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 AZ |
74 | |
75 | mutex_unlock(&rtc->ops_lock); | |
5f9679d2 N |
76 | /* A timer might have just expired */ |
77 | schedule_work(&rtc->irqwork); | |
0c86edc0 AZ |
78 | return err; |
79 | } | |
80 | EXPORT_SYMBOL_GPL(rtc_set_time); | |
81 | ||
ab6a2d70 | 82 | int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs) |
0c86edc0 AZ |
83 | { |
84 | int err; | |
0c86edc0 AZ |
85 | |
86 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
87 | if (err) | |
b68bb263 | 88 | return err; |
0c86edc0 AZ |
89 | |
90 | if (!rtc->ops) | |
91 | err = -ENODEV; | |
92 | else if (rtc->ops->set_mmss) | |
cd966209 | 93 | err = rtc->ops->set_mmss(rtc->dev.parent, secs); |
0c86edc0 AZ |
94 | else if (rtc->ops->read_time && rtc->ops->set_time) { |
95 | struct rtc_time new, old; | |
96 | ||
cd966209 | 97 | err = rtc->ops->read_time(rtc->dev.parent, &old); |
0c86edc0 AZ |
98 | if (err == 0) { |
99 | rtc_time_to_tm(secs, &new); | |
100 | ||
101 | /* | |
102 | * avoid writing when we're going to change the day of | |
103 | * the month. We will retry in the next minute. This | |
104 | * basically means that if the RTC must not drift | |
105 | * by more than 1 minute in 11 minutes. | |
106 | */ | |
107 | if (!((old.tm_hour == 23 && old.tm_min == 59) || | |
108 | (new.tm_hour == 23 && new.tm_min == 59))) | |
cd966209 | 109 | err = rtc->ops->set_time(rtc->dev.parent, |
ab6a2d70 | 110 | &new); |
0c86edc0 AZ |
111 | } |
112 | } | |
113 | else | |
114 | err = -EINVAL; | |
115 | ||
116 | mutex_unlock(&rtc->ops_lock); | |
5f9679d2 N |
117 | /* A timer might have just expired */ |
118 | schedule_work(&rtc->irqwork); | |
0c86edc0 AZ |
119 | |
120 | return err; | |
121 | } | |
122 | EXPORT_SYMBOL_GPL(rtc_set_mmss); | |
123 | ||
f44f7f96 JS |
124 | static int rtc_read_alarm_internal(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
125 | { | |
126 | int err; | |
127 | ||
128 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
129 | if (err) | |
130 | return err; | |
131 | ||
132 | if (rtc->ops == NULL) | |
133 | err = -ENODEV; | |
134 | else if (!rtc->ops->read_alarm) | |
135 | err = -EINVAL; | |
136 | else { | |
137 | memset(alarm, 0, sizeof(struct rtc_wkalrm)); | |
138 | err = rtc->ops->read_alarm(rtc->dev.parent, alarm); | |
139 | } | |
140 | ||
141 | mutex_unlock(&rtc->ops_lock); | |
142 | return err; | |
143 | } | |
144 | ||
145 | int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) | |
146 | { | |
147 | int err; | |
148 | struct rtc_time before, now; | |
149 | int first_time = 1; | |
150 | unsigned long t_now, t_alm; | |
151 | enum { none, day, month, year } missing = none; | |
152 | unsigned days; | |
153 | ||
154 | /* The lower level RTC driver may return -1 in some fields, | |
155 | * creating invalid alarm->time values, for reasons like: | |
156 | * | |
157 | * - The hardware may not be capable of filling them in; | |
158 | * many alarms match only on time-of-day fields, not | |
159 | * day/month/year calendar data. | |
160 | * | |
161 | * - Some hardware uses illegal values as "wildcard" match | |
162 | * values, which non-Linux firmware (like a BIOS) may try | |
163 | * to set up as e.g. "alarm 15 minutes after each hour". | |
164 | * Linux uses only oneshot alarms. | |
165 | * | |
166 | * When we see that here, we deal with it by using values from | |
167 | * a current RTC timestamp for any missing (-1) values. The | |
168 | * RTC driver prevents "periodic alarm" modes. | |
169 | * | |
170 | * But this can be racey, because some fields of the RTC timestamp | |
171 | * may have wrapped in the interval since we read the RTC alarm, | |
172 | * which would lead to us inserting inconsistent values in place | |
173 | * of the -1 fields. | |
174 | * | |
175 | * Reading the alarm and timestamp in the reverse sequence | |
176 | * would have the same race condition, and not solve the issue. | |
177 | * | |
178 | * So, we must first read the RTC timestamp, | |
179 | * then read the RTC alarm value, | |
180 | * and then read a second RTC timestamp. | |
181 | * | |
182 | * If any fields of the second timestamp have changed | |
183 | * when compared with the first timestamp, then we know | |
184 | * our timestamp may be inconsistent with that used by | |
185 | * the low-level rtc_read_alarm_internal() function. | |
186 | * | |
187 | * So, when the two timestamps disagree, we just loop and do | |
188 | * the process again to get a fully consistent set of values. | |
189 | * | |
190 | * This could all instead be done in the lower level driver, | |
191 | * but since more than one lower level RTC implementation needs it, | |
192 | * then it's probably best best to do it here instead of there.. | |
193 | */ | |
194 | ||
195 | /* Get the "before" timestamp */ | |
196 | err = rtc_read_time(rtc, &before); | |
197 | if (err < 0) | |
198 | return err; | |
199 | do { | |
200 | if (!first_time) | |
201 | memcpy(&before, &now, sizeof(struct rtc_time)); | |
202 | first_time = 0; | |
203 | ||
204 | /* get the RTC alarm values, which may be incomplete */ | |
205 | err = rtc_read_alarm_internal(rtc, alarm); | |
206 | if (err) | |
207 | return err; | |
208 | ||
209 | /* full-function RTCs won't have such missing fields */ | |
210 | if (rtc_valid_tm(&alarm->time) == 0) | |
211 | return 0; | |
212 | ||
213 | /* get the "after" timestamp, to detect wrapped fields */ | |
214 | err = rtc_read_time(rtc, &now); | |
215 | if (err < 0) | |
216 | return err; | |
217 | ||
218 | /* note that tm_sec is a "don't care" value here: */ | |
219 | } while ( before.tm_min != now.tm_min | |
220 | || before.tm_hour != now.tm_hour | |
221 | || before.tm_mon != now.tm_mon | |
222 | || before.tm_year != now.tm_year); | |
223 | ||
224 | /* Fill in the missing alarm fields using the timestamp; we | |
225 | * know there's at least one since alarm->time is invalid. | |
226 | */ | |
227 | if (alarm->time.tm_sec == -1) | |
228 | alarm->time.tm_sec = now.tm_sec; | |
229 | if (alarm->time.tm_min == -1) | |
230 | alarm->time.tm_min = now.tm_min; | |
231 | if (alarm->time.tm_hour == -1) | |
232 | alarm->time.tm_hour = now.tm_hour; | |
233 | ||
234 | /* For simplicity, only support date rollover for now */ | |
e74a8f2e | 235 | if (alarm->time.tm_mday < 1 || alarm->time.tm_mday > 31) { |
f44f7f96 JS |
236 | alarm->time.tm_mday = now.tm_mday; |
237 | missing = day; | |
238 | } | |
e74a8f2e | 239 | if ((unsigned)alarm->time.tm_mon >= 12) { |
f44f7f96 JS |
240 | alarm->time.tm_mon = now.tm_mon; |
241 | if (missing == none) | |
242 | missing = month; | |
243 | } | |
244 | if (alarm->time.tm_year == -1) { | |
245 | alarm->time.tm_year = now.tm_year; | |
246 | if (missing == none) | |
247 | missing = year; | |
248 | } | |
249 | ||
250 | /* with luck, no rollover is needed */ | |
251 | rtc_tm_to_time(&now, &t_now); | |
252 | rtc_tm_to_time(&alarm->time, &t_alm); | |
253 | if (t_now < t_alm) | |
254 | goto done; | |
255 | ||
256 | switch (missing) { | |
257 | ||
258 | /* 24 hour rollover ... if it's now 10am Monday, an alarm that | |
259 | * that will trigger at 5am will do so at 5am Tuesday, which | |
260 | * could also be in the next month or year. This is a common | |
261 | * case, especially for PCs. | |
262 | */ | |
263 | case day: | |
264 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "day"); | |
265 | t_alm += 24 * 60 * 60; | |
266 | rtc_time_to_tm(t_alm, &alarm->time); | |
267 | break; | |
268 | ||
269 | /* Month rollover ... if it's the 31th, an alarm on the 3rd will | |
270 | * be next month. An alarm matching on the 30th, 29th, or 28th | |
271 | * may end up in the month after that! Many newer PCs support | |
272 | * this type of alarm. | |
273 | */ | |
274 | case month: | |
275 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "month"); | |
276 | do { | |
277 | if (alarm->time.tm_mon < 11) | |
278 | alarm->time.tm_mon++; | |
279 | else { | |
280 | alarm->time.tm_mon = 0; | |
281 | alarm->time.tm_year++; | |
282 | } | |
283 | days = rtc_month_days(alarm->time.tm_mon, | |
284 | alarm->time.tm_year); | |
285 | } while (days < alarm->time.tm_mday); | |
286 | break; | |
287 | ||
288 | /* Year rollover ... easy except for leap years! */ | |
289 | case year: | |
290 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "year"); | |
291 | do { | |
292 | alarm->time.tm_year++; | |
293 | } while (rtc_valid_tm(&alarm->time) != 0); | |
294 | break; | |
295 | ||
296 | default: | |
297 | dev_warn(&rtc->dev, "alarm rollover not handled\n"); | |
298 | } | |
299 | ||
300 | done: | |
301 | return 0; | |
302 | } | |
303 | ||
6610e089 | 304 | int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0c86edc0 | 305 | { |
6fa3eb70 S |
306 | #ifdef RTC_LEGACY_ALARM_IMPL |
307 | return __rtc_read_alarm(rtc, alarm); | |
308 | #else | |
0c86edc0 | 309 | int err; |
0c86edc0 AZ |
310 | |
311 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
312 | if (err) | |
b68bb263 | 313 | return err; |
d5553a55 JS |
314 | if (rtc->ops == NULL) |
315 | err = -ENODEV; | |
316 | else if (!rtc->ops->read_alarm) | |
317 | err = -EINVAL; | |
318 | else { | |
319 | memset(alarm, 0, sizeof(struct rtc_wkalrm)); | |
320 | alarm->enabled = rtc->aie_timer.enabled; | |
6610e089 | 321 | alarm->time = rtc_ktime_to_tm(rtc->aie_timer.node.expires); |
d5553a55 | 322 | } |
0c86edc0 | 323 | mutex_unlock(&rtc->ops_lock); |
6610e089 | 324 | |
d5553a55 | 325 | return err; |
6fa3eb70 | 326 | #endif |
0c86edc0 | 327 | } |
6610e089 | 328 | EXPORT_SYMBOL_GPL(rtc_read_alarm); |
0e36a9a4 | 329 | |
d576fe49 | 330 | static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0e36a9a4 | 331 | { |
6fa3eb70 S |
332 | #ifdef RTC_LEGACY_ALARM_IMPL |
333 | WARN(1, "__rtc_set_alarm() is not supported!!\n"); | |
334 | return -EPERM; | |
335 | #else | |
6610e089 JS |
336 | struct rtc_time tm; |
337 | long now, scheduled; | |
0e36a9a4 | 338 | int err; |
0e36a9a4 | 339 | |
6610e089 JS |
340 | err = rtc_valid_tm(&alarm->time); |
341 | if (err) | |
0e36a9a4 | 342 | return err; |
6610e089 | 343 | rtc_tm_to_time(&alarm->time, &scheduled); |
a01cc657 | 344 | |
6610e089 JS |
345 | /* Make sure we're not setting alarms in the past */ |
346 | err = __rtc_read_time(rtc, &tm); | |
347 | rtc_tm_to_time(&tm, &now); | |
348 | if (scheduled <= now) | |
349 | return -ETIME; | |
350 | /* | |
351 | * XXX - We just checked to make sure the alarm time is not | |
352 | * in the past, but there is still a race window where if | |
353 | * the is alarm set for the next second and the second ticks | |
354 | * over right here, before we set the alarm. | |
a01cc657 | 355 | */ |
a01cc657 | 356 | |
157e8bf8 LT |
357 | if (!rtc->ops) |
358 | err = -ENODEV; | |
359 | else if (!rtc->ops->set_alarm) | |
360 | err = -EINVAL; | |
361 | else | |
362 | err = rtc->ops->set_alarm(rtc->dev.parent, alarm); | |
363 | ||
364 | return err; | |
6fa3eb70 | 365 | #endif |
0e36a9a4 | 366 | } |
0c86edc0 | 367 | |
ab6a2d70 | 368 | int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0c86edc0 AZ |
369 | { |
370 | int err; | |
0c86edc0 | 371 | |
f8245c26 DB |
372 | err = rtc_valid_tm(&alarm->time); |
373 | if (err != 0) | |
374 | return err; | |
375 | ||
0c86edc0 AZ |
376 | err = mutex_lock_interruptible(&rtc->ops_lock); |
377 | if (err) | |
b68bb263 | 378 | return err; |
6fa3eb70 S |
379 | #ifdef RTC_LEGACY_ALARM_IMPL |
380 | if (!rtc->ops) | |
381 | err = -ENODEV; | |
382 | else if (!rtc->ops->set_alarm) | |
383 | err = -EINVAL; | |
384 | else | |
385 | err = rtc->ops->set_alarm(rtc->dev.parent, alarm); | |
386 | #else | |
387 | ||
6610e089 | 388 | if (rtc->aie_timer.enabled) { |
96c8f06a | 389 | rtc_timer_remove(rtc, &rtc->aie_timer); |
6610e089 JS |
390 | } |
391 | rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time); | |
392 | rtc->aie_timer.period = ktime_set(0, 0); | |
393 | if (alarm->enabled) { | |
aa0be0f4 | 394 | err = rtc_timer_enqueue(rtc, &rtc->aie_timer); |
6610e089 | 395 | } |
6fa3eb70 | 396 | #endif |
0c86edc0 | 397 | mutex_unlock(&rtc->ops_lock); |
aa0be0f4 | 398 | return err; |
0c86edc0 AZ |
399 | } |
400 | EXPORT_SYMBOL_GPL(rtc_set_alarm); | |
401 | ||
6fa3eb70 S |
402 | int rtc_set_alarm_poweron(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
403 | { | |
404 | int err; | |
405 | ||
406 | err = rtc_valid_tm(&alarm->time); | |
407 | if (err != 0) | |
408 | return err; | |
409 | ||
410 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
411 | if (err) | |
412 | return err; | |
413 | ||
414 | if (!rtc->ops) | |
415 | err = -ENODEV; | |
416 | else if (!rtc->ops->set_alarm) | |
417 | err = -EINVAL; | |
418 | else | |
419 | err = rtc->ops->set_alarm(rtc->dev.parent, alarm); | |
420 | ||
421 | mutex_unlock(&rtc->ops_lock); | |
422 | return err; | |
423 | } | |
424 | EXPORT_SYMBOL_GPL(rtc_set_alarm_poweron); | |
425 | ||
f6d5b331 JS |
426 | /* Called once per device from rtc_device_register */ |
427 | int rtc_initialize_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) | |
428 | { | |
6fa3eb70 S |
429 | #ifdef RTC_LEGACY_ALARM_IMPL |
430 | return 0; | |
431 | #else | |
f6d5b331 | 432 | int err; |
bd729d72 | 433 | struct rtc_time now; |
f6d5b331 JS |
434 | |
435 | err = rtc_valid_tm(&alarm->time); | |
436 | if (err != 0) | |
437 | return err; | |
438 | ||
bd729d72 JS |
439 | err = rtc_read_time(rtc, &now); |
440 | if (err) | |
441 | return err; | |
442 | ||
f6d5b331 JS |
443 | err = mutex_lock_interruptible(&rtc->ops_lock); |
444 | if (err) | |
445 | return err; | |
446 | ||
447 | rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time); | |
448 | rtc->aie_timer.period = ktime_set(0, 0); | |
bd729d72 JS |
449 | |
450 | /* Alarm has to be enabled & in the futrure for us to enqueue it */ | |
451 | if (alarm->enabled && (rtc_tm_to_ktime(now).tv64 < | |
452 | rtc->aie_timer.node.expires.tv64)) { | |
453 | ||
f6d5b331 JS |
454 | rtc->aie_timer.enabled = 1; |
455 | timerqueue_add(&rtc->timerqueue, &rtc->aie_timer.node); | |
456 | } | |
457 | mutex_unlock(&rtc->ops_lock); | |
458 | return err; | |
6fa3eb70 | 459 | #endif |
f6d5b331 JS |
460 | } |
461 | EXPORT_SYMBOL_GPL(rtc_initialize_alarm); | |
462 | ||
463 | ||
464 | ||
099e6576 AZ |
465 | int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled) |
466 | { | |
467 | int err = mutex_lock_interruptible(&rtc->ops_lock); | |
468 | if (err) | |
469 | return err; | |
470 | ||
6610e089 | 471 | if (rtc->aie_timer.enabled != enabled) { |
aa0be0f4 JS |
472 | if (enabled) |
473 | err = rtc_timer_enqueue(rtc, &rtc->aie_timer); | |
474 | else | |
96c8f06a | 475 | rtc_timer_remove(rtc, &rtc->aie_timer); |
6610e089 JS |
476 | } |
477 | ||
aa0be0f4 | 478 | if (err) |
516373b8 UKK |
479 | /* nothing */; |
480 | else if (!rtc->ops) | |
099e6576 AZ |
481 | err = -ENODEV; |
482 | else if (!rtc->ops->alarm_irq_enable) | |
483 | err = -EINVAL; | |
484 | else | |
485 | err = rtc->ops->alarm_irq_enable(rtc->dev.parent, enabled); | |
486 | ||
487 | mutex_unlock(&rtc->ops_lock); | |
488 | return err; | |
489 | } | |
490 | EXPORT_SYMBOL_GPL(rtc_alarm_irq_enable); | |
491 | ||
492 | int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled) | |
493 | { | |
494 | int err = mutex_lock_interruptible(&rtc->ops_lock); | |
495 | if (err) | |
496 | return err; | |
497 | ||
456d66ec JS |
498 | #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL |
499 | if (enabled == 0 && rtc->uie_irq_active) { | |
500 | mutex_unlock(&rtc->ops_lock); | |
501 | return rtc_dev_update_irq_enable_emul(rtc, 0); | |
502 | } | |
503 | #endif | |
6610e089 JS |
504 | /* make sure we're changing state */ |
505 | if (rtc->uie_rtctimer.enabled == enabled) | |
506 | goto out; | |
507 | ||
4a649903 JS |
508 | if (rtc->uie_unsupported) { |
509 | err = -EINVAL; | |
510 | goto out; | |
511 | } | |
512 | ||
6610e089 JS |
513 | if (enabled) { |
514 | struct rtc_time tm; | |
515 | ktime_t now, onesec; | |
516 | ||
517 | __rtc_read_time(rtc, &tm); | |
518 | onesec = ktime_set(1, 0); | |
519 | now = rtc_tm_to_ktime(tm); | |
520 | rtc->uie_rtctimer.node.expires = ktime_add(now, onesec); | |
521 | rtc->uie_rtctimer.period = ktime_set(1, 0); | |
aa0be0f4 JS |
522 | err = rtc_timer_enqueue(rtc, &rtc->uie_rtctimer); |
523 | } else | |
96c8f06a | 524 | rtc_timer_remove(rtc, &rtc->uie_rtctimer); |
099e6576 | 525 | |
6610e089 | 526 | out: |
099e6576 | 527 | mutex_unlock(&rtc->ops_lock); |
456d66ec JS |
528 | #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL |
529 | /* | |
530 | * Enable emulation if the driver did not provide | |
531 | * the update_irq_enable function pointer or if returned | |
532 | * -EINVAL to signal that it has been configured without | |
533 | * interrupts or that are not available at the moment. | |
534 | */ | |
535 | if (err == -EINVAL) | |
536 | err = rtc_dev_update_irq_enable_emul(rtc, enabled); | |
537 | #endif | |
099e6576 | 538 | return err; |
6610e089 | 539 | |
099e6576 AZ |
540 | } |
541 | EXPORT_SYMBOL_GPL(rtc_update_irq_enable); | |
542 | ||
6610e089 | 543 | |
d728b1e6 | 544 | /** |
6610e089 JS |
545 | * rtc_handle_legacy_irq - AIE, UIE and PIE event hook |
546 | * @rtc: pointer to the rtc device | |
547 | * | |
548 | * This function is called when an AIE, UIE or PIE mode interrupt | |
25985edc | 549 | * has occurred (or been emulated). |
6610e089 JS |
550 | * |
551 | * Triggers the registered irq_task function callback. | |
d728b1e6 | 552 | */ |
456d66ec | 553 | void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode) |
0c86edc0 | 554 | { |
e6229bec AN |
555 | unsigned long flags; |
556 | ||
6610e089 | 557 | /* mark one irq of the appropriate mode */ |
e6229bec | 558 | spin_lock_irqsave(&rtc->irq_lock, flags); |
6610e089 | 559 | rtc->irq_data = (rtc->irq_data + (num << 8)) | (RTC_IRQF|mode); |
e6229bec | 560 | spin_unlock_irqrestore(&rtc->irq_lock, flags); |
0c86edc0 | 561 | |
6610e089 | 562 | /* call the task func */ |
e6229bec | 563 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
564 | if (rtc->irq_task) |
565 | rtc->irq_task->func(rtc->irq_task->private_data); | |
e6229bec | 566 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
567 | |
568 | wake_up_interruptible(&rtc->irq_queue); | |
569 | kill_fasync(&rtc->async_queue, SIGIO, POLL_IN); | |
570 | } | |
6610e089 JS |
571 | |
572 | ||
573 | /** | |
574 | * rtc_aie_update_irq - AIE mode rtctimer hook | |
575 | * @private: pointer to the rtc_device | |
576 | * | |
577 | * This functions is called when the aie_timer expires. | |
578 | */ | |
579 | void rtc_aie_update_irq(void *private) | |
580 | { | |
581 | struct rtc_device *rtc = (struct rtc_device *)private; | |
582 | rtc_handle_legacy_irq(rtc, 1, RTC_AF); | |
583 | } | |
584 | ||
585 | ||
586 | /** | |
587 | * rtc_uie_update_irq - UIE mode rtctimer hook | |
588 | * @private: pointer to the rtc_device | |
589 | * | |
590 | * This functions is called when the uie_timer expires. | |
591 | */ | |
592 | void rtc_uie_update_irq(void *private) | |
593 | { | |
594 | struct rtc_device *rtc = (struct rtc_device *)private; | |
595 | rtc_handle_legacy_irq(rtc, 1, RTC_UF); | |
596 | } | |
597 | ||
598 | ||
599 | /** | |
600 | * rtc_pie_update_irq - PIE mode hrtimer hook | |
601 | * @timer: pointer to the pie mode hrtimer | |
602 | * | |
603 | * This function is used to emulate PIE mode interrupts | |
604 | * using an hrtimer. This function is called when the periodic | |
605 | * hrtimer expires. | |
606 | */ | |
607 | enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer) | |
608 | { | |
609 | struct rtc_device *rtc; | |
610 | ktime_t period; | |
611 | int count; | |
612 | rtc = container_of(timer, struct rtc_device, pie_timer); | |
613 | ||
614 | period = ktime_set(0, NSEC_PER_SEC/rtc->irq_freq); | |
615 | count = hrtimer_forward_now(timer, period); | |
616 | ||
617 | rtc_handle_legacy_irq(rtc, count, RTC_PF); | |
618 | ||
619 | return HRTIMER_RESTART; | |
620 | } | |
621 | ||
622 | /** | |
623 | * rtc_update_irq - Triggered when a RTC interrupt occurs. | |
624 | * @rtc: the rtc device | |
625 | * @num: how many irqs are being reported (usually one) | |
626 | * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF | |
627 | * Context: any | |
628 | */ | |
629 | void rtc_update_irq(struct rtc_device *rtc, | |
630 | unsigned long num, unsigned long events) | |
631 | { | |
7523ceed | 632 | pm_stay_awake(rtc->dev.parent); |
6610e089 JS |
633 | schedule_work(&rtc->irqwork); |
634 | } | |
0c86edc0 AZ |
635 | EXPORT_SYMBOL_GPL(rtc_update_irq); |
636 | ||
9f3b795a | 637 | static int __rtc_match(struct device *dev, const void *data) |
71da8905 | 638 | { |
9f3b795a | 639 | const char *name = data; |
71da8905 | 640 | |
d4afc76c | 641 | if (strcmp(dev_name(dev), name) == 0) |
71da8905 DY |
642 | return 1; |
643 | return 0; | |
644 | } | |
645 | ||
9f3b795a | 646 | struct rtc_device *rtc_class_open(const char *name) |
0c86edc0 | 647 | { |
cd966209 | 648 | struct device *dev; |
ab6a2d70 | 649 | struct rtc_device *rtc = NULL; |
0c86edc0 | 650 | |
695794ae | 651 | dev = class_find_device(rtc_class, NULL, name, __rtc_match); |
71da8905 DY |
652 | if (dev) |
653 | rtc = to_rtc_device(dev); | |
0c86edc0 | 654 | |
ab6a2d70 DB |
655 | if (rtc) { |
656 | if (!try_module_get(rtc->owner)) { | |
cd966209 | 657 | put_device(dev); |
ab6a2d70 DB |
658 | rtc = NULL; |
659 | } | |
0c86edc0 | 660 | } |
0c86edc0 | 661 | |
ab6a2d70 | 662 | return rtc; |
0c86edc0 AZ |
663 | } |
664 | EXPORT_SYMBOL_GPL(rtc_class_open); | |
665 | ||
ab6a2d70 | 666 | void rtc_class_close(struct rtc_device *rtc) |
0c86edc0 | 667 | { |
ab6a2d70 | 668 | module_put(rtc->owner); |
cd966209 | 669 | put_device(&rtc->dev); |
0c86edc0 AZ |
670 | } |
671 | EXPORT_SYMBOL_GPL(rtc_class_close); | |
672 | ||
ab6a2d70 | 673 | int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task) |
0c86edc0 AZ |
674 | { |
675 | int retval = -EBUSY; | |
0c86edc0 AZ |
676 | |
677 | if (task == NULL || task->func == NULL) | |
678 | return -EINVAL; | |
679 | ||
d691eb90 | 680 | /* Cannot register while the char dev is in use */ |
372a302e | 681 | if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags)) |
d691eb90 AZ |
682 | return -EBUSY; |
683 | ||
d728b1e6 | 684 | spin_lock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
685 | if (rtc->irq_task == NULL) { |
686 | rtc->irq_task = task; | |
687 | retval = 0; | |
688 | } | |
d728b1e6 | 689 | spin_unlock_irq(&rtc->irq_task_lock); |
0c86edc0 | 690 | |
372a302e | 691 | clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags); |
d691eb90 | 692 | |
0c86edc0 AZ |
693 | return retval; |
694 | } | |
695 | EXPORT_SYMBOL_GPL(rtc_irq_register); | |
696 | ||
ab6a2d70 | 697 | void rtc_irq_unregister(struct rtc_device *rtc, struct rtc_task *task) |
0c86edc0 | 698 | { |
d728b1e6 | 699 | spin_lock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
700 | if (rtc->irq_task == task) |
701 | rtc->irq_task = NULL; | |
d728b1e6 | 702 | spin_unlock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
703 | } |
704 | EXPORT_SYMBOL_GPL(rtc_irq_unregister); | |
705 | ||
3c8bb90e TG |
706 | static int rtc_update_hrtimer(struct rtc_device *rtc, int enabled) |
707 | { | |
708 | /* | |
709 | * We always cancel the timer here first, because otherwise | |
710 | * we could run into BUG_ON(timer->state != HRTIMER_STATE_CALLBACK); | |
711 | * when we manage to start the timer before the callback | |
712 | * returns HRTIMER_RESTART. | |
713 | * | |
714 | * We cannot use hrtimer_cancel() here as a running callback | |
715 | * could be blocked on rtc->irq_task_lock and hrtimer_cancel() | |
716 | * would spin forever. | |
717 | */ | |
718 | if (hrtimer_try_to_cancel(&rtc->pie_timer) < 0) | |
719 | return -1; | |
720 | ||
721 | if (enabled) { | |
722 | ktime_t period = ktime_set(0, NSEC_PER_SEC / rtc->irq_freq); | |
723 | ||
724 | hrtimer_start(&rtc->pie_timer, period, HRTIMER_MODE_REL); | |
725 | } | |
726 | return 0; | |
727 | } | |
728 | ||
97144c67 DB |
729 | /** |
730 | * rtc_irq_set_state - enable/disable 2^N Hz periodic IRQs | |
731 | * @rtc: the rtc device | |
732 | * @task: currently registered with rtc_irq_register() | |
733 | * @enabled: true to enable periodic IRQs | |
734 | * Context: any | |
735 | * | |
736 | * Note that rtc_irq_set_freq() should previously have been used to | |
737 | * specify the desired frequency of periodic IRQ task->func() callbacks. | |
738 | */ | |
ab6a2d70 | 739 | int rtc_irq_set_state(struct rtc_device *rtc, struct rtc_task *task, int enabled) |
0c86edc0 AZ |
740 | { |
741 | int err = 0; | |
742 | unsigned long flags; | |
0c86edc0 | 743 | |
3c8bb90e | 744 | retry: |
0c86edc0 | 745 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
d691eb90 AZ |
746 | if (rtc->irq_task != NULL && task == NULL) |
747 | err = -EBUSY; | |
0c86edc0 | 748 | if (rtc->irq_task != task) |
d691eb90 | 749 | err = -EACCES; |
3c8bb90e TG |
750 | if (!err) { |
751 | if (rtc_update_hrtimer(rtc, enabled) < 0) { | |
752 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); | |
753 | cpu_relax(); | |
754 | goto retry; | |
755 | } | |
756 | rtc->pie_enabled = enabled; | |
6610e089 | 757 | } |
6610e089 | 758 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
759 | return err; |
760 | } | |
761 | EXPORT_SYMBOL_GPL(rtc_irq_set_state); | |
762 | ||
97144c67 DB |
763 | /** |
764 | * rtc_irq_set_freq - set 2^N Hz periodic IRQ frequency for IRQ | |
765 | * @rtc: the rtc device | |
766 | * @task: currently registered with rtc_irq_register() | |
767 | * @freq: positive frequency with which task->func() will be called | |
768 | * Context: any | |
769 | * | |
770 | * Note that rtc_irq_set_state() is used to enable or disable the | |
771 | * periodic IRQs. | |
772 | */ | |
ab6a2d70 | 773 | int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq) |
0c86edc0 | 774 | { |
56f10c63 | 775 | int err = 0; |
0c86edc0 | 776 | unsigned long flags; |
0c86edc0 | 777 | |
6e7a333e | 778 | if (freq <= 0 || freq > RTC_MAX_FREQ) |
83a06bf5 | 779 | return -EINVAL; |
3c8bb90e | 780 | retry: |
0c86edc0 | 781 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
d691eb90 AZ |
782 | if (rtc->irq_task != NULL && task == NULL) |
783 | err = -EBUSY; | |
0c86edc0 | 784 | if (rtc->irq_task != task) |
d691eb90 | 785 | err = -EACCES; |
3c8bb90e | 786 | if (!err) { |
6610e089 | 787 | rtc->irq_freq = freq; |
3c8bb90e TG |
788 | if (rtc->pie_enabled && rtc_update_hrtimer(rtc, 1) < 0) { |
789 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); | |
790 | cpu_relax(); | |
791 | goto retry; | |
6610e089 | 792 | } |
0c86edc0 | 793 | } |
6610e089 | 794 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
795 | return err; |
796 | } | |
2601a464 | 797 | EXPORT_SYMBOL_GPL(rtc_irq_set_freq); |
6610e089 JS |
798 | |
799 | /** | |
96c8f06a | 800 | * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue |
6610e089 JS |
801 | * @rtc rtc device |
802 | * @timer timer being added. | |
803 | * | |
804 | * Enqueues a timer onto the rtc devices timerqueue and sets | |
805 | * the next alarm event appropriately. | |
806 | * | |
aa0be0f4 JS |
807 | * Sets the enabled bit on the added timer. |
808 | * | |
6610e089 JS |
809 | * Must hold ops_lock for proper serialization of timerqueue |
810 | */ | |
aa0be0f4 | 811 | static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) |
6610e089 | 812 | { |
296a1ab2 CIK |
813 | struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue); |
814 | struct rtc_time tm; | |
815 | ktime_t now; | |
816 | ||
aa0be0f4 | 817 | timer->enabled = 1; |
296a1ab2 CIK |
818 | __rtc_read_time(rtc, &tm); |
819 | now = rtc_tm_to_ktime(tm); | |
820 | ||
821 | /* Skip over expired timers */ | |
822 | while (next) { | |
823 | if (next->expires.tv64 >= now.tv64) | |
824 | break; | |
825 | next = timerqueue_iterate_next(next); | |
826 | } | |
827 | ||
6610e089 | 828 | timerqueue_add(&rtc->timerqueue, &timer->node); |
296a1ab2 | 829 | if (!next) { |
6610e089 JS |
830 | struct rtc_wkalrm alarm; |
831 | int err; | |
832 | alarm.time = rtc_ktime_to_tm(timer->node.expires); | |
833 | alarm.enabled = 1; | |
834 | err = __rtc_set_alarm(rtc, &alarm); | |
835 | if (err == -ETIME) | |
836 | schedule_work(&rtc->irqwork); | |
aa0be0f4 JS |
837 | else if (err) { |
838 | timerqueue_del(&rtc->timerqueue, &timer->node); | |
839 | timer->enabled = 0; | |
840 | return err; | |
841 | } | |
6610e089 | 842 | } |
aa0be0f4 | 843 | return 0; |
6610e089 JS |
844 | } |
845 | ||
41c7f742 RV |
846 | static void rtc_alarm_disable(struct rtc_device *rtc) |
847 | { | |
848 | if (!rtc->ops || !rtc->ops->alarm_irq_enable) | |
849 | return; | |
850 | ||
851 | rtc->ops->alarm_irq_enable(rtc->dev.parent, false); | |
852 | } | |
853 | ||
6610e089 | 854 | /** |
96c8f06a | 855 | * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue |
6610e089 JS |
856 | * @rtc rtc device |
857 | * @timer timer being removed. | |
858 | * | |
859 | * Removes a timer onto the rtc devices timerqueue and sets | |
860 | * the next alarm event appropriately. | |
861 | * | |
aa0be0f4 JS |
862 | * Clears the enabled bit on the removed timer. |
863 | * | |
6610e089 JS |
864 | * Must hold ops_lock for proper serialization of timerqueue |
865 | */ | |
aa0be0f4 | 866 | static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer) |
6610e089 JS |
867 | { |
868 | struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue); | |
869 | timerqueue_del(&rtc->timerqueue, &timer->node); | |
aa0be0f4 | 870 | timer->enabled = 0; |
6610e089 JS |
871 | if (next == &timer->node) { |
872 | struct rtc_wkalrm alarm; | |
873 | int err; | |
874 | next = timerqueue_getnext(&rtc->timerqueue); | |
41c7f742 RV |
875 | if (!next) { |
876 | rtc_alarm_disable(rtc); | |
6610e089 | 877 | return; |
41c7f742 | 878 | } |
6610e089 JS |
879 | alarm.time = rtc_ktime_to_tm(next->expires); |
880 | alarm.enabled = 1; | |
881 | err = __rtc_set_alarm(rtc, &alarm); | |
882 | if (err == -ETIME) | |
883 | schedule_work(&rtc->irqwork); | |
884 | } | |
885 | } | |
886 | ||
887 | /** | |
96c8f06a | 888 | * rtc_timer_do_work - Expires rtc timers |
6610e089 JS |
889 | * @rtc rtc device |
890 | * @timer timer being removed. | |
891 | * | |
892 | * Expires rtc timers. Reprograms next alarm event if needed. | |
893 | * Called via worktask. | |
894 | * | |
895 | * Serializes access to timerqueue via ops_lock mutex | |
896 | */ | |
96c8f06a | 897 | void rtc_timer_do_work(struct work_struct *work) |
6610e089 JS |
898 | { |
899 | struct rtc_timer *timer; | |
900 | struct timerqueue_node *next; | |
901 | ktime_t now; | |
902 | struct rtc_time tm; | |
903 | ||
904 | struct rtc_device *rtc = | |
905 | container_of(work, struct rtc_device, irqwork); | |
906 | ||
907 | mutex_lock(&rtc->ops_lock); | |
908 | again: | |
7523ceed | 909 | pm_relax(rtc->dev.parent); |
6610e089 JS |
910 | __rtc_read_time(rtc, &tm); |
911 | now = rtc_tm_to_ktime(tm); | |
912 | while ((next = timerqueue_getnext(&rtc->timerqueue))) { | |
913 | if (next->expires.tv64 > now.tv64) | |
914 | break; | |
915 | ||
916 | /* expire timer */ | |
917 | timer = container_of(next, struct rtc_timer, node); | |
918 | timerqueue_del(&rtc->timerqueue, &timer->node); | |
919 | timer->enabled = 0; | |
920 | if (timer->task.func) | |
921 | timer->task.func(timer->task.private_data); | |
922 | ||
923 | /* Re-add/fwd periodic timers */ | |
924 | if (ktime_to_ns(timer->period)) { | |
925 | timer->node.expires = ktime_add(timer->node.expires, | |
926 | timer->period); | |
927 | timer->enabled = 1; | |
928 | timerqueue_add(&rtc->timerqueue, &timer->node); | |
929 | } | |
930 | } | |
931 | ||
932 | /* Set next alarm */ | |
933 | if (next) { | |
934 | struct rtc_wkalrm alarm; | |
935 | int err; | |
936 | alarm.time = rtc_ktime_to_tm(next->expires); | |
937 | alarm.enabled = 1; | |
938 | err = __rtc_set_alarm(rtc, &alarm); | |
939 | if (err == -ETIME) | |
940 | goto again; | |
41c7f742 RV |
941 | } else |
942 | rtc_alarm_disable(rtc); | |
6610e089 JS |
943 | |
944 | mutex_unlock(&rtc->ops_lock); | |
945 | } | |
946 | ||
947 | ||
96c8f06a | 948 | /* rtc_timer_init - Initializes an rtc_timer |
6610e089 JS |
949 | * @timer: timer to be intiialized |
950 | * @f: function pointer to be called when timer fires | |
951 | * @data: private data passed to function pointer | |
952 | * | |
953 | * Kernel interface to initializing an rtc_timer. | |
954 | */ | |
96c8f06a | 955 | void rtc_timer_init(struct rtc_timer *timer, void (*f)(void* p), void* data) |
6610e089 JS |
956 | { |
957 | timerqueue_init(&timer->node); | |
958 | timer->enabled = 0; | |
959 | timer->task.func = f; | |
960 | timer->task.private_data = data; | |
961 | } | |
962 | ||
96c8f06a | 963 | /* rtc_timer_start - Sets an rtc_timer to fire in the future |
6610e089 JS |
964 | * @ rtc: rtc device to be used |
965 | * @ timer: timer being set | |
966 | * @ expires: time at which to expire the timer | |
967 | * @ period: period that the timer will recur | |
968 | * | |
969 | * Kernel interface to set an rtc_timer | |
970 | */ | |
96c8f06a | 971 | int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer* timer, |
6610e089 JS |
972 | ktime_t expires, ktime_t period) |
973 | { | |
974 | int ret = 0; | |
975 | mutex_lock(&rtc->ops_lock); | |
976 | if (timer->enabled) | |
96c8f06a | 977 | rtc_timer_remove(rtc, timer); |
6610e089 JS |
978 | |
979 | timer->node.expires = expires; | |
980 | timer->period = period; | |
981 | ||
aa0be0f4 | 982 | ret = rtc_timer_enqueue(rtc, timer); |
6610e089 JS |
983 | |
984 | mutex_unlock(&rtc->ops_lock); | |
985 | return ret; | |
986 | } | |
987 | ||
96c8f06a | 988 | /* rtc_timer_cancel - Stops an rtc_timer |
6610e089 JS |
989 | * @ rtc: rtc device to be used |
990 | * @ timer: timer being set | |
991 | * | |
992 | * Kernel interface to cancel an rtc_timer | |
993 | */ | |
96c8f06a | 994 | int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer* timer) |
6610e089 JS |
995 | { |
996 | int ret = 0; | |
997 | mutex_lock(&rtc->ops_lock); | |
998 | if (timer->enabled) | |
96c8f06a | 999 | rtc_timer_remove(rtc, timer); |
6610e089 JS |
1000 | mutex_unlock(&rtc->ops_lock); |
1001 | return ret; | |
1002 | } | |
1003 | ||
1004 |