the removed timer.
828 *
John Stultz6610e082010-09-23 15:07:34 -0700829 * Must hold ops_lock for proper serialization of timerqueue
830 */
John Stultzaa0be0f2011-01-20 15:26:12 -0800831static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer)
John Stultz6610e082010-09-23 15:07:34 -0700832{
833 struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue);
834 timerqueue_del(&rtc->timerqueue, &timer->node);
John Stultzaa0be0f2011-01-20 15:26:12 -0800835 timer->enabled = 0;
John Stultz6610e082010-09-23 15:07:34 -0700836 if (next == &timer->node) {
837 struct rtc_wkalrm alarm;
838 int err;
839 next = timerqueue_getnext(&rtc->timerqueue);
Rabin Vincent41c7f742011-11-22 11:03:14 +0100840 if (!next) {
841 rtc_alarm_disable(rtc);
John Stultz6610e082010-09-23 15:07:34 -0700842 return;
Rabin Vincent41c7f742011-11-22 11:03:14 +0100843 }
John Stultz6610e082010-09-23 15:07:34 -0700844 alarm.time = rtc_ktime_to_tm(next->expires);
845 alarm.enabled = 1;
846 err = __rtc_set_alarm(rtc, &alarm);
Zoran Markovic14d0e342013-06-26 16:09:13 -0700847 if (err == -ETIME) {
848 pm_stay_awake(rtc->dev.parent);
John Stultz6610e082010-09-23 15:07:34 -0700849 schedule_work(&rtc->irqwork);
Zoran Markovic14d0e342013-06-26 16:09:13 -0700850 }
John Stultz6610e082010-09-23 15:07:34 -0700851 }
852}
853
854/**
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100855 * rtc_timer_do_work - Expires rtc timers
John Stultz6610e082010-09-23 15:07:34 -0700856 * @rtc rtc device
857 * @timer timer being removed.
858 *
859 * Expires rtc timers. Reprograms next alarm event if needed.
860 * Called via worktask.
861 *
862 * Serializes access to timerqueue via ops_lock mutex
863 */
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100864void rtc_timer_do_work(struct work_struct *work)
John Stultz6610e082010-09-23 15:07:34 -0700865{
866 struct rtc_timer *timer;
867 struct timerqueue_node *next;
868 ktime_t now;
869 struct rtc_time tm;
870
871 struct rtc_device *rtc =
872 container_of(work, struct rtc_device, irqwork);
873
874 mutex_lock(&rtc->ops_lock);
875again:
876 __rtc_read_time(rtc, &tm);
877 now = rtc_tm_to_ktime(tm);
878 while ((next = timerqueue_getnext(&rtc->timerqueue))) {
879 if (next->expires.tv64 > now.tv64)
880 break;
881
882 /* expire timer */
883 timer = container_of(next, struct rtc_timer, node);
884 timerqueue_del(&rtc->timerqueue, &timer->node);
885 timer->enabled = 0;
886 if (timer->task.func)
887 timer->task.func(timer->task.private_data);
888
889 /* Re-add/fwd periodic timers */
890 if (ktime_to_ns(timer->period)) {
891 timer->node.expires = ktime_add(timer->node.expires,
892 timer->period);
893 timer->enabled = 1;
894 timerqueue_add(&rtc->timerqueue, &timer->node);
895 }
896 }
897
898 /* Set next alarm */
899 if (next) {
900 struct rtc_wkalrm alarm;
901 int err;
Xunlei Pang6528b882014-12-10 15:54:26 -0800902 int retry = 3;
903
John Stultz6610e082010-09-23 15:07:34 -0700904 alarm.time = rtc_ktime_to_tm(next->expires);
905 alarm.enabled = 1;
Xunlei Pang6528b882014-12-10 15:54:26 -0800906reprogram:
John Stultz6610e082010-09-23 15:07:34 -0700907 err = __rtc_set_alarm(rtc, &alarm);
908 if (err == -ETIME)
909 goto again;
Xunlei Pang6528b882014-12-10 15:54:26 -0800910 else if (err) {
911 if (retry-- > 0)
912 goto reprogram;
913
914 timer = container_of(next, struct rtc_timer, node);
915 timerqueue_del(&rtc->timerqueue, &timer->node);
916 timer->enabled = 0;
917 dev_err(&rtc->dev, "__rtc_set_alarm: err=%d\n", err);
918 goto again;
919 }
Rabin Vincent41c7f742011-11-22 11:03:14 +0100920 } else
921 rtc_alarm_disable(rtc);
John Stultz6610e082010-09-23 15:07:34 -0700922
Zoran Markovic14d0e342013-06-26 16:09:13 -0700923 pm_relax(rtc->dev.parent);
John Stultz6610e082010-09-23 15:07:34 -0700924 mutex_unlock(&rtc->ops_lock);
925}
926
927
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100928/* rtc_timer_init - Initializes an rtc_timer
John Stultz6610e082010-09-23 15:07:34 -0700929 * @timer: timer to be intiialized
930 * @f: function pointer to be called when timer fires
931 * @data: private data passed to function pointer
932 *
933 * Kernel interface to initializing an rtc_timer.
934 */
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700935void rtc_timer_init(struct rtc_timer *timer, void (*f)(void *p), void *data)
John Stultz6610e082010-09-23 15:07:34 -0700936{
937 timerqueue_init(&timer->node);
938 timer->enabled = 0;
939 timer->task.func = f;
940 timer->task.private_data = data;
941}
942
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100943/* rtc_timer_start - Sets an rtc_timer to fire in the future
John Stultz6610e082010-09-23 15:07:34 -0700944 * @ rtc: rtc device to be used
945 * @ timer: timer being set
946 * @ expires: time at which to expire the timer
947 * @ period: period that the timer will recur
948 *
949 * Kernel interface to set an rtc_timer
950 */
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700951int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer *timer,
John Stultz6610e082010-09-23 15:07:34 -0700952 ktime_t expires, ktime_t period)
953{
954 int ret = 0;
955 mutex_lock(&rtc->ops_lock);
956 if (timer->enabled)
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100957 rtc_timer_remove(rtc, timer);
John Stultz6610e082010-09-23 15:07:34 -0700958
959 timer->node.expires = expires;
960 timer->period = period;
961
John Stultzaa0be0f2011-01-20 15:26:12 -0800962 ret = rtc_timer_enqueue(rtc, timer);
John Stultz6610e082010-09-23 15:07:34 -0700963
964 mutex_unlock(&rtc->ops_lock);
965 return ret;
966}
967
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100968/* rtc_timer_cancel - Stops an rtc_timer
John Stultz6610e082010-09-23 15:07:34 -0700969 * @ rtc: rtc device to be used
970 * @ timer: timer being set
971 *
972 * Kernel interface to cancel an rtc_timer
973 */
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700974int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer *timer)
John Stultz6610e082010-09-23 15:07:34 -0700975{
976 int ret = 0;
977 mutex_lock(&rtc->ops_lock);
978 if (timer->enabled)
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100979 rtc_timer_remove(rtc, timer);
John Stultz6610e082010-09-23 15:07:34 -0700980 mutex_unlock(&rtc->ops_lock);
981 return ret;
982}
983
984