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); |
16682c86 | 33 | if (err < 0) { |
d0bddb51 AK |
34 | dev_dbg(&rtc->dev, "read_time: fail to read: %d\n", |
35 | err); | |
16682c86 HG |
36 | return err; |
37 | } | |
38 | ||
39 | err = rtc_valid_tm(tm); | |
40 | if (err < 0) | |
d0bddb51 | 41 | dev_dbg(&rtc->dev, "read_time: rtc_time isn't valid\n"); |
0c86edc0 | 42 | } |
6610e089 JS |
43 | return err; |
44 | } | |
45 | ||
46 | int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm) | |
47 | { | |
48 | int err; | |
0c86edc0 | 49 | |
6610e089 JS |
50 | err = mutex_lock_interruptible(&rtc->ops_lock); |
51 | if (err) | |
52 | return err; | |
53 | ||
54 | err = __rtc_read_time(rtc, tm); | |
0c86edc0 AZ |
55 | mutex_unlock(&rtc->ops_lock); |
56 | return err; | |
57 | } | |
58 | EXPORT_SYMBOL_GPL(rtc_read_time); | |
59 | ||
ab6a2d70 | 60 | int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm) |
0c86edc0 AZ |
61 | { |
62 | int err; | |
0c86edc0 AZ |
63 | |
64 | err = rtc_valid_tm(tm); | |
65 | if (err != 0) | |
66 | return err; | |
67 | ||
68 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
69 | if (err) | |
b68bb263 | 70 | return err; |
0c86edc0 AZ |
71 | |
72 | if (!rtc->ops) | |
73 | err = -ENODEV; | |
bbccf83f | 74 | else if (rtc->ops->set_time) |
cd966209 | 75 | err = rtc->ops->set_time(rtc->dev.parent, tm); |
8e4ff1a8 XP |
76 | else if (rtc->ops->set_mmss64) { |
77 | time64_t secs64 = rtc_tm_to_time64(tm); | |
78 | ||
79 | err = rtc->ops->set_mmss64(rtc->dev.parent, secs64); | |
80 | } else if (rtc->ops->set_mmss) { | |
bc10aa93 XP |
81 | time64_t secs64 = rtc_tm_to_time64(tm); |
82 | err = rtc->ops->set_mmss(rtc->dev.parent, secs64); | |
bbccf83f AZ |
83 | } else |
84 | err = -EINVAL; | |
0c86edc0 | 85 | |
14d0e347 | 86 | pm_stay_awake(rtc->dev.parent); |
0c86edc0 | 87 | mutex_unlock(&rtc->ops_lock); |
5f9679d2 N |
88 | /* A timer might have just expired */ |
89 | schedule_work(&rtc->irqwork); | |
0c86edc0 AZ |
90 | return err; |
91 | } | |
92 | EXPORT_SYMBOL_GPL(rtc_set_time); | |
93 | ||
f44f7f96 JS |
94 | static int rtc_read_alarm_internal(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
95 | { | |
96 | int err; | |
97 | ||
98 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
99 | if (err) | |
100 | return err; | |
101 | ||
102 | if (rtc->ops == NULL) | |
103 | err = -ENODEV; | |
104 | else if (!rtc->ops->read_alarm) | |
105 | err = -EINVAL; | |
106 | else { | |
107 | memset(alarm, 0, sizeof(struct rtc_wkalrm)); | |
108 | err = rtc->ops->read_alarm(rtc->dev.parent, alarm); | |
109 | } | |
110 | ||
111 | mutex_unlock(&rtc->ops_lock); | |
112 | return err; | |
113 | } | |
114 | ||
115 | int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) | |
116 | { | |
117 | int err; | |
118 | struct rtc_time before, now; | |
119 | int first_time = 1; | |
bc10aa93 | 120 | time64_t t_now, t_alm; |
f44f7f96 JS |
121 | enum { none, day, month, year } missing = none; |
122 | unsigned days; | |
123 | ||
124 | /* The lower level RTC driver may return -1 in some fields, | |
125 | * creating invalid alarm->time values, for reasons like: | |
126 | * | |
127 | * - The hardware may not be capable of filling them in; | |
128 | * many alarms match only on time-of-day fields, not | |
129 | * day/month/year calendar data. | |
130 | * | |
131 | * - Some hardware uses illegal values as "wildcard" match | |
132 | * values, which non-Linux firmware (like a BIOS) may try | |
133 | * to set up as e.g. "alarm 15 minutes after each hour". | |
134 | * Linux uses only oneshot alarms. | |
135 | * | |
136 | * When we see that here, we deal with it by using values from | |
137 | * a current RTC timestamp for any missing (-1) values. The | |
138 | * RTC driver prevents "periodic alarm" modes. | |
139 | * | |
140 | * But this can be racey, because some fields of the RTC timestamp | |
141 | * may have wrapped in the interval since we read the RTC alarm, | |
142 | * which would lead to us inserting inconsistent values in place | |
143 | * of the -1 fields. | |
144 | * | |
145 | * Reading the alarm and timestamp in the reverse sequence | |
146 | * would have the same race condition, and not solve the issue. | |
147 | * | |
148 | * So, we must first read the RTC timestamp, | |
149 | * then read the RTC alarm value, | |
150 | * and then read a second RTC timestamp. | |
151 | * | |
152 | * If any fields of the second timestamp have changed | |
153 | * when compared with the first timestamp, then we know | |
154 | * our timestamp may be inconsistent with that used by | |
155 | * the low-level rtc_read_alarm_internal() function. | |
156 | * | |
157 | * So, when the two timestamps disagree, we just loop and do | |
158 | * the process again to get a fully consistent set of values. | |
159 | * | |
160 | * This could all instead be done in the lower level driver, | |
161 | * but since more than one lower level RTC implementation needs it, | |
162 | * then it's probably best best to do it here instead of there.. | |
163 | */ | |
164 | ||
165 | /* Get the "before" timestamp */ | |
166 | err = rtc_read_time(rtc, &before); | |
167 | if (err < 0) | |
168 | return err; | |
169 | do { | |
170 | if (!first_time) | |
171 | memcpy(&before, &now, sizeof(struct rtc_time)); | |
172 | first_time = 0; | |
173 | ||
174 | /* get the RTC alarm values, which may be incomplete */ | |
175 | err = rtc_read_alarm_internal(rtc, alarm); | |
176 | if (err) | |
177 | return err; | |
178 | ||
179 | /* full-function RTCs won't have such missing fields */ | |
180 | if (rtc_valid_tm(&alarm->time) == 0) | |
181 | return 0; | |
182 | ||
183 | /* get the "after" timestamp, to detect wrapped fields */ | |
184 | err = rtc_read_time(rtc, &now); | |
185 | if (err < 0) | |
186 | return err; | |
187 | ||
188 | /* note that tm_sec is a "don't care" value here: */ | |
189 | } while ( before.tm_min != now.tm_min | |
190 | || before.tm_hour != now.tm_hour | |
191 | || before.tm_mon != now.tm_mon | |
192 | || before.tm_year != now.tm_year); | |
193 | ||
194 | /* Fill in the missing alarm fields using the timestamp; we | |
195 | * know there's at least one since alarm->time is invalid. | |
196 | */ | |
197 | if (alarm->time.tm_sec == -1) | |
198 | alarm->time.tm_sec = now.tm_sec; | |
199 | if (alarm->time.tm_min == -1) | |
200 | alarm->time.tm_min = now.tm_min; | |
201 | if (alarm->time.tm_hour == -1) | |
202 | alarm->time.tm_hour = now.tm_hour; | |
203 | ||
204 | /* For simplicity, only support date rollover for now */ | |
e74a8f2e | 205 | if (alarm->time.tm_mday < 1 || alarm->time.tm_mday > 31) { |
f44f7f96 JS |
206 | alarm->time.tm_mday = now.tm_mday; |
207 | missing = day; | |
208 | } | |
e74a8f2e | 209 | if ((unsigned)alarm->time.tm_mon >= 12) { |
f44f7f96 JS |
210 | alarm->time.tm_mon = now.tm_mon; |
211 | if (missing == none) | |
212 | missing = month; | |
213 | } | |
214 | if (alarm->time.tm_year == -1) { | |
215 | alarm->time.tm_year = now.tm_year; | |
216 | if (missing == none) | |
217 | missing = year; | |
218 | } | |
219 | ||
220 | /* with luck, no rollover is needed */ | |
bc10aa93 XP |
221 | t_now = rtc_tm_to_time64(&now); |
222 | t_alm = rtc_tm_to_time64(&alarm->time); | |
f44f7f96 JS |
223 | if (t_now < t_alm) |
224 | goto done; | |
225 | ||
226 | switch (missing) { | |
227 | ||
228 | /* 24 hour rollover ... if it's now 10am Monday, an alarm that | |
229 | * that will trigger at 5am will do so at 5am Tuesday, which | |
230 | * could also be in the next month or year. This is a common | |
231 | * case, especially for PCs. | |
232 | */ | |
233 | case day: | |
234 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "day"); | |
235 | t_alm += 24 * 60 * 60; | |
bc10aa93 | 236 | rtc_time64_to_tm(t_alm, &alarm->time); |
f44f7f96 JS |
237 | break; |
238 | ||
239 | /* Month rollover ... if it's the 31th, an alarm on the 3rd will | |
240 | * be next month. An alarm matching on the 30th, 29th, or 28th | |
241 | * may end up in the month after that! Many newer PCs support | |
242 | * this type of alarm. | |
243 | */ | |
244 | case month: | |
245 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "month"); | |
246 | do { | |
247 | if (alarm->time.tm_mon < 11) | |
248 | alarm->time.tm_mon++; | |
249 | else { | |
250 | alarm->time.tm_mon = 0; | |
251 | alarm->time.tm_year++; | |
252 | } | |
253 | days = rtc_month_days(alarm->time.tm_mon, | |
254 | alarm->time.tm_year); | |
255 | } while (days < alarm->time.tm_mday); | |
256 | break; | |
257 | ||
258 | /* Year rollover ... easy except for leap years! */ | |
259 | case year: | |
260 | dev_dbg(&rtc->dev, "alarm rollover: %s\n", "year"); | |
261 | do { | |
262 | alarm->time.tm_year++; | |
ee1d9014 AN |
263 | } while (!is_leap_year(alarm->time.tm_year + 1900) |
264 | && rtc_valid_tm(&alarm->time) != 0); | |
f44f7f96 JS |
265 | break; |
266 | ||
267 | default: | |
268 | dev_warn(&rtc->dev, "alarm rollover not handled\n"); | |
269 | } | |
270 | ||
271 | done: | |
ee1d9014 AN |
272 | err = rtc_valid_tm(&alarm->time); |
273 | ||
274 | if (err) { | |
275 | dev_warn(&rtc->dev, "invalid alarm value: %d-%d-%d %d:%d:%d\n", | |
276 | alarm->time.tm_year + 1900, alarm->time.tm_mon + 1, | |
277 | alarm->time.tm_mday, alarm->time.tm_hour, alarm->time.tm_min, | |
278 | alarm->time.tm_sec); | |
279 | } | |
280 | ||
281 | return err; | |
f44f7f96 JS |
282 | } |
283 | ||
6610e089 | 284 | int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0c86edc0 AZ |
285 | { |
286 | int err; | |
0c86edc0 AZ |
287 | |
288 | err = mutex_lock_interruptible(&rtc->ops_lock); | |
289 | if (err) | |
b68bb263 | 290 | return err; |
d5553a55 JS |
291 | if (rtc->ops == NULL) |
292 | err = -ENODEV; | |
293 | else if (!rtc->ops->read_alarm) | |
294 | err = -EINVAL; | |
295 | else { | |
296 | memset(alarm, 0, sizeof(struct rtc_wkalrm)); | |
297 | alarm->enabled = rtc->aie_timer.enabled; | |
6610e089 | 298 | alarm->time = rtc_ktime_to_tm(rtc->aie_timer.node.expires); |
d5553a55 | 299 | } |
0c86edc0 | 300 | mutex_unlock(&rtc->ops_lock); |
6610e089 | 301 | |
d5553a55 | 302 | return err; |
0c86edc0 | 303 | } |
6610e089 | 304 | EXPORT_SYMBOL_GPL(rtc_read_alarm); |
0e36a9a4 | 305 | |
d576fe49 | 306 | static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0e36a9a4 | 307 | { |
6610e089 | 308 | struct rtc_time tm; |
bc10aa93 | 309 | time64_t now, scheduled; |
0e36a9a4 | 310 | int err; |
0e36a9a4 | 311 | |
6610e089 JS |
312 | err = rtc_valid_tm(&alarm->time); |
313 | if (err) | |
0e36a9a4 | 314 | return err; |
bc10aa93 | 315 | scheduled = rtc_tm_to_time64(&alarm->time); |
a01cc657 | 316 | |
6610e089 JS |
317 | /* Make sure we're not setting alarms in the past */ |
318 | err = __rtc_read_time(rtc, &tm); | |
ca6dc2da HG |
319 | if (err) |
320 | return err; | |
bc10aa93 | 321 | now = rtc_tm_to_time64(&tm); |
6610e089 JS |
322 | if (scheduled <= now) |
323 | return -ETIME; | |
324 | /* | |
325 | * XXX - We just checked to make sure the alarm time is not | |
326 | * in the past, but there is still a race window where if | |
327 | * the is alarm set for the next second and the second ticks | |
328 | * over right here, before we set the alarm. | |
a01cc657 | 329 | */ |
a01cc657 | 330 | |
157e8bf8 LT |
331 | if (!rtc->ops) |
332 | err = -ENODEV; | |
333 | else if (!rtc->ops->set_alarm) | |
334 | err = -EINVAL; | |
335 | else | |
336 | err = rtc->ops->set_alarm(rtc->dev.parent, alarm); | |
337 | ||
338 | return err; | |
0e36a9a4 | 339 | } |
0c86edc0 | 340 | |
ab6a2d70 | 341 | int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) |
0c86edc0 AZ |
342 | { |
343 | int err; | |
0c86edc0 | 344 | |
f8245c26 DB |
345 | err = rtc_valid_tm(&alarm->time); |
346 | if (err != 0) | |
347 | return err; | |
348 | ||
0c86edc0 AZ |
349 | err = mutex_lock_interruptible(&rtc->ops_lock); |
350 | if (err) | |
b68bb263 | 351 | return err; |
3ff2e13c | 352 | if (rtc->aie_timer.enabled) |
96c8f06a | 353 | rtc_timer_remove(rtc, &rtc->aie_timer); |
3ff2e13c | 354 | |
6610e089 JS |
355 | rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time); |
356 | rtc->aie_timer.period = ktime_set(0, 0); | |
3ff2e13c | 357 | if (alarm->enabled) |
aa0be0f4 | 358 | err = rtc_timer_enqueue(rtc, &rtc->aie_timer); |
3ff2e13c | 359 | |
0c86edc0 | 360 | mutex_unlock(&rtc->ops_lock); |
aa0be0f4 | 361 | return err; |
0c86edc0 AZ |
362 | } |
363 | EXPORT_SYMBOL_GPL(rtc_set_alarm); | |
364 | ||
f6d5b331 JS |
365 | /* Called once per device from rtc_device_register */ |
366 | int rtc_initialize_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) | |
367 | { | |
368 | int err; | |
bd729d72 | 369 | struct rtc_time now; |
f6d5b331 JS |
370 | |
371 | err = rtc_valid_tm(&alarm->time); | |
372 | if (err != 0) | |
373 | return err; | |
374 | ||
bd729d72 JS |
375 | err = rtc_read_time(rtc, &now); |
376 | if (err) | |
377 | return err; | |
378 | ||
f6d5b331 JS |
379 | err = mutex_lock_interruptible(&rtc->ops_lock); |
380 | if (err) | |
381 | return err; | |
382 | ||
383 | rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time); | |
384 | rtc->aie_timer.period = ktime_set(0, 0); | |
bd729d72 JS |
385 | |
386 | /* Alarm has to be enabled & in the futrure for us to enqueue it */ | |
387 | if (alarm->enabled && (rtc_tm_to_ktime(now).tv64 < | |
388 | rtc->aie_timer.node.expires.tv64)) { | |
389 | ||
f6d5b331 JS |
390 | rtc->aie_timer.enabled = 1; |
391 | timerqueue_add(&rtc->timerqueue, &rtc->aie_timer.node); | |
392 | } | |
393 | mutex_unlock(&rtc->ops_lock); | |
394 | return err; | |
395 | } | |
396 | EXPORT_SYMBOL_GPL(rtc_initialize_alarm); | |
397 | ||
398 | ||
399 | ||
099e6576 AZ |
400 | int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled) |
401 | { | |
402 | int err = mutex_lock_interruptible(&rtc->ops_lock); | |
403 | if (err) | |
404 | return err; | |
405 | ||
6610e089 | 406 | if (rtc->aie_timer.enabled != enabled) { |
aa0be0f4 JS |
407 | if (enabled) |
408 | err = rtc_timer_enqueue(rtc, &rtc->aie_timer); | |
409 | else | |
96c8f06a | 410 | rtc_timer_remove(rtc, &rtc->aie_timer); |
6610e089 JS |
411 | } |
412 | ||
aa0be0f4 | 413 | if (err) |
516373b8 UKK |
414 | /* nothing */; |
415 | else if (!rtc->ops) | |
099e6576 AZ |
416 | err = -ENODEV; |
417 | else if (!rtc->ops->alarm_irq_enable) | |
418 | err = -EINVAL; | |
419 | else | |
420 | err = rtc->ops->alarm_irq_enable(rtc->dev.parent, enabled); | |
421 | ||
422 | mutex_unlock(&rtc->ops_lock); | |
423 | return err; | |
424 | } | |
425 | EXPORT_SYMBOL_GPL(rtc_alarm_irq_enable); | |
426 | ||
427 | int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled) | |
428 | { | |
429 | int err = mutex_lock_interruptible(&rtc->ops_lock); | |
430 | if (err) | |
431 | return err; | |
432 | ||
456d66ec JS |
433 | #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL |
434 | if (enabled == 0 && rtc->uie_irq_active) { | |
435 | mutex_unlock(&rtc->ops_lock); | |
436 | return rtc_dev_update_irq_enable_emul(rtc, 0); | |
437 | } | |
438 | #endif | |
6610e089 JS |
439 | /* make sure we're changing state */ |
440 | if (rtc->uie_rtctimer.enabled == enabled) | |
441 | goto out; | |
442 | ||
4a649903 JS |
443 | if (rtc->uie_unsupported) { |
444 | err = -EINVAL; | |
445 | goto out; | |
446 | } | |
447 | ||
6610e089 JS |
448 | if (enabled) { |
449 | struct rtc_time tm; | |
450 | ktime_t now, onesec; | |
451 | ||
452 | __rtc_read_time(rtc, &tm); | |
453 | onesec = ktime_set(1, 0); | |
454 | now = rtc_tm_to_ktime(tm); | |
455 | rtc->uie_rtctimer.node.expires = ktime_add(now, onesec); | |
456 | rtc->uie_rtctimer.period = ktime_set(1, 0); | |
aa0be0f4 JS |
457 | err = rtc_timer_enqueue(rtc, &rtc->uie_rtctimer); |
458 | } else | |
96c8f06a | 459 | rtc_timer_remove(rtc, &rtc->uie_rtctimer); |
099e6576 | 460 | |
6610e089 | 461 | out: |
099e6576 | 462 | mutex_unlock(&rtc->ops_lock); |
456d66ec JS |
463 | #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL |
464 | /* | |
465 | * Enable emulation if the driver did not provide | |
466 | * the update_irq_enable function pointer or if returned | |
467 | * -EINVAL to signal that it has been configured without | |
468 | * interrupts or that are not available at the moment. | |
469 | */ | |
470 | if (err == -EINVAL) | |
471 | err = rtc_dev_update_irq_enable_emul(rtc, enabled); | |
472 | #endif | |
099e6576 | 473 | return err; |
6610e089 | 474 | |
099e6576 AZ |
475 | } |
476 | EXPORT_SYMBOL_GPL(rtc_update_irq_enable); | |
477 | ||
6610e089 | 478 | |
d728b1e6 | 479 | /** |
6610e089 JS |
480 | * rtc_handle_legacy_irq - AIE, UIE and PIE event hook |
481 | * @rtc: pointer to the rtc device | |
482 | * | |
483 | * This function is called when an AIE, UIE or PIE mode interrupt | |
25985edc | 484 | * has occurred (or been emulated). |
6610e089 JS |
485 | * |
486 | * Triggers the registered irq_task function callback. | |
d728b1e6 | 487 | */ |
456d66ec | 488 | void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode) |
0c86edc0 | 489 | { |
e6229bec AN |
490 | unsigned long flags; |
491 | ||
6610e089 | 492 | /* mark one irq of the appropriate mode */ |
e6229bec | 493 | spin_lock_irqsave(&rtc->irq_lock, flags); |
6610e089 | 494 | rtc->irq_data = (rtc->irq_data + (num << 8)) | (RTC_IRQF|mode); |
e6229bec | 495 | spin_unlock_irqrestore(&rtc->irq_lock, flags); |
0c86edc0 | 496 | |
6610e089 | 497 | /* call the task func */ |
e6229bec | 498 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
499 | if (rtc->irq_task) |
500 | rtc->irq_task->func(rtc->irq_task->private_data); | |
e6229bec | 501 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
502 | |
503 | wake_up_interruptible(&rtc->irq_queue); | |
504 | kill_fasync(&rtc->async_queue, SIGIO, POLL_IN); | |
505 | } | |
6610e089 JS |
506 | |
507 | ||
508 | /** | |
509 | * rtc_aie_update_irq - AIE mode rtctimer hook | |
510 | * @private: pointer to the rtc_device | |
511 | * | |
512 | * This functions is called when the aie_timer expires. | |
513 | */ | |
514 | void rtc_aie_update_irq(void *private) | |
515 | { | |
516 | struct rtc_device *rtc = (struct rtc_device *)private; | |
517 | rtc_handle_legacy_irq(rtc, 1, RTC_AF); | |
518 | } | |
519 | ||
520 | ||
521 | /** | |
522 | * rtc_uie_update_irq - UIE mode rtctimer hook | |
523 | * @private: pointer to the rtc_device | |
524 | * | |
525 | * This functions is called when the uie_timer expires. | |
526 | */ | |
527 | void rtc_uie_update_irq(void *private) | |
528 | { | |
529 | struct rtc_device *rtc = (struct rtc_device *)private; | |
530 | rtc_handle_legacy_irq(rtc, 1, RTC_UF); | |
531 | } | |
532 | ||
533 | ||
534 | /** | |
535 | * rtc_pie_update_irq - PIE mode hrtimer hook | |
536 | * @timer: pointer to the pie mode hrtimer | |
537 | * | |
538 | * This function is used to emulate PIE mode interrupts | |
539 | * using an hrtimer. This function is called when the periodic | |
540 | * hrtimer expires. | |
541 | */ | |
542 | enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer) | |
543 | { | |
544 | struct rtc_device *rtc; | |
545 | ktime_t period; | |
546 | int count; | |
547 | rtc = container_of(timer, struct rtc_device, pie_timer); | |
548 | ||
549 | period = ktime_set(0, NSEC_PER_SEC/rtc->irq_freq); | |
550 | count = hrtimer_forward_now(timer, period); | |
551 | ||
552 | rtc_handle_legacy_irq(rtc, count, RTC_PF); | |
553 | ||
554 | return HRTIMER_RESTART; | |
555 | } | |
556 | ||
557 | /** | |
558 | * rtc_update_irq - Triggered when a RTC interrupt occurs. | |
559 | * @rtc: the rtc device | |
560 | * @num: how many irqs are being reported (usually one) | |
561 | * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF | |
562 | * Context: any | |
563 | */ | |
564 | void rtc_update_irq(struct rtc_device *rtc, | |
565 | unsigned long num, unsigned long events) | |
566 | { | |
131c9cc8 AZ |
567 | if (unlikely(IS_ERR_OR_NULL(rtc))) |
568 | return; | |
569 | ||
7523ceed | 570 | pm_stay_awake(rtc->dev.parent); |
6610e089 JS |
571 | schedule_work(&rtc->irqwork); |
572 | } | |
0c86edc0 AZ |
573 | EXPORT_SYMBOL_GPL(rtc_update_irq); |
574 | ||
9f3b795a | 575 | static int __rtc_match(struct device *dev, const void *data) |
71da8905 | 576 | { |
9f3b795a | 577 | const char *name = data; |
71da8905 | 578 | |
d4afc76c | 579 | if (strcmp(dev_name(dev), name) == 0) |
71da8905 DY |
580 | return 1; |
581 | return 0; | |
582 | } | |
583 | ||
9f3b795a | 584 | struct rtc_device *rtc_class_open(const char *name) |
0c86edc0 | 585 | { |
cd966209 | 586 | struct device *dev; |
ab6a2d70 | 587 | struct rtc_device *rtc = NULL; |
0c86edc0 | 588 | |
695794ae | 589 | dev = class_find_device(rtc_class, NULL, name, __rtc_match); |
71da8905 DY |
590 | if (dev) |
591 | rtc = to_rtc_device(dev); | |
0c86edc0 | 592 | |
ab6a2d70 DB |
593 | if (rtc) { |
594 | if (!try_module_get(rtc->owner)) { | |
cd966209 | 595 | put_device(dev); |
ab6a2d70 DB |
596 | rtc = NULL; |
597 | } | |
0c86edc0 | 598 | } |
0c86edc0 | 599 | |
ab6a2d70 | 600 | return rtc; |
0c86edc0 AZ |
601 | } |
602 | EXPORT_SYMBOL_GPL(rtc_class_open); | |
603 | ||
ab6a2d70 | 604 | void rtc_class_close(struct rtc_device *rtc) |
0c86edc0 | 605 | { |
ab6a2d70 | 606 | module_put(rtc->owner); |
cd966209 | 607 | put_device(&rtc->dev); |
0c86edc0 AZ |
608 | } |
609 | EXPORT_SYMBOL_GPL(rtc_class_close); | |
610 | ||
ab6a2d70 | 611 | int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task) |
0c86edc0 AZ |
612 | { |
613 | int retval = -EBUSY; | |
0c86edc0 AZ |
614 | |
615 | if (task == NULL || task->func == NULL) | |
616 | return -EINVAL; | |
617 | ||
d691eb90 | 618 | /* Cannot register while the char dev is in use */ |
372a302e | 619 | if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags)) |
d691eb90 AZ |
620 | return -EBUSY; |
621 | ||
d728b1e6 | 622 | spin_lock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
623 | if (rtc->irq_task == NULL) { |
624 | rtc->irq_task = task; | |
625 | retval = 0; | |
626 | } | |
d728b1e6 | 627 | spin_unlock_irq(&rtc->irq_task_lock); |
0c86edc0 | 628 | |
372a302e | 629 | clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags); |
d691eb90 | 630 | |
0c86edc0 AZ |
631 | return retval; |
632 | } | |
633 | EXPORT_SYMBOL_GPL(rtc_irq_register); | |
634 | ||
ab6a2d70 | 635 | void rtc_irq_unregister(struct rtc_device *rtc, struct rtc_task *task) |
0c86edc0 | 636 | { |
d728b1e6 | 637 | spin_lock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
638 | if (rtc->irq_task == task) |
639 | rtc->irq_task = NULL; | |
d728b1e6 | 640 | spin_unlock_irq(&rtc->irq_task_lock); |
0c86edc0 AZ |
641 | } |
642 | EXPORT_SYMBOL_GPL(rtc_irq_unregister); | |
643 | ||
3c8bb90e TG |
644 | static int rtc_update_hrtimer(struct rtc_device *rtc, int enabled) |
645 | { | |
646 | /* | |
647 | * We always cancel the timer here first, because otherwise | |
648 | * we could run into BUG_ON(timer->state != HRTIMER_STATE_CALLBACK); | |
649 | * when we manage to start the timer before the callback | |
650 | * returns HRTIMER_RESTART. | |
651 | * | |
652 | * We cannot use hrtimer_cancel() here as a running callback | |
653 | * could be blocked on rtc->irq_task_lock and hrtimer_cancel() | |
654 | * would spin forever. | |
655 | */ | |
656 | if (hrtimer_try_to_cancel(&rtc->pie_timer) < 0) | |
657 | return -1; | |
658 | ||
659 | if (enabled) { | |
660 | ktime_t period = ktime_set(0, NSEC_PER_SEC / rtc->irq_freq); | |
661 | ||
662 | hrtimer_start(&rtc->pie_timer, period, HRTIMER_MODE_REL); | |
663 | } | |
664 | return 0; | |
665 | } | |
666 | ||
97144c67 DB |
667 | /** |
668 | * rtc_irq_set_state - enable/disable 2^N Hz periodic IRQs | |
669 | * @rtc: the rtc device | |
670 | * @task: currently registered with rtc_irq_register() | |
671 | * @enabled: true to enable periodic IRQs | |
672 | * Context: any | |
673 | * | |
674 | * Note that rtc_irq_set_freq() should previously have been used to | |
675 | * specify the desired frequency of periodic IRQ task->func() callbacks. | |
676 | */ | |
ab6a2d70 | 677 | int rtc_irq_set_state(struct rtc_device *rtc, struct rtc_task *task, int enabled) |
0c86edc0 AZ |
678 | { |
679 | int err = 0; | |
680 | unsigned long flags; | |
0c86edc0 | 681 | |
3c8bb90e | 682 | retry: |
0c86edc0 | 683 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
d691eb90 AZ |
684 | if (rtc->irq_task != NULL && task == NULL) |
685 | err = -EBUSY; | |
0734e27f | 686 | else if (rtc->irq_task != task) |
d691eb90 | 687 | err = -EACCES; |
0734e27f | 688 | else { |
3c8bb90e TG |
689 | if (rtc_update_hrtimer(rtc, enabled) < 0) { |
690 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); | |
691 | cpu_relax(); | |
692 | goto retry; | |
693 | } | |
694 | rtc->pie_enabled = enabled; | |
6610e089 | 695 | } |
6610e089 | 696 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
697 | return err; |
698 | } | |
699 | EXPORT_SYMBOL_GPL(rtc_irq_set_state); | |
700 | ||
97144c67 DB |
701 | /** |
702 | * rtc_irq_set_freq - set 2^N Hz periodic IRQ frequency for IRQ | |
703 | * @rtc: the rtc device | |
704 | * @task: currently registered with rtc_irq_register() | |
705 | * @freq: positive frequency with which task->func() will be called | |
706 | * Context: any | |
707 | * | |
708 | * Note that rtc_irq_set_state() is used to enable or disable the | |
709 | * periodic IRQs. | |
710 | */ | |
ab6a2d70 | 711 | int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq) |
0c86edc0 | 712 | { |
56f10c63 | 713 | int err = 0; |
0c86edc0 | 714 | unsigned long flags; |
0c86edc0 | 715 | |
6e7a333e | 716 | if (freq <= 0 || freq > RTC_MAX_FREQ) |
83a06bf5 | 717 | return -EINVAL; |
3c8bb90e | 718 | retry: |
0c86edc0 | 719 | spin_lock_irqsave(&rtc->irq_task_lock, flags); |
d691eb90 AZ |
720 | if (rtc->irq_task != NULL && task == NULL) |
721 | err = -EBUSY; | |
0734e27f | 722 | else if (rtc->irq_task != task) |
d691eb90 | 723 | err = -EACCES; |
0734e27f | 724 | else { |
6610e089 | 725 | rtc->irq_freq = freq; |
3c8bb90e TG |
726 | if (rtc->pie_enabled && rtc_update_hrtimer(rtc, 1) < 0) { |
727 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); | |
728 | cpu_relax(); | |
729 | goto retry; | |
6610e089 | 730 | } |
0c86edc0 | 731 | } |
6610e089 | 732 | spin_unlock_irqrestore(&rtc->irq_task_lock, flags); |
0c86edc0 AZ |
733 | return err; |
734 | } | |
2601a464 | 735 | EXPORT_SYMBOL_GPL(rtc_irq_set_freq); |
6610e089 JS |
736 | |
737 | /** | |
96c8f06a | 738 | * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue |
6610e089 JS |
739 | * @rtc rtc device |
740 | * @timer timer being added. | |
741 | * | |
742 | * Enqueues a timer onto the rtc devices timerqueue and sets | |
743 | * the next alarm event appropriately. | |
744 | * | |
aa0be0f4 JS |
745 | * Sets the enabled bit on the added timer. |
746 | * | |
6610e089 JS |
747 | * Must hold ops_lock for proper serialization of timerqueue |
748 | */ | |
aa0be0f4 | 749 | static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) |
6610e089 | 750 | { |
aa0be0f4 | 751 | timer->enabled = 1; |
6610e089 JS |
752 | timerqueue_add(&rtc->timerqueue, &timer->node); |
753 | if (&timer->node == timerqueue_getnext(&rtc->timerqueue)) { | |
754 | struct rtc_wkalrm alarm; | |
755 | int err; | |
756 | alarm.time = rtc_ktime_to_tm(timer->node.expires); | |
757 | alarm.enabled = 1; | |
758 | err = __rtc_set_alarm(rtc, &alarm); | |
14d0e347 ZM |
759 | if (err == -ETIME) { |
760 | pm_stay_awake(rtc->dev.parent); | |
6610e089 | 761 | schedule_work(&rtc->irqwork); |
14d0e347 | 762 | } else if (err) { |
aa0be0f4 JS |
763 | timerqueue_del(&rtc->timerqueue, &timer->node); |
764 | timer->enabled = 0; | |
765 | return err; | |
766 | } | |
6610e089 | 767 | } |
aa0be0f4 | 768 | return 0; |
6610e089 JS |
769 | } |
770 | ||
41c7f742 RV |
771 | static void rtc_alarm_disable(struct rtc_device *rtc) |
772 | { | |
773 | if (!rtc->ops || !rtc->ops->alarm_irq_enable) | |
774 | return; | |
775 | ||
776 | rtc->ops->alarm_irq_enable(rtc->dev.parent, false); | |
777 | } | |
778 | ||
6610e089 | 779 | /** |
96c8f06a | 780 | * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue |
6610e089 JS |
781 | * @rtc rtc device |
782 | * @timer timer being removed. | |
783 | * | |
784 | * Removes a timer onto the rtc devices timerqueue and sets | |
785 | * the next alarm event appropriately. | |
786 | * | |
aa0be0f4 JS |
787 | * Clears the enabled bit on the removed timer. |
788 | * | |
6610e089 JS |
789 | * Must hold ops_lock for proper serialization of timerqueue |
790 | */ | |
aa0be0f4 | 791 | static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer) |
6610e089 JS |
792 | { |
793 | struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue); | |
794 | timerqueue_del(&rtc->timerqueue, &timer->node); | |
aa0be0f4 | 795 | timer->enabled = 0; |
6610e089 JS |
796 | if (next == &timer->node) { |
797 | struct rtc_wkalrm alarm; | |
798 | int err; | |
799 | next = timerqueue_getnext(&rtc->timerqueue); | |
41c7f742 RV |
800 | if (!next) { |
801 | rtc_alarm_disable(rtc); | |
6610e089 | 802 | return; |
41c7f742 | 803 | } |
6610e089 JS |
804 | alarm.time = rtc_ktime_to_tm(next->expires); |
805 | alarm.enabled = 1; | |
806 | err = __rtc_set_alarm(rtc, &alarm); | |
14d0e347 ZM |
807 | if (err == -ETIME) { |
808 | pm_stay_awake(rtc->dev.parent); | |
6610e089 | 809 | schedule_work(&rtc->irqwork); |
14d0e347 | 810 | } |
6610e089 JS |
811 | } |
812 | } | |
813 | ||
814 | /** | |
96c8f06a | 815 | * rtc_timer_do_work - Expires rtc timers |
6610e089 JS |
816 | * @rtc rtc device |
817 | * @timer timer being removed. | |
818 | * | |
819 | * Expires rtc timers. Reprograms next alarm event if needed. | |
820 | * Called via worktask. | |
821 | * | |
822 | * Serializes access to timerqueue via ops_lock mutex | |
823 | */ | |
96c8f06a | 824 | void rtc_timer_do_work(struct work_struct *work) |
6610e089 JS |
825 | { |
826 | struct rtc_timer *timer; | |
827 | struct timerqueue_node *next; | |
828 | ktime_t now; | |
829 | struct rtc_time tm; | |
830 | ||
831 | struct rtc_device *rtc = | |
832 | container_of(work, struct rtc_device, irqwork); | |
833 | ||
834 | mutex_lock(&rtc->ops_lock); | |
835 | again: | |
836 | __rtc_read_time(rtc, &tm); | |
837 | now = rtc_tm_to_ktime(tm); | |
838 | while ((next = timerqueue_getnext(&rtc->timerqueue))) { | |
839 | if (next->expires.tv64 > now.tv64) | |
840 | break; | |
841 | ||
842 | /* expire timer */ | |
843 | timer = container_of(next, struct rtc_timer, node); | |
844 | timerqueue_del(&rtc->timerqueue, &timer->node); | |
845 | timer->enabled = 0; | |
846 | if (timer->task.func) | |
847 | timer->task.func(timer->task.private_data); | |
848 | ||
849 | /* Re-add/fwd periodic timers */ | |
850 | if (ktime_to_ns(timer->period)) { | |
851 | timer->node.expires = ktime_add(timer->node.expires, | |
852 | timer->period); | |
853 | timer->enabled = 1; | |
854 | timerqueue_add(&rtc->timerqueue, &timer->node); | |
855 | } | |
856 | } | |
857 | ||
858 | /* Set next alarm */ | |
859 | if (next) { | |
860 | struct rtc_wkalrm alarm; | |
861 | int err; | |
6528b889 XP |
862 | int retry = 3; |
863 | ||
6610e089 JS |
864 | alarm.time = rtc_ktime_to_tm(next->expires); |
865 | alarm.enabled = 1; | |
6528b889 | 866 | reprogram: |
6610e089 JS |
867 | err = __rtc_set_alarm(rtc, &alarm); |
868 | if (err == -ETIME) | |
869 | goto again; | |
6528b889 XP |
870 | else if (err) { |
871 | if (retry-- > 0) | |
872 | goto reprogram; | |
873 | ||
874 | timer = container_of(next, struct rtc_timer, node); | |
875 | timerqueue_del(&rtc->timerqueue, &timer->node); | |
876 | timer->enabled = 0; | |
877 | dev_err(&rtc->dev, "__rtc_set_alarm: err=%d\n", err); | |
878 | goto again; | |
879 | } | |
41c7f742 RV |
880 | } else |
881 | rtc_alarm_disable(rtc); | |
6610e089 | 882 | |
14d0e347 | 883 | pm_relax(rtc->dev.parent); |
6610e089 JS |
884 | mutex_unlock(&rtc->ops_lock); |
885 | } | |
886 | ||
887 | ||
96c8f06a | 888 | /* rtc_timer_init - Initializes an rtc_timer |
6610e089 JS |
889 | * @timer: timer to be intiialized |
890 | * @f: function pointer to be called when timer fires | |
891 | * @data: private data passed to function pointer | |
892 | * | |
893 | * Kernel interface to initializing an rtc_timer. | |
894 | */ | |
3ff2e13c | 895 | void rtc_timer_init(struct rtc_timer *timer, void (*f)(void *p), void *data) |
6610e089 JS |
896 | { |
897 | timerqueue_init(&timer->node); | |
898 | timer->enabled = 0; | |
899 | timer->task.func = f; | |
900 | timer->task.private_data = data; | |
901 | } | |
902 | ||
96c8f06a | 903 | /* rtc_timer_start - Sets an rtc_timer to fire in the future |
6610e089 JS |
904 | * @ rtc: rtc device to be used |
905 | * @ timer: timer being set | |
906 | * @ expires: time at which to expire the timer | |
907 | * @ period: period that the timer will recur | |
908 | * | |
909 | * Kernel interface to set an rtc_timer | |
910 | */ | |
3ff2e13c | 911 | int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer *timer, |
6610e089 JS |
912 | ktime_t expires, ktime_t period) |
913 | { | |
914 | int ret = 0; | |
915 | mutex_lock(&rtc->ops_lock); | |
916 | if (timer->enabled) | |
96c8f06a | 917 | rtc_timer_remove(rtc, timer); |
6610e089 JS |
918 | |
919 | timer->node.expires = expires; | |
920 | timer->period = period; | |
921 | ||
aa0be0f4 | 922 | ret = rtc_timer_enqueue(rtc, timer); |
6610e089 JS |
923 | |
924 | mutex_unlock(&rtc->ops_lock); | |
925 | return ret; | |
926 | } | |
927 | ||
96c8f06a | 928 | /* rtc_timer_cancel - Stops an rtc_timer |
6610e089 JS |
929 | * @ rtc: rtc device to be used |
930 | * @ timer: timer being set | |
931 | * | |
932 | * Kernel interface to cancel an rtc_timer | |
933 | */ | |
73744a64 | 934 | void rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer *timer) |
6610e089 | 935 | { |
6610e089 JS |
936 | mutex_lock(&rtc->ops_lock); |
937 | if (timer->enabled) | |
96c8f06a | 938 | rtc_timer_remove(rtc, timer); |
6610e089 | 939 | mutex_unlock(&rtc->ops_lock); |
6610e089 JS |
940 | } |
941 | ||
942 |