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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
Baolin Wang29a1f592017-12-14 13:31:43 +080020#define CREATE_TRACE_POINTS
21#include <trace/events/rtc.h>
22
John Stultzaa0be0f2011-01-20 15:26:12 -080023static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer);
24static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer);
25
Baolin Wang98951562018-01-08 14:04:50 +080026static void rtc_add_offset(struct rtc_device *rtc, struct rtc_time *tm)
27{
28 time64_t secs;
29
30 if (!rtc->offset_secs)
31 return;
32
33 secs = rtc_tm_to_time64(tm);
34
35 /*
36 * Since the reading time values from RTC device are always in the RTC
37 * original valid range, but we need to skip the overlapped region
38 * between expanded range and original range, which is no need to add
39 * the offset.
40 */
41 if ((rtc->start_secs > rtc->range_min && secs >= rtc->start_secs) ||
42 (rtc->start_secs < rtc->range_min &&
43 secs <= (rtc->start_secs + rtc->range_max - rtc->range_min)))
44 return;
45
46 rtc_time64_to_tm(secs + rtc->offset_secs, tm);
47}
48
49static void rtc_subtract_offset(struct rtc_device *rtc, struct rtc_time *tm)
50{
51 time64_t secs;
52
53 if (!rtc->offset_secs)
54 return;
55
56 secs = rtc_tm_to_time64(tm);
57
58 /*
59 * If the setting time values are in the valid range of RTC hardware
60 * device, then no need to subtract the offset when setting time to RTC
61 * device. Otherwise we need to subtract the offset to make the time
62 * values are valid for RTC hardware device.
63 */
64 if (secs >= rtc->range_min && secs <= rtc->range_max)
65 return;
66
67 rtc_time64_to_tm(secs - rtc->offset_secs, tm);
68}
69
Baolin Wang4c4e5df2018-01-08 14:04:49 +080070static int rtc_valid_range(struct rtc_device *rtc, struct rtc_time *tm)
71{
72 if (rtc->range_min != rtc->range_max) {
73 time64_t time = rtc_tm_to_time64(tm);
Baolin Wang98951562018-01-08 14:04:50 +080074 time64_t range_min = rtc->set_start_time ? rtc->start_secs :
75 rtc->range_min;
76 time64_t range_max = rtc->set_start_time ?
77 (rtc->start_secs + rtc->range_max - rtc->range_min) :
78 rtc->range_max;
Baolin Wang4c4e5df2018-01-08 14:04:49 +080079
Baolin Wang98951562018-01-08 14:04:50 +080080 if (time < range_min || time > range_max)
Baolin Wang4c4e5df2018-01-08 14:04:49 +080081 return -ERANGE;
82 }
83
84 return 0;
85}
86
John Stultz6610e082010-09-23 15:07:34 -070087static int __rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
88{
89 int err;
90 if (!rtc->ops)
91 err = -ENODEV;
92 else if (!rtc->ops->read_time)
93 err = -EINVAL;
94 else {
95 memset(tm, 0, sizeof(struct rtc_time));
96 err = rtc->ops->read_time(rtc->dev.parent, tm);
Hyogi Gim16682c862014-12-10 15:52:27 -080097 if (err < 0) {
Aaro Koskinend0bddb52015-04-16 12:45:51 -070098 dev_dbg(&rtc->dev, "read_time: fail to read: %d\n",
99 err);
Hyogi Gim16682c862014-12-10 15:52:27 -0800100 return err;
101 }
102
Baolin Wang98951562018-01-08 14:04:50 +0800103 rtc_add_offset(rtc, tm);
104
Hyogi Gim16682c862014-12-10 15:52:27 -0800105 err = rtc_valid_tm(tm);
106 if (err < 0)
Aaro Koskinend0bddb52015-04-16 12:45:51 -0700107 dev_dbg(&rtc->dev, "read_time: rtc_time isn't valid\n");
John Stultz6610e082010-09-23 15:07:34 -0700108 }
109 return err;
110}
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800111
David Brownellab6a2d72007-05-08 00:33:30 -0700112int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800113{
114 int err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800115
116 err = mutex_lock_interruptible(&rtc->ops_lock);
117 if (err)
David Brownellb68bb262008-07-29 22:33:30 -0700118 return err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800119
John Stultz6610e082010-09-23 15:07:34 -0700120 err = __rtc_read_time(rtc, tm);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800121 mutex_unlock(&rtc->ops_lock);
Baolin Wang29a1f592017-12-14 13:31:43 +0800122
123 trace_rtc_read_time(rtc_tm_to_time64(tm), err);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800124 return err;
125}
126EXPORT_SYMBOL_GPL(rtc_read_time);
127
David Brownellab6a2d72007-05-08 00:33:30 -0700128int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800129{
130 int err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800131
132 err = rtc_valid_tm(tm);
133 if (err != 0)
134 return err;
135
Baolin Wang4c4e5df2018-01-08 14:04:49 +0800136 err = rtc_valid_range(rtc, tm);
137 if (err)
138 return err;
Alexandre Belloni71db0492018-02-17 14:58:40 +0100139
Baolin Wang98951562018-01-08 14:04:50 +0800140 rtc_subtract_offset(rtc, tm);
141
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800142 err = mutex_lock_interruptible(&rtc->ops_lock);
143 if (err)
David Brownellb68bb262008-07-29 22:33:30 -0700144 return err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800145
146 if (!rtc->ops)
147 err = -ENODEV;
Alessandro Zummobbccf832009-01-06 14:42:21 -0800148 else if (rtc->ops->set_time)
David Brownellcd966202007-05-08 00:33:40 -0700149 err = rtc->ops->set_time(rtc->dev.parent, tm);
Xunlei Pang8e4ff1a2015-04-01 20:34:27 -0700150 else if (rtc->ops->set_mmss64) {
151 time64_t secs64 = rtc_tm_to_time64(tm);
152
153 err = rtc->ops->set_mmss64(rtc->dev.parent, secs64);
154 } else if (rtc->ops->set_mmss) {
Xunlei Pangbc10aa92015-01-22 02:31:51 +0000155 time64_t secs64 = rtc_tm_to_time64(tm);
156 err = rtc->ops->set_mmss(rtc->dev.parent, secs64);
Alessandro Zummobbccf832009-01-06 14:42:21 -0800157 } else
158 err = -EINVAL;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800159
Zoran Markovic14d0e342013-06-26 16:09:13 -0700160 pm_stay_awake(rtc->dev.parent);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800161 mutex_unlock(&rtc->ops_lock);
NeilBrown5f9679d2011-12-09 09:39:15 +1100162 /* A timer might have just expired */
163 schedule_work(&rtc->irqwork);
Baolin Wang29a1f592017-12-14 13:31:43 +0800164
165 trace_rtc_set_time(rtc_tm_to_time64(tm), err);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800166 return err;
167}
168EXPORT_SYMBOL_GPL(rtc_set_time);
169
John Stultzf44f7f92011-02-21 22:58:51 -0800170static int rtc_read_alarm_internal(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
171{
172 int err;
173
174 err = mutex_lock_interruptible(&rtc->ops_lock);
175 if (err)
176 return err;
177
178 if (rtc->ops == NULL)
179 err = -ENODEV;
180 else if (!rtc->ops->read_alarm)
181 err = -EINVAL;
182 else {
Uwe Kleine-Königd68778b2016-05-11 09:11:23 +0200183 alarm->enabled = 0;
184 alarm->pending = 0;
185 alarm->time.tm_sec = -1;
186 alarm->time.tm_min = -1;
187 alarm->time.tm_hour = -1;
188 alarm->time.tm_mday = -1;
189 alarm->time.tm_mon = -1;
190 alarm->time.tm_year = -1;
191 alarm->time.tm_wday = -1;
192 alarm->time.tm_yday = -1;
193 alarm->time.tm_isdst = -1;
John Stultzf44f7f92011-02-21 22:58:51 -0800194 err = rtc->ops->read_alarm(rtc->dev.parent, alarm);
195 }
196
197 mutex_unlock(&rtc->ops_lock);
Baolin Wang29a1f592017-12-14 13:31:43 +0800198
199 trace_rtc_read_alarm(rtc_tm_to_time64(&alarm->time), err);
John Stultzf44f7f92011-02-21 22:58:51 -0800200 return err;
201}
202
203int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
204{
205 int err;
206 struct rtc_time before, now;
207 int first_time = 1;
Xunlei Pangbc10aa92015-01-22 02:31:51 +0000208 time64_t t_now, t_alm;
John Stultzf44f7f92011-02-21 22:58:51 -0800209 enum { none, day, month, year } missing = none;
210 unsigned days;
211
212 /* The lower level RTC driver may return -1 in some fields,
213 * creating invalid alarm->time values, for reasons like:
214 *
215 * - The hardware may not be capable of filling them in;
216 * many alarms match only on time-of-day fields, not
217 * day/month/year calendar data.
218 *
219 * - Some hardware uses illegal values as "wildcard" match
220 * values, which non-Linux firmware (like a BIOS) may try
221 * to set up as e.g. "alarm 15 minutes after each hour".
222 * Linux uses only oneshot alarms.
223 *
224 * When we see that here, we deal with it by using values from
225 * a current RTC timestamp for any missing (-1) values. The
226 * RTC driver prevents "periodic alarm" modes.
227 *
228 * But this can be racey, because some fields of the RTC timestamp
229 * may have wrapped in the interval since we read the RTC alarm,
230 * which would lead to us inserting inconsistent values in place
231 * of the -1 fields.
232 *
233 * Reading the alarm and timestamp in the reverse sequence
234 * would have the same race condition, and not solve the issue.
235 *
236 * So, we must first read the RTC timestamp,
237 * then read the RTC alarm value,
238 * and then read a second RTC timestamp.
239 *
240 * If any fields of the second timestamp have changed
241 * when compared with the first timestamp, then we know
242 * our timestamp may be inconsistent with that used by
243 * the low-level rtc_read_alarm_internal() function.
244 *
245 * So, when the two timestamps disagree, we just loop and do
246 * the process again to get a fully consistent set of values.
247 *
248 * This could all instead be done in the lower level driver,
249 * but since more than one lower level RTC implementation needs it,
250 * then it's probably best best to do it here instead of there..
251 */
252
253 /* Get the "before" timestamp */
254 err = rtc_read_time(rtc, &before);
255 if (err < 0)
256 return err;
257 do {
258 if (!first_time)
259 memcpy(&before, &now, sizeof(struct rtc_time));
260 first_time = 0;
261
262 /* get the RTC alarm values, which may be incomplete */
263 err = rtc_read_alarm_internal(rtc, alarm);
264 if (err)
265 return err;
266
267 /* full-function RTCs won't have such missing fields */
Alexandre Bellonifd6792b2018-07-12 12:22:44 +0200268 if (rtc_valid_tm(&alarm->time) == 0) {
269 rtc_add_offset(rtc, &alarm->time);
John Stultzf44f7f92011-02-21 22:58:51 -0800270 return 0;
Alexandre Bellonifd6792b2018-07-12 12:22:44 +0200271 }
John Stultzf44f7f92011-02-21 22:58:51 -0800272
273 /* get the "after" timestamp, to detect wrapped fields */
274 err = rtc_read_time(rtc, &now);
275 if (err < 0)
276 return err;
277
278 /* note that tm_sec is a "don't care" value here: */
279 } while ( before.tm_min != now.tm_min
280 || before.tm_hour != now.tm_hour
281 || before.tm_mon != now.tm_mon
282 || before.tm_year != now.tm_year);
283
284 /* Fill in the missing alarm fields using the timestamp; we
285 * know there's at least one since alarm->time is invalid.
286 */
287 if (alarm->time.tm_sec == -1)
288 alarm->time.tm_sec = now.tm_sec;
289 if (alarm->time.tm_min == -1)
290 alarm->time.tm_min = now.tm_min;
291 if (alarm->time.tm_hour == -1)
292 alarm->time.tm_hour = now.tm_hour;
293
294 /* For simplicity, only support date rollover for now */
Ben Hutchingse74a8f22012-01-10 15:11:02 -0800295 if (alarm->time.tm_mday < 1 || alarm->time.tm_mday > 31) {
John Stultzf44f7f92011-02-21 22:58:51 -0800296 alarm->time.tm_mday = now.tm_mday;
297 missing = day;
298 }
Ben Hutchingse74a8f22012-01-10 15:11:02 -0800299 if ((unsigned)alarm->time.tm_mon >= 12) {
John Stultzf44f7f92011-02-21 22:58:51 -0800300 alarm->time.tm_mon = now.tm_mon;
301 if (missing == none)
302 missing = month;
303 }
304 if (alarm->time.tm_year == -1) {
305 alarm->time.tm_year = now.tm_year;
306 if (missing == none)
307 missing = year;
308 }
309
Vaibhav Jainda96aea2017-05-19 22:18:55 +0530310 /* Can't proceed if alarm is still invalid after replacing
311 * missing fields.
312 */
313 err = rtc_valid_tm(&alarm->time);
314 if (err)
315 goto done;
316
John Stultzf44f7f92011-02-21 22:58:51 -0800317 /* with luck, no rollover is needed */
Xunlei Pangbc10aa92015-01-22 02:31:51 +0000318 t_now = rtc_tm_to_time64(&now);
319 t_alm = rtc_tm_to_time64(&alarm->time);
John Stultzf44f7f92011-02-21 22:58:51 -0800320 if (t_now < t_alm)
321 goto done;
322
323 switch (missing) {
324
325 /* 24 hour rollover ... if it's now 10am Monday, an alarm that
326 * that will trigger at 5am will do so at 5am Tuesday, which
327 * could also be in the next month or year. This is a common
328 * case, especially for PCs.
329 */
330 case day:
331 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "day");
332 t_alm += 24 * 60 * 60;
Xunlei Pangbc10aa92015-01-22 02:31:51 +0000333 rtc_time64_to_tm(t_alm, &alarm->time);
John Stultzf44f7f92011-02-21 22:58:51 -0800334 break;
335
336 /* Month rollover ... if it's the 31th, an alarm on the 3rd will
337 * be next month. An alarm matching on the 30th, 29th, or 28th
338 * may end up in the month after that! Many newer PCs support
339 * this type of alarm.
340 */
341 case month:
342 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "month");
343 do {
344 if (alarm->time.tm_mon < 11)
345 alarm->time.tm_mon++;
346 else {
347 alarm->time.tm_mon = 0;
348 alarm->time.tm_year++;
349 }
350 days = rtc_month_days(alarm->time.tm_mon,
351 alarm->time.tm_year);
352 } while (days < alarm->time.tm_mday);
353 break;
354
355 /* Year rollover ... easy except for leap years! */
356 case year:
357 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "year");
358 do {
359 alarm->time.tm_year++;
Ales Novakee1d9012014-06-06 14:35:39 -0700360 } while (!is_leap_year(alarm->time.tm_year + 1900)
361 && rtc_valid_tm(&alarm->time) != 0);
John Stultzf44f7f92011-02-21 22:58:51 -0800362 break;
363
364 default:
365 dev_warn(&rtc->dev, "alarm rollover not handled\n");
366 }
367
Ales Novakee1d9012014-06-06 14:35:39 -0700368 err = rtc_valid_tm(&alarm->time);
369
Vaibhav Jainda96aea2017-05-19 22:18:55 +0530370done:
Ales Novakee1d9012014-06-06 14:35:39 -0700371 if (err) {
372 dev_warn(&rtc->dev, "invalid alarm value: %d-%d-%d %d:%d:%d\n",
373 alarm->time.tm_year + 1900, alarm->time.tm_mon + 1,
374 alarm->time.tm_mday, alarm->time.tm_hour, alarm->time.tm_min,
375 alarm->time.tm_sec);
376 }
377
378 return err;
John Stultzf44f7f92011-02-21 22:58:51 -0800379}
380
John Stultz6610e082010-09-23 15:07:34 -0700381int rtc_read_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
385 err = mutex_lock_interruptible(&rtc->ops_lock);
386 if (err)
David Brownellb68bb262008-07-29 22:33:30 -0700387 return err;
John Stultzd5553a52011-01-20 15:26:13 -0800388 if (rtc->ops == NULL)
389 err = -ENODEV;
390 else if (!rtc->ops->read_alarm)
391 err = -EINVAL;
392 else {
393 memset(alarm, 0, sizeof(struct rtc_wkalrm));
394 alarm->enabled = rtc->aie_timer.enabled;
John Stultz6610e082010-09-23 15:07:34 -0700395 alarm->time = rtc_ktime_to_tm(rtc->aie_timer.node.expires);
John Stultzd5553a52011-01-20 15:26:13 -0800396 }
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800397 mutex_unlock(&rtc->ops_lock);
Mark Lord0e36a9a2007-10-16 01:28:21 -0700398
Baolin Wang29a1f592017-12-14 13:31:43 +0800399 trace_rtc_read_alarm(rtc_tm_to_time64(&alarm->time), err);
John Stultzd5553a52011-01-20 15:26:13 -0800400 return err;
Mark Lord0e36a9a2007-10-16 01:28:21 -0700401}
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800402EXPORT_SYMBOL_GPL(rtc_read_alarm);
403
Mark Brownd576fe42011-06-01 11:13:16 +0100404static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
John Stultz6610e082010-09-23 15:07:34 -0700405{
406 struct rtc_time tm;
Xunlei Pangbc10aa92015-01-22 02:31:51 +0000407 time64_t now, scheduled;
John Stultz6610e082010-09-23 15:07:34 -0700408 int err;
409
410 err = rtc_valid_tm(&alarm->time);
411 if (err)
412 return err;
Baolin Wang98951562018-01-08 14:04:50 +0800413
Xunlei Pangbc10aa92015-01-22 02:31:51 +0000414 scheduled = rtc_tm_to_time64(&alarm->time);
John Stultz6610e082010-09-23 15:07:34 -0700415
416 /* Make sure we're not setting alarms in the past */
417 err = __rtc_read_time(rtc, &tm);
Hyogi Gimca6dc2d2014-08-08 14:20:11 -0700418 if (err)
419 return err;
Xunlei Pangbc10aa92015-01-22 02:31:51 +0000420 now = rtc_tm_to_time64(&tm);
John Stultz6610e082010-09-23 15:07:34 -0700421 if (scheduled <= now)
422 return -ETIME;
423 /*
424 * XXX - We just checked to make sure the alarm time is not
425 * in the past, but there is still a race window where if
426 * the is alarm set for the next second and the second ticks
427 * over right here, before we set the alarm.
428 */
429
Alexandre Bellonifd6792b2018-07-12 12:22:44 +0200430 rtc_subtract_offset(rtc, &alarm->time);
431
Linus Torvalds157e8bf2012-01-03 17:32:13 -0800432 if (!rtc->ops)
433 err = -ENODEV;
434 else if (!rtc->ops->set_alarm)
435 err = -EINVAL;
436 else
437 err = rtc->ops->set_alarm(rtc->dev.parent, alarm);
438
Baolin Wang29a1f592017-12-14 13:31:43 +0800439 trace_rtc_set_alarm(rtc_tm_to_time64(&alarm->time), err);
Linus Torvalds157e8bf2012-01-03 17:32:13 -0800440 return err;
John Stultz6610e082010-09-23 15:07:34 -0700441}
442
David Brownellab6a2d72007-05-08 00:33:30 -0700443int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800444{
445 int err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800446
Alexandre Belloniabfdff42018-06-05 23:09:14 +0200447 if (!rtc->ops)
448 return -ENODEV;
449 else if (!rtc->ops->set_alarm)
450 return -EINVAL;
451
David Brownellf8245c22007-05-08 00:34:07 -0700452 err = rtc_valid_tm(&alarm->time);
453 if (err != 0)
454 return err;
455
Baolin Wang4c4e5df2018-01-08 14:04:49 +0800456 err = rtc_valid_range(rtc, &alarm->time);
457 if (err)
458 return err;
Alexandre Belloni71db0492018-02-17 14:58:40 +0100459
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800460 err = mutex_lock_interruptible(&rtc->ops_lock);
461 if (err)
David Brownellb68bb262008-07-29 22:33:30 -0700462 return err;
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700463 if (rtc->aie_timer.enabled)
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100464 rtc_timer_remove(rtc, &rtc->aie_timer);
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700465
John Stultz6610e082010-09-23 15:07:34 -0700466 rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
Thomas Gleixner8b0e1952016-12-25 12:30:41 +0100467 rtc->aie_timer.period = 0;
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700468 if (alarm->enabled)
John Stultzaa0be0f2011-01-20 15:26:12 -0800469 err = rtc_timer_enqueue(rtc, &rtc->aie_timer);
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700470
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800471 mutex_unlock(&rtc->ops_lock);
Baolin Wang98951562018-01-08 14:04:50 +0800472
John Stultzaa0be0f2011-01-20 15:26:12 -0800473 return err;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800474}
475EXPORT_SYMBOL_GPL(rtc_set_alarm);
476
John Stultzf6d5b332011-03-29 18:00:27 -0700477/* Called once per device from rtc_device_register */
478int rtc_initialize_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
479{
480 int err;
John Stultzbd729d72012-01-05 15:21:19 -0800481 struct rtc_time now;
John Stultzf6d5b332011-03-29 18:00:27 -0700482
483 err = rtc_valid_tm(&alarm->time);
484 if (err != 0)
485 return err;
486
John Stultzbd729d72012-01-05 15:21:19 -0800487 err = rtc_read_time(rtc, &now);
488 if (err)
489 return err;
490
John Stultzf6d5b332011-03-29 18:00:27 -0700491 err = mutex_lock_interruptible(&rtc->ops_lock);
492 if (err)
493 return err;
494
495 rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
Thomas Gleixner8b0e1952016-12-25 12:30:41 +0100496 rtc->aie_timer.period = 0;
John Stultzbd729d72012-01-05 15:21:19 -0800497
Uwe Kleine-König6785b3b2016-07-02 17:28:12 +0200498 /* Alarm has to be enabled & in the future for us to enqueue it */
Thomas Gleixner2456e852016-12-25 11:38:40 +0100499 if (alarm->enabled && (rtc_tm_to_ktime(now) <
500 rtc->aie_timer.node.expires)) {
John Stultzbd729d72012-01-05 15:21:19 -0800501
John Stultzf6d5b332011-03-29 18:00:27 -0700502 rtc->aie_timer.enabled = 1;
503 timerqueue_add(&rtc->timerqueue, &rtc->aie_timer.node);
Baolin Wang29a1f592017-12-14 13:31:43 +0800504 trace_rtc_timer_enqueue(&rtc->aie_timer);
John Stultzf6d5b332011-03-29 18:00:27 -0700505 }
506 mutex_unlock(&rtc->ops_lock);
507 return err;
508}
509EXPORT_SYMBOL_GPL(rtc_initialize_alarm);
510
Alessandro Zummo099e6572009-01-04 12:00:54 -0800511int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled)
512{
513 int err = mutex_lock_interruptible(&rtc->ops_lock);
514 if (err)
515 return err;
516
John Stultz6610e082010-09-23 15:07:34 -0700517 if (rtc->aie_timer.enabled != enabled) {
John Stultzaa0be0f2011-01-20 15:26:12 -0800518 if (enabled)
519 err = rtc_timer_enqueue(rtc, &rtc->aie_timer);
520 else
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100521 rtc_timer_remove(rtc, &rtc->aie_timer);
John Stultz6610e082010-09-23 15:07:34 -0700522 }
523
John Stultzaa0be0f2011-01-20 15:26:12 -0800524 if (err)
Uwe Kleine-König516373b2011-02-14 11:33:17 +0100525 /* nothing */;
526 else if (!rtc->ops)
Alessandro Zummo099e6572009-01-04 12:00:54 -0800527 err = -ENODEV;
528 else if (!rtc->ops->alarm_irq_enable)
529 err = -EINVAL;
530 else
531 err = rtc->ops->alarm_irq_enable(rtc->dev.parent, enabled);
532
533 mutex_unlock(&rtc->ops_lock);
Baolin Wang29a1f592017-12-14 13:31:43 +0800534
535 trace_rtc_alarm_irq_enable(enabled, err);
Alessandro Zummo099e6572009-01-04 12:00:54 -0800536 return err;
537}
538EXPORT_SYMBOL_GPL(rtc_alarm_irq_enable);
539
540int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
541{
542 int err = mutex_lock_interruptible(&rtc->ops_lock);
543 if (err)
544 return err;
545
John Stultz456d66e2011-02-11 18:15:23 -0800546#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
547 if (enabled == 0 && rtc->uie_irq_active) {
548 mutex_unlock(&rtc->ops_lock);
549 return rtc_dev_update_irq_enable_emul(rtc, 0);
550 }
551#endif
John Stultz6610e082010-09-23 15:07:34 -0700552 /* make sure we're changing state */
553 if (rtc->uie_rtctimer.enabled == enabled)
554 goto out;
555
John Stultz4a649902012-03-06 17:16:09 -0800556 if (rtc->uie_unsupported) {
557 err = -EINVAL;
558 goto out;
559 }
560
John Stultz6610e082010-09-23 15:07:34 -0700561 if (enabled) {
562 struct rtc_time tm;
563 ktime_t now, onesec;
564
565 __rtc_read_time(rtc, &tm);
566 onesec = ktime_set(1, 0);
567 now = rtc_tm_to_ktime(tm);
568 rtc->uie_rtctimer.node.expires = ktime_add(now, onesec);
569 rtc->uie_rtctimer.period = ktime_set(1, 0);
John Stultzaa0be0f2011-01-20 15:26:12 -0800570 err = rtc_timer_enqueue(rtc, &rtc->uie_rtctimer);
571 } else
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100572 rtc_timer_remove(rtc, &rtc->uie_rtctimer);
Alessandro Zummo099e6572009-01-04 12:00:54 -0800573
John Stultz6610e082010-09-23 15:07:34 -0700574out:
Alessandro Zummo099e6572009-01-04 12:00:54 -0800575 mutex_unlock(&rtc->ops_lock);
John Stultz456d66e2011-02-11 18:15:23 -0800576#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
577 /*
578 * Enable emulation if the driver did not provide
579 * the update_irq_enable function pointer or if returned
580 * -EINVAL to signal that it has been configured without
581 * interrupts or that are not available at the moment.
582 */
583 if (err == -EINVAL)
584 err = rtc_dev_update_irq_enable_emul(rtc, enabled);
585#endif
Alessandro Zummo099e6572009-01-04 12:00:54 -0800586 return err;
John Stultz6610e082010-09-23 15:07:34 -0700587
Alessandro Zummo099e6572009-01-04 12:00:54 -0800588}
589EXPORT_SYMBOL_GPL(rtc_update_irq_enable);
590
John Stultz6610e082010-09-23 15:07:34 -0700591
David Brownelld728b1e2006-11-25 11:09:28 -0800592/**
John Stultz6610e082010-09-23 15:07:34 -0700593 * rtc_handle_legacy_irq - AIE, UIE and PIE event hook
594 * @rtc: pointer to the rtc device
595 *
596 * This function is called when an AIE, UIE or PIE mode interrupt
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300597 * has occurred (or been emulated).
John Stultz6610e082010-09-23 15:07:34 -0700598 *
599 * Triggers the registered irq_task function callback.
600 */
John Stultz456d66e2011-02-11 18:15:23 -0800601void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode)
John Stultz6610e082010-09-23 15:07:34 -0700602{
603 unsigned long flags;
604
605 /* mark one irq of the appropriate mode */
606 spin_lock_irqsave(&rtc->irq_lock, flags);
607 rtc->irq_data = (rtc->irq_data + (num << 8)) | (RTC_IRQF|mode);
608 spin_unlock_irqrestore(&rtc->irq_lock, flags);
609
John Stultz6610e082010-09-23 15:07:34 -0700610 wake_up_interruptible(&rtc->irq_queue);
611 kill_fasync(&rtc->async_queue, SIGIO, POLL_IN);
612}
613
614
615/**
616 * rtc_aie_update_irq - AIE mode rtctimer hook
617 * @private: pointer to the rtc_device
618 *
619 * This functions is called when the aie_timer expires.
620 */
621void rtc_aie_update_irq(void *private)
622{
623 struct rtc_device *rtc = (struct rtc_device *)private;
624 rtc_handle_legacy_irq(rtc, 1, RTC_AF);
625}
626
627
628/**
629 * rtc_uie_update_irq - UIE mode rtctimer hook
630 * @private: pointer to the rtc_device
631 *
632 * This functions is called when the uie_timer expires.
633 */
634void rtc_uie_update_irq(void *private)
635{
636 struct rtc_device *rtc = (struct rtc_device *)private;
637 rtc_handle_legacy_irq(rtc, 1, RTC_UF);
638}
639
640
641/**
642 * rtc_pie_update_irq - PIE mode hrtimer hook
643 * @timer: pointer to the pie mode hrtimer
644 *
645 * This function is used to emulate PIE mode interrupts
646 * using an hrtimer. This function is called when the periodic
647 * hrtimer expires.
648 */
649enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer)
650{
651 struct rtc_device *rtc;
652 ktime_t period;
653 int count;
654 rtc = container_of(timer, struct rtc_device, pie_timer);
655
Thomas Gleixner8b0e1952016-12-25 12:30:41 +0100656 period = NSEC_PER_SEC / rtc->irq_freq;
John Stultz6610e082010-09-23 15:07:34 -0700657 count = hrtimer_forward_now(timer, period);
658
659 rtc_handle_legacy_irq(rtc, count, RTC_PF);
660
661 return HRTIMER_RESTART;
662}
663
664/**
665 * rtc_update_irq - Triggered when a RTC interrupt occurs.
David Brownellab6a2d72007-05-08 00:33:30 -0700666 * @rtc: the rtc device
David Brownelld728b1e2006-11-25 11:09:28 -0800667 * @num: how many irqs are being reported (usually one)
668 * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
Atsushi Nemotoe6229bec2009-06-18 16:49:09 -0700669 * Context: any
David Brownelld728b1e2006-11-25 11:09:28 -0800670 */
David Brownellab6a2d72007-05-08 00:33:30 -0700671void rtc_update_irq(struct rtc_device *rtc,
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800672 unsigned long num, unsigned long events)
673{
viresh kumare7cba882015-07-31 16:23:43 +0530674 if (IS_ERR_OR_NULL(rtc))
Alessandro Zummo131c9cc2014-04-03 14:50:09 -0700675 return;
676
NeilBrown7523cee2012-08-05 22:56:20 +0200677 pm_stay_awake(rtc->dev.parent);
John Stultz6610e082010-09-23 15:07:34 -0700678 schedule_work(&rtc->irqwork);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800679}
680EXPORT_SYMBOL_GPL(rtc_update_irq);
681
Michał Mirosław9f3b7952013-02-01 20:40:17 +0100682static int __rtc_match(struct device *dev, const void *data)
Dave Young71da8902008-01-22 14:00:34 +0800683{
Michał Mirosław9f3b7952013-02-01 20:40:17 +0100684 const char *name = data;
Dave Young71da8902008-01-22 14:00:34 +0800685
Kay Sieversd4afc762009-01-06 14:42:11 -0800686 if (strcmp(dev_name(dev), name) == 0)
Dave Young71da8902008-01-22 14:00:34 +0800687 return 1;
688 return 0;
689}
690
Michał Mirosław9f3b7952013-02-01 20:40:17 +0100691struct rtc_device *rtc_class_open(const char *name)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800692{
David Brownellcd966202007-05-08 00:33:40 -0700693 struct device *dev;
David Brownellab6a2d72007-05-08 00:33:30 -0700694 struct rtc_device *rtc = NULL;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800695
Greg Kroah-Hartman695794a2008-05-22 17:21:08 -0400696 dev = class_find_device(rtc_class, NULL, name, __rtc_match);
Dave Young71da8902008-01-22 14:00:34 +0800697 if (dev)
698 rtc = to_rtc_device(dev);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800699
David Brownellab6a2d72007-05-08 00:33:30 -0700700 if (rtc) {
701 if (!try_module_get(rtc->owner)) {
David Brownellcd966202007-05-08 00:33:40 -0700702 put_device(dev);
David Brownellab6a2d72007-05-08 00:33:30 -0700703 rtc = NULL;
704 }
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800705 }
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800706
David Brownellab6a2d72007-05-08 00:33:30 -0700707 return rtc;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800708}
709EXPORT_SYMBOL_GPL(rtc_class_open);
710
David Brownellab6a2d72007-05-08 00:33:30 -0700711void rtc_class_close(struct rtc_device *rtc)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800712{
David Brownellab6a2d72007-05-08 00:33:30 -0700713 module_put(rtc->owner);
David Brownellcd966202007-05-08 00:33:40 -0700714 put_device(&rtc->dev);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800715}
716EXPORT_SYMBOL_GPL(rtc_class_close);
717
Thomas Gleixner3c8bb902011-07-22 09:12:51 +0000718static int rtc_update_hrtimer(struct rtc_device *rtc, int enabled)
719{
720 /*
721 * We always cancel the timer here first, because otherwise
722 * we could run into BUG_ON(timer->state != HRTIMER_STATE_CALLBACK);
723 * when we manage to start the timer before the callback
724 * returns HRTIMER_RESTART.
725 *
726 * We cannot use hrtimer_cancel() here as a running callback
727 * could be blocked on rtc->irq_task_lock and hrtimer_cancel()
728 * would spin forever.
729 */
730 if (hrtimer_try_to_cancel(&rtc->pie_timer) < 0)
731 return -1;
732
733 if (enabled) {
Thomas Gleixner8b0e1952016-12-25 12:30:41 +0100734 ktime_t period = NSEC_PER_SEC / rtc->irq_freq;
Thomas Gleixner3c8bb902011-07-22 09:12:51 +0000735
736 hrtimer_start(&rtc->pie_timer, period, HRTIMER_MODE_REL);
737 }
738 return 0;
739}
740
David Brownell97144c62007-10-16 01:28:16 -0700741/**
742 * rtc_irq_set_state - enable/disable 2^N Hz periodic IRQs
743 * @rtc: the rtc device
744 * @task: currently registered with rtc_irq_register()
745 * @enabled: true to enable periodic IRQs
746 * Context: any
747 *
748 * Note that rtc_irq_set_freq() should previously have been used to
Alexandre Belloniacecb3a2018-07-25 14:58:10 +0200749 * specify the desired frequency of periodic IRQ.
David Brownell97144c62007-10-16 01:28:16 -0700750 */
Alexandre Belloni8719d3c2018-07-25 15:07:09 +0200751int rtc_irq_set_state(struct rtc_device *rtc, int enabled)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800752{
753 int err = 0;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800754
Alexandre Belloniacecb3a2018-07-25 14:58:10 +0200755 while (rtc_update_hrtimer(rtc, enabled) < 0)
756 cpu_relax();
757
758 rtc->pie_enabled = enabled;
Baolin Wang29a1f592017-12-14 13:31:43 +0800759
760 trace_rtc_irq_set_state(enabled, err);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800761 return err;
762}
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800763
David Brownell97144c62007-10-16 01:28:16 -0700764/**
765 * rtc_irq_set_freq - set 2^N Hz periodic IRQ frequency for IRQ
766 * @rtc: the rtc device
767 * @task: currently registered with rtc_irq_register()
Alexandre Belloniacecb3a2018-07-25 14:58:10 +0200768 * @freq: positive frequency
David Brownell97144c62007-10-16 01:28:16 -0700769 * Context: any
770 *
771 * Note that rtc_irq_set_state() is used to enable or disable the
772 * periodic IRQs.
773 */
Alexandre Belloni8719d3c2018-07-25 15:07:09 +0200774int rtc_irq_set_freq(struct rtc_device *rtc, int freq)
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800775{
Alessandro Zummo56f10c62006-06-25 05:48:20 -0700776 int err = 0;
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800777
Thomas Gleixner6e7a3332011-07-22 09:12:51 +0000778 if (freq <= 0 || freq > RTC_MAX_FREQ)
Marcelo Roberto Jimenez83a06bf2011-02-02 16:04:02 -0200779 return -EINVAL;
Alexandre Belloniacecb3a2018-07-25 14:58:10 +0200780
781 rtc->irq_freq = freq;
782 while (rtc->pie_enabled && rtc_update_hrtimer(rtc, 1) < 0)
783 cpu_relax();
Baolin Wang29a1f592017-12-14 13:31:43 +0800784
785 trace_rtc_irq_set_freq(freq, err);
Alessandro Zummo0c86edc2006-03-27 01:16:37 -0800786 return err;
787}
John Stultz6610e082010-09-23 15:07:34 -0700788
789/**
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100790 * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue
John Stultz6610e082010-09-23 15:07:34 -0700791 * @rtc rtc device
792 * @timer timer being added.
793 *
794 * Enqueues a timer onto the rtc devices timerqueue and sets
795 * the next alarm event appropriately.
796 *
John Stultzaa0be0f2011-01-20 15:26:12 -0800797 * Sets the enabled bit on the added timer.
798 *
John Stultz6610e082010-09-23 15:07:34 -0700799 * Must hold ops_lock for proper serialization of timerqueue
800 */
John Stultzaa0be0f2011-01-20 15:26:12 -0800801static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer)
John Stultz6610e082010-09-23 15:07:34 -0700802{
Colin Ian King2b2f5ff2016-05-16 17:22:54 +0100803 struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue);
804 struct rtc_time tm;
805 ktime_t now;
806
John Stultzaa0be0f2011-01-20 15:26:12 -0800807 timer->enabled = 1;
Colin Ian King2b2f5ff2016-05-16 17:22:54 +0100808 __rtc_read_time(rtc, &tm);
809 now = rtc_tm_to_ktime(tm);
810
811 /* Skip over expired timers */
812 while (next) {
Thomas Gleixner2456e852016-12-25 11:38:40 +0100813 if (next->expires >= now)
Colin Ian King2b2f5ff2016-05-16 17:22:54 +0100814 break;
815 next = timerqueue_iterate_next(next);
816 }
817
John Stultz6610e082010-09-23 15:07:34 -0700818 timerqueue_add(&rtc->timerqueue, &timer->node);
Baolin Wang29a1f592017-12-14 13:31:43 +0800819 trace_rtc_timer_enqueue(timer);
Alexandre Belloni74717b22017-09-28 13:53:27 +0200820 if (!next || ktime_before(timer->node.expires, next->expires)) {
John Stultz6610e082010-09-23 15:07:34 -0700821 struct rtc_wkalrm alarm;
822 int err;
823 alarm.time = rtc_ktime_to_tm(timer->node.expires);
824 alarm.enabled = 1;
825 err = __rtc_set_alarm(rtc, &alarm);
Zoran Markovic14d0e342013-06-26 16:09:13 -0700826 if (err == -ETIME) {
827 pm_stay_awake(rtc->dev.parent);
John Stultz6610e082010-09-23 15:07:34 -0700828 schedule_work(&rtc->irqwork);
Zoran Markovic14d0e342013-06-26 16:09:13 -0700829 } else if (err) {
John Stultzaa0be0f2011-01-20 15:26:12 -0800830 timerqueue_del(&rtc->timerqueue, &timer->node);
Baolin Wang29a1f592017-12-14 13:31:43 +0800831 trace_rtc_timer_dequeue(timer);
John Stultzaa0be0f2011-01-20 15:26:12 -0800832 timer->enabled = 0;
833 return err;
834 }
John Stultz6610e082010-09-23 15:07:34 -0700835 }
John Stultzaa0be0f2011-01-20 15:26:12 -0800836 return 0;
John Stultz6610e082010-09-23 15:07:34 -0700837}
838
Rabin Vincent41c7f742011-11-22 11:03:14 +0100839static void rtc_alarm_disable(struct rtc_device *rtc)
840{
841 if (!rtc->ops || !rtc->ops->alarm_irq_enable)
842 return;
843
844 rtc->ops->alarm_irq_enable(rtc->dev.parent, false);
Baolin Wang29a1f592017-12-14 13:31:43 +0800845 trace_rtc_alarm_irq_enable(0, 0);
Rabin Vincent41c7f742011-11-22 11:03:14 +0100846}
847
John Stultz6610e082010-09-23 15:07:34 -0700848/**
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100849 * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue
John Stultz6610e082010-09-23 15:07:34 -0700850 * @rtc rtc device
851 * @timer timer being removed.
852 *
853 * Removes a timer onto the rtc devices timerqueue and sets
854 * the next alarm event appropriately.
855 *
John Stultzaa0be0f2011-01-20 15:26:12 -0800856 * Clears the enabled bit on the removed timer.
857 *
John Stultz6610e082010-09-23 15:07:34 -0700858 * Must hold ops_lock for proper serialization of timerqueue
859 */
John Stultzaa0be0f2011-01-20 15:26:12 -0800860static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer)
John Stultz6610e082010-09-23 15:07:34 -0700861{
862 struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue);
863 timerqueue_del(&rtc->timerqueue, &timer->node);
Baolin Wang29a1f592017-12-14 13:31:43 +0800864 trace_rtc_timer_dequeue(timer);
John Stultzaa0be0f2011-01-20 15:26:12 -0800865 timer->enabled = 0;
John Stultz6610e082010-09-23 15:07:34 -0700866 if (next == &timer->node) {
867 struct rtc_wkalrm alarm;
868 int err;
869 next = timerqueue_getnext(&rtc->timerqueue);
Rabin Vincent41c7f742011-11-22 11:03:14 +0100870 if (!next) {
871 rtc_alarm_disable(rtc);
John Stultz6610e082010-09-23 15:07:34 -0700872 return;
Rabin Vincent41c7f742011-11-22 11:03:14 +0100873 }
John Stultz6610e082010-09-23 15:07:34 -0700874 alarm.time = rtc_ktime_to_tm(next->expires);
875 alarm.enabled = 1;
876 err = __rtc_set_alarm(rtc, &alarm);
Zoran Markovic14d0e342013-06-26 16:09:13 -0700877 if (err == -ETIME) {
878 pm_stay_awake(rtc->dev.parent);
John Stultz6610e082010-09-23 15:07:34 -0700879 schedule_work(&rtc->irqwork);
Zoran Markovic14d0e342013-06-26 16:09:13 -0700880 }
John Stultz6610e082010-09-23 15:07:34 -0700881 }
882}
883
884/**
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100885 * rtc_timer_do_work - Expires rtc timers
John Stultz6610e082010-09-23 15:07:34 -0700886 * @rtc rtc device
887 * @timer timer being removed.
888 *
889 * Expires rtc timers. Reprograms next alarm event if needed.
890 * Called via worktask.
891 *
892 * Serializes access to timerqueue via ops_lock mutex
893 */
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100894void rtc_timer_do_work(struct work_struct *work)
John Stultz6610e082010-09-23 15:07:34 -0700895{
896 struct rtc_timer *timer;
897 struct timerqueue_node *next;
898 ktime_t now;
899 struct rtc_time tm;
900
901 struct rtc_device *rtc =
902 container_of(work, struct rtc_device, irqwork);
903
904 mutex_lock(&rtc->ops_lock);
905again:
906 __rtc_read_time(rtc, &tm);
907 now = rtc_tm_to_ktime(tm);
908 while ((next = timerqueue_getnext(&rtc->timerqueue))) {
Thomas Gleixner2456e852016-12-25 11:38:40 +0100909 if (next->expires > now)
John Stultz6610e082010-09-23 15:07:34 -0700910 break;
911
912 /* expire timer */
913 timer = container_of(next, struct rtc_timer, node);
914 timerqueue_del(&rtc->timerqueue, &timer->node);
Baolin Wang29a1f592017-12-14 13:31:43 +0800915 trace_rtc_timer_dequeue(timer);
John Stultz6610e082010-09-23 15:07:34 -0700916 timer->enabled = 0;
Alexandre Belloni5a5ba10f2018-07-26 15:40:56 +0200917 if (timer->func)
918 timer->func(timer->private_data);
John Stultz6610e082010-09-23 15:07:34 -0700919
Baolin Wang29a1f592017-12-14 13:31:43 +0800920 trace_rtc_timer_fired(timer);
John Stultz6610e082010-09-23 15:07:34 -0700921 /* Re-add/fwd periodic timers */
922 if (ktime_to_ns(timer->period)) {
923 timer->node.expires = ktime_add(timer->node.expires,
924 timer->period);
925 timer->enabled = 1;
926 timerqueue_add(&rtc->timerqueue, &timer->node);
Baolin Wang29a1f592017-12-14 13:31:43 +0800927 trace_rtc_timer_enqueue(timer);
John Stultz6610e082010-09-23 15:07:34 -0700928 }
929 }
930
931 /* Set next alarm */
932 if (next) {
933 struct rtc_wkalrm alarm;
934 int err;
Xunlei Pang6528b882014-12-10 15:54:26 -0800935 int retry = 3;
936
John Stultz6610e082010-09-23 15:07:34 -0700937 alarm.time = rtc_ktime_to_tm(next->expires);
938 alarm.enabled = 1;
Xunlei Pang6528b882014-12-10 15:54:26 -0800939reprogram:
John Stultz6610e082010-09-23 15:07:34 -0700940 err = __rtc_set_alarm(rtc, &alarm);
941 if (err == -ETIME)
942 goto again;
Xunlei Pang6528b882014-12-10 15:54:26 -0800943 else if (err) {
944 if (retry-- > 0)
945 goto reprogram;
946
947 timer = container_of(next, struct rtc_timer, node);
948 timerqueue_del(&rtc->timerqueue, &timer->node);
Baolin Wang29a1f592017-12-14 13:31:43 +0800949 trace_rtc_timer_dequeue(timer);
Xunlei Pang6528b882014-12-10 15:54:26 -0800950 timer->enabled = 0;
951 dev_err(&rtc->dev, "__rtc_set_alarm: err=%d\n", err);
952 goto again;
953 }
Rabin Vincent41c7f742011-11-22 11:03:14 +0100954 } else
955 rtc_alarm_disable(rtc);
John Stultz6610e082010-09-23 15:07:34 -0700956
Zoran Markovic14d0e342013-06-26 16:09:13 -0700957 pm_relax(rtc->dev.parent);
John Stultz6610e082010-09-23 15:07:34 -0700958 mutex_unlock(&rtc->ops_lock);
959}
960
961
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100962/* rtc_timer_init - Initializes an rtc_timer
John Stultz6610e082010-09-23 15:07:34 -0700963 * @timer: timer to be intiialized
964 * @f: function pointer to be called when timer fires
965 * @data: private data passed to function pointer
966 *
967 * Kernel interface to initializing an rtc_timer.
968 */
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700969void rtc_timer_init(struct rtc_timer *timer, void (*f)(void *p), void *data)
John Stultz6610e082010-09-23 15:07:34 -0700970{
971 timerqueue_init(&timer->node);
972 timer->enabled = 0;
Alexandre Belloni5a5ba10f2018-07-26 15:40:56 +0200973 timer->func = f;
974 timer->private_data = data;
John Stultz6610e082010-09-23 15:07:34 -0700975}
976
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100977/* rtc_timer_start - Sets an rtc_timer to fire in the future
John Stultz6610e082010-09-23 15:07:34 -0700978 * @ rtc: rtc device to be used
979 * @ timer: timer being set
980 * @ expires: time at which to expire the timer
981 * @ period: period that the timer will recur
982 *
983 * Kernel interface to set an rtc_timer
984 */
Sachin Kamat3ff2e132013-07-03 15:05:42 -0700985int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer *timer,
John Stultz6610e082010-09-23 15:07:34 -0700986 ktime_t expires, ktime_t period)
987{
988 int ret = 0;
989 mutex_lock(&rtc->ops_lock);
990 if (timer->enabled)
Thomas Gleixner96c8f062010-12-13 22:45:48 +0100991 rtc_timer_remove(rtc, timer);
John Stultz6610e082010-09-23 15:07:34 -0700992
993 timer->node.expires = expires;
994 timer->period = period;
995
John Stultzaa0be0f2011-01-20 15:26:12 -0800996 ret = rtc_timer_enqueue(rtc, timer);
John Stultz6610e082010-09-23 15:07:34 -0700997
998 mutex_unlock(&rtc->ops_lock);
999 return ret;
1000}
1001
Thomas Gleixner96c8f062010-12-13 22:45:48 +01001002/* rtc_timer_cancel - Stops an rtc_timer
John Stultz6610e082010-09-23 15:07:34 -07001003 * @ rtc: rtc device to be used
1004 * @ timer: timer being set
1005 *
1006 * Kernel interface to cancel an rtc_timer
1007 */
Krzysztof Kozlowski73744a62015-05-03 18:57:11 +09001008void rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer *timer)
John Stultz6610e082010-09-23 15:07:34 -07001009{
John Stultz6610e082010-09-23 15:07:34 -07001010 mutex_lock(&rtc->ops_lock);
1011 if (timer->enabled)
Thomas Gleixner96c8f062010-12-13 22:45:48 +01001012 rtc_timer_remove(rtc, timer);
John Stultz6610e082010-09-23 15:07:34 -07001013 mutex_unlock(&rtc->ops_lock);
John Stultz6610e082010-09-23 15:07:34 -07001014}
1015
Joshua Claytonb3967062016-02-05 12:41:11 -08001016/**
1017 * rtc_read_offset - Read the amount of rtc offset in parts per billion
1018 * @ rtc: rtc device to be used
1019 * @ offset: the offset in parts per billion
1020 *
1021 * see below for details.
1022 *
1023 * Kernel interface to read rtc clock offset
1024 * Returns 0 on success, or a negative number on error.
1025 * If read_offset() is not implemented for the rtc, return -EINVAL
1026 */
1027int rtc_read_offset(struct rtc_device *rtc, long *offset)
1028{
1029 int ret;
John Stultz6610e082010-09-23 15:07:34 -07001030
Joshua Claytonb3967062016-02-05 12:41:11 -08001031 if (!rtc->ops)
1032 return -ENODEV;
1033
1034 if (!rtc->ops->read_offset)
1035 return -EINVAL;
1036
1037 mutex_lock(&rtc->ops_lock);
1038 ret = rtc->ops->read_offset(rtc->dev.parent, offset);
1039 mutex_unlock(&rtc->ops_lock);
Baolin Wang29a1f592017-12-14 13:31:43 +08001040
1041 trace_rtc_read_offset(*offset, ret);
Joshua Claytonb3967062016-02-05 12:41:11 -08001042 return ret;
1043}
1044
1045/**
1046 * rtc_set_offset - Adjusts the duration of the average second
1047 * @ rtc: rtc device to be used
1048 * @ offset: the offset in parts per billion
1049 *
1050 * Some rtc's allow an adjustment to the average duration of a second
1051 * to compensate for differences in the actual clock rate due to temperature,
1052 * the crystal, capacitor, etc.
1053 *
Russell King8a25c8f2017-09-29 11:23:25 +01001054 * The adjustment applied is as follows:
1055 * t = t0 * (1 + offset * 1e-9)
1056 * where t0 is the measured length of 1 RTC second with offset = 0
1057 *
Joshua Claytonb3967062016-02-05 12:41:11 -08001058 * Kernel interface to adjust an rtc clock offset.
1059 * Return 0 on success, or a negative number on error.
1060 * If the rtc offset is not setable (or not implemented), return -EINVAL
1061 */
1062int rtc_set_offset(struct rtc_device *rtc, long offset)
1063{
1064 int ret;
1065
1066 if (!rtc->ops)
1067 return -ENODEV;
1068
1069 if (!rtc->ops->set_offset)
1070 return -EINVAL;
1071
1072 mutex_lock(&rtc->ops_lock);
1073 ret = rtc->ops->set_offset(rtc->dev.parent, offset);
1074 mutex_unlock(&rtc->ops_lock);
Baolin Wang29a1f592017-12-14 13:31:43 +08001075
1076 trace_rtc_set_offset(offset, ret);
Joshua Claytonb3967062016-02-05 12:41:11 -08001077 return ret;
1078}