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