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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 | ||
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 | |
33 | * @timer: hrtimer used to schedule events while running | |
34 | * @gettime: Function to read the time correlating to the base | |
35 | * @base_clockid: clockid for the base | |
180bf812 | 36 | */ |
ff3ead96 JS |
37 | static struct alarm_base { |
38 | spinlock_t lock; | |
39 | struct timerqueue_head timerqueue; | |
40 | struct hrtimer timer; | |
41 | ktime_t (*gettime)(void); | |
42 | clockid_t base_clockid; | |
ff3ead96 JS |
43 | } alarm_bases[ALARM_NUMTYPE]; |
44 | ||
c008ba58 JS |
45 | /* freezer delta & lock used to handle clock_nanosleep triggered wakeups */ |
46 | static ktime_t freezer_delta; | |
47 | static DEFINE_SPINLOCK(freezer_delta_lock); | |
48 | ||
59a93c27 TP |
49 | static struct wakeup_source *ws; |
50 | ||
472647dc | 51 | #ifdef CONFIG_RTC_CLASS |
180bf812 | 52 | /* rtc timer and device for setting alarm wakeups at suspend */ |
c5e14e76 | 53 | static struct rtc_timer rtctimer; |
ff3ead96 | 54 | static struct rtc_device *rtcdev; |
c008ba58 | 55 | static DEFINE_SPINLOCK(rtcdev_lock); |
ff3ead96 | 56 | |
c008ba58 JS |
57 | /** |
58 | * alarmtimer_get_rtcdev - Return selected rtcdevice | |
59 | * | |
60 | * This function returns the rtc device to use for wakealarms. | |
61 | * If one has not already been chosen, it checks to see if a | |
62 | * functional rtc device is available. | |
63 | */ | |
57c498fa | 64 | struct rtc_device *alarmtimer_get_rtcdev(void) |
c008ba58 | 65 | { |
c008ba58 JS |
66 | unsigned long flags; |
67 | struct rtc_device *ret; | |
68 | ||
69 | spin_lock_irqsave(&rtcdev_lock, flags); | |
c008ba58 JS |
70 | ret = rtcdev; |
71 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
72 | ||
73 | return ret; | |
74 | } | |
8bc0dafb JS |
75 | |
76 | ||
77 | static int alarmtimer_rtc_add_device(struct device *dev, | |
78 | struct class_interface *class_intf) | |
79 | { | |
80 | unsigned long flags; | |
81 | struct rtc_device *rtc = to_rtc_device(dev); | |
82 | ||
83 | if (rtcdev) | |
84 | return -EBUSY; | |
85 | ||
86 | if (!rtc->ops->set_alarm) | |
87 | return -1; | |
88 | if (!device_may_wakeup(rtc->dev.parent)) | |
89 | return -1; | |
90 | ||
91 | spin_lock_irqsave(&rtcdev_lock, flags); | |
92 | if (!rtcdev) { | |
93 | rtcdev = rtc; | |
94 | /* hold a reference so it doesn't go away */ | |
95 | get_device(dev); | |
96 | } | |
97 | spin_unlock_irqrestore(&rtcdev_lock, flags); | |
98 | return 0; | |
99 | } | |
100 | ||
c5e14e76 TG |
101 | static inline void alarmtimer_rtc_timer_init(void) |
102 | { | |
103 | rtc_timer_init(&rtctimer, NULL, NULL); | |
104 | } | |
105 | ||
8bc0dafb JS |
106 | static struct class_interface alarmtimer_rtc_interface = { |
107 | .add_dev = &alarmtimer_rtc_add_device, | |
108 | }; | |
109 | ||
4523f6ad | 110 | static int alarmtimer_rtc_interface_setup(void) |
8bc0dafb JS |
111 | { |
112 | alarmtimer_rtc_interface.class = rtc_class; | |
4523f6ad TG |
113 | return class_interface_register(&alarmtimer_rtc_interface); |
114 | } | |
115 | static void alarmtimer_rtc_interface_remove(void) | |
116 | { | |
117 | class_interface_unregister(&alarmtimer_rtc_interface); | |
8bc0dafb | 118 | } |
1c6b39ad | 119 | #else |
57c498fa | 120 | struct rtc_device *alarmtimer_get_rtcdev(void) |
4523f6ad TG |
121 | { |
122 | return NULL; | |
123 | } | |
124 | #define rtcdev (NULL) | |
125 | static inline int alarmtimer_rtc_interface_setup(void) { return 0; } | |
126 | static inline void alarmtimer_rtc_interface_remove(void) { } | |
c5e14e76 | 127 | static inline void alarmtimer_rtc_timer_init(void) { } |
c008ba58 | 128 | #endif |
ff3ead96 | 129 | |
180bf812 | 130 | /** |
ff3ead96 JS |
131 | * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue |
132 | * @base: pointer to the base where the timer is being run | |
133 | * @alarm: pointer to alarm being enqueued. | |
134 | * | |
135 | * Adds alarm to a alarm_base timerqueue and if necessary sets | |
136 | * an hrtimer to run. | |
137 | * | |
138 | * Must hold base->lock when calling. | |
139 | */ | |
140 | static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) | |
141 | { | |
142 | timerqueue_add(&base->timerqueue, &alarm->node); | |
a28cde81 JS |
143 | alarm->state |= ALARMTIMER_STATE_ENQUEUED; |
144 | ||
ff3ead96 JS |
145 | if (&alarm->node == timerqueue_getnext(&base->timerqueue)) { |
146 | hrtimer_try_to_cancel(&base->timer); | |
147 | hrtimer_start(&base->timer, alarm->node.expires, | |
148 | HRTIMER_MODE_ABS); | |
149 | } | |
150 | } | |
151 | ||
180bf812 | 152 | /** |
ff3ead96 JS |
153 | * alarmtimer_remove - Removes an alarm timer from an alarm_base timerqueue |
154 | * @base: pointer to the base where the timer is running | |
155 | * @alarm: pointer to alarm being removed | |
156 | * | |
157 | * Removes alarm to a alarm_base timerqueue and if necessary sets | |
158 | * a new timer to run. | |
159 | * | |
160 | * Must hold base->lock when calling. | |
161 | */ | |
162 | static void alarmtimer_remove(struct alarm_base *base, struct alarm *alarm) | |
163 | { | |
164 | struct timerqueue_node *next = timerqueue_getnext(&base->timerqueue); | |
165 | ||
a28cde81 JS |
166 | if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) |
167 | return; | |
168 | ||
ff3ead96 | 169 | timerqueue_del(&base->timerqueue, &alarm->node); |
a28cde81 JS |
170 | alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; |
171 | ||
ff3ead96 JS |
172 | if (next == &alarm->node) { |
173 | hrtimer_try_to_cancel(&base->timer); | |
174 | next = timerqueue_getnext(&base->timerqueue); | |
175 | if (!next) | |
176 | return; | |
177 | hrtimer_start(&base->timer, next->expires, HRTIMER_MODE_ABS); | |
178 | } | |
179 | } | |
180 | ||
7068b7a1 | 181 | |
180bf812 | 182 | /** |
7068b7a1 JS |
183 | * alarmtimer_fired - Handles alarm hrtimer being fired. |
184 | * @timer: pointer to hrtimer being run | |
ff3ead96 | 185 | * |
180bf812 JS |
186 | * When a alarm timer fires, this runs through the timerqueue to |
187 | * see which alarms expired, and runs those. If there are more alarm | |
188 | * timers queued for the future, we set the hrtimer to fire when | |
189 | * when the next future alarm timer expires. | |
ff3ead96 | 190 | */ |
7068b7a1 | 191 | static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) |
ff3ead96 | 192 | { |
7068b7a1 | 193 | struct alarm_base *base = container_of(timer, struct alarm_base, timer); |
ff3ead96 JS |
194 | struct timerqueue_node *next; |
195 | unsigned long flags; | |
196 | ktime_t now; | |
7068b7a1 | 197 | int ret = HRTIMER_NORESTART; |
54da23b7 | 198 | int restart = ALARMTIMER_NORESTART; |
ff3ead96 JS |
199 | |
200 | spin_lock_irqsave(&base->lock, flags); | |
201 | now = base->gettime(); | |
202 | while ((next = timerqueue_getnext(&base->timerqueue))) { | |
203 | struct alarm *alarm; | |
204 | ktime_t expired = next->expires; | |
205 | ||
c9c024b3 | 206 | if (expired.tv64 > now.tv64) |
ff3ead96 JS |
207 | break; |
208 | ||
209 | alarm = container_of(next, struct alarm, node); | |
210 | ||
211 | timerqueue_del(&base->timerqueue, &alarm->node); | |
a28cde81 | 212 | alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; |
54da23b7 | 213 | |
a28cde81 | 214 | alarm->state |= ALARMTIMER_STATE_CALLBACK; |
ff3ead96 JS |
215 | spin_unlock_irqrestore(&base->lock, flags); |
216 | if (alarm->function) | |
54da23b7 | 217 | restart = alarm->function(alarm, now); |
ff3ead96 | 218 | spin_lock_irqsave(&base->lock, flags); |
a28cde81 | 219 | alarm->state &= ~ALARMTIMER_STATE_CALLBACK; |
54da23b7 JS |
220 | |
221 | if (restart != ALARMTIMER_NORESTART) { | |
222 | timerqueue_add(&base->timerqueue, &alarm->node); | |
a28cde81 | 223 | alarm->state |= ALARMTIMER_STATE_ENQUEUED; |
54da23b7 | 224 | } |
ff3ead96 JS |
225 | } |
226 | ||
227 | if (next) { | |
7068b7a1 JS |
228 | hrtimer_set_expires(&base->timer, next->expires); |
229 | ret = HRTIMER_RESTART; | |
ff3ead96 JS |
230 | } |
231 | spin_unlock_irqrestore(&base->lock, flags); | |
ff3ead96 | 232 | |
7068b7a1 | 233 | return ret; |
ff3ead96 | 234 | |
ff3ead96 JS |
235 | } |
236 | ||
472647dc | 237 | #ifdef CONFIG_RTC_CLASS |
180bf812 | 238 | /** |
ff3ead96 JS |
239 | * alarmtimer_suspend - Suspend time callback |
240 | * @dev: unused | |
241 | * @state: unused | |
242 | * | |
243 | * When we are going into suspend, we look through the bases | |
244 | * to see which is the soonest timer to expire. We then | |
245 | * set an rtc timer to fire that far into the future, which | |
246 | * will wake us from suspend. | |
247 | */ | |
248 | static int alarmtimer_suspend(struct device *dev) | |
249 | { | |
250 | struct rtc_time tm; | |
251 | ktime_t min, now; | |
252 | unsigned long flags; | |
c008ba58 | 253 | struct rtc_device *rtc; |
ff3ead96 | 254 | int i; |
59a93c27 | 255 | int ret; |
ff3ead96 JS |
256 | |
257 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
258 | min = freezer_delta; | |
259 | freezer_delta = ktime_set(0, 0); | |
260 | spin_unlock_irqrestore(&freezer_delta_lock, flags); | |
261 | ||
8bc0dafb | 262 | rtc = alarmtimer_get_rtcdev(); |
ff3ead96 | 263 | /* If we have no rtcdev, just return */ |
c008ba58 | 264 | if (!rtc) |
ff3ead96 JS |
265 | return 0; |
266 | ||
267 | /* Find the soonest timer to expire*/ | |
268 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
269 | struct alarm_base *base = &alarm_bases[i]; | |
270 | struct timerqueue_node *next; | |
271 | ktime_t delta; | |
272 | ||
273 | spin_lock_irqsave(&base->lock, flags); | |
274 | next = timerqueue_getnext(&base->timerqueue); | |
275 | spin_unlock_irqrestore(&base->lock, flags); | |
276 | if (!next) | |
277 | continue; | |
278 | delta = ktime_sub(next->expires, base->gettime()); | |
279 | if (!min.tv64 || (delta.tv64 < min.tv64)) | |
280 | min = delta; | |
281 | } | |
282 | if (min.tv64 == 0) | |
283 | return 0; | |
284 | ||
59a93c27 TP |
285 | if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { |
286 | __pm_wakeup_event(ws, 2 * MSEC_PER_SEC); | |
287 | return -EBUSY; | |
288 | } | |
ff3ead96 JS |
289 | |
290 | /* Setup an rtc timer to fire that far in the future */ | |
c008ba58 JS |
291 | rtc_timer_cancel(rtc, &rtctimer); |
292 | rtc_read_time(rtc, &tm); | |
ff3ead96 JS |
293 | now = rtc_tm_to_ktime(tm); |
294 | now = ktime_add(now, min); | |
295 | ||
59a93c27 TP |
296 | /* Set alarm, if in the past reject suspend briefly to handle */ |
297 | ret = rtc_timer_start(rtc, &rtctimer, now, ktime_set(0, 0)); | |
298 | if (ret < 0) | |
299 | __pm_wakeup_event(ws, MSEC_PER_SEC); | |
300 | return ret; | |
ff3ead96 | 301 | } |
472647dc JS |
302 | #else |
303 | static int alarmtimer_suspend(struct device *dev) | |
304 | { | |
305 | return 0; | |
306 | } | |
307 | #endif | |
ff3ead96 | 308 | |
9a7adcf5 JS |
309 | static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) |
310 | { | |
311 | ktime_t delta; | |
312 | unsigned long flags; | |
313 | struct alarm_base *base = &alarm_bases[type]; | |
314 | ||
315 | delta = ktime_sub(absexp, base->gettime()); | |
316 | ||
317 | spin_lock_irqsave(&freezer_delta_lock, flags); | |
318 | if (!freezer_delta.tv64 || (delta.tv64 < freezer_delta.tv64)) | |
319 | freezer_delta = delta; | |
320 | spin_unlock_irqrestore(&freezer_delta_lock, flags); | |
321 | } | |
322 | ||
323 | ||
180bf812 | 324 | /** |
ff3ead96 JS |
325 | * alarm_init - Initialize an alarm structure |
326 | * @alarm: ptr to alarm to be initialized | |
327 | * @type: the type of the alarm | |
328 | * @function: callback that is run when the alarm fires | |
ff3ead96 JS |
329 | */ |
330 | void alarm_init(struct alarm *alarm, enum alarmtimer_type type, | |
4b41308d | 331 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) |
ff3ead96 JS |
332 | { |
333 | timerqueue_init(&alarm->node); | |
ff3ead96 JS |
334 | alarm->function = function; |
335 | alarm->type = type; | |
a28cde81 | 336 | alarm->state = ALARMTIMER_STATE_INACTIVE; |
ff3ead96 JS |
337 | } |
338 | ||
180bf812 | 339 | /** |
ff3ead96 JS |
340 | * alarm_start - Sets an alarm to fire |
341 | * @alarm: ptr to alarm to set | |
342 | * @start: time to run the alarm | |
ff3ead96 | 343 | */ |
9e264762 | 344 | void alarm_start(struct alarm *alarm, ktime_t start) |
ff3ead96 JS |
345 | { |
346 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
347 | unsigned long flags; | |
348 | ||
349 | spin_lock_irqsave(&base->lock, flags); | |
a28cde81 | 350 | if (alarmtimer_active(alarm)) |
ff3ead96 JS |
351 | alarmtimer_remove(base, alarm); |
352 | alarm->node.expires = start; | |
ff3ead96 | 353 | alarmtimer_enqueue(base, alarm); |
ff3ead96 JS |
354 | spin_unlock_irqrestore(&base->lock, flags); |
355 | } | |
356 | ||
180bf812 | 357 | /** |
9082c465 | 358 | * alarm_try_to_cancel - Tries to cancel an alarm timer |
ff3ead96 | 359 | * @alarm: ptr to alarm to be canceled |
9082c465 JS |
360 | * |
361 | * Returns 1 if the timer was canceled, 0 if it was not running, | |
362 | * and -1 if the callback was running | |
ff3ead96 | 363 | */ |
9082c465 | 364 | int alarm_try_to_cancel(struct alarm *alarm) |
ff3ead96 JS |
365 | { |
366 | struct alarm_base *base = &alarm_bases[alarm->type]; | |
367 | unsigned long flags; | |
9082c465 | 368 | int ret = -1; |
ff3ead96 | 369 | spin_lock_irqsave(&base->lock, flags); |
9082c465 JS |
370 | |
371 | if (alarmtimer_callback_running(alarm)) | |
372 | goto out; | |
373 | ||
374 | if (alarmtimer_is_queued(alarm)) { | |
ff3ead96 | 375 | alarmtimer_remove(base, alarm); |
9082c465 JS |
376 | ret = 1; |
377 | } else | |
378 | ret = 0; | |
379 | out: | |
ff3ead96 | 380 | spin_unlock_irqrestore(&base->lock, flags); |
9082c465 | 381 | return ret; |
ff3ead96 JS |
382 | } |
383 | ||
384 | ||
9082c465 JS |
385 | /** |
386 | * alarm_cancel - Spins trying to cancel an alarm timer until it is done | |
387 | * @alarm: ptr to alarm to be canceled | |
388 | * | |
389 | * Returns 1 if the timer was canceled, 0 if it was not active. | |
390 | */ | |
391 | int alarm_cancel(struct alarm *alarm) | |
392 | { | |
393 | for (;;) { | |
394 | int ret = alarm_try_to_cancel(alarm); | |
395 | if (ret >= 0) | |
396 | return ret; | |
397 | cpu_relax(); | |
398 | } | |
399 | } | |
400 | ||
dce75a8c JS |
401 | |
402 | u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) | |
403 | { | |
404 | u64 overrun = 1; | |
405 | ktime_t delta; | |
406 | ||
407 | delta = ktime_sub(now, alarm->node.expires); | |
408 | ||
409 | if (delta.tv64 < 0) | |
410 | return 0; | |
411 | ||
412 | if (unlikely(delta.tv64 >= interval.tv64)) { | |
413 | s64 incr = ktime_to_ns(interval); | |
414 | ||
415 | overrun = ktime_divns(delta, incr); | |
416 | ||
417 | alarm->node.expires = ktime_add_ns(alarm->node.expires, | |
418 | incr*overrun); | |
419 | ||
420 | if (alarm->node.expires.tv64 > now.tv64) | |
421 | return overrun; | |
422 | /* | |
423 | * This (and the ktime_add() below) is the | |
424 | * correction for exact: | |
425 | */ | |
426 | overrun++; | |
427 | } | |
428 | ||
429 | alarm->node.expires = ktime_add(alarm->node.expires, interval); | |
430 | return overrun; | |
431 | } | |
432 | ||
433 | ||
434 | ||
435 | ||
180bf812 | 436 | /** |
9a7adcf5 JS |
437 | * clock2alarm - helper that converts from clockid to alarmtypes |
438 | * @clockid: clockid. | |
9a7adcf5 JS |
439 | */ |
440 | static enum alarmtimer_type clock2alarm(clockid_t clockid) | |
441 | { | |
442 | if (clockid == CLOCK_REALTIME_ALARM) | |
443 | return ALARM_REALTIME; | |
444 | if (clockid == CLOCK_BOOTTIME_ALARM) | |
445 | return ALARM_BOOTTIME; | |
446 | return -1; | |
447 | } | |
448 | ||
180bf812 | 449 | /** |
9a7adcf5 JS |
450 | * alarm_handle_timer - Callback for posix timers |
451 | * @alarm: alarm that fired | |
452 | * | |
453 | * Posix timer callback for expired alarm timers. | |
454 | */ | |
4b41308d JS |
455 | static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm, |
456 | ktime_t now) | |
9a7adcf5 JS |
457 | { |
458 | struct k_itimer *ptr = container_of(alarm, struct k_itimer, | |
9e264762 | 459 | it.alarm.alarmtimer); |
9a7adcf5 JS |
460 | if (posix_timer_event(ptr, 0) != 0) |
461 | ptr->it_overrun++; | |
4b41308d | 462 | |
54da23b7 | 463 | /* Re-add periodic timers */ |
9e264762 JS |
464 | if (ptr->it.alarm.interval.tv64) { |
465 | ptr->it_overrun += alarm_forward(alarm, now, | |
466 | ptr->it.alarm.interval); | |
54da23b7 JS |
467 | return ALARMTIMER_RESTART; |
468 | } | |
4b41308d | 469 | return ALARMTIMER_NORESTART; |
9a7adcf5 JS |
470 | } |
471 | ||
180bf812 | 472 | /** |
9a7adcf5 JS |
473 | * alarm_clock_getres - posix getres interface |
474 | * @which_clock: clockid | |
475 | * @tp: timespec to fill | |
476 | * | |
477 | * Returns the granularity of underlying alarm base clock | |
478 | */ | |
479 | static int alarm_clock_getres(const clockid_t which_clock, struct timespec *tp) | |
480 | { | |
481 | clockid_t baseid = alarm_bases[clock2alarm(which_clock)].base_clockid; | |
482 | ||
1c6b39ad JS |
483 | if (!alarmtimer_get_rtcdev()) |
484 | return -ENOTSUPP; | |
485 | ||
9a7adcf5 JS |
486 | return hrtimer_get_res(baseid, tp); |
487 | } | |
488 | ||
489 | /** | |
490 | * alarm_clock_get - posix clock_get interface | |
491 | * @which_clock: clockid | |
492 | * @tp: timespec to fill. | |
493 | * | |
494 | * Provides the underlying alarm base time. | |
495 | */ | |
496 | static int alarm_clock_get(clockid_t which_clock, struct timespec *tp) | |
497 | { | |
498 | struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; | |
499 | ||
1c6b39ad JS |
500 | if (!alarmtimer_get_rtcdev()) |
501 | return -ENOTSUPP; | |
502 | ||
9a7adcf5 JS |
503 | *tp = ktime_to_timespec(base->gettime()); |
504 | return 0; | |
505 | } | |
506 | ||
507 | /** | |
508 | * alarm_timer_create - posix timer_create interface | |
509 | * @new_timer: k_itimer pointer to manage | |
510 | * | |
511 | * Initializes the k_itimer structure. | |
512 | */ | |
513 | static int alarm_timer_create(struct k_itimer *new_timer) | |
514 | { | |
515 | enum alarmtimer_type type; | |
516 | struct alarm_base *base; | |
517 | ||
1c6b39ad JS |
518 | if (!alarmtimer_get_rtcdev()) |
519 | return -ENOTSUPP; | |
520 | ||
9a7adcf5 JS |
521 | if (!capable(CAP_WAKE_ALARM)) |
522 | return -EPERM; | |
523 | ||
524 | type = clock2alarm(new_timer->it_clock); | |
525 | base = &alarm_bases[type]; | |
9e264762 | 526 | alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer); |
9a7adcf5 JS |
527 | return 0; |
528 | } | |
529 | ||
530 | /** | |
531 | * alarm_timer_get - posix timer_get interface | |
532 | * @new_timer: k_itimer pointer | |
533 | * @cur_setting: itimerspec data to fill | |
534 | * | |
535 | * Copies the itimerspec data out from the k_itimer | |
536 | */ | |
537 | static void alarm_timer_get(struct k_itimer *timr, | |
538 | struct itimerspec *cur_setting) | |
539 | { | |
ea7802f6 JS |
540 | memset(cur_setting, 0, sizeof(struct itimerspec)); |
541 | ||
9a7adcf5 | 542 | cur_setting->it_interval = |
9e264762 | 543 | ktime_to_timespec(timr->it.alarm.interval); |
9a7adcf5 | 544 | cur_setting->it_value = |
9e264762 | 545 | ktime_to_timespec(timr->it.alarm.alarmtimer.node.expires); |
9a7adcf5 JS |
546 | return; |
547 | } | |
548 | ||
549 | /** | |
550 | * alarm_timer_del - posix timer_del interface | |
551 | * @timr: k_itimer pointer to be deleted | |
552 | * | |
553 | * Cancels any programmed alarms for the given timer. | |
554 | */ | |
555 | static int alarm_timer_del(struct k_itimer *timr) | |
556 | { | |
1c6b39ad JS |
557 | if (!rtcdev) |
558 | return -ENOTSUPP; | |
559 | ||
9082c465 JS |
560 | if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0) |
561 | return TIMER_RETRY; | |
562 | ||
9a7adcf5 JS |
563 | return 0; |
564 | } | |
565 | ||
566 | /** | |
567 | * alarm_timer_set - posix timer_set interface | |
568 | * @timr: k_itimer pointer to be deleted | |
569 | * @flags: timer flags | |
570 | * @new_setting: itimerspec to be used | |
571 | * @old_setting: itimerspec being replaced | |
572 | * | |
573 | * Sets the timer to new_setting, and starts the timer. | |
574 | */ | |
575 | static int alarm_timer_set(struct k_itimer *timr, int flags, | |
576 | struct itimerspec *new_setting, | |
577 | struct itimerspec *old_setting) | |
578 | { | |
1c6b39ad JS |
579 | if (!rtcdev) |
580 | return -ENOTSUPP; | |
581 | ||
971c90bf JS |
582 | if (old_setting) |
583 | alarm_timer_get(timr, old_setting); | |
9a7adcf5 JS |
584 | |
585 | /* If the timer was already set, cancel it */ | |
9082c465 JS |
586 | if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0) |
587 | return TIMER_RETRY; | |
9a7adcf5 JS |
588 | |
589 | /* start the timer */ | |
9e264762 JS |
590 | timr->it.alarm.interval = timespec_to_ktime(new_setting->it_interval); |
591 | alarm_start(&timr->it.alarm.alarmtimer, | |
592 | timespec_to_ktime(new_setting->it_value)); | |
9a7adcf5 JS |
593 | return 0; |
594 | } | |
595 | ||
596 | /** | |
597 | * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep | |
598 | * @alarm: ptr to alarm that fired | |
599 | * | |
600 | * Wakes up the task that set the alarmtimer | |
601 | */ | |
4b41308d JS |
602 | static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm, |
603 | ktime_t now) | |
9a7adcf5 JS |
604 | { |
605 | struct task_struct *task = (struct task_struct *)alarm->data; | |
606 | ||
607 | alarm->data = NULL; | |
608 | if (task) | |
609 | wake_up_process(task); | |
4b41308d | 610 | return ALARMTIMER_NORESTART; |
9a7adcf5 JS |
611 | } |
612 | ||
613 | /** | |
614 | * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation | |
615 | * @alarm: ptr to alarmtimer | |
616 | * @absexp: absolute expiration time | |
617 | * | |
618 | * Sets the alarm timer and sleeps until it is fired or interrupted. | |
619 | */ | |
620 | static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp) | |
621 | { | |
622 | alarm->data = (void *)current; | |
623 | do { | |
624 | set_current_state(TASK_INTERRUPTIBLE); | |
9e264762 | 625 | alarm_start(alarm, absexp); |
9a7adcf5 JS |
626 | if (likely(alarm->data)) |
627 | schedule(); | |
628 | ||
629 | alarm_cancel(alarm); | |
630 | } while (alarm->data && !signal_pending(current)); | |
631 | ||
632 | __set_current_state(TASK_RUNNING); | |
633 | ||
634 | return (alarm->data == NULL); | |
635 | } | |
636 | ||
637 | ||
638 | /** | |
639 | * update_rmtp - Update remaining timespec value | |
640 | * @exp: expiration time | |
641 | * @type: timer type | |
642 | * @rmtp: user pointer to remaining timepsec value | |
643 | * | |
644 | * Helper function that fills in rmtp value with time between | |
645 | * now and the exp value | |
646 | */ | |
647 | static int update_rmtp(ktime_t exp, enum alarmtimer_type type, | |
648 | struct timespec __user *rmtp) | |
649 | { | |
650 | struct timespec rmt; | |
651 | ktime_t rem; | |
652 | ||
653 | rem = ktime_sub(exp, alarm_bases[type].gettime()); | |
654 | ||
655 | if (rem.tv64 <= 0) | |
656 | return 0; | |
657 | rmt = ktime_to_timespec(rem); | |
658 | ||
659 | if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) | |
660 | return -EFAULT; | |
661 | ||
662 | return 1; | |
663 | ||
664 | } | |
665 | ||
666 | /** | |
667 | * alarm_timer_nsleep_restart - restartblock alarmtimer nsleep | |
668 | * @restart: ptr to restart block | |
669 | * | |
670 | * Handles restarted clock_nanosleep calls | |
671 | */ | |
672 | static long __sched alarm_timer_nsleep_restart(struct restart_block *restart) | |
673 | { | |
ab8177bc | 674 | enum alarmtimer_type type = restart->nanosleep.clockid; |
9a7adcf5 JS |
675 | ktime_t exp; |
676 | struct timespec __user *rmtp; | |
677 | struct alarm alarm; | |
678 | int ret = 0; | |
679 | ||
680 | exp.tv64 = restart->nanosleep.expires; | |
681 | alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); | |
682 | ||
683 | if (alarmtimer_do_nsleep(&alarm, exp)) | |
684 | goto out; | |
685 | ||
686 | if (freezing(current)) | |
687 | alarmtimer_freezerset(exp, type); | |
688 | ||
689 | rmtp = restart->nanosleep.rmtp; | |
690 | if (rmtp) { | |
691 | ret = update_rmtp(exp, type, rmtp); | |
692 | if (ret <= 0) | |
693 | goto out; | |
694 | } | |
695 | ||
696 | ||
697 | /* The other values in restart are already filled in */ | |
698 | ret = -ERESTART_RESTARTBLOCK; | |
699 | out: | |
700 | return ret; | |
701 | } | |
702 | ||
703 | /** | |
704 | * alarm_timer_nsleep - alarmtimer nanosleep | |
705 | * @which_clock: clockid | |
706 | * @flags: determins abstime or relative | |
707 | * @tsreq: requested sleep time (abs or rel) | |
708 | * @rmtp: remaining sleep time saved | |
709 | * | |
710 | * Handles clock_nanosleep calls against _ALARM clockids | |
711 | */ | |
712 | static int alarm_timer_nsleep(const clockid_t which_clock, int flags, | |
713 | struct timespec *tsreq, struct timespec __user *rmtp) | |
714 | { | |
715 | enum alarmtimer_type type = clock2alarm(which_clock); | |
716 | struct alarm alarm; | |
717 | ktime_t exp; | |
718 | int ret = 0; | |
719 | struct restart_block *restart; | |
720 | ||
1c6b39ad JS |
721 | if (!alarmtimer_get_rtcdev()) |
722 | return -ENOTSUPP; | |
723 | ||
9a7adcf5 JS |
724 | if (!capable(CAP_WAKE_ALARM)) |
725 | return -EPERM; | |
726 | ||
727 | alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); | |
728 | ||
729 | exp = timespec_to_ktime(*tsreq); | |
730 | /* Convert (if necessary) to absolute time */ | |
731 | if (flags != TIMER_ABSTIME) { | |
732 | ktime_t now = alarm_bases[type].gettime(); | |
733 | exp = ktime_add(now, exp); | |
734 | } | |
735 | ||
736 | if (alarmtimer_do_nsleep(&alarm, exp)) | |
737 | goto out; | |
738 | ||
739 | if (freezing(current)) | |
740 | alarmtimer_freezerset(exp, type); | |
741 | ||
742 | /* abs timers don't set remaining time or restart */ | |
743 | if (flags == TIMER_ABSTIME) { | |
744 | ret = -ERESTARTNOHAND; | |
745 | goto out; | |
746 | } | |
747 | ||
748 | if (rmtp) { | |
749 | ret = update_rmtp(exp, type, rmtp); | |
750 | if (ret <= 0) | |
751 | goto out; | |
752 | } | |
753 | ||
754 | restart = ¤t_thread_info()->restart_block; | |
755 | restart->fn = alarm_timer_nsleep_restart; | |
ab8177bc | 756 | restart->nanosleep.clockid = type; |
9a7adcf5 JS |
757 | restart->nanosleep.expires = exp.tv64; |
758 | restart->nanosleep.rmtp = rmtp; | |
759 | ret = -ERESTART_RESTARTBLOCK; | |
760 | ||
761 | out: | |
762 | return ret; | |
763 | } | |
ff3ead96 | 764 | |
ff3ead96 JS |
765 | |
766 | /* Suspend hook structures */ | |
767 | static const struct dev_pm_ops alarmtimer_pm_ops = { | |
768 | .suspend = alarmtimer_suspend, | |
769 | }; | |
770 | ||
771 | static struct platform_driver alarmtimer_driver = { | |
772 | .driver = { | |
773 | .name = "alarmtimer", | |
774 | .pm = &alarmtimer_pm_ops, | |
775 | } | |
776 | }; | |
777 | ||
778 | /** | |
779 | * alarmtimer_init - Initialize alarm timer code | |
780 | * | |
781 | * This function initializes the alarm bases and registers | |
782 | * the posix clock ids. | |
783 | */ | |
784 | static int __init alarmtimer_init(void) | |
785 | { | |
4523f6ad | 786 | struct platform_device *pdev; |
ff3ead96 JS |
787 | int error = 0; |
788 | int i; | |
9a7adcf5 JS |
789 | struct k_clock alarm_clock = { |
790 | .clock_getres = alarm_clock_getres, | |
791 | .clock_get = alarm_clock_get, | |
792 | .timer_create = alarm_timer_create, | |
793 | .timer_set = alarm_timer_set, | |
794 | .timer_del = alarm_timer_del, | |
795 | .timer_get = alarm_timer_get, | |
796 | .nsleep = alarm_timer_nsleep, | |
797 | }; | |
798 | ||
c5e14e76 | 799 | alarmtimer_rtc_timer_init(); |
ad30dfa9 | 800 | |
9a7adcf5 JS |
801 | posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock); |
802 | posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock); | |
ff3ead96 JS |
803 | |
804 | /* Initialize alarm bases */ | |
805 | alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; | |
806 | alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real; | |
807 | alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; | |
808 | alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime; | |
809 | for (i = 0; i < ALARM_NUMTYPE; i++) { | |
810 | timerqueue_init_head(&alarm_bases[i].timerqueue); | |
811 | spin_lock_init(&alarm_bases[i].lock); | |
812 | hrtimer_init(&alarm_bases[i].timer, | |
813 | alarm_bases[i].base_clockid, | |
814 | HRTIMER_MODE_ABS); | |
815 | alarm_bases[i].timer.function = alarmtimer_fired; | |
ff3ead96 | 816 | } |
8bc0dafb | 817 | |
4523f6ad TG |
818 | error = alarmtimer_rtc_interface_setup(); |
819 | if (error) | |
820 | return error; | |
821 | ||
ff3ead96 | 822 | error = platform_driver_register(&alarmtimer_driver); |
4523f6ad TG |
823 | if (error) |
824 | goto out_if; | |
ff3ead96 | 825 | |
4523f6ad TG |
826 | pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0); |
827 | if (IS_ERR(pdev)) { | |
828 | error = PTR_ERR(pdev); | |
829 | goto out_drv; | |
830 | } | |
59a93c27 | 831 | ws = wakeup_source_register("alarmtimer"); |
4523f6ad TG |
832 | return 0; |
833 | ||
834 | out_drv: | |
835 | platform_driver_unregister(&alarmtimer_driver); | |
836 | out_if: | |
837 | alarmtimer_rtc_interface_remove(); | |
ff3ead96 JS |
838 | return error; |
839 | } | |
840 | device_initcall(alarmtimer_init); |