Commit | Line | Data |
---|---|---|
0c86edc0 AZ |
1 | /* |
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> | |
d43c36dc | 15 | #include <linux/sched.h> |
2113852b | 16 | #include <linux/module.h> |
97144c67 | 17 | #include <linux/log2.h> |
6610e089 | 18 | #include <linux/workqueue.h> |
0c86edc0 | 19 | |
aa0be0f4 JS |
20 | static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer); |
21 | static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer); | |
22 | ||
6610e089 | 23 | static int __rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm) |
0c86edc0 AZ |
24 | { |
25 | int err; | |
0c86edc0 AZ |
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)); | |
cd966209 | 32 | err = rtc->ops->read_time(rtc->dev.parent, tm); |
0c86edc0 | 33 | } |
6610e089 JS |
34 | return err; |
35 | } | |
36 | ||
37 | int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm) | |
38 | { | |
39 | int err; | |
0c86edc0 | 40 | |
6610e089 JS |
41 | err = mutex_lock_interruptible(&rtc->ops_lock); |
42 | if (err) | |
43 | return err; | |
44 | ||
45 | err = __rtc_read_time(rtc, tm); | |
0c86edc0 AZ |
46 | mutex_unlock(&rtc->ops_lock); |
47 | return err; | |
48 | } | |
49 | EXPORT_SYMBOL_GPL(rtc_read_time); | |
50 | ||
ab6a2d70 | 51 | int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm) |
0c86edc0 AZ |
52 | { |
53 | int err; | |
0c86edc0 AZ |
54 | |
55 | err = rtc_valid_tm(tm); | |
56 | if (err != 0) | |
57 | return err; | |
58 | ||
59 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
60 | if (err) | |
b68bb263 | 61 | return err; |
0c86edc0 AZ |
62 | |
63 | if (!rtc->ops) | |
64 | err = -ENODEV; | |
bbccf83f | 65 | else if (rtc->ops->set_time) |
cd966209 | 66 | err = rtc->ops->set_time(rtc->dev.parent, tm); |
bbccf83f AZ |
67 | else if (rtc->ops->set_mmss) { |
68 | unsigned long secs; | |
69 | err = rtc_tm_to_time(tm, &secs); | |
70 | if (err == 0) | |
71 | err = rtc->ops->set_mmss(rtc->dev.parent, secs); | |
72 | } else | |
73 | err = -EINVAL; | |
0c86edc0 | 74 | |
14d0e347 | 75 | pm_stay_awake(rtc->dev.parent); |
0c86edc0 | 76 | mutex_unlock(&rtc->ops_lock); |
5f9679d2 N |
77 | /* A timer might have just expired */ |
78 | schedule_work(&rtc->irqwork); | |
0c86edc0 AZ |
79 | return err; |
80 | } | |
81 | EXPORT_SYMBOL_GPL(rtc_set_time); | |
82 | ||
ab6a2d70 | 83 | int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs) |
0c86edc0 AZ |
84 | { |
85 | int err; | |
0c86edc0 AZ |
86 | |
87 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
88 | if (err) | |
b68bb263 | 89 | return err; |
0c86edc0 AZ |
90 | |
91 | if (!rtc->ops) | |
92 | err = -ENODEV; | |
93 | else if (rtc->ops->set_mmss) | |
cd966209 | 94 | err = rtc->ops->set_mmss(rtc->dev.parent, secs); |
0c86edc0 AZ |
95 | else if (rtc->ops->read_time && rtc->ops->set_time) { |
96 | struct rtc_time new, old; | |
97 | ||
cd966209 | 98 | err = rtc->ops->read_time(rtc->dev.parent, &old); |
0c86edc0 AZ |
99 | if (err == 0) { |
100 | rtc_time_to_tm(secs, &new); | |
101 | ||
102 | /* | |
103 | * avoid writing when we're going to change the day of | |
104 | * the month. We will retry in the next minute. This | |
105 | * basically means that if the RTC must not drift | |
106 | * by more than 1 minute in 11 minutes. | |
107 | */ | |
108 | if (!((old.tm_hour == 23 && old.tm_min == 59) || | |
109 | (new.tm_hour == 23 && new.tm_min == 59))) | |
cd966209 | 110 | err = rtc->ops->set_time(rtc->dev.parent, |
ab6a2d70 | 111 | &new); |
0c86edc0 | 112 | } |
3ff2e13c | 113 | } else { |
0c86edc0 | 114 | err = -EINVAL; |
3ff2e13c | 115 | } |
0c86edc0 | 116 | |
14d0e347 | 117 | pm_stay_awake(rtc->dev.parent); |
0c86edc0 | 118 | mutex_unlock(&rtc->ops_lock); |
5f9679d2 N |
119 | /* A timer might have just expired */ |
120 | schedule_work(&rtc->irqwork); | |
0c86edc0 AZ |
121 | |
122 | return err; | |
123 | } | |
124 | EXPORT_SYMBOL_GPL(rtc_set_mmss); | |
125 | ||
f44f7f96 JS |
126 | static int rtc_read_alarm_internal(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
127 | { | |
128 | int err; | |
129 | ||
130 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
131 | if (err) | |
132 | return err; | |
133 | ||
134 | if (rtc->ops == NULL) | |
135 | err = -ENODEV; | |
136 | else if (!rtc->ops->read_alarm) | |
137 | err = -EINVAL; | |
138 | else { | |
139 | memset(alarm, 0, sizeof(struct rtc_wkalrm)); | |
140 | err = rtc->ops->read_alarm(rtc->dev.parent, alarm); | |
141 | } | |
142 | ||
143 | mutex_unlock(&rtc->ops_lock); | |
144 | return err; | |
145 | } | |
146 | ||
147 | int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) | |
148 | { | |
149 | int err; | |
150 | struct rtc_time before, now; | |
151 | int first_time = 1; | |
152 | unsigned long t_now, t_alm; | |
153 | enum { none, day, month, year } missing = none; | |
154 | unsigned days; | |
155 | ||
156 | /* The lower level RTC driver may return -1 in some fields, | |
157 | * creating invalid alarm->time values, for reasons like: | |
158 | * | |
159 | * - The hardware may not be capable of filling them in; | |
160 | * many alarms match only on time-of-day fields, not | |
161 | * day/month/year calendar data. | |
162 | * | |
163 | * - Some hardware uses illegal values as "wildcard" match | |
164 | * values, which non-Linux firmware (like a BIOS) may try | |
165 | * to set up as e.g. "alarm 15 minutes after each hour". | |
166 | * Linux uses only oneshot alarms. | |
167 | * | |
168 | * When we see that here, we deal with it by using values from | |
169 | * a current RTC timestamp for any missing (-1) values. The | |
170 | * RTC driver prevents "periodic alarm" modes. | |
171 | * | |
172 | * But this can be racey, because some fields of the RTC timestamp | |
173 | * may have wrapped in the interval since we read the RTC alarm, | |
174 | * which would lead to us inserting inconsistent values in place | |
175 | * of the -1 fields. | |
176 | * | |
177 | * Reading the alarm and timestamp in the reverse sequence | |
178 | * would have the same race condition, and not solve the issue. | |
179 | * | |
180 | * So, we must first read the RTC timestamp, | |
181 | * then read the RTC alarm value, | |
182 | * and then read a second RTC timestamp. | |
183 | * | |
184 | * If any fields of the second timestamp have changed | |
185 | * when compared with the first timestamp, then we know | |
186 | * our timestamp may be inconsistent with that used by | |
187 | * the low-level rtc_read_alarm_internal() function. | |
188 | * | |
189 | * So, when the two timestamps disagree, we just loop and do | |
190 | * the process again to get a fully consistent set of values. | |
191 | * | |
192 | * This could all instead be done in the lower level driver, | |
193 | * but since more than one lower level RTC implementation needs it, | |
194 | * then it's probably best best to do it here instead of there.. | |
195 | */ | |
196 | ||
197 | /* Get the "before" timestamp */ | |
198 | err = rtc_read_time(rtc, &before); | |
199 | if (err < 0) | |
200 | return err; | |
201 | do { | |
202 | if (!first_time) | |
203 | memcpy(&before, &now, sizeof(struct rtc_time)); | |
204 | first_time = 0; | |
205 | ||
206 | /* get the RTC alarm values, which may be incomplete */ | |
207 | err = rtc_read_alarm_internal(rtc, alarm); | |
208 | if (err) | |
209 | return err; | |
210 | ||
211 | /* full-function RTCs won't have such missing fields */ | |
212 | if (rtc_valid_tm(&alarm->time) == 0) | |
213 | return 0; | |
214 | ||
215 | /* get the "after" timestamp, to detect wrapped fields */ | |
216 | err = rtc_read_time(rtc, &now); | |
217 | if (err < 0) | |
218 | return err; | |
219 | ||
220 | /* note that tm_sec is a "don't care" value here: */ | |
221 | } while ( before.tm_min != now.tm_min | |
222 | || before.tm_hour != now.tm_hour | |
223 | || before.tm_mon != now.tm_mon | |
224 | || before.tm_year != now.tm_year); | |
225 | ||
226 | /* Fill in the missing alarm fields using the timestamp; we | |
227 | * know there's at least one since alarm->time is invalid. | |
228 | */ | |
229 | if (alarm->time.tm_sec == -1) | |
230 | alarm->time.tm_sec = now.tm_sec; | |
231 | if (alarm->time.tm_min == -1) | |
232 | alarm->time.tm_min = now.tm_min; | |
233 | if (alarm->time.tm_hour == -1) | |
234 | alarm->time.tm_hour = now.tm_hour; | |
235 | ||
236 | /* For simplicity, only support date rollover for now */ | |
e74a8f2e | 237 | if (alarm->time.tm_mday < 1 || alarm->time.tm_mday > 31) { |
f44f7f96 JS |
238 | alarm->time.tm_mday = now.tm_mday; |
239 | missing = day; | |
240 | } | |
e74a8f2e | 241 | if ((unsigned)alarm->time.tm_mon >= 12) { |
f44f7f96 JS |
242 | alarm->time.tm_mon = now.tm_mon; |
243 | if (missing == none) | |
244 | missing = month; | |
245 | } | |
246 | if (alarm->time.tm_year == -1) { | |
247 | alarm->time.tm_year = now.tm_year; | |
248 | if (missing == none) | |
249 | missing = year; | |
250 | } | |
251 | ||
252 | /* with luck, no rollover is needed */ | |
253 | rtc_tm_to_time(&now, &t_now); | |
254 | rtc_tm_to_time(&alarm->time, &t_alm); | |
255 | if (t_now < t_alm) | |
256 | goto done; | |
257 | ||
258 | switch (missing) { | |
259 | ||
260 | /* 24 hour rollover ... if it's now 10am Monday, an alarm that | |
261 | * that will trigger at 5am will do so at 5am Tuesday, which | |
262 | * could also be in the next month or year. This is a common | |
263 | * case, especially for PCs. | |
264 | */ | |
265 | case day: | |
266 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "day"); | |
267 | t_alm += 24 * 60 * 60; | |
268 | rtc_time_to_tm(t_alm, &alarm->time); | |
269 | break; | |
270 | ||
271 | /* Month rollover ... if it's the 31th, an alarm on the 3rd will | |
272 | * be next month. An alarm matching on the 30th, 29th, or 28th | |
273 | * may end up in the month after that! Many newer PCs support | |
274 | * this type of alarm. | |
275 | */ | |
276 | case month: | |
277 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "month"); | |
278 | do { | |
279 | if (alarm->time.tm_mon < 11) | |
280 | alarm->time.tm_mon++; | |
281 | else { | |
282 | alarm->time.tm_mon = 0; | |
283 | alarm->time.tm_year++; | |
284 | } | |
285 | days = rtc_month_days(alarm->time.tm_mon, | |
286 | alarm->time.tm_year); | |
287 | } while (days < alarm->time.tm_mday); | |
288 | break; | |
289 | ||
290 | /* Year rollover ... easy except for leap years! */ | |
291 | case year: | |
292 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "year"); | |
293 | do { | |
294 | alarm->time.tm_year++; | |
ee1d9014 AN |
295 | } while (!is_leap_year(alarm->time.tm_year + 1900) |
296 | && rtc_valid_tm(&alarm->time) != 0); | |
f44f7f96 JS |
297 | break; |
298 | ||
299 | default: | |
300 | dev_warn(&rtc->dev, "alarm rollover not handled\n"); | |
301 | } | |
302 | ||
303 | done: | |
ee1d9014 AN |
304 | err = rtc_valid_tm(&alarm->time); |
305 | ||
306 | if (err) { | |
307 | dev_warn(&rtc->dev, "invalid alarm value: %d-%d-%d %d:%d:%d\n", | |
308 | alarm->time.tm_year + 1900, alarm->time.tm_mon + 1, | |
309 | alarm->time.tm_mday, alarm->time.tm_hour, alarm->time.tm_min, | |
310 | alarm->time.tm_sec); | |
311 | } | |
312 | ||
313 | return err; | |
f44f7f96 JS |
314 | } |
315 | ||
6610e089 | 316 | int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0c86edc0 AZ |
317 | { |
318 | int err; | |
0c86edc0 AZ |
319 | |
320 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
321 | if (err) | |
b68bb263 | 322 | return err; |
d5553a55 JS |
323 | if (rtc->ops == NULL) |
324 | err = -ENODEV; | |
325 | else if (!rtc->ops->read_alarm) | |
326 | err = -EINVAL; | |
327 | else { | |
328 | memset(alarm, 0, sizeof(struct rtc_wkalrm)); | |
329 | alarm->enabled = rtc->aie_timer.enabled; | |
6610e089 | 330 | alarm->time = rtc_ktime_to_tm(rtc->aie_timer.node.expires); |
d5553a55 | 331 | } |
0c86edc0 | 332 | mutex_unlock(&rtc->ops_lock); |
6610e089 | 333 | |
d5553a55 | 334 | return err; |
0c86edc0 | 335 | } |
6610e089 | 336 | EXPORT_SYMBOL_GPL(rtc_read_alarm); |
0e36a9a4 | 337 | |
d576fe49 | 338 | static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0e36a9a4 | 339 | { |
6610e089 JS |
340 | struct rtc_time tm; |
341 | long now, scheduled; | |
0e36a9a4 | 342 | int err; |
0e36a9a4 | 343 | |
6610e089 JS |
344 | err = rtc_valid_tm(&alarm->time); |
345 | if (err) | |
0e36a9a4 | 346 | return err; |
6610e089 | 347 | rtc_tm_to_time(&alarm->time, &scheduled); |
a01cc657 | 348 | |
6610e089 JS |
349 | /* Make sure we're not setting alarms in the past */ |
350 | err = __rtc_read_time(rtc, &tm); | |
351 | rtc_tm_to_time(&tm, &now); | |
352 | if (scheduled <= now) | |
353 | return -ETIME; | |
354 | /* | |
355 | * XXX - We just checked to make sure the alarm time is not | |
356 | * in the past, but there is still a race window where if | |
357 | * the is alarm set for the next second and the second ticks | |
358 | * over right here, before we set the alarm. | |
a01cc657 | 359 | */ |
a01cc657 | 360 | |
157e8bf8 LT |
361 | if (!rtc->ops) |
362 | err = -ENODEV; | |
363 | else if (!rtc->ops->set_alarm) | |
364 | err = -EINVAL; | |
365 | else | |
366 | err = rtc->ops->set_alarm(rtc->dev.parent, alarm); | |
367 | ||
368 | return err; | |
0e36a9a4 | 369 | } |
0c86edc0 | 370 | |
ab6a2d70 | 371 | int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0c86edc0 AZ |
372 | { |
373 | int err; | |
0c86edc0 | 374 | |
f8245c26 DB |
375 | err = rtc_valid_tm(&alarm->time); |
376 | if (err != 0) | |
377 | return err; | |
378 | ||
0c86edc0 AZ |
379 | err = mutex_lock_interruptible(&rtc->ops_lock); |
380 | if (err) | |
b68bb263 | 381 | return err; |
3ff2e13c | 382 | if (rtc->aie_timer.enabled) |
96c8f06a | 383 | rtc_timer_remove(rtc, &rtc->aie_timer); |
3ff2e13c | 384 | |
6610e089 JS |
385 | rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time); |
386 | rtc->aie_timer.period = ktime_set(0, 0); | |
3ff2e13c | 387 | if (alarm->enabled) |
aa0be0f4 | 388 | err = rtc_timer_enqueue(rtc, &rtc->aie_timer); |
3ff2e13c | 389 | |
0c86edc0 | 390 | mutex_unlock(&rtc->ops_lock); |
aa0be0f4 | 391 | return err; |
0c86edc0 AZ |
392 | } |
393 | EXPORT_SYMBOL_GPL(rtc_set_alarm); | |
394 | ||
f6d5b331 JS |
395 | /* Called once per device from rtc_device_register */ |
396 | int rtc_initialize_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) | |
397 | { | |
398 | int err; | |
bd729d72 | 399 | struct rtc_time now; |
f6d5b331 JS |
400 | |
401 | err = rtc_valid_tm(&alarm->time); | |
402 | if (err != 0) | |
403 | return err; | |
404 | ||
bd729d72 JS |
405 | err = rtc_read_time(rtc, &now); |
406 | if (err) | |
407 | return err; | |
408 | ||
f6d5b331 JS |
409 | err = mutex_lock_interruptible(&rtc->ops_lock); |
410 | if (err) | |
411 | return err; | |
412 | ||
413 | rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time); | |
414 | rtc->aie_timer.period = ktime_set(0, 0); | |
bd729d72 JS |
415 | |
416 | /* Alarm has to be enabled & in the futrure for us to enqueue it */ | |
417 | if (alarm->enabled && (rtc_tm_to_ktime(now).tv64 < | |
418 | rtc->aie_timer.node.expires.tv64)) { | |
419 | ||
f6d5b331 JS |
420 | rtc->aie_timer.enabled = 1; |
421 | timerqueue_add(&rtc->timerqueue, &rtc->aie_timer.node); | |
422 | } | |
423 | mutex_unlock(&rtc->ops_lock); | |
424 | return err; | |
425 | } | |
426 | EXPORT_SYMBOL_GPL(rtc_initialize_alarm); | |
427 | ||
428 | ||
429 | ||
099e6576 AZ |
430 | int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled) |
431 | { | |
432 | int err = mutex_lock_interruptible(&rtc->ops_lock); | |
433 | if (err) | |
434 | return err; | |
435 | ||
6610e089 | 436 | if (rtc->aie_timer.enabled != enabled) { |
aa0be0f4 JS |
437 | if (enabled) |
438 | err = rtc_timer_enqueue(rtc, &rtc->aie_timer); | |
439 | else | |
96c8f06a | 440 | rtc_timer_remove(rtc, &rtc->aie_timer); |
6610e089 JS |
441 | } |
442 | ||
aa0be0f4 | 443 | if (err) |
516373b8 UKK |
444 | /* nothing */; |
445 | else if (!rtc->ops) | |
099e6576 AZ |
446 | err = -ENODEV; |
447 | else if (!rtc->ops->alarm_irq_enable) | |
448 | err = -EINVAL; | |
449 | else | |
450 | err = rtc->ops->alarm_irq_enable(rtc->dev.parent, enabled); | |
451 | ||
452 | mutex_unlock(&rtc->ops_lock); | |
453 | return err; | |
454 | } | |
455 | EXPORT_SYMBOL_GPL(rtc_alarm_irq_enable); | |
456 | ||
457 | int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled) | |
458 | { | |
459 | int err = mutex_lock_interruptible(&rtc->ops_lock); | |
460 | if (err) | |
461 | return err; | |
462 | ||
456d66ec JS |
463 | #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL |
464 | if (enabled == 0 && rtc->uie_irq_active) { | |
465 | mutex_unlock(&rtc->ops_lock); | |
466 | return rtc_dev_update_irq_enable_emul(rtc, 0); | |
467 | } | |
468 | #endif | |
6610e089 JS |
469 | /* make sure we're changing state */ |
470 | if (rtc->uie_rtctimer.enabled == enabled) | |
471 | goto out; | |
472 | ||
4a649903 JS |
473 | if (rtc->uie_unsupported) { |
474 | err = -EINVAL; | |
475 | goto out; | |
476 | } | |
477 | ||
6610e089 JS |
478 | if (enabled) { |
479 | struct rtc_time tm; | |
480 | ktime_t now, onesec; | |
481 | ||
482 | __rtc_read_time(rtc, &tm); | |
483 | onesec = ktime_set(1, 0); | |
484 | now = rtc_tm_to_ktime(tm); | |
485 | rtc->uie_rtctimer.node.expires = ktime_add(now, onesec); | |
486 | rtc->uie_rtctimer.period = ktime_set(1, 0); | |
aa0be0f4 JS |
487 | err = rtc_timer_enqueue(rtc, &rtc->uie_rtctimer); |
488 | } else | |
96c8f06a | 489 | rtc_timer_remove(rtc, &rtc->uie_rtctimer); |
099e6576 | 490 | |
6610e089 | 491 | out: |
099e6576 | 492 | mutex_unlock(&rtc->ops_lock); |
456d66ec JS |
493 | #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL |
494 | /* | |
495 | * Enable emulation if the driver did not provide | |
496 | * the update_irq_enable function pointer or if returned | |
497 | * -EINVAL to signal that it has been configured without | |
498 | * interrupts or that are not available at the moment. | |
499 | */ | |
500 | if (err == -EINVAL) | |
501 | err = rtc_dev_update_irq_enable_emul(rtc, enabled); | |
502 | #endif | |
099e6576 | 503 | return err; |
6610e089 | 504 | |
099e6576 AZ |
505 | } |
506 | EXPORT_SYMBOL_GPL(rtc_update_irq_enable); | |
507 | ||
6610e089 | 508 | |
d728b1e6 | 509 | /** |
6610e089 JS |
510 | * rtc_handle_legacy_irq - AIE, UIE and PIE event hook |
511 | * @rtc: pointer to the rtc device | |
512 | * | |
513 | * This function is called when an AIE, UIE or PIE mode interrupt | |
25985edc | 514 | * has occurred (or been emulated). |
6610e089 JS |
515 | * |
516 | * Triggers the registered irq_task function callback. | |
d728b1e6 | 517 | */ |
456d66ec | 518 | void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode) |
0c86edc0 | 519 | { |
e6229bec AN |
520 | unsigned long flags; |
521 | ||
6610e089 | 522 | /* mark one irq of the appropriate mode */ |
e6229bec | 523 | spin_lock_irqsave(&rtc->irq_lock, flags); |
6610e089 | 524 | rtc->irq_data = (rtc->irq_data + (num << 8)) | (RTC_IRQF|mode); |
e6229bec | 525 | spin_unlock_irqrestore(&rtc->irq_lock, flags); |
0c86edc0 | 526 | |
6610e089 | 527 | /* call the task func */ |
e6229bec | 528 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
529 | if (rtc->irq_task) |
530 | rtc->irq_task->func(rtc->irq_task->private_data); | |
e6229bec | 531 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
532 | |
533 | wake_up_interruptible(&rtc->irq_queue); | |
534 | kill_fasync(&rtc->async_queue, SIGIO, POLL_IN); | |
535 | } | |
6610e089 JS |
536 | |
537 | ||
538 | /** | |
539 | * rtc_aie_update_irq - AIE mode rtctimer hook | |
540 | * @private: pointer to the rtc_device | |
541 | * | |
542 | * This functions is called when the aie_timer expires. | |
543 | */ | |
544 | void rtc_aie_update_irq(void *private) | |
545 | { | |
546 | struct rtc_device *rtc = (struct rtc_device *)private; | |
547 | rtc_handle_legacy_irq(rtc, 1, RTC_AF); | |
548 | } | |
549 | ||
550 | ||
551 | /** | |
552 | * rtc_uie_update_irq - UIE mode rtctimer hook | |
553 | * @private: pointer to the rtc_device | |
554 | * | |
555 | * This functions is called when the uie_timer expires. | |
556 | */ | |
557 | void rtc_uie_update_irq(void *private) | |
558 | { | |
559 | struct rtc_device *rtc = (struct rtc_device *)private; | |
560 | rtc_handle_legacy_irq(rtc, 1, RTC_UF); | |
561 | } | |
562 | ||
563 | ||
564 | /** | |
565 | * rtc_pie_update_irq - PIE mode hrtimer hook | |
566 | * @timer: pointer to the pie mode hrtimer | |
567 | * | |
568 | * This function is used to emulate PIE mode interrupts | |
569 | * using an hrtimer. This function is called when the periodic | |
570 | * hrtimer expires. | |
571 | */ | |
572 | enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer) | |
573 | { | |
574 | struct rtc_device *rtc; | |
575 | ktime_t period; | |
576 | int count; | |
577 | rtc = container_of(timer, struct rtc_device, pie_timer); | |
578 | ||
579 | period = ktime_set(0, NSEC_PER_SEC/rtc->irq_freq); | |
580 | count = hrtimer_forward_now(timer, period); | |
581 | ||
582 | rtc_handle_legacy_irq(rtc, count, RTC_PF); | |
583 | ||
584 | return HRTIMER_RESTART; | |
585 | } | |
586 | ||
587 | /** | |
588 | * rtc_update_irq - Triggered when a RTC interrupt occurs. | |
589 | * @rtc: the rtc device | |
590 | * @num: how many irqs are being reported (usually one) | |
591 | * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF | |
592 | * Context: any | |
593 | */ | |
594 | void rtc_update_irq(struct rtc_device *rtc, | |
595 | unsigned long num, unsigned long events) | |
596 | { | |
131c9cc8 AZ |
597 | if (unlikely(IS_ERR_OR_NULL(rtc))) |
598 | return; | |
599 | ||
7523ceed | 600 | pm_stay_awake(rtc->dev.parent); |
6610e089 JS |
601 | schedule_work(&rtc->irqwork); |
602 | } | |
0c86edc0 AZ |
603 | EXPORT_SYMBOL_GPL(rtc_update_irq); |
604 | ||
9f3b795a | 605 | static int __rtc_match(struct device *dev, const void *data) |
71da8905 | 606 | { |
9f3b795a | 607 | const char *name = data; |
71da8905 | 608 | |
d4afc76c | 609 | if (strcmp(dev_name(dev), name) == 0) |
71da8905 DY |
610 | return 1; |
611 | return 0; | |
612 | } | |
613 | ||
9f3b795a | 614 | struct rtc_device *rtc_class_open(const char *name) |
0c86edc0 | 615 | { |
cd966209 | 616 | struct device *dev; |
ab6a2d70 | 617 | struct rtc_device *rtc = NULL; |
0c86edc0 | 618 | |
695794ae | 619 | dev = class_find_device(rtc_class, NULL, name, __rtc_match); |
71da8905 DY |
620 | if (dev) |
621 | rtc = to_rtc_device(dev); | |
0c86edc0 | 622 | |
ab6a2d70 DB |
623 | if (rtc) { |
624 | if (!try_module_get(rtc->owner)) { | |
cd966209 | 625 | put_device(dev); |
ab6a2d70 DB |
626 | rtc = NULL; |
627 | } | |
0c86edc0 | 628 | } |
0c86edc0 | 629 | |
ab6a2d70 | 630 | return rtc; |
0c86edc0 AZ |
631 | } |
632 | EXPORT_SYMBOL_GPL(rtc_class_open); | |
633 | ||
ab6a2d70 | 634 | void rtc_class_close(struct rtc_device *rtc) |
0c86edc0 | 635 | { |
ab6a2d70 | 636 | module_put(rtc->owner); |
cd966209 | 637 | put_device(&rtc->dev); |
0c86edc0 AZ |
638 | } |
639 | EXPORT_SYMBOL_GPL(rtc_class_close); | |
640 | ||
ab6a2d70 | 641 | int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task) |
0c86edc0 AZ |
642 | { |
643 | int retval = -EBUSY; | |
0c86edc0 AZ |
644 | |
645 | if (task == NULL || task->func == NULL) | |
646 | return -EINVAL; | |
647 | ||
d691eb90 | 648 | /* Cannot register while the char dev is in use */ |
372a302e | 649 | if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags)) |
d691eb90 AZ |
650 | return -EBUSY; |
651 | ||
d728b1e6 | 652 | spin_lock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
653 | if (rtc->irq_task == NULL) { |
654 | rtc->irq_task = task; | |
655 | retval = 0; | |
656 | } | |
d728b1e6 | 657 | spin_unlock_irq(&rtc->irq_task_lock); |
0c86edc0 | 658 | |
372a302e | 659 | clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags); |
d691eb90 | 660 | |
0c86edc0 AZ |
661 | return retval; |
662 | } | |
663 | EXPORT_SYMBOL_GPL(rtc_irq_register); | |
664 | ||
ab6a2d70 | 665 | void rtc_irq_unregister(struct rtc_device *rtc, struct rtc_task *task) |
0c86edc0 | 666 | { |
d728b1e6 | 667 | spin_lock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
668 | if (rtc->irq_task == task) |
669 | rtc->irq_task = NULL; | |
d728b1e6 | 670 | spin_unlock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
671 | } |
672 | EXPORT_SYMBOL_GPL(rtc_irq_unregister); | |
673 | ||
3c8bb90e TG |
674 | static int rtc_update_hrtimer(struct rtc_device *rtc, int enabled) |
675 | { | |
676 | /* | |
677 | * We always cancel the timer here first, because otherwise | |
678 | * we could run into BUG_ON(timer->state != HRTIMER_STATE_CALLBACK); | |
679 | * when we manage to start the timer before the callback | |
680 | * returns HRTIMER_RESTART. | |
681 | * | |
682 | * We cannot use hrtimer_cancel() here as a running callback | |
683 | * could be blocked on rtc->irq_task_lock and hrtimer_cancel() | |
684 | * would spin forever. | |
685 | */ | |
686 | if (hrtimer_try_to_cancel(&rtc->pie_timer) < 0) | |
687 | return -1; | |
688 | ||
689 | if (enabled) { | |
690 | ktime_t period = ktime_set(0, NSEC_PER_SEC / rtc->irq_freq); | |
691 | ||
692 | hrtimer_start(&rtc->pie_timer, period, HRTIMER_MODE_REL); | |
693 | } | |
694 | return 0; | |
695 | } | |
696 | ||
97144c67 DB |
697 | /** |
698 | * rtc_irq_set_state - enable/disable 2^N Hz periodic IRQs | |
699 | * @rtc: the rtc device | |
700 | * @task: currently registered with rtc_irq_register() | |
701 | * @enabled: true to enable periodic IRQs | |
702 | * Context: any | |
703 | * | |
704 | * Note that rtc_irq_set_freq() should previously have been used to | |
705 | * specify the desired frequency of periodic IRQ task->func() callbacks. | |
706 | */ | |
ab6a2d70 | 707 | int rtc_irq_set_state(struct rtc_device *rtc, struct rtc_task *task, int enabled) |
0c86edc0 AZ |
708 | { |
709 | int err = 0; | |
710 | unsigned long flags; | |
0c86edc0 | 711 | |
3c8bb90e | 712 | retry: |
0c86edc0 | 713 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
d691eb90 AZ |
714 | if (rtc->irq_task != NULL && task == NULL) |
715 | err = -EBUSY; | |
0734e27f | 716 | else if (rtc->irq_task != task) |
d691eb90 | 717 | err = -EACCES; |
0734e27f | 718 | else { |
3c8bb90e TG |
719 | if (rtc_update_hrtimer(rtc, enabled) < 0) { |
720 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); | |
721 | cpu_relax(); | |
722 | goto retry; | |
723 | } | |
724 | rtc->pie_enabled = enabled; | |
6610e089 | 725 | } |
6610e089 | 726 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
727 | return err; |
728 | } | |
729 | EXPORT_SYMBOL_GPL(rtc_irq_set_state); | |
730 | ||
97144c67 DB |
731 | /** |
732 | * rtc_irq_set_freq - set 2^N Hz periodic IRQ frequency for IRQ | |
733 | * @rtc: the rtc device | |
734 | * @task: currently registered with rtc_irq_register() | |
735 | * @freq: positive frequency with which task->func() will be called | |
736 | * Context: any | |
737 | * | |
738 | * Note that rtc_irq_set_state() is used to enable or disable the | |
739 | * periodic IRQs. | |
740 | */ | |
ab6a2d70 | 741 | int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq) |
0c86edc0 | 742 | { |
56f10c63 | 743 | int err = 0; |
0c86edc0 | 744 | unsigned long flags; |
0c86edc0 | 745 | |
6e7a333e | 746 | if (freq <= 0 || freq > RTC_MAX_FREQ) |
83a06bf5 | 747 | return -EINVAL; |
3c8bb90e | 748 | retry: |
0c86edc0 | 749 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
d691eb90 AZ |
750 | if (rtc->irq_task != NULL && task == NULL) |
751 | err = -EBUSY; | |
0734e27f | 752 | else if (rtc->irq_task != task) |
d691eb90 | 753 | err = -EACCES; |
0734e27f | 754 | else { |
6610e089 | 755 | rtc->irq_freq = freq; |
3c8bb90e TG |
756 | if (rtc->pie_enabled && rtc_update_hrtimer(rtc, 1) < 0) { |
757 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); | |
758 | cpu_relax(); | |
759 | goto retry; | |
6610e089 | 760 | } |
0c86edc0 | 761 | } |
6610e089 | 762 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
763 | return err; |
764 | } | |
2601a464 | 765 | EXPORT_SYMBOL_GPL(rtc_irq_set_freq); |
6610e089 JS |
766 | |
767 | /** | |
96c8f06a | 768 | * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue |
6610e089 JS |
769 | * @rtc rtc device |
770 | * @timer timer being added. | |
771 | * | |
772 | * Enqueues a timer onto the rtc devices timerqueue and sets | |
773 | * the next alarm event appropriately. | |
774 | * | |
aa0be0f4 JS |
775 | * Sets the enabled bit on the added timer. |
776 | * | |
6610e089 JS |
777 | * Must hold ops_lock for proper serialization of timerqueue |
778 | */ | |
aa0be0f4 | 779 | static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) |
6610e089 | 780 | { |
aa0be0f4 | 781 | timer->enabled = 1; |
6610e089 JS |
782 | timerqueue_add(&rtc->timerqueue, &timer->node); |
783 | if (&timer->node == timerqueue_getnext(&rtc->timerqueue)) { | |
784 | struct rtc_wkalrm alarm; | |
785 | int err; | |
786 | alarm.time = rtc_ktime_to_tm(timer->node.expires); | |
787 | alarm.enabled = 1; | |
788 | err = __rtc_set_alarm(rtc, &alarm); | |
14d0e347 ZM |
789 | if (err == -ETIME) { |
790 | pm_stay_awake(rtc->dev.parent); | |
6610e089 | 791 | schedule_work(&rtc->irqwork); |
14d0e347 | 792 | } else if (err) { |
aa0be0f4 JS |
793 | timerqueue_del(&rtc->timerqueue, &timer->node); |
794 | timer->enabled = 0; | |
795 | return err; | |
796 | } | |
6610e089 | 797 | } |
aa0be0f4 | 798 | return 0; |
6610e089 JS |
799 | } |
800 | ||
41c7f742 RV |
801 | static void rtc_alarm_disable(struct rtc_device *rtc) |
802 | { | |
803 | if (!rtc->ops || !rtc->ops->alarm_irq_enable) | |
804 | return; | |
805 | ||
806 | rtc->ops->alarm_irq_enable(rtc->dev.parent, false); | |
807 | } | |
808 | ||
6610e089 | 809 | /** |
96c8f06a | 810 | * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue |
6610e089 JS |
811 | * @rtc rtc device |
812 | * @timer timer being removed. | |
813 | * | |
814 | * Removes a timer onto the rtc devices timerqueue and sets | |
815 | * the next alarm event appropriately. | |
816 | * | |
aa0be0f4 JS |
817 | * Clears the enabled bit on the removed timer. |
818 | * | |
6610e089 JS |
819 | * Must hold ops_lock for proper serialization of timerqueue |
820 | */ | |
aa0be0f4 | 821 | static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer) |
6610e089 JS |
822 | { |
823 | struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue); | |
824 | timerqueue_del(&rtc->timerqueue, &timer->node); | |
aa0be0f4 | 825 | timer->enabled = 0; |
6610e089 JS |
826 | if (next == &timer->node) { |
827 | struct rtc_wkalrm alarm; | |
828 | int err; | |
829 | next = timerqueue_getnext(&rtc->timerqueue); | |
41c7f742 RV |
830 | if (!next) { |
831 | rtc_alarm_disable(rtc); | |
6610e089 | 832 | return; |
41c7f742 | 833 | } |
6610e089 JS |
834 | alarm.time = rtc_ktime_to_tm(next->expires); |
835 | alarm.enabled = 1; | |
836 | err = __rtc_set_alarm(rtc, &alarm); | |
14d0e347 ZM |
837 | if (err == -ETIME) { |
838 | pm_stay_awake(rtc->dev.parent); | |
6610e089 | 839 | schedule_work(&rtc->irqwork); |
14d0e347 | 840 | } |
6610e089 JS |
841 | } |
842 | } | |
843 | ||
844 | /** | |
96c8f06a | 845 | * rtc_timer_do_work - Expires rtc timers |
6610e089 JS |
846 | * @rtc rtc device |
847 | * @timer timer being removed. | |
848 | * | |
849 | * Expires rtc timers. Reprograms next alarm event if needed. | |
850 | * Called via worktask. | |
851 | * | |
852 | * Serializes access to timerqueue via ops_lock mutex | |
853 | */ | |
96c8f06a | 854 | void rtc_timer_do_work(struct work_struct *work) |
6610e089 JS |
855 | { |
856 | struct rtc_timer *timer; | |
857 | struct timerqueue_node *next; | |
858 | ktime_t now; | |
859 | struct rtc_time tm; | |
860 | ||
861 | struct rtc_device *rtc = | |
862 | container_of(work, struct rtc_device, irqwork); | |
863 | ||
864 | mutex_lock(&rtc->ops_lock); | |
865 | again: | |
866 | __rtc_read_time(rtc, &tm); | |
867 | now = rtc_tm_to_ktime(tm); | |
868 | while ((next = timerqueue_getnext(&rtc->timerqueue))) { | |
869 | if (next->expires.tv64 > now.tv64) | |
870 | break; | |
871 | ||
872 | /* expire timer */ | |
873 | timer = container_of(next, struct rtc_timer, node); | |
874 | timerqueue_del(&rtc->timerqueue, &timer->node); | |
875 | timer->enabled = 0; | |
876 | if (timer->task.func) | |
877 | timer->task.func(timer->task.private_data); | |
878 | ||
879 | /* Re-add/fwd periodic timers */ | |
880 | if (ktime_to_ns(timer->period)) { | |
881 | timer->node.expires = ktime_add(timer->node.expires, | |
882 | timer->period); | |
883 | timer->enabled = 1; | |
884 | timerqueue_add(&rtc->timerqueue, &timer->node); | |
885 | } | |
886 | } | |
887 | ||
888 | /* Set next alarm */ | |
889 | if (next) { | |
890 | struct rtc_wkalrm alarm; | |
891 | int err; | |
892 | alarm.time = rtc_ktime_to_tm(next->expires); | |
893 | alarm.enabled = 1; | |
894 | err = __rtc_set_alarm(rtc, &alarm); | |
895 | if (err == -ETIME) | |
896 | goto again; | |
41c7f742 RV |
897 | } else |
898 | rtc_alarm_disable(rtc); | |
6610e089 | 899 | |
14d0e347 | 900 | pm_relax(rtc->dev.parent); |
6610e089 JS |
901 | mutex_unlock(&rtc->ops_lock); |
902 | } | |
903 | ||
904 | ||
96c8f06a | 905 | /* rtc_timer_init - Initializes an rtc_timer |
6610e089 JS |
906 | * @timer: timer to be intiialized |
907 | * @f: function pointer to be called when timer fires | |
908 | * @data: private data passed to function pointer | |
909 | * | |
910 | * Kernel interface to initializing an rtc_timer. | |
911 | */ | |
3ff2e13c | 912 | void rtc_timer_init(struct rtc_timer *timer, void (*f)(void *p), void *data) |
6610e089 JS |
913 | { |
914 | timerqueue_init(&timer->node); | |
915 | timer->enabled = 0; | |
916 | timer->task.func = f; | |
917 | timer->task.private_data = data; | |
918 | } | |
919 | ||
96c8f06a | 920 | /* rtc_timer_start - Sets an rtc_timer to fire in the future |
6610e089 JS |
921 | * @ rtc: rtc device to be used |
922 | * @ timer: timer being set | |
923 | * @ expires: time at which to expire the timer | |
924 | * @ period: period that the timer will recur | |
925 | * | |
926 | * Kernel interface to set an rtc_timer | |
927 | */ | |
3ff2e13c | 928 | int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer *timer, |
6610e089 JS |
929 | ktime_t expires, ktime_t period) |
930 | { | |
931 | int ret = 0; | |
932 | mutex_lock(&rtc->ops_lock); | |
933 | if (timer->enabled) | |
96c8f06a | 934 | rtc_timer_remove(rtc, timer); |
6610e089 JS |
935 | |
936 | timer->node.expires = expires; | |
937 | timer->period = period; | |
938 | ||
aa0be0f4 | 939 | ret = rtc_timer_enqueue(rtc, timer); |
6610e089 JS |
940 | |
941 | mutex_unlock(&rtc->ops_lock); | |
942 | return ret; | |
943 | } | |
944 | ||
96c8f06a | 945 | /* rtc_timer_cancel - Stops an rtc_timer |
6610e089 JS |
946 | * @ rtc: rtc device to be used |
947 | * @ timer: timer being set | |
948 | * | |
949 | * Kernel interface to cancel an rtc_timer | |
950 | */ | |
3ff2e13c | 951 | int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer *timer) |
6610e089 JS |
952 | { |
953 | int ret = 0; | |
954 | mutex_lock(&rtc->ops_lock); | |
955 | if (timer->enabled) | |
96c8f06a | 956 | rtc_timer_remove(rtc, timer); |
6610e089 JS |
957 | mutex_unlock(&rtc->ops_lock); |
958 | return ret; | |
959 | } | |
960 | ||
961 |