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> | |
22 | #include <linux/alarmtimer.h> | |
23 | #include <linux/mutex.h> | |
24 | #include <linux/platform_device.h> | |
25 | #include <linux/posix-timers.h> | |
26 | #include <linux/workqueue.h> | |
27 | #include <linux/freezer.h> | |
28 | ||
180bf812 JS |
29 | /** |
30 | * struct alarm_base - Alarm timer bases | |
31 | * @lock: Lock for syncrhonized access to the base | |
32 | * @timerqueue: Timerqueue head managing the list of events | |
180bf812 JS |
33 | * @gettime: Function to read the time correlating to the base |
34 | * @base_clockid: clockid for the base | |
180bf812 | 35 | */ |
ff3ead96 JS |
36 | static struct alarm_base { |
37 | spinlock_t lock; | |
38 | struct timerqueue_head timerqueue; | |
ff3ead96 JS |
39 | ktime_t (*gettime)(void); |
40 | clockid_t base_clockid; | |
ff3ead96 JS |
41 | } alarm_bases[ALARM_NUMTYPE]; |
42 | ||
c008ba58 JS |
43 | /* freezer delta & lock used to handle clock_nanosleep triggered wakeups */ |
44 | static ktime_t freezer_delta; | |
45 | static DEFINE_SPINLOCK(freezer_delta_lock); | |
46 | ||
59a93c27 TP |
47 | static struct wakeup_source *ws; |
48 | ||
472647dc | 49 | #ifdef CONFIG_RTC_CLASS |
180bf812 | 50 | /* rtc timer and device for setting alarm wakeups at suspend */ |
c5e14e76 | 51 | static struct rtc_timer rtctimer; |
ff3ead96 | 52 | static struct rtc_device *rtcdev; |
c008ba58 | 53 | static DEFINE_SPINLOCK(rtcdev_lock); |
ff3ead96 | 54 | |
c008ba58 JS |
55 | /** |
56 | * alarmtimer_get_rtcdev - Return selected rtcdevice | |
57 | * | |
58 | * This function returns the rtc device to use for wakealarms. | |
59 | * If one has not already been chosen, it checks to see if a | |
60 | * functional rtc device is available. | |
61 | */ | |
57c498fa | 62 | struct rtc_device *alarmtimer_get_rtcdev(void) |
c008ba58 | 63 | { |
c008ba58 JS |
64 | unsigned long flags; |
65 | struct rtc_device *ret; | |
66 | ||
67 | spin_lock_irqsave(&rtcdev_lock, flags); | |
c008ba58 JS |
68 | ret = rtcdev; |
69 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
70 | ||
71 | return ret; | |
72 | } | |
71d5d2b7 | 73 | EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); |
8bc0dafb JS |
74 | |
75 | static int alarmtimer_rtc_add_device(struct device *dev, | |
76 | struct class_interface *class_intf) | |
77 | { | |
78 | unsigned long flags; | |
79 | struct rtc_device *rtc = to_rtc_device(dev); | |
80 | ||
81 | if (rtcdev) | |
82 | return -EBUSY; | |
83 | ||
84 | if (!rtc->ops->set_alarm) | |
85 | return -1; | |
86 | if (!device_may_wakeup(rtc->dev.parent)) | |
87 | return -1; | |
88 | ||
89 | spin_lock_irqsave(&rtcdev_lock, flags); | |
90 | if (!rtcdev) { | |
91 | rtcdev = rtc; | |
92 | /* hold a reference so it doesn't go away */ | |
93 | get_device(dev); | |
94 | } | |
95 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
96 | return 0; | |
97 | } | |
98 | ||
c5e14e76 TG |
99 | static inline void alarmtimer_rtc_timer_init(void) |
100 | { | |
101 | rtc_timer_init(&rtctimer, NULL, NULL); | |
102 | } | |
103 | ||
8bc0dafb JS |
104 | static struct class_interface alarmtimer_rtc_interface = { |
105 | .add_dev = &alarmtimer_rtc_add_device, | |
106 | }; | |
107 | ||
4523f6ad | 108 | static int alarmtimer_rtc_interface_setup(void) |
8bc0dafb JS |
109 | { |
110 | alarmtimer_rtc_interface.class = rtc_class; | |
4523f6ad TG |
111 | return class_interface_register(&alarmtimer_rtc_interface); |
112 | } | |
113 | static void alarmtimer_rtc_interface_remove(void) | |
114 | { | |
115 | class_interface_unregister(&alarmtimer_rtc_interface); | |
8bc0dafb | 116 | } |
1c6b39ad | 117 | #else |
57c498fa | 118 | struct rtc_device *alarmtimer_get_rtcdev(void) |
4523f6ad TG |
119 | { |
120 | return NULL; | |
121 | } | |
122 | #define rtcdev (NULL) | |
123 | static inline int alarmtimer_rtc_interface_setup(void) { return 0; } | |
124 | static inline void alarmtimer_rtc_interface_remove(void) { } | |
c5e14e76 | 125 | static inline void alarmtimer_rtc_timer_init(void) { } |
c008ba58 | 126 | #endif |
ff3ead96 | 127 | |
180bf812 | 128 | /** |
ff3ead96 JS |
129 | * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue |
130 | * @base: pointer to the base where the timer is being run | |
131 | * @alarm: pointer to alarm being enqueued. | |
132 | * | |
dae373be | 133 | * Adds alarm to a alarm_base timerqueue |
ff3ead96 JS |
134 | * |
135 | * Must hold base->lock when calling. | |
136 | */ | |
137 | static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) | |
138 | { | |
dae373be JS |
139 | if (alarm->state & ALARMTIMER_STATE_ENQUEUED) |
140 | timerqueue_del(&base->timerqueue, &alarm->node); | |
141 | ||
ff3ead96 | 142 | timerqueue_add(&base->timerqueue, &alarm->node); |
a28cde81 | 143 | alarm->state |= ALARMTIMER_STATE_ENQUEUED; |
ff3ead96 JS |
144 | } |
145 | ||
180bf812 | 146 | /** |
a65bcc12 | 147 | * alarmtimer_dequeue - Removes an alarm timer from an alarm_base timerqueue |
ff3ead96 JS |
148 | * @base: pointer to the base where the timer is running |
149 | * @alarm: pointer to alarm being removed | |
150 | * | |
dae373be | 151 | * Removes alarm to a alarm_base timerqueue |
ff3ead96 JS |
152 | * |
153 | * Must hold base->lock when calling. | |
154 | */ | |
a65bcc12 | 155 | static void alarmtimer_dequeue(struct alarm_base *base, struct alarm *alarm) |
ff3ead96 | 156 | { |
a28cde81 JS |
157 | if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) |
158 | return; | |
159 | ||
ff3ead96 | 160 | timerqueue_del(&base->timerqueue, &alarm->node); |
a28cde81 | 161 | alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; |
ff3ead96 JS |
162 | } |
163 | ||
7068b7a1 | 164 | |
180bf812 | 165 | /** |
7068b7a1 JS |
166 | * alarmtimer_fired - Handles alarm hrtimer being fired. |
167 | * @timer: pointer to hrtimer being run | |
ff3ead96 | 168 | * |
180bf812 JS |
169 | * When a alarm timer fires, this runs through the timerqueue to |
170 | * see which alarms expired, and runs those. If there are more alarm | |
171 | * timers queued for the future, we set the hrtimer to fire when | |
172 | * when the next future alarm timer expires. | |
ff3ead96 | 173 | */ |
7068b7a1 | 174 | static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) |
ff3ead96 | 175 | { |
dae373be JS |
176 | struct alarm *alarm = container_of(timer, struct alarm, timer); |
177 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
ff3ead96 | 178 | unsigned long flags; |
7068b7a1 | 179 | int ret = HRTIMER_NORESTART; |
54da23b7 | 180 | int restart = ALARMTIMER_NORESTART; |
ff3ead96 JS |
181 | |
182 | spin_lock_irqsave(&base->lock, flags); | |
a65bcc12 | 183 | alarmtimer_dequeue(base, alarm); |
dae373be | 184 | spin_unlock_irqrestore(&base->lock, flags); |
54da23b7 | 185 | |
dae373be JS |
186 | if (alarm->function) |
187 | restart = alarm->function(alarm, base->gettime()); | |
ff3ead96 | 188 | |
dae373be JS |
189 | spin_lock_irqsave(&base->lock, flags); |
190 | if (restart != ALARMTIMER_NORESTART) { | |
191 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); | |
192 | alarmtimer_enqueue(base, alarm); | |
7068b7a1 | 193 | ret = HRTIMER_RESTART; |
ff3ead96 JS |
194 | } |
195 | spin_unlock_irqrestore(&base->lock, flags); | |
ff3ead96 | 196 | |
7068b7a1 | 197 | return ret; |
ff3ead96 | 198 | |
ff3ead96 JS |
199 | } |
200 | ||
6cffe00f TP |
201 | ktime_t alarm_expires_remaining(const struct alarm *alarm) |
202 | { | |
203 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
204 | return ktime_sub(alarm->node.expires, base->gettime()); | |
205 | } | |
11682a41 | 206 | EXPORT_SYMBOL_GPL(alarm_expires_remaining); |
6cffe00f | 207 | |
472647dc | 208 | #ifdef CONFIG_RTC_CLASS |
180bf812 | 209 | /** |
ff3ead96 JS |
210 | * alarmtimer_suspend - Suspend time callback |
211 | * @dev: unused | |
212 | * @state: unused | |
213 | * | |
214 | * When we are going into suspend, we look through the bases | |
215 | * to see which is the soonest timer to expire. We then | |
216 | * set an rtc timer to fire that far into the future, which | |
217 | * will wake us from suspend. | |
218 | */ | |
219 | static int alarmtimer_suspend(struct device *dev) | |
220 | { | |
221 | struct rtc_time tm; | |
222 | ktime_t min, now; | |
223 | unsigned long flags; | |
c008ba58 | 224 | struct rtc_device *rtc; |
ff3ead96 | 225 | int i; |
59a93c27 | 226 | int ret; |
ff3ead96 JS |
227 | |
228 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
229 | min = freezer_delta; | |
230 | freezer_delta = ktime_set(0, 0); | |
231 | spin_unlock_irqrestore(&freezer_delta_lock, flags); | |
232 | ||
8bc0dafb | 233 | rtc = alarmtimer_get_rtcdev(); |
ff3ead96 | 234 | /* If we have no rtcdev, just return */ |
c008ba58 | 235 | if (!rtc) |
ff3ead96 JS |
236 | return 0; |
237 | ||
238 | /* Find the soonest timer to expire*/ | |
239 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
240 | struct alarm_base *base = &alarm_bases[i]; | |
241 | struct timerqueue_node *next; | |
242 | ktime_t delta; | |
243 | ||
244 | spin_lock_irqsave(&base->lock, flags); | |
245 | next = timerqueue_getnext(&base->timerqueue); | |
246 | spin_unlock_irqrestore(&base->lock, flags); | |
247 | if (!next) | |
248 | continue; | |
249 | delta = ktime_sub(next->expires, base->gettime()); | |
250 | if (!min.tv64 || (delta.tv64 < min.tv64)) | |
251 | min = delta; | |
252 | } | |
253 | if (min.tv64 == 0) | |
254 | return 0; | |
255 | ||
59a93c27 TP |
256 | if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { |
257 | __pm_wakeup_event(ws, 2 * MSEC_PER_SEC); | |
258 | return -EBUSY; | |
259 | } | |
ff3ead96 JS |
260 | |
261 | /* Setup an rtc timer to fire that far in the future */ | |
c008ba58 JS |
262 | rtc_timer_cancel(rtc, &rtctimer); |
263 | rtc_read_time(rtc, &tm); | |
ff3ead96 JS |
264 | now = rtc_tm_to_ktime(tm); |
265 | now = ktime_add(now, min); | |
266 | ||
59a93c27 TP |
267 | /* Set alarm, if in the past reject suspend briefly to handle */ |
268 | ret = rtc_timer_start(rtc, &rtctimer, now, ktime_set(0, 0)); | |
269 | if (ret < 0) | |
270 | __pm_wakeup_event(ws, MSEC_PER_SEC); | |
271 | return ret; | |
ff3ead96 | 272 | } |
a0e3213f | 273 | |
274 | static int alarmtimer_resume(struct device *dev) | |
275 | { | |
276 | struct rtc_device *rtc; | |
277 | ||
278 | rtc = alarmtimer_get_rtcdev(); | |
279 | if (rtc) | |
280 | rtc_timer_cancel(rtc, &rtctimer); | |
281 | return 0; | |
282 | } | |
283 | ||
472647dc JS |
284 | #else |
285 | static int alarmtimer_suspend(struct device *dev) | |
286 | { | |
287 | return 0; | |
288 | } | |
a0e3213f | 289 | |
290 | static int alarmtimer_resume(struct device *dev) | |
291 | { | |
292 | return 0; | |
293 | } | |
472647dc | 294 | #endif |
ff3ead96 | 295 | |
9a7adcf5 JS |
296 | static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) |
297 | { | |
298 | ktime_t delta; | |
299 | unsigned long flags; | |
300 | struct alarm_base *base = &alarm_bases[type]; | |
301 | ||
302 | delta = ktime_sub(absexp, base->gettime()); | |
303 | ||
304 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
305 | if (!freezer_delta.tv64 || (delta.tv64 < freezer_delta.tv64)) | |
306 | freezer_delta = delta; | |
307 | spin_unlock_irqrestore(&freezer_delta_lock, flags); | |
308 | } | |
309 | ||
310 | ||
180bf812 | 311 | /** |
ff3ead96 JS |
312 | * alarm_init - Initialize an alarm structure |
313 | * @alarm: ptr to alarm to be initialized | |
314 | * @type: the type of the alarm | |
315 | * @function: callback that is run when the alarm fires | |
ff3ead96 JS |
316 | */ |
317 | void alarm_init(struct alarm *alarm, enum alarmtimer_type type, | |
4b41308d | 318 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) |
ff3ead96 JS |
319 | { |
320 | timerqueue_init(&alarm->node); | |
dae373be JS |
321 | hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid, |
322 | HRTIMER_MODE_ABS); | |
323 | alarm->timer.function = alarmtimer_fired; | |
ff3ead96 JS |
324 | alarm->function = function; |
325 | alarm->type = type; | |
a28cde81 | 326 | alarm->state = ALARMTIMER_STATE_INACTIVE; |
ff3ead96 | 327 | } |
11682a41 | 328 | EXPORT_SYMBOL_GPL(alarm_init); |
ff3ead96 | 329 | |
180bf812 | 330 | /** |
6cffe00f | 331 | * alarm_start - Sets an absolute alarm to fire |
ff3ead96 JS |
332 | * @alarm: ptr to alarm to set |
333 | * @start: time to run the alarm | |
ff3ead96 | 334 | */ |
b193217e | 335 | void alarm_start(struct alarm *alarm, ktime_t start) |
ff3ead96 JS |
336 | { |
337 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
338 | unsigned long flags; | |
339 | ||
340 | spin_lock_irqsave(&base->lock, flags); | |
ff3ead96 | 341 | alarm->node.expires = start; |
ff3ead96 | 342 | alarmtimer_enqueue(base, alarm); |
b193217e | 343 | hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS); |
ff3ead96 JS |
344 | spin_unlock_irqrestore(&base->lock, flags); |
345 | } | |
11682a41 | 346 | EXPORT_SYMBOL_GPL(alarm_start); |
ff3ead96 | 347 | |
6cffe00f TP |
348 | /** |
349 | * alarm_start_relative - Sets a relative alarm to fire | |
350 | * @alarm: ptr to alarm to set | |
351 | * @start: time relative to now to run the alarm | |
352 | */ | |
b193217e | 353 | void alarm_start_relative(struct alarm *alarm, ktime_t start) |
6cffe00f TP |
354 | { |
355 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
356 | ||
357 | start = ktime_add(start, base->gettime()); | |
b193217e | 358 | alarm_start(alarm, start); |
6cffe00f | 359 | } |
11682a41 | 360 | EXPORT_SYMBOL_GPL(alarm_start_relative); |
6cffe00f TP |
361 | |
362 | void alarm_restart(struct alarm *alarm) | |
363 | { | |
364 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
365 | unsigned long flags; | |
366 | ||
367 | spin_lock_irqsave(&base->lock, flags); | |
368 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); | |
369 | hrtimer_restart(&alarm->timer); | |
370 | alarmtimer_enqueue(base, alarm); | |
371 | spin_unlock_irqrestore(&base->lock, flags); | |
372 | } | |
11682a41 | 373 | EXPORT_SYMBOL_GPL(alarm_restart); |
6cffe00f | 374 | |
180bf812 | 375 | /** |
9082c465 | 376 | * alarm_try_to_cancel - Tries to cancel an alarm timer |
ff3ead96 | 377 | * @alarm: ptr to alarm to be canceled |
9082c465 JS |
378 | * |
379 | * Returns 1 if the timer was canceled, 0 if it was not running, | |
380 | * and -1 if the callback was running | |
ff3ead96 | 381 | */ |
9082c465 | 382 | int alarm_try_to_cancel(struct alarm *alarm) |
ff3ead96 JS |
383 | { |
384 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
385 | unsigned long flags; | |
dae373be | 386 | int ret; |
9082c465 | 387 | |
dae373be JS |
388 | spin_lock_irqsave(&base->lock, flags); |
389 | ret = hrtimer_try_to_cancel(&alarm->timer); | |
390 | if (ret >= 0) | |
a65bcc12 | 391 | alarmtimer_dequeue(base, alarm); |
ff3ead96 | 392 | spin_unlock_irqrestore(&base->lock, flags); |
9082c465 | 393 | return ret; |
ff3ead96 | 394 | } |
11682a41 | 395 | EXPORT_SYMBOL_GPL(alarm_try_to_cancel); |
ff3ead96 JS |
396 | |
397 | ||
9082c465 JS |
398 | /** |
399 | * alarm_cancel - Spins trying to cancel an alarm timer until it is done | |
400 | * @alarm: ptr to alarm to be canceled | |
401 | * | |
402 | * Returns 1 if the timer was canceled, 0 if it was not active. | |
403 | */ | |
404 | int alarm_cancel(struct alarm *alarm) | |
405 | { | |
406 | for (;;) { | |
407 | int ret = alarm_try_to_cancel(alarm); | |
408 | if (ret >= 0) | |
409 | return ret; | |
410 | cpu_relax(); | |
411 | } | |
412 | } | |
11682a41 | 413 | EXPORT_SYMBOL_GPL(alarm_cancel); |
9082c465 | 414 | |
dce75a8c JS |
415 | |
416 | u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) | |
417 | { | |
418 | u64 overrun = 1; | |
419 | ktime_t delta; | |
420 | ||
421 | delta = ktime_sub(now, alarm->node.expires); | |
422 | ||
423 | if (delta.tv64 < 0) | |
424 | return 0; | |
425 | ||
426 | if (unlikely(delta.tv64 >= interval.tv64)) { | |
427 | s64 incr = ktime_to_ns(interval); | |
428 | ||
429 | overrun = ktime_divns(delta, incr); | |
430 | ||
431 | alarm->node.expires = ktime_add_ns(alarm->node.expires, | |
432 | incr*overrun); | |
433 | ||
434 | if (alarm->node.expires.tv64 > now.tv64) | |
435 | return overrun; | |
436 | /* | |
437 | * This (and the ktime_add() below) is the | |
438 | * correction for exact: | |
439 | */ | |
440 | overrun++; | |
441 | } | |
442 | ||
443 | alarm->node.expires = ktime_add(alarm->node.expires, interval); | |
444 | return overrun; | |
445 | } | |
11682a41 | 446 | EXPORT_SYMBOL_GPL(alarm_forward); |
dce75a8c | 447 | |
6cffe00f TP |
448 | u64 alarm_forward_now(struct alarm *alarm, ktime_t interval) |
449 | { | |
450 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
451 | ||
452 | return alarm_forward(alarm, base->gettime(), interval); | |
453 | } | |
11682a41 | 454 | EXPORT_SYMBOL_GPL(alarm_forward_now); |
dce75a8c JS |
455 | |
456 | ||
180bf812 | 457 | /** |
9a7adcf5 JS |
458 | * clock2alarm - helper that converts from clockid to alarmtypes |
459 | * @clockid: clockid. | |
9a7adcf5 JS |
460 | */ |
461 | static enum alarmtimer_type clock2alarm(clockid_t clockid) | |
462 | { | |
463 | if (clockid == CLOCK_REALTIME_ALARM) | |
464 | return ALARM_REALTIME; | |
465 | if (clockid == CLOCK_BOOTTIME_ALARM) | |
466 | return ALARM_BOOTTIME; | |
467 | return -1; | |
468 | } | |
469 | ||
180bf812 | 470 | /** |
9a7adcf5 JS |
471 | * alarm_handle_timer - Callback for posix timers |
472 | * @alarm: alarm that fired | |
473 | * | |
474 | * Posix timer callback for expired alarm timers. | |
475 | */ | |
4b41308d JS |
476 | static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm, |
477 | ktime_t now) | |
9a7adcf5 | 478 | { |
474e941b | 479 | unsigned long flags; |
9a7adcf5 | 480 | struct k_itimer *ptr = container_of(alarm, struct k_itimer, |
9e264762 | 481 | it.alarm.alarmtimer); |
474e941b RL |
482 | enum alarmtimer_restart result = ALARMTIMER_NORESTART; |
483 | ||
484 | spin_lock_irqsave(&ptr->it_lock, flags); | |
265b81d2 RL |
485 | if ((ptr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) { |
486 | if (posix_timer_event(ptr, 0) != 0) | |
487 | ptr->it_overrun++; | |
488 | } | |
4b41308d | 489 | |
54da23b7 | 490 | /* Re-add periodic timers */ |
9e264762 JS |
491 | if (ptr->it.alarm.interval.tv64) { |
492 | ptr->it_overrun += alarm_forward(alarm, now, | |
493 | ptr->it.alarm.interval); | |
474e941b | 494 | result = ALARMTIMER_RESTART; |
54da23b7 | 495 | } |
474e941b RL |
496 | spin_unlock_irqrestore(&ptr->it_lock, flags); |
497 | ||
498 | return result; | |
9a7adcf5 JS |
499 | } |
500 | ||
180bf812 | 501 | /** |
9a7adcf5 JS |
502 | * alarm_clock_getres - posix getres interface |
503 | * @which_clock: clockid | |
504 | * @tp: timespec to fill | |
505 | * | |
506 | * Returns the granularity of underlying alarm base clock | |
507 | */ | |
508 | static int alarm_clock_getres(const clockid_t which_clock, struct timespec *tp) | |
509 | { | |
1c6b39ad | 510 | if (!alarmtimer_get_rtcdev()) |
98d6f4dd | 511 | return -EINVAL; |
1c6b39ad | 512 | |
056a3cac TG |
513 | tp->tv_sec = 0; |
514 | tp->tv_nsec = hrtimer_resolution; | |
515 | return 0; | |
9a7adcf5 JS |
516 | } |
517 | ||
518 | /** | |
519 | * alarm_clock_get - posix clock_get interface | |
520 | * @which_clock: clockid | |
521 | * @tp: timespec to fill. | |
522 | * | |
523 | * Provides the underlying alarm base time. | |
524 | */ | |
525 | static int alarm_clock_get(clockid_t which_clock, struct timespec *tp) | |
526 | { | |
527 | struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; | |
528 | ||
1c6b39ad | 529 | if (!alarmtimer_get_rtcdev()) |
98d6f4dd | 530 | return -EINVAL; |
1c6b39ad | 531 | |
9a7adcf5 JS |
532 | *tp = ktime_to_timespec(base->gettime()); |
533 | return 0; | |
534 | } | |
535 | ||
536 | /** | |
537 | * alarm_timer_create - posix timer_create interface | |
538 | * @new_timer: k_itimer pointer to manage | |
539 | * | |
540 | * Initializes the k_itimer structure. | |
541 | */ | |
542 | static int alarm_timer_create(struct k_itimer *new_timer) | |
543 | { | |
544 | enum alarmtimer_type type; | |
545 | struct alarm_base *base; | |
546 | ||
1c6b39ad JS |
547 | if (!alarmtimer_get_rtcdev()) |
548 | return -ENOTSUPP; | |
549 | ||
9a7adcf5 JS |
550 | if (!capable(CAP_WAKE_ALARM)) |
551 | return -EPERM; | |
552 | ||
553 | type = clock2alarm(new_timer->it_clock); | |
554 | base = &alarm_bases[type]; | |
9e264762 | 555 | alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer); |
9a7adcf5 JS |
556 | return 0; |
557 | } | |
558 | ||
559 | /** | |
560 | * alarm_timer_get - posix timer_get interface | |
561 | * @new_timer: k_itimer pointer | |
562 | * @cur_setting: itimerspec data to fill | |
563 | * | |
e86fea76 | 564 | * Copies out the current itimerspec data |
9a7adcf5 JS |
565 | */ |
566 | static void alarm_timer_get(struct k_itimer *timr, | |
567 | struct itimerspec *cur_setting) | |
568 | { | |
e86fea76 RL |
569 | ktime_t relative_expiry_time = |
570 | alarm_expires_remaining(&(timr->it.alarm.alarmtimer)); | |
571 | ||
572 | if (ktime_to_ns(relative_expiry_time) > 0) { | |
573 | cur_setting->it_value = ktime_to_timespec(relative_expiry_time); | |
574 | } else { | |
575 | cur_setting->it_value.tv_sec = 0; | |
576 | cur_setting->it_value.tv_nsec = 0; | |
577 | } | |
ea7802f6 | 578 | |
e86fea76 | 579 | cur_setting->it_interval = ktime_to_timespec(timr->it.alarm.interval); |
9a7adcf5 JS |
580 | } |
581 | ||
582 | /** | |
583 | * alarm_timer_del - posix timer_del interface | |
584 | * @timr: k_itimer pointer to be deleted | |
585 | * | |
586 | * Cancels any programmed alarms for the given timer. | |
587 | */ | |
588 | static int alarm_timer_del(struct k_itimer *timr) | |
589 | { | |
1c6b39ad JS |
590 | if (!rtcdev) |
591 | return -ENOTSUPP; | |
592 | ||
9082c465 JS |
593 | if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0) |
594 | return TIMER_RETRY; | |
595 | ||
9a7adcf5 JS |
596 | return 0; |
597 | } | |
598 | ||
599 | /** | |
600 | * alarm_timer_set - posix timer_set interface | |
601 | * @timr: k_itimer pointer to be deleted | |
602 | * @flags: timer flags | |
603 | * @new_setting: itimerspec to be used | |
604 | * @old_setting: itimerspec being replaced | |
605 | * | |
606 | * Sets the timer to new_setting, and starts the timer. | |
607 | */ | |
608 | static int alarm_timer_set(struct k_itimer *timr, int flags, | |
609 | struct itimerspec *new_setting, | |
610 | struct itimerspec *old_setting) | |
611 | { | |
16927776 JS |
612 | ktime_t exp; |
613 | ||
1c6b39ad JS |
614 | if (!rtcdev) |
615 | return -ENOTSUPP; | |
616 | ||
16927776 JS |
617 | if (flags & ~TIMER_ABSTIME) |
618 | return -EINVAL; | |
619 | ||
971c90bf JS |
620 | if (old_setting) |
621 | alarm_timer_get(timr, old_setting); | |
9a7adcf5 JS |
622 | |
623 | /* If the timer was already set, cancel it */ | |
9082c465 JS |
624 | if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0) |
625 | return TIMER_RETRY; | |
9a7adcf5 JS |
626 | |
627 | /* start the timer */ | |
9e264762 | 628 | timr->it.alarm.interval = timespec_to_ktime(new_setting->it_interval); |
16927776 JS |
629 | exp = timespec_to_ktime(new_setting->it_value); |
630 | /* Convert (if necessary) to absolute time */ | |
631 | if (flags != TIMER_ABSTIME) { | |
632 | ktime_t now; | |
633 | ||
634 | now = alarm_bases[timr->it.alarm.alarmtimer.type].gettime(); | |
635 | exp = ktime_add(now, exp); | |
636 | } | |
637 | ||
638 | alarm_start(&timr->it.alarm.alarmtimer, exp); | |
9a7adcf5 JS |
639 | return 0; |
640 | } | |
641 | ||
642 | /** | |
643 | * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep | |
644 | * @alarm: ptr to alarm that fired | |
645 | * | |
646 | * Wakes up the task that set the alarmtimer | |
647 | */ | |
4b41308d JS |
648 | static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm, |
649 | ktime_t now) | |
9a7adcf5 JS |
650 | { |
651 | struct task_struct *task = (struct task_struct *)alarm->data; | |
652 | ||
653 | alarm->data = NULL; | |
654 | if (task) | |
655 | wake_up_process(task); | |
4b41308d | 656 | return ALARMTIMER_NORESTART; |
9a7adcf5 JS |
657 | } |
658 | ||
659 | /** | |
660 | * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation | |
661 | * @alarm: ptr to alarmtimer | |
662 | * @absexp: absolute expiration time | |
663 | * | |
664 | * Sets the alarm timer and sleeps until it is fired or interrupted. | |
665 | */ | |
666 | static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp) | |
667 | { | |
668 | alarm->data = (void *)current; | |
669 | do { | |
670 | set_current_state(TASK_INTERRUPTIBLE); | |
9e264762 | 671 | alarm_start(alarm, absexp); |
9a7adcf5 JS |
672 | if (likely(alarm->data)) |
673 | schedule(); | |
674 | ||
675 | alarm_cancel(alarm); | |
676 | } while (alarm->data && !signal_pending(current)); | |
677 | ||
678 | __set_current_state(TASK_RUNNING); | |
679 | ||
680 | return (alarm->data == NULL); | |
681 | } | |
682 | ||
683 | ||
684 | /** | |
685 | * update_rmtp - Update remaining timespec value | |
686 | * @exp: expiration time | |
687 | * @type: timer type | |
688 | * @rmtp: user pointer to remaining timepsec value | |
689 | * | |
690 | * Helper function that fills in rmtp value with time between | |
691 | * now and the exp value | |
692 | */ | |
693 | static int update_rmtp(ktime_t exp, enum alarmtimer_type type, | |
694 | struct timespec __user *rmtp) | |
695 | { | |
696 | struct timespec rmt; | |
697 | ktime_t rem; | |
698 | ||
699 | rem = ktime_sub(exp, alarm_bases[type].gettime()); | |
700 | ||
701 | if (rem.tv64 <= 0) | |
702 | return 0; | |
703 | rmt = ktime_to_timespec(rem); | |
704 | ||
705 | if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) | |
706 | return -EFAULT; | |
707 | ||
708 | return 1; | |
709 | ||
710 | } | |
711 | ||
712 | /** | |
713 | * alarm_timer_nsleep_restart - restartblock alarmtimer nsleep | |
714 | * @restart: ptr to restart block | |
715 | * | |
716 | * Handles restarted clock_nanosleep calls | |
717 | */ | |
718 | static long __sched alarm_timer_nsleep_restart(struct restart_block *restart) | |
719 | { | |
ab8177bc | 720 | enum alarmtimer_type type = restart->nanosleep.clockid; |
9a7adcf5 JS |
721 | ktime_t exp; |
722 | struct timespec __user *rmtp; | |
723 | struct alarm alarm; | |
724 | int ret = 0; | |
725 | ||
726 | exp.tv64 = restart->nanosleep.expires; | |
727 | alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); | |
728 | ||
729 | if (alarmtimer_do_nsleep(&alarm, exp)) | |
730 | goto out; | |
731 | ||
732 | if (freezing(current)) | |
733 | alarmtimer_freezerset(exp, type); | |
734 | ||
735 | rmtp = restart->nanosleep.rmtp; | |
736 | if (rmtp) { | |
737 | ret = update_rmtp(exp, type, rmtp); | |
738 | if (ret <= 0) | |
739 | goto out; | |
740 | } | |
741 | ||
742 | ||
743 | /* The other values in restart are already filled in */ | |
744 | ret = -ERESTART_RESTARTBLOCK; | |
745 | out: | |
746 | return ret; | |
747 | } | |
748 | ||
749 | /** | |
750 | * alarm_timer_nsleep - alarmtimer nanosleep | |
751 | * @which_clock: clockid | |
752 | * @flags: determins abstime or relative | |
753 | * @tsreq: requested sleep time (abs or rel) | |
754 | * @rmtp: remaining sleep time saved | |
755 | * | |
756 | * Handles clock_nanosleep calls against _ALARM clockids | |
757 | */ | |
758 | static int alarm_timer_nsleep(const clockid_t which_clock, int flags, | |
759 | struct timespec *tsreq, struct timespec __user *rmtp) | |
760 | { | |
761 | enum alarmtimer_type type = clock2alarm(which_clock); | |
762 | struct alarm alarm; | |
763 | ktime_t exp; | |
764 | int ret = 0; | |
765 | struct restart_block *restart; | |
766 | ||
1c6b39ad JS |
767 | if (!alarmtimer_get_rtcdev()) |
768 | return -ENOTSUPP; | |
769 | ||
16927776 JS |
770 | if (flags & ~TIMER_ABSTIME) |
771 | return -EINVAL; | |
772 | ||
9a7adcf5 JS |
773 | if (!capable(CAP_WAKE_ALARM)) |
774 | return -EPERM; | |
775 | ||
776 | alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); | |
777 | ||
778 | exp = timespec_to_ktime(*tsreq); | |
779 | /* Convert (if necessary) to absolute time */ | |
780 | if (flags != TIMER_ABSTIME) { | |
781 | ktime_t now = alarm_bases[type].gettime(); | |
782 | exp = ktime_add(now, exp); | |
783 | } | |
784 | ||
785 | if (alarmtimer_do_nsleep(&alarm, exp)) | |
786 | goto out; | |
787 | ||
788 | if (freezing(current)) | |
789 | alarmtimer_freezerset(exp, type); | |
790 | ||
791 | /* abs timers don't set remaining time or restart */ | |
792 | if (flags == TIMER_ABSTIME) { | |
793 | ret = -ERESTARTNOHAND; | |
794 | goto out; | |
795 | } | |
796 | ||
797 | if (rmtp) { | |
798 | ret = update_rmtp(exp, type, rmtp); | |
799 | if (ret <= 0) | |
800 | goto out; | |
801 | } | |
802 | ||
f56141e3 | 803 | restart = ¤t->restart_block; |
9a7adcf5 | 804 | restart->fn = alarm_timer_nsleep_restart; |
ab8177bc | 805 | restart->nanosleep.clockid = type; |
9a7adcf5 JS |
806 | restart->nanosleep.expires = exp.tv64; |
807 | restart->nanosleep.rmtp = rmtp; | |
808 | ret = -ERESTART_RESTARTBLOCK; | |
809 | ||
810 | out: | |
811 | return ret; | |
812 | } | |
ff3ead96 | 813 | |
ff3ead96 JS |
814 | |
815 | /* Suspend hook structures */ | |
816 | static const struct dev_pm_ops alarmtimer_pm_ops = { | |
817 | .suspend = alarmtimer_suspend, | |
a0e3213f | 818 | .resume = alarmtimer_resume, |
ff3ead96 JS |
819 | }; |
820 | ||
821 | static struct platform_driver alarmtimer_driver = { | |
822 | .driver = { | |
823 | .name = "alarmtimer", | |
824 | .pm = &alarmtimer_pm_ops, | |
825 | } | |
826 | }; | |
827 | ||
828 | /** | |
829 | * alarmtimer_init - Initialize alarm timer code | |
830 | * | |
831 | * This function initializes the alarm bases and registers | |
832 | * the posix clock ids. | |
833 | */ | |
834 | static int __init alarmtimer_init(void) | |
835 | { | |
4523f6ad | 836 | struct platform_device *pdev; |
ff3ead96 JS |
837 | int error = 0; |
838 | int i; | |
9a7adcf5 JS |
839 | struct k_clock alarm_clock = { |
840 | .clock_getres = alarm_clock_getres, | |
841 | .clock_get = alarm_clock_get, | |
842 | .timer_create = alarm_timer_create, | |
843 | .timer_set = alarm_timer_set, | |
844 | .timer_del = alarm_timer_del, | |
845 | .timer_get = alarm_timer_get, | |
846 | .nsleep = alarm_timer_nsleep, | |
847 | }; | |
848 | ||
c5e14e76 | 849 | alarmtimer_rtc_timer_init(); |
ad30dfa9 | 850 | |
9a7adcf5 JS |
851 | posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock); |
852 | posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock); | |
ff3ead96 JS |
853 | |
854 | /* Initialize alarm bases */ | |
855 | alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; | |
856 | alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real; | |
857 | alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; | |
858 | alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime; | |
859 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
860 | timerqueue_init_head(&alarm_bases[i].timerqueue); | |
861 | spin_lock_init(&alarm_bases[i].lock); | |
ff3ead96 | 862 | } |
8bc0dafb | 863 | |
4523f6ad TG |
864 | error = alarmtimer_rtc_interface_setup(); |
865 | if (error) | |
866 | return error; | |
867 | ||
ff3ead96 | 868 | error = platform_driver_register(&alarmtimer_driver); |
4523f6ad TG |
869 | if (error) |
870 | goto out_if; | |
ff3ead96 | 871 | |
4523f6ad TG |
872 | pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0); |
873 | if (IS_ERR(pdev)) { | |
874 | error = PTR_ERR(pdev); | |
875 | goto out_drv; | |
876 | } | |
59a93c27 | 877 | ws = wakeup_source_register("alarmtimer"); |
4523f6ad TG |
878 | return 0; |
879 | ||
880 | out_drv: | |
881 | platform_driver_unregister(&alarmtimer_driver); | |
882 | out_if: | |
883 | alarmtimer_rtc_interface_remove(); | |
ff3ead96 JS |
884 | return error; |
885 | } | |
886 | device_initcall(alarmtimer_init); |