]>
Commit | Line | Data |
---|---|---|
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> | |
edbeda46 | 30 | #include <linux/compat.h> |
51218298 | 31 | #include <linux/module.h> |
ff3ead96 | 32 | |
bab0aae9 TG |
33 | #include "posix-timers.h" |
34 | ||
4a057549 BW |
35 | #define CREATE_TRACE_POINTS |
36 | #include <trace/events/alarmtimer.h> | |
37 | ||
180bf812 JS |
38 | /** |
39 | * struct alarm_base - Alarm timer bases | |
40 | * @lock: Lock for syncrhonized access to the base | |
41 | * @timerqueue: Timerqueue head managing the list of events | |
180bf812 JS |
42 | * @gettime: Function to read the time correlating to the base |
43 | * @base_clockid: clockid for the base | |
180bf812 | 44 | */ |
ff3ead96 JS |
45 | static struct alarm_base { |
46 | spinlock_t lock; | |
47 | struct timerqueue_head timerqueue; | |
ff3ead96 JS |
48 | ktime_t (*gettime)(void); |
49 | clockid_t base_clockid; | |
ff3ead96 JS |
50 | } alarm_bases[ALARM_NUMTYPE]; |
51 | ||
b6b3b80f | 52 | #if defined(CONFIG_POSIX_TIMERS) || defined(CONFIG_RTC_CLASS) |
4a057549 BW |
53 | /* freezer information to handle clock_nanosleep triggered wakeups */ |
54 | static enum alarmtimer_type freezer_alarmtype; | |
55 | static ktime_t freezer_expires; | |
c008ba58 JS |
56 | static ktime_t freezer_delta; |
57 | static DEFINE_SPINLOCK(freezer_delta_lock); | |
b6b3b80f | 58 | #endif |
c008ba58 | 59 | |
47b4a457 | 60 | #ifdef CONFIG_RTC_CLASS |
59a93c27 TP |
61 | static struct wakeup_source *ws; |
62 | ||
180bf812 | 63 | /* rtc timer and device for setting alarm wakeups at suspend */ |
c5e14e76 | 64 | static struct rtc_timer rtctimer; |
ff3ead96 | 65 | static struct rtc_device *rtcdev; |
c008ba58 | 66 | static DEFINE_SPINLOCK(rtcdev_lock); |
ff3ead96 | 67 | |
c008ba58 JS |
68 | /** |
69 | * alarmtimer_get_rtcdev - Return selected rtcdevice | |
70 | * | |
71 | * This function returns the rtc device to use for wakealarms. | |
72 | * If one has not already been chosen, it checks to see if a | |
73 | * functional rtc device is available. | |
74 | */ | |
57c498fa | 75 | struct rtc_device *alarmtimer_get_rtcdev(void) |
c008ba58 | 76 | { |
c008ba58 JS |
77 | unsigned long flags; |
78 | struct rtc_device *ret; | |
79 | ||
80 | spin_lock_irqsave(&rtcdev_lock, flags); | |
c008ba58 JS |
81 | ret = rtcdev; |
82 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
83 | ||
84 | return ret; | |
85 | } | |
71d5d2b7 | 86 | EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); |
8bc0dafb JS |
87 | |
88 | static int alarmtimer_rtc_add_device(struct device *dev, | |
89 | struct class_interface *class_intf) | |
90 | { | |
91 | unsigned long flags; | |
92 | struct rtc_device *rtc = to_rtc_device(dev); | |
47b4a457 | 93 | struct wakeup_source *__ws; |
8bc0dafb JS |
94 | |
95 | if (rtcdev) | |
96 | return -EBUSY; | |
97 | ||
98 | if (!rtc->ops->set_alarm) | |
99 | return -1; | |
100 | if (!device_may_wakeup(rtc->dev.parent)) | |
101 | return -1; | |
102 | ||
47b4a457 GU |
103 | __ws = wakeup_source_register("alarmtimer"); |
104 | ||
8bc0dafb JS |
105 | spin_lock_irqsave(&rtcdev_lock, flags); |
106 | if (!rtcdev) { | |
51218298 AB |
107 | if (!try_module_get(rtc->owner)) { |
108 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
109 | return -1; | |
110 | } | |
111 | ||
8bc0dafb JS |
112 | rtcdev = rtc; |
113 | /* hold a reference so it doesn't go away */ | |
114 | get_device(dev); | |
47b4a457 GU |
115 | ws = __ws; |
116 | __ws = NULL; | |
8bc0dafb JS |
117 | } |
118 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
47b4a457 GU |
119 | |
120 | wakeup_source_unregister(__ws); | |
121 | ||
8bc0dafb JS |
122 | return 0; |
123 | } | |
124 | ||
c5e14e76 TG |
125 | static inline void alarmtimer_rtc_timer_init(void) |
126 | { | |
127 | rtc_timer_init(&rtctimer, NULL, NULL); | |
128 | } | |
129 | ||
8bc0dafb JS |
130 | static struct class_interface alarmtimer_rtc_interface = { |
131 | .add_dev = &alarmtimer_rtc_add_device, | |
132 | }; | |
133 | ||
4523f6ad | 134 | static int alarmtimer_rtc_interface_setup(void) |
8bc0dafb JS |
135 | { |
136 | alarmtimer_rtc_interface.class = rtc_class; | |
4523f6ad TG |
137 | return class_interface_register(&alarmtimer_rtc_interface); |
138 | } | |
139 | static void alarmtimer_rtc_interface_remove(void) | |
140 | { | |
141 | class_interface_unregister(&alarmtimer_rtc_interface); | |
8bc0dafb | 142 | } |
1c6b39ad | 143 | #else |
57c498fa | 144 | struct rtc_device *alarmtimer_get_rtcdev(void) |
4523f6ad TG |
145 | { |
146 | return NULL; | |
147 | } | |
148 | #define rtcdev (NULL) | |
149 | static inline int alarmtimer_rtc_interface_setup(void) { return 0; } | |
150 | static inline void alarmtimer_rtc_interface_remove(void) { } | |
c5e14e76 | 151 | static inline void alarmtimer_rtc_timer_init(void) { } |
c008ba58 | 152 | #endif |
ff3ead96 | 153 | |
180bf812 | 154 | /** |
ff3ead96 JS |
155 | * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue |
156 | * @base: pointer to the base where the timer is being run | |
157 | * @alarm: pointer to alarm being enqueued. | |
158 | * | |
dae373be | 159 | * Adds alarm to a alarm_base timerqueue |
ff3ead96 JS |
160 | * |
161 | * Must hold base->lock when calling. | |
162 | */ | |
163 | static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) | |
164 | { | |
dae373be JS |
165 | if (alarm->state & ALARMTIMER_STATE_ENQUEUED) |
166 | timerqueue_del(&base->timerqueue, &alarm->node); | |
167 | ||
ff3ead96 | 168 | timerqueue_add(&base->timerqueue, &alarm->node); |
a28cde81 | 169 | alarm->state |= ALARMTIMER_STATE_ENQUEUED; |
ff3ead96 JS |
170 | } |
171 | ||
180bf812 | 172 | /** |
a65bcc12 | 173 | * alarmtimer_dequeue - Removes an alarm timer from an alarm_base timerqueue |
ff3ead96 JS |
174 | * @base: pointer to the base where the timer is running |
175 | * @alarm: pointer to alarm being removed | |
176 | * | |
dae373be | 177 | * Removes alarm to a alarm_base timerqueue |
ff3ead96 JS |
178 | * |
179 | * Must hold base->lock when calling. | |
180 | */ | |
a65bcc12 | 181 | static void alarmtimer_dequeue(struct alarm_base *base, struct alarm *alarm) |
ff3ead96 | 182 | { |
a28cde81 JS |
183 | if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) |
184 | return; | |
185 | ||
ff3ead96 | 186 | timerqueue_del(&base->timerqueue, &alarm->node); |
a28cde81 | 187 | alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; |
ff3ead96 JS |
188 | } |
189 | ||
7068b7a1 | 190 | |
180bf812 | 191 | /** |
7068b7a1 JS |
192 | * alarmtimer_fired - Handles alarm hrtimer being fired. |
193 | * @timer: pointer to hrtimer being run | |
ff3ead96 | 194 | * |
180bf812 JS |
195 | * When a alarm timer fires, this runs through the timerqueue to |
196 | * see which alarms expired, and runs those. If there are more alarm | |
197 | * timers queued for the future, we set the hrtimer to fire when | |
198 | * when the next future alarm timer expires. | |
ff3ead96 | 199 | */ |
7068b7a1 | 200 | static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) |
ff3ead96 | 201 | { |
dae373be JS |
202 | struct alarm *alarm = container_of(timer, struct alarm, timer); |
203 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
ff3ead96 | 204 | unsigned long flags; |
7068b7a1 | 205 | int ret = HRTIMER_NORESTART; |
54da23b7 | 206 | int restart = ALARMTIMER_NORESTART; |
ff3ead96 JS |
207 | |
208 | spin_lock_irqsave(&base->lock, flags); | |
a65bcc12 | 209 | alarmtimer_dequeue(base, alarm); |
dae373be | 210 | spin_unlock_irqrestore(&base->lock, flags); |
54da23b7 | 211 | |
dae373be JS |
212 | if (alarm->function) |
213 | restart = alarm->function(alarm, base->gettime()); | |
ff3ead96 | 214 | |
dae373be JS |
215 | spin_lock_irqsave(&base->lock, flags); |
216 | if (restart != ALARMTIMER_NORESTART) { | |
217 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); | |
218 | alarmtimer_enqueue(base, alarm); | |
7068b7a1 | 219 | ret = HRTIMER_RESTART; |
ff3ead96 JS |
220 | } |
221 | spin_unlock_irqrestore(&base->lock, flags); | |
ff3ead96 | 222 | |
4a057549 | 223 | trace_alarmtimer_fired(alarm, base->gettime()); |
7068b7a1 | 224 | return ret; |
ff3ead96 | 225 | |
ff3ead96 JS |
226 | } |
227 | ||
6cffe00f TP |
228 | ktime_t alarm_expires_remaining(const struct alarm *alarm) |
229 | { | |
230 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
231 | return ktime_sub(alarm->node.expires, base->gettime()); | |
232 | } | |
11682a41 | 233 | EXPORT_SYMBOL_GPL(alarm_expires_remaining); |
6cffe00f | 234 | |
472647dc | 235 | #ifdef CONFIG_RTC_CLASS |
180bf812 | 236 | /** |
ff3ead96 JS |
237 | * alarmtimer_suspend - Suspend time callback |
238 | * @dev: unused | |
239 | * @state: unused | |
240 | * | |
241 | * When we are going into suspend, we look through the bases | |
242 | * to see which is the soonest timer to expire. We then | |
243 | * set an rtc timer to fire that far into the future, which | |
244 | * will wake us from suspend. | |
245 | */ | |
246 | static int alarmtimer_suspend(struct device *dev) | |
247 | { | |
4a057549 BW |
248 | ktime_t min, now, expires; |
249 | int i, ret, type; | |
c008ba58 | 250 | struct rtc_device *rtc; |
4a057549 BW |
251 | unsigned long flags; |
252 | struct rtc_time tm; | |
ff3ead96 JS |
253 | |
254 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
255 | min = freezer_delta; | |
4a057549 BW |
256 | expires = freezer_expires; |
257 | type = freezer_alarmtype; | |
8b0e1953 | 258 | freezer_delta = 0; |
ff3ead96 JS |
259 | spin_unlock_irqrestore(&freezer_delta_lock, flags); |
260 | ||
8bc0dafb | 261 | rtc = alarmtimer_get_rtcdev(); |
ff3ead96 | 262 | /* If we have no rtcdev, just return */ |
c008ba58 | 263 | if (!rtc) |
ff3ead96 JS |
264 | return 0; |
265 | ||
266 | /* Find the soonest timer to expire*/ | |
267 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
268 | struct alarm_base *base = &alarm_bases[i]; | |
269 | struct timerqueue_node *next; | |
270 | ktime_t delta; | |
271 | ||
272 | spin_lock_irqsave(&base->lock, flags); | |
273 | next = timerqueue_getnext(&base->timerqueue); | |
274 | spin_unlock_irqrestore(&base->lock, flags); | |
275 | if (!next) | |
276 | continue; | |
277 | delta = ktime_sub(next->expires, base->gettime()); | |
2456e855 | 278 | if (!min || (delta < min)) { |
4a057549 | 279 | expires = next->expires; |
ff3ead96 | 280 | min = delta; |
4a057549 BW |
281 | type = i; |
282 | } | |
ff3ead96 | 283 | } |
2456e855 | 284 | if (min == 0) |
ff3ead96 JS |
285 | return 0; |
286 | ||
59a93c27 TP |
287 | if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { |
288 | __pm_wakeup_event(ws, 2 * MSEC_PER_SEC); | |
289 | return -EBUSY; | |
290 | } | |
ff3ead96 | 291 | |
4a057549 BW |
292 | trace_alarmtimer_suspend(expires, type); |
293 | ||
ff3ead96 | 294 | /* Setup an rtc timer to fire that far in the future */ |
c008ba58 JS |
295 | rtc_timer_cancel(rtc, &rtctimer); |
296 | rtc_read_time(rtc, &tm); | |
ff3ead96 JS |
297 | now = rtc_tm_to_ktime(tm); |
298 | now = ktime_add(now, min); | |
299 | ||
59a93c27 | 300 | /* Set alarm, if in the past reject suspend briefly to handle */ |
8b0e1953 | 301 | ret = rtc_timer_start(rtc, &rtctimer, now, 0); |
59a93c27 TP |
302 | if (ret < 0) |
303 | __pm_wakeup_event(ws, MSEC_PER_SEC); | |
304 | return ret; | |
ff3ead96 | 305 | } |
a0e3213f | 306 | |
307 | static int alarmtimer_resume(struct device *dev) | |
308 | { | |
309 | struct rtc_device *rtc; | |
310 | ||
311 | rtc = alarmtimer_get_rtcdev(); | |
312 | if (rtc) | |
313 | rtc_timer_cancel(rtc, &rtctimer); | |
314 | return 0; | |
315 | } | |
316 | ||
472647dc JS |
317 | #else |
318 | static int alarmtimer_suspend(struct device *dev) | |
319 | { | |
320 | return 0; | |
321 | } | |
a0e3213f | 322 | |
323 | static int alarmtimer_resume(struct device *dev) | |
324 | { | |
325 | return 0; | |
326 | } | |
472647dc | 327 | #endif |
ff3ead96 | 328 | |
bd031430 TG |
329 | static void |
330 | __alarm_init(struct alarm *alarm, enum alarmtimer_type type, | |
331 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) | |
332 | { | |
333 | timerqueue_init(&alarm->node); | |
334 | alarm->timer.function = alarmtimer_fired; | |
335 | alarm->function = function; | |
336 | alarm->type = type; | |
337 | alarm->state = ALARMTIMER_STATE_INACTIVE; | |
338 | } | |
339 | ||
180bf812 | 340 | /** |
ff3ead96 JS |
341 | * alarm_init - Initialize an alarm structure |
342 | * @alarm: ptr to alarm to be initialized | |
343 | * @type: the type of the alarm | |
344 | * @function: callback that is run when the alarm fires | |
ff3ead96 JS |
345 | */ |
346 | void alarm_init(struct alarm *alarm, enum alarmtimer_type type, | |
4b41308d | 347 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) |
ff3ead96 | 348 | { |
dae373be | 349 | hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid, |
bd031430 TG |
350 | HRTIMER_MODE_ABS); |
351 | __alarm_init(alarm, type, function); | |
ff3ead96 | 352 | } |
11682a41 | 353 | EXPORT_SYMBOL_GPL(alarm_init); |
ff3ead96 | 354 | |
180bf812 | 355 | /** |
6cffe00f | 356 | * alarm_start - Sets an absolute alarm to fire |
ff3ead96 JS |
357 | * @alarm: ptr to alarm to set |
358 | * @start: time to run the alarm | |
ff3ead96 | 359 | */ |
b193217e | 360 | void alarm_start(struct alarm *alarm, ktime_t start) |
ff3ead96 JS |
361 | { |
362 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
363 | unsigned long flags; | |
364 | ||
365 | spin_lock_irqsave(&base->lock, flags); | |
ff3ead96 | 366 | alarm->node.expires = start; |
ff3ead96 | 367 | alarmtimer_enqueue(base, alarm); |
b193217e | 368 | hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS); |
ff3ead96 | 369 | spin_unlock_irqrestore(&base->lock, flags); |
4a057549 BW |
370 | |
371 | trace_alarmtimer_start(alarm, base->gettime()); | |
ff3ead96 | 372 | } |
11682a41 | 373 | EXPORT_SYMBOL_GPL(alarm_start); |
ff3ead96 | 374 | |
6cffe00f TP |
375 | /** |
376 | * alarm_start_relative - Sets a relative alarm to fire | |
377 | * @alarm: ptr to alarm to set | |
378 | * @start: time relative to now to run the alarm | |
379 | */ | |
b193217e | 380 | void alarm_start_relative(struct alarm *alarm, ktime_t start) |
6cffe00f TP |
381 | { |
382 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
383 | ||
f4781e76 | 384 | start = ktime_add_safe(start, base->gettime()); |
b193217e | 385 | alarm_start(alarm, start); |
6cffe00f | 386 | } |
11682a41 | 387 | EXPORT_SYMBOL_GPL(alarm_start_relative); |
6cffe00f TP |
388 | |
389 | void alarm_restart(struct alarm *alarm) | |
390 | { | |
391 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
392 | unsigned long flags; | |
393 | ||
394 | spin_lock_irqsave(&base->lock, flags); | |
395 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); | |
396 | hrtimer_restart(&alarm->timer); | |
397 | alarmtimer_enqueue(base, alarm); | |
398 | spin_unlock_irqrestore(&base->lock, flags); | |
399 | } | |
11682a41 | 400 | EXPORT_SYMBOL_GPL(alarm_restart); |
6cffe00f | 401 | |
180bf812 | 402 | /** |
9082c465 | 403 | * alarm_try_to_cancel - Tries to cancel an alarm timer |
ff3ead96 | 404 | * @alarm: ptr to alarm to be canceled |
9082c465 JS |
405 | * |
406 | * Returns 1 if the timer was canceled, 0 if it was not running, | |
407 | * and -1 if the callback was running | |
ff3ead96 | 408 | */ |
9082c465 | 409 | int alarm_try_to_cancel(struct alarm *alarm) |
ff3ead96 JS |
410 | { |
411 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
412 | unsigned long flags; | |
dae373be | 413 | int ret; |
9082c465 | 414 | |
dae373be JS |
415 | spin_lock_irqsave(&base->lock, flags); |
416 | ret = hrtimer_try_to_cancel(&alarm->timer); | |
417 | if (ret >= 0) | |
a65bcc12 | 418 | alarmtimer_dequeue(base, alarm); |
ff3ead96 | 419 | spin_unlock_irqrestore(&base->lock, flags); |
4a057549 BW |
420 | |
421 | trace_alarmtimer_cancel(alarm, base->gettime()); | |
9082c465 | 422 | return ret; |
ff3ead96 | 423 | } |
11682a41 | 424 | EXPORT_SYMBOL_GPL(alarm_try_to_cancel); |
ff3ead96 JS |
425 | |
426 | ||
9082c465 JS |
427 | /** |
428 | * alarm_cancel - Spins trying to cancel an alarm timer until it is done | |
429 | * @alarm: ptr to alarm to be canceled | |
430 | * | |
431 | * Returns 1 if the timer was canceled, 0 if it was not active. | |
432 | */ | |
433 | int alarm_cancel(struct alarm *alarm) | |
434 | { | |
435 | for (;;) { | |
436 | int ret = alarm_try_to_cancel(alarm); | |
437 | if (ret >= 0) | |
438 | return ret; | |
439 | cpu_relax(); | |
440 | } | |
441 | } | |
11682a41 | 442 | EXPORT_SYMBOL_GPL(alarm_cancel); |
9082c465 | 443 | |
dce75a8c JS |
444 | |
445 | u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) | |
446 | { | |
447 | u64 overrun = 1; | |
448 | ktime_t delta; | |
449 | ||
450 | delta = ktime_sub(now, alarm->node.expires); | |
451 | ||
2456e855 | 452 | if (delta < 0) |
dce75a8c JS |
453 | return 0; |
454 | ||
2456e855 | 455 | if (unlikely(delta >= interval)) { |
dce75a8c JS |
456 | s64 incr = ktime_to_ns(interval); |
457 | ||
458 | overrun = ktime_divns(delta, incr); | |
459 | ||
460 | alarm->node.expires = ktime_add_ns(alarm->node.expires, | |
461 | incr*overrun); | |
462 | ||
2456e855 | 463 | if (alarm->node.expires > now) |
dce75a8c JS |
464 | return overrun; |
465 | /* | |
466 | * This (and the ktime_add() below) is the | |
467 | * correction for exact: | |
468 | */ | |
469 | overrun++; | |
470 | } | |
471 | ||
f4781e76 | 472 | alarm->node.expires = ktime_add_safe(alarm->node.expires, interval); |
dce75a8c JS |
473 | return overrun; |
474 | } | |
11682a41 | 475 | EXPORT_SYMBOL_GPL(alarm_forward); |
dce75a8c | 476 | |
6cffe00f TP |
477 | u64 alarm_forward_now(struct alarm *alarm, ktime_t interval) |
478 | { | |
479 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
480 | ||
481 | return alarm_forward(alarm, base->gettime(), interval); | |
482 | } | |
11682a41 | 483 | EXPORT_SYMBOL_GPL(alarm_forward_now); |
dce75a8c | 484 | |
d3ba5a9a CH |
485 | #ifdef CONFIG_POSIX_TIMERS |
486 | ||
487 | static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) | |
488 | { | |
489 | struct alarm_base *base; | |
490 | unsigned long flags; | |
491 | ktime_t delta; | |
492 | ||
493 | switch(type) { | |
494 | case ALARM_REALTIME: | |
495 | base = &alarm_bases[ALARM_REALTIME]; | |
496 | type = ALARM_REALTIME_FREEZER; | |
497 | break; | |
498 | case ALARM_BOOTTIME: | |
499 | base = &alarm_bases[ALARM_BOOTTIME]; | |
500 | type = ALARM_BOOTTIME_FREEZER; | |
501 | break; | |
502 | default: | |
503 | WARN_ONCE(1, "Invalid alarm type: %d\n", type); | |
504 | return; | |
505 | } | |
506 | ||
507 | delta = ktime_sub(absexp, base->gettime()); | |
508 | ||
509 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
510 | if (!freezer_delta || (delta < freezer_delta)) { | |
511 | freezer_delta = delta; | |
512 | freezer_expires = absexp; | |
513 | freezer_alarmtype = type; | |
514 | } | |
515 | spin_unlock_irqrestore(&freezer_delta_lock, flags); | |
516 | } | |
dce75a8c | 517 | |
180bf812 | 518 | /** |
9a7adcf5 JS |
519 | * clock2alarm - helper that converts from clockid to alarmtypes |
520 | * @clockid: clockid. | |
9a7adcf5 JS |
521 | */ |
522 | static enum alarmtimer_type clock2alarm(clockid_t clockid) | |
523 | { | |
524 | if (clockid == CLOCK_REALTIME_ALARM) | |
525 | return ALARM_REALTIME; | |
526 | if (clockid == CLOCK_BOOTTIME_ALARM) | |
527 | return ALARM_BOOTTIME; | |
528 | return -1; | |
529 | } | |
530 | ||
180bf812 | 531 | /** |
9a7adcf5 JS |
532 | * alarm_handle_timer - Callback for posix timers |
533 | * @alarm: alarm that fired | |
534 | * | |
535 | * Posix timer callback for expired alarm timers. | |
536 | */ | |
4b41308d JS |
537 | static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm, |
538 | ktime_t now) | |
9a7adcf5 JS |
539 | { |
540 | struct k_itimer *ptr = container_of(alarm, struct k_itimer, | |
f2c45807 | 541 | it.alarm.alarmtimer); |
474e941b | 542 | enum alarmtimer_restart result = ALARMTIMER_NORESTART; |
f2c45807 TG |
543 | unsigned long flags; |
544 | int si_private = 0; | |
474e941b RL |
545 | |
546 | spin_lock_irqsave(&ptr->it_lock, flags); | |
4b41308d | 547 | |
f2c45807 TG |
548 | ptr->it_active = 0; |
549 | if (ptr->it_interval) | |
550 | si_private = ++ptr->it_requeue_pending; | |
551 | ||
552 | if (posix_timer_event(ptr, si_private) && ptr->it_interval) { | |
553 | /* | |
554 | * Handle ignored signals and rearm the timer. This will go | |
555 | * away once we handle ignored signals proper. | |
556 | */ | |
557 | ptr->it_overrun += alarm_forward_now(alarm, ptr->it_interval); | |
558 | ++ptr->it_requeue_pending; | |
559 | ptr->it_active = 1; | |
474e941b | 560 | result = ALARMTIMER_RESTART; |
54da23b7 | 561 | } |
474e941b RL |
562 | spin_unlock_irqrestore(&ptr->it_lock, flags); |
563 | ||
564 | return result; | |
9a7adcf5 JS |
565 | } |
566 | ||
b3db80f7 TG |
567 | /** |
568 | * alarm_timer_rearm - Posix timer callback for rearming timer | |
569 | * @timr: Pointer to the posixtimer data struct | |
570 | */ | |
571 | static void alarm_timer_rearm(struct k_itimer *timr) | |
572 | { | |
573 | struct alarm *alarm = &timr->it.alarm.alarmtimer; | |
574 | ||
575 | timr->it_overrun += alarm_forward_now(alarm, timr->it_interval); | |
576 | alarm_start(alarm, alarm->node.expires); | |
577 | } | |
578 | ||
e7561f16 TG |
579 | /** |
580 | * alarm_timer_forward - Posix timer callback for forwarding timer | |
581 | * @timr: Pointer to the posixtimer data struct | |
582 | * @now: Current time to forward the timer against | |
583 | */ | |
584 | static int alarm_timer_forward(struct k_itimer *timr, ktime_t now) | |
585 | { | |
586 | struct alarm *alarm = &timr->it.alarm.alarmtimer; | |
587 | ||
588 | return (int) alarm_forward(alarm, timr->it_interval, now); | |
589 | } | |
590 | ||
d653d845 TG |
591 | /** |
592 | * alarm_timer_remaining - Posix timer callback to retrieve remaining time | |
593 | * @timr: Pointer to the posixtimer data struct | |
594 | * @now: Current time to calculate against | |
595 | */ | |
596 | static ktime_t alarm_timer_remaining(struct k_itimer *timr, ktime_t now) | |
597 | { | |
598 | struct alarm *alarm = &timr->it.alarm.alarmtimer; | |
599 | ||
600 | return ktime_sub(now, alarm->node.expires); | |
601 | } | |
602 | ||
e344c9e7 TG |
603 | /** |
604 | * alarm_timer_try_to_cancel - Posix timer callback to cancel a timer | |
605 | * @timr: Pointer to the posixtimer data struct | |
606 | */ | |
607 | static int alarm_timer_try_to_cancel(struct k_itimer *timr) | |
608 | { | |
609 | return alarm_try_to_cancel(&timr->it.alarm.alarmtimer); | |
610 | } | |
611 | ||
b3bf6f36 TG |
612 | /** |
613 | * alarm_timer_arm - Posix timer callback to arm a timer | |
614 | * @timr: Pointer to the posixtimer data struct | |
615 | * @expires: The new expiry time | |
616 | * @absolute: Expiry value is absolute time | |
617 | * @sigev_none: Posix timer does not deliver signals | |
618 | */ | |
619 | static void alarm_timer_arm(struct k_itimer *timr, ktime_t expires, | |
620 | bool absolute, bool sigev_none) | |
621 | { | |
622 | struct alarm *alarm = &timr->it.alarm.alarmtimer; | |
623 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
624 | ||
625 | if (!absolute) | |
626 | expires = ktime_add_safe(expires, base->gettime()); | |
627 | if (sigev_none) | |
628 | alarm->node.expires = expires; | |
629 | else | |
630 | alarm_start(&timr->it.alarm.alarmtimer, expires); | |
631 | } | |
632 | ||
180bf812 | 633 | /** |
9a7adcf5 JS |
634 | * alarm_clock_getres - posix getres interface |
635 | * @which_clock: clockid | |
636 | * @tp: timespec to fill | |
637 | * | |
638 | * Returns the granularity of underlying alarm base clock | |
639 | */ | |
d2e3e0ca | 640 | static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp) |
9a7adcf5 | 641 | { |
1c6b39ad | 642 | if (!alarmtimer_get_rtcdev()) |
98d6f4dd | 643 | return -EINVAL; |
1c6b39ad | 644 | |
056a3cac TG |
645 | tp->tv_sec = 0; |
646 | tp->tv_nsec = hrtimer_resolution; | |
647 | return 0; | |
9a7adcf5 JS |
648 | } |
649 | ||
650 | /** | |
651 | * alarm_clock_get - posix clock_get interface | |
652 | * @which_clock: clockid | |
653 | * @tp: timespec to fill. | |
654 | * | |
655 | * Provides the underlying alarm base time. | |
656 | */ | |
3c9c12f4 | 657 | static int alarm_clock_get(clockid_t which_clock, struct timespec64 *tp) |
9a7adcf5 JS |
658 | { |
659 | struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; | |
660 | ||
1c6b39ad | 661 | if (!alarmtimer_get_rtcdev()) |
98d6f4dd | 662 | return -EINVAL; |
1c6b39ad | 663 | |
3c9c12f4 | 664 | *tp = ktime_to_timespec64(base->gettime()); |
9a7adcf5 JS |
665 | return 0; |
666 | } | |
667 | ||
668 | /** | |
669 | * alarm_timer_create - posix timer_create interface | |
670 | * @new_timer: k_itimer pointer to manage | |
671 | * | |
672 | * Initializes the k_itimer structure. | |
673 | */ | |
674 | static int alarm_timer_create(struct k_itimer *new_timer) | |
675 | { | |
676 | enum alarmtimer_type type; | |
9a7adcf5 | 677 | |
1c6b39ad JS |
678 | if (!alarmtimer_get_rtcdev()) |
679 | return -ENOTSUPP; | |
680 | ||
9a7adcf5 JS |
681 | if (!capable(CAP_WAKE_ALARM)) |
682 | return -EPERM; | |
683 | ||
684 | type = clock2alarm(new_timer->it_clock); | |
9e264762 | 685 | alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer); |
9a7adcf5 JS |
686 | return 0; |
687 | } | |
688 | ||
9a7adcf5 JS |
689 | /** |
690 | * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep | |
691 | * @alarm: ptr to alarm that fired | |
692 | * | |
693 | * Wakes up the task that set the alarmtimer | |
694 | */ | |
4b41308d JS |
695 | static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm, |
696 | ktime_t now) | |
9a7adcf5 JS |
697 | { |
698 | struct task_struct *task = (struct task_struct *)alarm->data; | |
699 | ||
700 | alarm->data = NULL; | |
701 | if (task) | |
702 | wake_up_process(task); | |
4b41308d | 703 | return ALARMTIMER_NORESTART; |
9a7adcf5 JS |
704 | } |
705 | ||
706 | /** | |
707 | * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation | |
708 | * @alarm: ptr to alarmtimer | |
709 | * @absexp: absolute expiration time | |
710 | * | |
711 | * Sets the alarm timer and sleeps until it is fired or interrupted. | |
712 | */ | |
15f27ce2 AV |
713 | static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp, |
714 | enum alarmtimer_type type) | |
9a7adcf5 | 715 | { |
edbeda46 | 716 | struct restart_block *restart; |
9a7adcf5 JS |
717 | alarm->data = (void *)current; |
718 | do { | |
719 | set_current_state(TASK_INTERRUPTIBLE); | |
9e264762 | 720 | alarm_start(alarm, absexp); |
9a7adcf5 JS |
721 | if (likely(alarm->data)) |
722 | schedule(); | |
723 | ||
724 | alarm_cancel(alarm); | |
725 | } while (alarm->data && !signal_pending(current)); | |
726 | ||
727 | __set_current_state(TASK_RUNNING); | |
728 | ||
bd031430 TG |
729 | destroy_hrtimer_on_stack(&alarm->timer); |
730 | ||
15f27ce2 | 731 | if (!alarm->data) |
9a7adcf5 | 732 | return 0; |
9a7adcf5 | 733 | |
15f27ce2 AV |
734 | if (freezing(current)) |
735 | alarmtimer_freezerset(absexp, type); | |
edbeda46 AV |
736 | restart = ¤t->restart_block; |
737 | if (restart->nanosleep.type != TT_NONE) { | |
c0edd7c9 | 738 | struct timespec64 rmt; |
15f27ce2 | 739 | ktime_t rem; |
9a7adcf5 | 740 | |
15f27ce2 | 741 | rem = ktime_sub(absexp, alarm_bases[type].gettime()); |
9a7adcf5 | 742 | |
15f27ce2 AV |
743 | if (rem <= 0) |
744 | return 0; | |
c0edd7c9 | 745 | rmt = ktime_to_timespec64(rem); |
15f27ce2 | 746 | |
ce41aaf4 | 747 | return nanosleep_copyout(restart, &rmt); |
15f27ce2 AV |
748 | } |
749 | return -ERESTART_RESTARTBLOCK; | |
9a7adcf5 JS |
750 | } |
751 | ||
bd031430 TG |
752 | static void |
753 | alarm_init_on_stack(struct alarm *alarm, enum alarmtimer_type type, | |
754 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) | |
755 | { | |
756 | hrtimer_init_on_stack(&alarm->timer, alarm_bases[type].base_clockid, | |
757 | HRTIMER_MODE_ABS); | |
758 | __alarm_init(alarm, type, function); | |
759 | } | |
760 | ||
9a7adcf5 JS |
761 | /** |
762 | * alarm_timer_nsleep_restart - restartblock alarmtimer nsleep | |
763 | * @restart: ptr to restart block | |
764 | * | |
765 | * Handles restarted clock_nanosleep calls | |
766 | */ | |
767 | static long __sched alarm_timer_nsleep_restart(struct restart_block *restart) | |
768 | { | |
ab8177bc | 769 | enum alarmtimer_type type = restart->nanosleep.clockid; |
15f27ce2 | 770 | ktime_t exp = restart->nanosleep.expires; |
9a7adcf5 | 771 | struct alarm alarm; |
9a7adcf5 | 772 | |
bd031430 | 773 | alarm_init_on_stack(&alarm, type, alarmtimer_nsleep_wakeup); |
9a7adcf5 | 774 | |
15f27ce2 | 775 | return alarmtimer_do_nsleep(&alarm, exp, type); |
9a7adcf5 JS |
776 | } |
777 | ||
778 | /** | |
779 | * alarm_timer_nsleep - alarmtimer nanosleep | |
780 | * @which_clock: clockid | |
781 | * @flags: determins abstime or relative | |
782 | * @tsreq: requested sleep time (abs or rel) | |
783 | * @rmtp: remaining sleep time saved | |
784 | * | |
785 | * Handles clock_nanosleep calls against _ALARM clockids | |
786 | */ | |
787 | static int alarm_timer_nsleep(const clockid_t which_clock, int flags, | |
938e7cf2 | 788 | const struct timespec64 *tsreq) |
9a7adcf5 JS |
789 | { |
790 | enum alarmtimer_type type = clock2alarm(which_clock); | |
15f27ce2 | 791 | struct restart_block *restart = ¤t->restart_block; |
9a7adcf5 JS |
792 | struct alarm alarm; |
793 | ktime_t exp; | |
794 | int ret = 0; | |
9a7adcf5 | 795 | |
1c6b39ad JS |
796 | if (!alarmtimer_get_rtcdev()) |
797 | return -ENOTSUPP; | |
798 | ||
16927776 JS |
799 | if (flags & ~TIMER_ABSTIME) |
800 | return -EINVAL; | |
801 | ||
9a7adcf5 JS |
802 | if (!capable(CAP_WAKE_ALARM)) |
803 | return -EPERM; | |
804 | ||
bd031430 | 805 | alarm_init_on_stack(&alarm, type, alarmtimer_nsleep_wakeup); |
9a7adcf5 | 806 | |
ad196384 | 807 | exp = timespec64_to_ktime(*tsreq); |
9a7adcf5 JS |
808 | /* Convert (if necessary) to absolute time */ |
809 | if (flags != TIMER_ABSTIME) { | |
810 | ktime_t now = alarm_bases[type].gettime(); | |
811 | exp = ktime_add(now, exp); | |
812 | } | |
813 | ||
15f27ce2 AV |
814 | ret = alarmtimer_do_nsleep(&alarm, exp, type); |
815 | if (ret != -ERESTART_RESTARTBLOCK) | |
816 | return ret; | |
9a7adcf5 JS |
817 | |
818 | /* abs timers don't set remaining time or restart */ | |
15f27ce2 AV |
819 | if (flags == TIMER_ABSTIME) |
820 | return -ERESTARTNOHAND; | |
9a7adcf5 | 821 | |
9a7adcf5 | 822 | restart->fn = alarm_timer_nsleep_restart; |
ab8177bc | 823 | restart->nanosleep.clockid = type; |
2456e855 | 824 | restart->nanosleep.expires = exp; |
9a7adcf5 JS |
825 | return ret; |
826 | } | |
ff3ead96 | 827 | |
d3ba5a9a | 828 | const struct k_clock alarm_clock = { |
d653d845 TG |
829 | .clock_getres = alarm_clock_getres, |
830 | .clock_get = alarm_clock_get, | |
831 | .timer_create = alarm_timer_create, | |
f2c45807 TG |
832 | .timer_set = common_timer_set, |
833 | .timer_del = common_timer_del, | |
834 | .timer_get = common_timer_get, | |
b3bf6f36 | 835 | .timer_arm = alarm_timer_arm, |
d653d845 TG |
836 | .timer_rearm = alarm_timer_rearm, |
837 | .timer_forward = alarm_timer_forward, | |
838 | .timer_remaining = alarm_timer_remaining, | |
e344c9e7 | 839 | .timer_try_to_cancel = alarm_timer_try_to_cancel, |
d653d845 | 840 | .nsleep = alarm_timer_nsleep, |
d3ba5a9a CH |
841 | }; |
842 | #endif /* CONFIG_POSIX_TIMERS */ | |
843 | ||
ff3ead96 JS |
844 | |
845 | /* Suspend hook structures */ | |
846 | static const struct dev_pm_ops alarmtimer_pm_ops = { | |
847 | .suspend = alarmtimer_suspend, | |
a0e3213f | 848 | .resume = alarmtimer_resume, |
ff3ead96 JS |
849 | }; |
850 | ||
851 | static struct platform_driver alarmtimer_driver = { | |
852 | .driver = { | |
853 | .name = "alarmtimer", | |
854 | .pm = &alarmtimer_pm_ops, | |
855 | } | |
856 | }; | |
857 | ||
858 | /** | |
859 | * alarmtimer_init - Initialize alarm timer code | |
860 | * | |
861 | * This function initializes the alarm bases and registers | |
862 | * the posix clock ids. | |
863 | */ | |
864 | static int __init alarmtimer_init(void) | |
865 | { | |
4523f6ad | 866 | struct platform_device *pdev; |
ff3ead96 JS |
867 | int error = 0; |
868 | int i; | |
9a7adcf5 | 869 | |
c5e14e76 | 870 | alarmtimer_rtc_timer_init(); |
ad30dfa9 | 871 | |
ff3ead96 JS |
872 | /* Initialize alarm bases */ |
873 | alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; | |
874 | alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real; | |
875 | alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; | |
876 | alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime; | |
877 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
878 | timerqueue_init_head(&alarm_bases[i].timerqueue); | |
879 | spin_lock_init(&alarm_bases[i].lock); | |
ff3ead96 | 880 | } |
8bc0dafb | 881 | |
4523f6ad TG |
882 | error = alarmtimer_rtc_interface_setup(); |
883 | if (error) | |
884 | return error; | |
885 | ||
ff3ead96 | 886 | error = platform_driver_register(&alarmtimer_driver); |
4523f6ad TG |
887 | if (error) |
888 | goto out_if; | |
ff3ead96 | 889 | |
4523f6ad TG |
890 | pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0); |
891 | if (IS_ERR(pdev)) { | |
892 | error = PTR_ERR(pdev); | |
893 | goto out_drv; | |
894 | } | |
895 | return 0; | |
896 | ||
897 | out_drv: | |
898 | platform_driver_unregister(&alarmtimer_driver); | |
899 | out_if: | |
900 | alarmtimer_rtc_interface_remove(); | |
ff3ead96 JS |
901 | return error; |
902 | } | |
903 | device_initcall(alarmtimer_init); |