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Commit | Line | Data |
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ff3ead96 JS |
1 | /* |
2 | * Alarmtimer interface | |
3 | * | |
4 | * This interface provides a timer which is similarto hrtimers, | |
5 | * but triggers a RTC alarm if the box is suspend. | |
6 | * | |
7 | * This interface is influenced by the Android RTC Alarm timer | |
8 | * interface. | |
9 | * | |
10 | * Copyright (C) 2010 IBM Corperation | |
11 | * | |
12 | * Author: John Stultz <john.stultz@linaro.org> | |
13 | * | |
14 | * This program is free software; you can redistribute it and/or modify | |
15 | * it under the terms of the GNU General Public License version 2 as | |
16 | * published by the Free Software Foundation. | |
17 | */ | |
18 | #include <linux/time.h> | |
19 | #include <linux/hrtimer.h> | |
20 | #include <linux/timerqueue.h> | |
21 | #include <linux/rtc.h> | |
174cd4b1 | 22 | #include <linux/sched/signal.h> |
b17b0153 | 23 | #include <linux/sched/debug.h> |
ff3ead96 JS |
24 | #include <linux/alarmtimer.h> |
25 | #include <linux/mutex.h> | |
26 | #include <linux/platform_device.h> | |
27 | #include <linux/posix-timers.h> | |
28 | #include <linux/workqueue.h> | |
29 | #include <linux/freezer.h> | |
30 | ||
4a057549 BW |
31 | #define CREATE_TRACE_POINTS |
32 | #include <trace/events/alarmtimer.h> | |
33 | ||
180bf812 JS |
34 | /** |
35 | * struct alarm_base - Alarm timer bases | |
36 | * @lock: Lock for syncrhonized access to the base | |
37 | * @timerqueue: Timerqueue head managing the list of events | |
180bf812 JS |
38 | * @gettime: Function to read the time correlating to the base |
39 | * @base_clockid: clockid for the base | |
180bf812 | 40 | */ |
ff3ead96 JS |
41 | static struct alarm_base { |
42 | spinlock_t lock; | |
43 | struct timerqueue_head timerqueue; | |
ff3ead96 JS |
44 | ktime_t (*gettime)(void); |
45 | clockid_t base_clockid; | |
ff3ead96 JS |
46 | } alarm_bases[ALARM_NUMTYPE]; |
47 | ||
4a057549 BW |
48 | /* freezer information to handle clock_nanosleep triggered wakeups */ |
49 | static enum alarmtimer_type freezer_alarmtype; | |
50 | static ktime_t freezer_expires; | |
c008ba58 JS |
51 | static ktime_t freezer_delta; |
52 | static DEFINE_SPINLOCK(freezer_delta_lock); | |
53 | ||
59a93c27 TP |
54 | static struct wakeup_source *ws; |
55 | ||
472647dc | 56 | #ifdef CONFIG_RTC_CLASS |
180bf812 | 57 | /* rtc timer and device for setting alarm wakeups at suspend */ |
c5e14e76 | 58 | static struct rtc_timer rtctimer; |
ff3ead96 | 59 | static struct rtc_device *rtcdev; |
c008ba58 | 60 | static DEFINE_SPINLOCK(rtcdev_lock); |
ff3ead96 | 61 | |
c008ba58 JS |
62 | /** |
63 | * alarmtimer_get_rtcdev - Return selected rtcdevice | |
64 | * | |
65 | * This function returns the rtc device to use for wakealarms. | |
66 | * If one has not already been chosen, it checks to see if a | |
67 | * functional rtc device is available. | |
68 | */ | |
57c498fa | 69 | struct rtc_device *alarmtimer_get_rtcdev(void) |
c008ba58 | 70 | { |
c008ba58 JS |
71 | unsigned long flags; |
72 | struct rtc_device *ret; | |
73 | ||
74 | spin_lock_irqsave(&rtcdev_lock, flags); | |
c008ba58 JS |
75 | ret = rtcdev; |
76 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
77 | ||
78 | return ret; | |
79 | } | |
71d5d2b7 | 80 | EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); |
8bc0dafb JS |
81 | |
82 | static int alarmtimer_rtc_add_device(struct device *dev, | |
83 | struct class_interface *class_intf) | |
84 | { | |
85 | unsigned long flags; | |
86 | struct rtc_device *rtc = to_rtc_device(dev); | |
87 | ||
88 | if (rtcdev) | |
89 | return -EBUSY; | |
90 | ||
91 | if (!rtc->ops->set_alarm) | |
92 | return -1; | |
93 | if (!device_may_wakeup(rtc->dev.parent)) | |
94 | return -1; | |
95 | ||
96 | spin_lock_irqsave(&rtcdev_lock, flags); | |
97 | if (!rtcdev) { | |
98 | rtcdev = rtc; | |
99 | /* hold a reference so it doesn't go away */ | |
100 | get_device(dev); | |
101 | } | |
102 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
103 | return 0; | |
104 | } | |
105 | ||
c5e14e76 TG |
106 | static inline void alarmtimer_rtc_timer_init(void) |
107 | { | |
108 | rtc_timer_init(&rtctimer, NULL, NULL); | |
109 | } | |
110 | ||
8bc0dafb JS |
111 | static struct class_interface alarmtimer_rtc_interface = { |
112 | .add_dev = &alarmtimer_rtc_add_device, | |
113 | }; | |
114 | ||
4523f6ad | 115 | static int alarmtimer_rtc_interface_setup(void) |
8bc0dafb JS |
116 | { |
117 | alarmtimer_rtc_interface.class = rtc_class; | |
4523f6ad TG |
118 | return class_interface_register(&alarmtimer_rtc_interface); |
119 | } | |
120 | static void alarmtimer_rtc_interface_remove(void) | |
121 | { | |
122 | class_interface_unregister(&alarmtimer_rtc_interface); | |
8bc0dafb | 123 | } |
1c6b39ad | 124 | #else |
57c498fa | 125 | struct rtc_device *alarmtimer_get_rtcdev(void) |
4523f6ad TG |
126 | { |
127 | return NULL; | |
128 | } | |
129 | #define rtcdev (NULL) | |
130 | static inline int alarmtimer_rtc_interface_setup(void) { return 0; } | |
131 | static inline void alarmtimer_rtc_interface_remove(void) { } | |
c5e14e76 | 132 | static inline void alarmtimer_rtc_timer_init(void) { } |
c008ba58 | 133 | #endif |
ff3ead96 | 134 | |
180bf812 | 135 | /** |
ff3ead96 JS |
136 | * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue |
137 | * @base: pointer to the base where the timer is being run | |
138 | * @alarm: pointer to alarm being enqueued. | |
139 | * | |
dae373be | 140 | * Adds alarm to a alarm_base timerqueue |
ff3ead96 JS |
141 | * |
142 | * Must hold base->lock when calling. | |
143 | */ | |
144 | static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) | |
145 | { | |
dae373be JS |
146 | if (alarm->state & ALARMTIMER_STATE_ENQUEUED) |
147 | timerqueue_del(&base->timerqueue, &alarm->node); | |
148 | ||
ff3ead96 | 149 | timerqueue_add(&base->timerqueue, &alarm->node); |
a28cde81 | 150 | alarm->state |= ALARMTIMER_STATE_ENQUEUED; |
ff3ead96 JS |
151 | } |
152 | ||
180bf812 | 153 | /** |
a65bcc12 | 154 | * alarmtimer_dequeue - Removes an alarm timer from an alarm_base timerqueue |
ff3ead96 JS |
155 | * @base: pointer to the base where the timer is running |
156 | * @alarm: pointer to alarm being removed | |
157 | * | |
dae373be | 158 | * Removes alarm to a alarm_base timerqueue |
ff3ead96 JS |
159 | * |
160 | * Must hold base->lock when calling. | |
161 | */ | |
a65bcc12 | 162 | static void alarmtimer_dequeue(struct alarm_base *base, struct alarm *alarm) |
ff3ead96 | 163 | { |
a28cde81 JS |
164 | if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) |
165 | return; | |
166 | ||
ff3ead96 | 167 | timerqueue_del(&base->timerqueue, &alarm->node); |
a28cde81 | 168 | alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; |
ff3ead96 JS |
169 | } |
170 | ||
7068b7a1 | 171 | |
180bf812 | 172 | /** |
7068b7a1 JS |
173 | * alarmtimer_fired - Handles alarm hrtimer being fired. |
174 | * @timer: pointer to hrtimer being run | |
ff3ead96 | 175 | * |
180bf812 JS |
176 | * When a alarm timer fires, this runs through the timerqueue to |
177 | * see which alarms expired, and runs those. If there are more alarm | |
178 | * timers queued for the future, we set the hrtimer to fire when | |
179 | * when the next future alarm timer expires. | |
ff3ead96 | 180 | */ |
7068b7a1 | 181 | static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) |
ff3ead96 | 182 | { |
dae373be JS |
183 | struct alarm *alarm = container_of(timer, struct alarm, timer); |
184 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
ff3ead96 | 185 | unsigned long flags; |
7068b7a1 | 186 | int ret = HRTIMER_NORESTART; |
54da23b7 | 187 | int restart = ALARMTIMER_NORESTART; |
ff3ead96 JS |
188 | |
189 | spin_lock_irqsave(&base->lock, flags); | |
a65bcc12 | 190 | alarmtimer_dequeue(base, alarm); |
dae373be | 191 | spin_unlock_irqrestore(&base->lock, flags); |
54da23b7 | 192 | |
dae373be JS |
193 | if (alarm->function) |
194 | restart = alarm->function(alarm, base->gettime()); | |
ff3ead96 | 195 | |
dae373be JS |
196 | spin_lock_irqsave(&base->lock, flags); |
197 | if (restart != ALARMTIMER_NORESTART) { | |
198 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); | |
199 | alarmtimer_enqueue(base, alarm); | |
7068b7a1 | 200 | ret = HRTIMER_RESTART; |
ff3ead96 JS |
201 | } |
202 | spin_unlock_irqrestore(&base->lock, flags); | |
ff3ead96 | 203 | |
4a057549 | 204 | trace_alarmtimer_fired(alarm, base->gettime()); |
7068b7a1 | 205 | return ret; |
ff3ead96 | 206 | |
ff3ead96 JS |
207 | } |
208 | ||
6cffe00f TP |
209 | ktime_t alarm_expires_remaining(const struct alarm *alarm) |
210 | { | |
211 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
212 | return ktime_sub(alarm->node.expires, base->gettime()); | |
213 | } | |
11682a41 | 214 | EXPORT_SYMBOL_GPL(alarm_expires_remaining); |
6cffe00f | 215 | |
472647dc | 216 | #ifdef CONFIG_RTC_CLASS |
180bf812 | 217 | /** |
ff3ead96 JS |
218 | * alarmtimer_suspend - Suspend time callback |
219 | * @dev: unused | |
220 | * @state: unused | |
221 | * | |
222 | * When we are going into suspend, we look through the bases | |
223 | * to see which is the soonest timer to expire. We then | |
224 | * set an rtc timer to fire that far into the future, which | |
225 | * will wake us from suspend. | |
226 | */ | |
227 | static int alarmtimer_suspend(struct device *dev) | |
228 | { | |
4a057549 BW |
229 | ktime_t min, now, expires; |
230 | int i, ret, type; | |
c008ba58 | 231 | struct rtc_device *rtc; |
4a057549 BW |
232 | unsigned long flags; |
233 | struct rtc_time tm; | |
ff3ead96 JS |
234 | |
235 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
236 | min = freezer_delta; | |
4a057549 BW |
237 | expires = freezer_expires; |
238 | type = freezer_alarmtype; | |
8b0e1953 | 239 | freezer_delta = 0; |
ff3ead96 JS |
240 | spin_unlock_irqrestore(&freezer_delta_lock, flags); |
241 | ||
8bc0dafb | 242 | rtc = alarmtimer_get_rtcdev(); |
ff3ead96 | 243 | /* If we have no rtcdev, just return */ |
c008ba58 | 244 | if (!rtc) |
ff3ead96 JS |
245 | return 0; |
246 | ||
247 | /* Find the soonest timer to expire*/ | |
248 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
249 | struct alarm_base *base = &alarm_bases[i]; | |
250 | struct timerqueue_node *next; | |
251 | ktime_t delta; | |
252 | ||
253 | spin_lock_irqsave(&base->lock, flags); | |
254 | next = timerqueue_getnext(&base->timerqueue); | |
255 | spin_unlock_irqrestore(&base->lock, flags); | |
256 | if (!next) | |
257 | continue; | |
258 | delta = ktime_sub(next->expires, base->gettime()); | |
2456e855 | 259 | if (!min || (delta < min)) { |
4a057549 | 260 | expires = next->expires; |
ff3ead96 | 261 | min = delta; |
4a057549 BW |
262 | type = i; |
263 | } | |
ff3ead96 | 264 | } |
2456e855 | 265 | if (min == 0) |
ff3ead96 JS |
266 | return 0; |
267 | ||
59a93c27 TP |
268 | if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { |
269 | __pm_wakeup_event(ws, 2 * MSEC_PER_SEC); | |
270 | return -EBUSY; | |
271 | } | |
ff3ead96 | 272 | |
4a057549 BW |
273 | trace_alarmtimer_suspend(expires, type); |
274 | ||
ff3ead96 | 275 | /* Setup an rtc timer to fire that far in the future */ |
c008ba58 JS |
276 | rtc_timer_cancel(rtc, &rtctimer); |
277 | rtc_read_time(rtc, &tm); | |
ff3ead96 JS |
278 | now = rtc_tm_to_ktime(tm); |
279 | now = ktime_add(now, min); | |
280 | ||
59a93c27 | 281 | /* Set alarm, if in the past reject suspend briefly to handle */ |
8b0e1953 | 282 | ret = rtc_timer_start(rtc, &rtctimer, now, 0); |
59a93c27 TP |
283 | if (ret < 0) |
284 | __pm_wakeup_event(ws, MSEC_PER_SEC); | |
285 | return ret; | |
ff3ead96 | 286 | } |
a0e3213f | 287 | |
288 | static int alarmtimer_resume(struct device *dev) | |
289 | { | |
290 | struct rtc_device *rtc; | |
291 | ||
292 | rtc = alarmtimer_get_rtcdev(); | |
293 | if (rtc) | |
294 | rtc_timer_cancel(rtc, &rtctimer); | |
295 | return 0; | |
296 | } | |
297 | ||
472647dc JS |
298 | #else |
299 | static int alarmtimer_suspend(struct device *dev) | |
300 | { | |
301 | return 0; | |
302 | } | |
a0e3213f | 303 | |
304 | static int alarmtimer_resume(struct device *dev) | |
305 | { | |
306 | return 0; | |
307 | } | |
472647dc | 308 | #endif |
ff3ead96 | 309 | |
9a7adcf5 JS |
310 | static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) |
311 | { | |
4a057549 | 312 | struct alarm_base *base; |
9a7adcf5 | 313 | unsigned long flags; |
4a057549 BW |
314 | ktime_t delta; |
315 | ||
316 | switch(type) { | |
317 | case ALARM_REALTIME: | |
318 | base = &alarm_bases[ALARM_REALTIME]; | |
319 | type = ALARM_REALTIME_FREEZER; | |
320 | break; | |
321 | case ALARM_BOOTTIME: | |
322 | base = &alarm_bases[ALARM_BOOTTIME]; | |
323 | type = ALARM_BOOTTIME_FREEZER; | |
324 | break; | |
325 | default: | |
326 | WARN_ONCE(1, "Invalid alarm type: %d\n", type); | |
327 | return; | |
328 | } | |
9a7adcf5 JS |
329 | |
330 | delta = ktime_sub(absexp, base->gettime()); | |
331 | ||
332 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
2456e855 | 333 | if (!freezer_delta || (delta < freezer_delta)) { |
9a7adcf5 | 334 | freezer_delta = delta; |
4a057549 BW |
335 | freezer_expires = absexp; |
336 | freezer_alarmtype = type; | |
337 | } | |
9a7adcf5 JS |
338 | spin_unlock_irqrestore(&freezer_delta_lock, flags); |
339 | } | |
340 | ||
341 | ||
180bf812 | 342 | /** |
ff3ead96 JS |
343 | * alarm_init - Initialize an alarm structure |
344 | * @alarm: ptr to alarm to be initialized | |
345 | * @type: the type of the alarm | |
346 | * @function: callback that is run when the alarm fires | |
ff3ead96 JS |
347 | */ |
348 | void alarm_init(struct alarm *alarm, enum alarmtimer_type type, | |
4b41308d | 349 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) |
ff3ead96 JS |
350 | { |
351 | timerqueue_init(&alarm->node); | |
dae373be JS |
352 | hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid, |
353 | HRTIMER_MODE_ABS); | |
354 | alarm->timer.function = alarmtimer_fired; | |
ff3ead96 JS |
355 | alarm->function = function; |
356 | alarm->type = type; | |
a28cde81 | 357 | alarm->state = ALARMTIMER_STATE_INACTIVE; |
ff3ead96 | 358 | } |
11682a41 | 359 | EXPORT_SYMBOL_GPL(alarm_init); |
ff3ead96 | 360 | |
180bf812 | 361 | /** |
6cffe00f | 362 | * alarm_start - Sets an absolute alarm to fire |
ff3ead96 JS |
363 | * @alarm: ptr to alarm to set |
364 | * @start: time to run the alarm | |
ff3ead96 | 365 | */ |
b193217e | 366 | void alarm_start(struct alarm *alarm, ktime_t start) |
ff3ead96 JS |
367 | { |
368 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
369 | unsigned long flags; | |
370 | ||
371 | spin_lock_irqsave(&base->lock, flags); | |
ff3ead96 | 372 | alarm->node.expires = start; |
ff3ead96 | 373 | alarmtimer_enqueue(base, alarm); |
b193217e | 374 | hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS); |
ff3ead96 | 375 | spin_unlock_irqrestore(&base->lock, flags); |
4a057549 BW |
376 | |
377 | trace_alarmtimer_start(alarm, base->gettime()); | |
ff3ead96 | 378 | } |
11682a41 | 379 | EXPORT_SYMBOL_GPL(alarm_start); |
ff3ead96 | 380 | |
6cffe00f TP |
381 | /** |
382 | * alarm_start_relative - Sets a relative alarm to fire | |
383 | * @alarm: ptr to alarm to set | |
384 | * @start: time relative to now to run the alarm | |
385 | */ | |
b193217e | 386 | void alarm_start_relative(struct alarm *alarm, ktime_t start) |
6cffe00f TP |
387 | { |
388 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
389 | ||
390 | start = ktime_add(start, base->gettime()); | |
b193217e | 391 | alarm_start(alarm, start); |
6cffe00f | 392 | } |
11682a41 | 393 | EXPORT_SYMBOL_GPL(alarm_start_relative); |
6cffe00f TP |
394 | |
395 | void alarm_restart(struct alarm *alarm) | |
396 | { | |
397 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
398 | unsigned long flags; | |
399 | ||
400 | spin_lock_irqsave(&base->lock, flags); | |
401 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); | |
402 | hrtimer_restart(&alarm->timer); | |
403 | alarmtimer_enqueue(base, alarm); | |
404 | spin_unlock_irqrestore(&base->lock, flags); | |
405 | } | |
11682a41 | 406 | EXPORT_SYMBOL_GPL(alarm_restart); |
6cffe00f | 407 | |
180bf812 | 408 | /** |
9082c465 | 409 | * alarm_try_to_cancel - Tries to cancel an alarm timer |
ff3ead96 | 410 | * @alarm: ptr to alarm to be canceled |
9082c465 JS |
411 | * |
412 | * Returns 1 if the timer was canceled, 0 if it was not running, | |
413 | * and -1 if the callback was running | |
ff3ead96 | 414 | */ |
9082c465 | 415 | int alarm_try_to_cancel(struct alarm *alarm) |
ff3ead96 JS |
416 | { |
417 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
418 | unsigned long flags; | |
dae373be | 419 | int ret; |
9082c465 | 420 | |
dae373be JS |
421 | spin_lock_irqsave(&base->lock, flags); |
422 | ret = hrtimer_try_to_cancel(&alarm->timer); | |
423 | if (ret >= 0) | |
a65bcc12 | 424 | alarmtimer_dequeue(base, alarm); |
ff3ead96 | 425 | spin_unlock_irqrestore(&base->lock, flags); |
4a057549 BW |
426 | |
427 | trace_alarmtimer_cancel(alarm, base->gettime()); | |
9082c465 | 428 | return ret; |
ff3ead96 | 429 | } |
11682a41 | 430 | EXPORT_SYMBOL_GPL(alarm_try_to_cancel); |
ff3ead96 JS |
431 | |
432 | ||
9082c465 JS |
433 | /** |
434 | * alarm_cancel - Spins trying to cancel an alarm timer until it is done | |
435 | * @alarm: ptr to alarm to be canceled | |
436 | * | |
437 | * Returns 1 if the timer was canceled, 0 if it was not active. | |
438 | */ | |
439 | int alarm_cancel(struct alarm *alarm) | |
440 | { | |
441 | for (;;) { | |
442 | int ret = alarm_try_to_cancel(alarm); | |
443 | if (ret >= 0) | |
444 | return ret; | |
445 | cpu_relax(); | |
446 | } | |
447 | } | |
11682a41 | 448 | EXPORT_SYMBOL_GPL(alarm_cancel); |
9082c465 | 449 | |
dce75a8c JS |
450 | |
451 | u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) | |
452 | { | |
453 | u64 overrun = 1; | |
454 | ktime_t delta; | |
455 | ||
456 | delta = ktime_sub(now, alarm->node.expires); | |
457 | ||
2456e855 | 458 | if (delta < 0) |
dce75a8c JS |
459 | return 0; |
460 | ||
2456e855 | 461 | if (unlikely(delta >= interval)) { |
dce75a8c JS |
462 | s64 incr = ktime_to_ns(interval); |
463 | ||
464 | overrun = ktime_divns(delta, incr); | |
465 | ||
466 | alarm->node.expires = ktime_add_ns(alarm->node.expires, | |
467 | incr*overrun); | |
468 | ||
2456e855 | 469 | if (alarm->node.expires > now) |
dce75a8c JS |
470 | return overrun; |
471 | /* | |
472 | * This (and the ktime_add() below) is the | |
473 | * correction for exact: | |
474 | */ | |
475 | overrun++; | |
476 | } | |
477 | ||
478 | alarm->node.expires = ktime_add(alarm->node.expires, interval); | |
479 | return overrun; | |
480 | } | |
11682a41 | 481 | EXPORT_SYMBOL_GPL(alarm_forward); |
dce75a8c | 482 | |
6cffe00f TP |
483 | u64 alarm_forward_now(struct alarm *alarm, ktime_t interval) |
484 | { | |
485 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
486 | ||
487 | return alarm_forward(alarm, base->gettime(), interval); | |
488 | } | |
11682a41 | 489 | EXPORT_SYMBOL_GPL(alarm_forward_now); |
dce75a8c JS |
490 | |
491 | ||
180bf812 | 492 | /** |
9a7adcf5 JS |
493 | * clock2alarm - helper that converts from clockid to alarmtypes |
494 | * @clockid: clockid. | |
9a7adcf5 JS |
495 | */ |
496 | static enum alarmtimer_type clock2alarm(clockid_t clockid) | |
497 | { | |
498 | if (clockid == CLOCK_REALTIME_ALARM) | |
499 | return ALARM_REALTIME; | |
500 | if (clockid == CLOCK_BOOTTIME_ALARM) | |
501 | return ALARM_BOOTTIME; | |
502 | return -1; | |
503 | } | |
504 | ||
180bf812 | 505 | /** |
9a7adcf5 JS |
506 | * alarm_handle_timer - Callback for posix timers |
507 | * @alarm: alarm that fired | |
508 | * | |
509 | * Posix timer callback for expired alarm timers. | |
510 | */ | |
4b41308d JS |
511 | static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm, |
512 | ktime_t now) | |
9a7adcf5 | 513 | { |
474e941b | 514 | unsigned long flags; |
9a7adcf5 | 515 | struct k_itimer *ptr = container_of(alarm, struct k_itimer, |
9e264762 | 516 | it.alarm.alarmtimer); |
474e941b RL |
517 | enum alarmtimer_restart result = ALARMTIMER_NORESTART; |
518 | ||
519 | spin_lock_irqsave(&ptr->it_lock, flags); | |
265b81d2 | 520 | if ((ptr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) { |
b6f8a92c NP |
521 | if (IS_ENABLED(CONFIG_POSIX_TIMERS) && |
522 | posix_timer_event(ptr, 0) != 0) | |
265b81d2 RL |
523 | ptr->it_overrun++; |
524 | } | |
4b41308d | 525 | |
54da23b7 | 526 | /* Re-add periodic timers */ |
2456e855 | 527 | if (ptr->it.alarm.interval) { |
9e264762 JS |
528 | ptr->it_overrun += alarm_forward(alarm, now, |
529 | ptr->it.alarm.interval); | |
474e941b | 530 | result = ALARMTIMER_RESTART; |
54da23b7 | 531 | } |
474e941b RL |
532 | spin_unlock_irqrestore(&ptr->it_lock, flags); |
533 | ||
534 | return result; | |
9a7adcf5 JS |
535 | } |
536 | ||
180bf812 | 537 | /** |
9a7adcf5 JS |
538 | * alarm_clock_getres - posix getres interface |
539 | * @which_clock: clockid | |
540 | * @tp: timespec to fill | |
541 | * | |
542 | * Returns the granularity of underlying alarm base clock | |
543 | */ | |
d2e3e0ca | 544 | static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp) |
9a7adcf5 | 545 | { |
1c6b39ad | 546 | if (!alarmtimer_get_rtcdev()) |
98d6f4dd | 547 | return -EINVAL; |
1c6b39ad | 548 | |
056a3cac TG |
549 | tp->tv_sec = 0; |
550 | tp->tv_nsec = hrtimer_resolution; | |
551 | return 0; | |
9a7adcf5 JS |
552 | } |
553 | ||
554 | /** | |
555 | * alarm_clock_get - posix clock_get interface | |
556 | * @which_clock: clockid | |
557 | * @tp: timespec to fill. | |
558 | * | |
559 | * Provides the underlying alarm base time. | |
560 | */ | |
3c9c12f4 | 561 | static int alarm_clock_get(clockid_t which_clock, struct timespec64 *tp) |
9a7adcf5 JS |
562 | { |
563 | struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; | |
564 | ||
1c6b39ad | 565 | if (!alarmtimer_get_rtcdev()) |
98d6f4dd | 566 | return -EINVAL; |
1c6b39ad | 567 | |
3c9c12f4 | 568 | *tp = ktime_to_timespec64(base->gettime()); |
9a7adcf5 JS |
569 | return 0; |
570 | } | |
571 | ||
572 | /** | |
573 | * alarm_timer_create - posix timer_create interface | |
574 | * @new_timer: k_itimer pointer to manage | |
575 | * | |
576 | * Initializes the k_itimer structure. | |
577 | */ | |
578 | static int alarm_timer_create(struct k_itimer *new_timer) | |
579 | { | |
580 | enum alarmtimer_type type; | |
9a7adcf5 | 581 | |
1c6b39ad JS |
582 | if (!alarmtimer_get_rtcdev()) |
583 | return -ENOTSUPP; | |
584 | ||
9a7adcf5 JS |
585 | if (!capable(CAP_WAKE_ALARM)) |
586 | return -EPERM; | |
587 | ||
588 | type = clock2alarm(new_timer->it_clock); | |
9e264762 | 589 | alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer); |
9a7adcf5 JS |
590 | return 0; |
591 | } | |
592 | ||
593 | /** | |
594 | * alarm_timer_get - posix timer_get interface | |
595 | * @new_timer: k_itimer pointer | |
596 | * @cur_setting: itimerspec data to fill | |
597 | * | |
e86fea76 | 598 | * Copies out the current itimerspec data |
9a7adcf5 JS |
599 | */ |
600 | static void alarm_timer_get(struct k_itimer *timr, | |
5f252b32 | 601 | struct itimerspec64 *cur_setting) |
9a7adcf5 | 602 | { |
e86fea76 RL |
603 | ktime_t relative_expiry_time = |
604 | alarm_expires_remaining(&(timr->it.alarm.alarmtimer)); | |
605 | ||
606 | if (ktime_to_ns(relative_expiry_time) > 0) { | |
5f252b32 | 607 | cur_setting->it_value = ktime_to_timespec64(relative_expiry_time); |
e86fea76 RL |
608 | } else { |
609 | cur_setting->it_value.tv_sec = 0; | |
610 | cur_setting->it_value.tv_nsec = 0; | |
611 | } | |
ea7802f6 | 612 | |
5f252b32 | 613 | cur_setting->it_interval = ktime_to_timespec64(timr->it.alarm.interval); |
9a7adcf5 JS |
614 | } |
615 | ||
616 | /** | |
617 | * alarm_timer_del - posix timer_del interface | |
618 | * @timr: k_itimer pointer to be deleted | |
619 | * | |
620 | * Cancels any programmed alarms for the given timer. | |
621 | */ | |
622 | static int alarm_timer_del(struct k_itimer *timr) | |
623 | { | |
1c6b39ad JS |
624 | if (!rtcdev) |
625 | return -ENOTSUPP; | |
626 | ||
9082c465 JS |
627 | if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0) |
628 | return TIMER_RETRY; | |
629 | ||
9a7adcf5 JS |
630 | return 0; |
631 | } | |
632 | ||
633 | /** | |
634 | * alarm_timer_set - posix timer_set interface | |
635 | * @timr: k_itimer pointer to be deleted | |
636 | * @flags: timer flags | |
637 | * @new_setting: itimerspec to be used | |
638 | * @old_setting: itimerspec being replaced | |
639 | * | |
640 | * Sets the timer to new_setting, and starts the timer. | |
641 | */ | |
642 | static int alarm_timer_set(struct k_itimer *timr, int flags, | |
5f252b32 DD |
643 | struct itimerspec64 *new_setting, |
644 | struct itimerspec64 *old_setting) | |
9a7adcf5 | 645 | { |
16927776 JS |
646 | ktime_t exp; |
647 | ||
1c6b39ad JS |
648 | if (!rtcdev) |
649 | return -ENOTSUPP; | |
650 | ||
16927776 JS |
651 | if (flags & ~TIMER_ABSTIME) |
652 | return -EINVAL; | |
653 | ||
971c90bf JS |
654 | if (old_setting) |
655 | alarm_timer_get(timr, old_setting); | |
9a7adcf5 JS |
656 | |
657 | /* If the timer was already set, cancel it */ | |
9082c465 JS |
658 | if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0) |
659 | return TIMER_RETRY; | |
9a7adcf5 JS |
660 | |
661 | /* start the timer */ | |
5f252b32 DD |
662 | timr->it.alarm.interval = timespec64_to_ktime(new_setting->it_interval); |
663 | exp = timespec64_to_ktime(new_setting->it_value); | |
16927776 JS |
664 | /* Convert (if necessary) to absolute time */ |
665 | if (flags != TIMER_ABSTIME) { | |
666 | ktime_t now; | |
667 | ||
668 | now = alarm_bases[timr->it.alarm.alarmtimer.type].gettime(); | |
669 | exp = ktime_add(now, exp); | |
670 | } | |
671 | ||
672 | alarm_start(&timr->it.alarm.alarmtimer, exp); | |
9a7adcf5 JS |
673 | return 0; |
674 | } | |
675 | ||
676 | /** | |
677 | * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep | |
678 | * @alarm: ptr to alarm that fired | |
679 | * | |
680 | * Wakes up the task that set the alarmtimer | |
681 | */ | |
4b41308d JS |
682 | static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm, |
683 | ktime_t now) | |
9a7adcf5 JS |
684 | { |
685 | struct task_struct *task = (struct task_struct *)alarm->data; | |
686 | ||
687 | alarm->data = NULL; | |
688 | if (task) | |
689 | wake_up_process(task); | |
4b41308d | 690 | return ALARMTIMER_NORESTART; |
9a7adcf5 JS |
691 | } |
692 | ||
693 | /** | |
694 | * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation | |
695 | * @alarm: ptr to alarmtimer | |
696 | * @absexp: absolute expiration time | |
697 | * | |
698 | * Sets the alarm timer and sleeps until it is fired or interrupted. | |
699 | */ | |
700 | static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp) | |
701 | { | |
702 | alarm->data = (void *)current; | |
703 | do { | |
704 | set_current_state(TASK_INTERRUPTIBLE); | |
9e264762 | 705 | alarm_start(alarm, absexp); |
9a7adcf5 JS |
706 | if (likely(alarm->data)) |
707 | schedule(); | |
708 | ||
709 | alarm_cancel(alarm); | |
710 | } while (alarm->data && !signal_pending(current)); | |
711 | ||
712 | __set_current_state(TASK_RUNNING); | |
713 | ||
714 | return (alarm->data == NULL); | |
715 | } | |
716 | ||
717 | ||
718 | /** | |
719 | * update_rmtp - Update remaining timespec value | |
720 | * @exp: expiration time | |
721 | * @type: timer type | |
722 | * @rmtp: user pointer to remaining timepsec value | |
723 | * | |
724 | * Helper function that fills in rmtp value with time between | |
725 | * now and the exp value | |
726 | */ | |
727 | static int update_rmtp(ktime_t exp, enum alarmtimer_type type, | |
728 | struct timespec __user *rmtp) | |
729 | { | |
730 | struct timespec rmt; | |
731 | ktime_t rem; | |
732 | ||
733 | rem = ktime_sub(exp, alarm_bases[type].gettime()); | |
734 | ||
2456e855 | 735 | if (rem <= 0) |
9a7adcf5 JS |
736 | return 0; |
737 | rmt = ktime_to_timespec(rem); | |
738 | ||
739 | if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) | |
740 | return -EFAULT; | |
741 | ||
742 | return 1; | |
743 | ||
744 | } | |
745 | ||
746 | /** | |
747 | * alarm_timer_nsleep_restart - restartblock alarmtimer nsleep | |
748 | * @restart: ptr to restart block | |
749 | * | |
750 | * Handles restarted clock_nanosleep calls | |
751 | */ | |
752 | static long __sched alarm_timer_nsleep_restart(struct restart_block *restart) | |
753 | { | |
ab8177bc | 754 | enum alarmtimer_type type = restart->nanosleep.clockid; |
9a7adcf5 JS |
755 | ktime_t exp; |
756 | struct timespec __user *rmtp; | |
757 | struct alarm alarm; | |
758 | int ret = 0; | |
759 | ||
2456e855 | 760 | exp = restart->nanosleep.expires; |
9a7adcf5 JS |
761 | alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); |
762 | ||
763 | if (alarmtimer_do_nsleep(&alarm, exp)) | |
764 | goto out; | |
765 | ||
766 | if (freezing(current)) | |
767 | alarmtimer_freezerset(exp, type); | |
768 | ||
769 | rmtp = restart->nanosleep.rmtp; | |
770 | if (rmtp) { | |
771 | ret = update_rmtp(exp, type, rmtp); | |
772 | if (ret <= 0) | |
773 | goto out; | |
774 | } | |
775 | ||
776 | ||
777 | /* The other values in restart are already filled in */ | |
778 | ret = -ERESTART_RESTARTBLOCK; | |
779 | out: | |
780 | return ret; | |
781 | } | |
782 | ||
783 | /** | |
784 | * alarm_timer_nsleep - alarmtimer nanosleep | |
785 | * @which_clock: clockid | |
786 | * @flags: determins abstime or relative | |
787 | * @tsreq: requested sleep time (abs or rel) | |
788 | * @rmtp: remaining sleep time saved | |
789 | * | |
790 | * Handles clock_nanosleep calls against _ALARM clockids | |
791 | */ | |
792 | static int alarm_timer_nsleep(const clockid_t which_clock, int flags, | |
793 | struct timespec *tsreq, struct timespec __user *rmtp) | |
794 | { | |
795 | enum alarmtimer_type type = clock2alarm(which_clock); | |
796 | struct alarm alarm; | |
797 | ktime_t exp; | |
798 | int ret = 0; | |
799 | struct restart_block *restart; | |
800 | ||
1c6b39ad JS |
801 | if (!alarmtimer_get_rtcdev()) |
802 | return -ENOTSUPP; | |
803 | ||
16927776 JS |
804 | if (flags & ~TIMER_ABSTIME) |
805 | return -EINVAL; | |
806 | ||
9a7adcf5 JS |
807 | if (!capable(CAP_WAKE_ALARM)) |
808 | return -EPERM; | |
809 | ||
810 | alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); | |
811 | ||
812 | exp = timespec_to_ktime(*tsreq); | |
813 | /* Convert (if necessary) to absolute time */ | |
814 | if (flags != TIMER_ABSTIME) { | |
815 | ktime_t now = alarm_bases[type].gettime(); | |
816 | exp = ktime_add(now, exp); | |
817 | } | |
818 | ||
819 | if (alarmtimer_do_nsleep(&alarm, exp)) | |
820 | goto out; | |
821 | ||
822 | if (freezing(current)) | |
823 | alarmtimer_freezerset(exp, type); | |
824 | ||
825 | /* abs timers don't set remaining time or restart */ | |
826 | if (flags == TIMER_ABSTIME) { | |
827 | ret = -ERESTARTNOHAND; | |
828 | goto out; | |
829 | } | |
830 | ||
831 | if (rmtp) { | |
832 | ret = update_rmtp(exp, type, rmtp); | |
833 | if (ret <= 0) | |
834 | goto out; | |
835 | } | |
836 | ||
f56141e3 | 837 | restart = ¤t->restart_block; |
9a7adcf5 | 838 | restart->fn = alarm_timer_nsleep_restart; |
ab8177bc | 839 | restart->nanosleep.clockid = type; |
2456e855 | 840 | restart->nanosleep.expires = exp; |
9a7adcf5 JS |
841 | restart->nanosleep.rmtp = rmtp; |
842 | ret = -ERESTART_RESTARTBLOCK; | |
843 | ||
844 | out: | |
845 | return ret; | |
846 | } | |
ff3ead96 | 847 | |
ff3ead96 JS |
848 | |
849 | /* Suspend hook structures */ | |
850 | static const struct dev_pm_ops alarmtimer_pm_ops = { | |
851 | .suspend = alarmtimer_suspend, | |
a0e3213f | 852 | .resume = alarmtimer_resume, |
ff3ead96 JS |
853 | }; |
854 | ||
855 | static struct platform_driver alarmtimer_driver = { | |
856 | .driver = { | |
857 | .name = "alarmtimer", | |
858 | .pm = &alarmtimer_pm_ops, | |
859 | } | |
860 | }; | |
861 | ||
862 | /** | |
863 | * alarmtimer_init - Initialize alarm timer code | |
864 | * | |
865 | * This function initializes the alarm bases and registers | |
866 | * the posix clock ids. | |
867 | */ | |
868 | static int __init alarmtimer_init(void) | |
869 | { | |
4523f6ad | 870 | struct platform_device *pdev; |
ff3ead96 JS |
871 | int error = 0; |
872 | int i; | |
9a7adcf5 JS |
873 | struct k_clock alarm_clock = { |
874 | .clock_getres = alarm_clock_getres, | |
875 | .clock_get = alarm_clock_get, | |
876 | .timer_create = alarm_timer_create, | |
877 | .timer_set = alarm_timer_set, | |
878 | .timer_del = alarm_timer_del, | |
879 | .timer_get = alarm_timer_get, | |
880 | .nsleep = alarm_timer_nsleep, | |
881 | }; | |
882 | ||
c5e14e76 | 883 | alarmtimer_rtc_timer_init(); |
ad30dfa9 | 884 | |
baa73d9e NP |
885 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { |
886 | posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock); | |
887 | posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock); | |
888 | } | |
ff3ead96 JS |
889 | |
890 | /* Initialize alarm bases */ | |
891 | alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; | |
892 | alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real; | |
893 | alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; | |
894 | alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime; | |
895 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
896 | timerqueue_init_head(&alarm_bases[i].timerqueue); | |
897 | spin_lock_init(&alarm_bases[i].lock); | |
ff3ead96 | 898 | } |
8bc0dafb | 899 | |
4523f6ad TG |
900 | error = alarmtimer_rtc_interface_setup(); |
901 | if (error) | |
902 | return error; | |
903 | ||
ff3ead96 | 904 | error = platform_driver_register(&alarmtimer_driver); |
4523f6ad TG |
905 | if (error) |
906 | goto out_if; | |
ff3ead96 | 907 | |
4523f6ad TG |
908 | pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0); |
909 | if (IS_ERR(pdev)) { | |
910 | error = PTR_ERR(pdev); | |
911 | goto out_drv; | |
912 | } | |
59a93c27 | 913 | ws = wakeup_source_register("alarmtimer"); |
4523f6ad TG |
914 | return 0; |
915 | ||
916 | out_drv: | |
917 | platform_driver_unregister(&alarmtimer_driver); | |
918 | out_if: | |
919 | alarmtimer_rtc_interface_remove(); | |
ff3ead96 JS |
920 | return error; |
921 | } | |
922 | device_initcall(alarmtimer_init); |