John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 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 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 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 |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 33 | * @gettime: Function to read the time correlating to the base |
| 34 | * @base_clockid: clockid for the base |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 35 | */ |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 36 | static struct alarm_base { |
| 37 | spinlock_t lock; |
| 38 | struct timerqueue_head timerqueue; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 39 | ktime_t (*gettime)(void); |
| 40 | clockid_t base_clockid; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 41 | } alarm_bases[ALARM_NUMTYPE]; |
| 42 | |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 43 | /* freezer delta & lock used to handle clock_nanosleep triggered wakeups */ |
| 44 | static ktime_t freezer_delta; |
| 45 | static DEFINE_SPINLOCK(freezer_delta_lock); |
| 46 | |
Todd Poynor | 59a93c2 | 2012-08-09 00:37:27 -0700 | [diff] [blame] | 47 | static struct wakeup_source *ws; |
| 48 | |
John Stultz | 472647d | 2011-04-29 15:03:10 -0700 | [diff] [blame] | 49 | #ifdef CONFIG_RTC_CLASS |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 50 | /* rtc timer and device for setting alarm wakeups at suspend */ |
Thomas Gleixner | c5e14e7 | 2012-03-24 12:46:23 +0100 | [diff] [blame] | 51 | static struct rtc_timer rtctimer; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 52 | static struct rtc_device *rtcdev; |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 53 | static DEFINE_SPINLOCK(rtcdev_lock); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 54 | |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 55 | /** |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 56 | * alarmtimer_get_rtcdev - Return selected rtcdevice |
| 57 | * |
| 58 | * This function returns the rtc device to use for wakealarms. |
| 59 | * If one has not already been chosen, it checks to see if a |
| 60 | * functional rtc device is available. |
| 61 | */ |
John Stultz | 57c498f | 2012-04-20 12:31:45 -0700 | [diff] [blame] | 62 | struct rtc_device *alarmtimer_get_rtcdev(void) |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 63 | { |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 64 | unsigned long flags; |
| 65 | struct rtc_device *ret; |
| 66 | |
| 67 | spin_lock_irqsave(&rtcdev_lock, flags); |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 68 | ret = rtcdev; |
| 69 | spin_unlock_irqrestore(&rtcdev_lock, flags); |
| 70 | |
| 71 | return ret; |
| 72 | } |
Pramod Gurav | 71d5d2b | 2014-06-13 11:49:42 +0530 | [diff] [blame] | 73 | EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); |
John Stultz | 8bc0daf | 2011-07-14 18:35:13 -0700 | [diff] [blame] | 74 | |
| 75 | static int alarmtimer_rtc_add_device(struct device *dev, |
| 76 | struct class_interface *class_intf) |
| 77 | { |
| 78 | unsigned long flags; |
| 79 | struct rtc_device *rtc = to_rtc_device(dev); |
| 80 | |
| 81 | if (rtcdev) |
| 82 | return -EBUSY; |
| 83 | |
| 84 | if (!rtc->ops->set_alarm) |
| 85 | return -1; |
| 86 | if (!device_may_wakeup(rtc->dev.parent)) |
| 87 | return -1; |
| 88 | |
| 89 | spin_lock_irqsave(&rtcdev_lock, flags); |
| 90 | if (!rtcdev) { |
| 91 | rtcdev = rtc; |
| 92 | /* hold a reference so it doesn't go away */ |
| 93 | get_device(dev); |
| 94 | } |
| 95 | spin_unlock_irqrestore(&rtcdev_lock, flags); |
| 96 | return 0; |
| 97 | } |
| 98 | |
Thomas Gleixner | c5e14e7 | 2012-03-24 12:46:23 +0100 | [diff] [blame] | 99 | static inline void alarmtimer_rtc_timer_init(void) |
| 100 | { |
| 101 | rtc_timer_init(&rtctimer, NULL, NULL); |
| 102 | } |
| 103 | |
John Stultz | 8bc0daf | 2011-07-14 18:35:13 -0700 | [diff] [blame] | 104 | static struct class_interface alarmtimer_rtc_interface = { |
| 105 | .add_dev = &alarmtimer_rtc_add_device, |
| 106 | }; |
| 107 | |
Thomas Gleixner | 4523f6a | 2011-09-14 10:54:29 +0200 | [diff] [blame] | 108 | static int alarmtimer_rtc_interface_setup(void) |
John Stultz | 8bc0daf | 2011-07-14 18:35:13 -0700 | [diff] [blame] | 109 | { |
| 110 | alarmtimer_rtc_interface.class = rtc_class; |
Thomas Gleixner | 4523f6a | 2011-09-14 10:54:29 +0200 | [diff] [blame] | 111 | return class_interface_register(&alarmtimer_rtc_interface); |
| 112 | } |
| 113 | static void alarmtimer_rtc_interface_remove(void) |
| 114 | { |
| 115 | class_interface_unregister(&alarmtimer_rtc_interface); |
John Stultz | 8bc0daf | 2011-07-14 18:35:13 -0700 | [diff] [blame] | 116 | } |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 117 | #else |
John Stultz | 57c498f | 2012-04-20 12:31:45 -0700 | [diff] [blame] | 118 | struct rtc_device *alarmtimer_get_rtcdev(void) |
Thomas Gleixner | 4523f6a | 2011-09-14 10:54:29 +0200 | [diff] [blame] | 119 | { |
| 120 | return NULL; |
| 121 | } |
| 122 | #define rtcdev (NULL) |
| 123 | static inline int alarmtimer_rtc_interface_setup(void) { return 0; } |
| 124 | static inline void alarmtimer_rtc_interface_remove(void) { } |
Thomas Gleixner | c5e14e7 | 2012-03-24 12:46:23 +0100 | [diff] [blame] | 125 | static inline void alarmtimer_rtc_timer_init(void) { } |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 126 | #endif |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 127 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 128 | /** |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 129 | * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue |
| 130 | * @base: pointer to the base where the timer is being run |
| 131 | * @alarm: pointer to alarm being enqueued. |
| 132 | * |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 133 | * Adds alarm to a alarm_base timerqueue |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 134 | * |
| 135 | * Must hold base->lock when calling. |
| 136 | */ |
| 137 | static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) |
| 138 | { |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 139 | if (alarm->state & ALARMTIMER_STATE_ENQUEUED) |
| 140 | timerqueue_del(&base->timerqueue, &alarm->node); |
| 141 | |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 142 | timerqueue_add(&base->timerqueue, &alarm->node); |
John Stultz | a28cde8 | 2011-08-10 12:30:21 -0700 | [diff] [blame] | 143 | alarm->state |= ALARMTIMER_STATE_ENQUEUED; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 144 | } |
| 145 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 146 | /** |
John Stultz | a65bcc1 | 2012-09-13 19:25:22 -0400 | [diff] [blame] | 147 | * alarmtimer_dequeue - Removes an alarm timer from an alarm_base timerqueue |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 148 | * @base: pointer to the base where the timer is running |
| 149 | * @alarm: pointer to alarm being removed |
| 150 | * |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 151 | * Removes alarm to a alarm_base timerqueue |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 152 | * |
| 153 | * Must hold base->lock when calling. |
| 154 | */ |
John Stultz | a65bcc1 | 2012-09-13 19:25:22 -0400 | [diff] [blame] | 155 | static void alarmtimer_dequeue(struct alarm_base *base, struct alarm *alarm) |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 156 | { |
John Stultz | a28cde8 | 2011-08-10 12:30:21 -0700 | [diff] [blame] | 157 | if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) |
| 158 | return; |
| 159 | |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 160 | timerqueue_del(&base->timerqueue, &alarm->node); |
John Stultz | a28cde8 | 2011-08-10 12:30:21 -0700 | [diff] [blame] | 161 | alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 162 | } |
| 163 | |
John Stultz | 7068b7a | 2011-04-28 13:29:18 -0700 | [diff] [blame] | 164 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 165 | /** |
John Stultz | 7068b7a | 2011-04-28 13:29:18 -0700 | [diff] [blame] | 166 | * alarmtimer_fired - Handles alarm hrtimer being fired. |
| 167 | * @timer: pointer to hrtimer being run |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 168 | * |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 169 | * When a alarm timer fires, this runs through the timerqueue to |
| 170 | * see which alarms expired, and runs those. If there are more alarm |
| 171 | * timers queued for the future, we set the hrtimer to fire when |
| 172 | * when the next future alarm timer expires. |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 173 | */ |
John Stultz | 7068b7a | 2011-04-28 13:29:18 -0700 | [diff] [blame] | 174 | static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 175 | { |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 176 | struct alarm *alarm = container_of(timer, struct alarm, timer); |
| 177 | struct alarm_base *base = &alarm_bases[alarm->type]; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 178 | unsigned long flags; |
John Stultz | 7068b7a | 2011-04-28 13:29:18 -0700 | [diff] [blame] | 179 | int ret = HRTIMER_NORESTART; |
John Stultz | 54da23b | 2011-08-10 11:08:07 -0700 | [diff] [blame] | 180 | int restart = ALARMTIMER_NORESTART; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 181 | |
| 182 | spin_lock_irqsave(&base->lock, flags); |
John Stultz | a65bcc1 | 2012-09-13 19:25:22 -0400 | [diff] [blame] | 183 | alarmtimer_dequeue(base, alarm); |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 184 | spin_unlock_irqrestore(&base->lock, flags); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 185 | |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 186 | if (alarm->function) |
| 187 | restart = alarm->function(alarm, base->gettime()); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 188 | |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 189 | spin_lock_irqsave(&base->lock, flags); |
| 190 | if (restart != ALARMTIMER_NORESTART) { |
| 191 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); |
| 192 | alarmtimer_enqueue(base, alarm); |
John Stultz | 7068b7a | 2011-04-28 13:29:18 -0700 | [diff] [blame] | 193 | ret = HRTIMER_RESTART; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 194 | } |
| 195 | spin_unlock_irqrestore(&base->lock, flags); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 196 | |
John Stultz | 7068b7a | 2011-04-28 13:29:18 -0700 | [diff] [blame] | 197 | return ret; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 198 | |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 199 | } |
| 200 | |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 201 | ktime_t alarm_expires_remaining(const struct alarm *alarm) |
| 202 | { |
| 203 | struct alarm_base *base = &alarm_bases[alarm->type]; |
| 204 | return ktime_sub(alarm->node.expires, base->gettime()); |
| 205 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 206 | EXPORT_SYMBOL_GPL(alarm_expires_remaining); |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 207 | |
John Stultz | 472647d | 2011-04-29 15:03:10 -0700 | [diff] [blame] | 208 | #ifdef CONFIG_RTC_CLASS |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 209 | /** |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 210 | * alarmtimer_suspend - Suspend time callback |
| 211 | * @dev: unused |
| 212 | * @state: unused |
| 213 | * |
| 214 | * When we are going into suspend, we look through the bases |
| 215 | * to see which is the soonest timer to expire. We then |
| 216 | * set an rtc timer to fire that far into the future, which |
| 217 | * will wake us from suspend. |
| 218 | */ |
| 219 | static int alarmtimer_suspend(struct device *dev) |
| 220 | { |
| 221 | struct rtc_time tm; |
| 222 | ktime_t min, now; |
| 223 | unsigned long flags; |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 224 | struct rtc_device *rtc; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 225 | int i; |
Todd Poynor | 59a93c2 | 2012-08-09 00:37:27 -0700 | [diff] [blame] | 226 | int ret; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 227 | |
| 228 | spin_lock_irqsave(&freezer_delta_lock, flags); |
| 229 | min = freezer_delta; |
| 230 | freezer_delta = ktime_set(0, 0); |
| 231 | spin_unlock_irqrestore(&freezer_delta_lock, flags); |
| 232 | |
John Stultz | 8bc0daf | 2011-07-14 18:35:13 -0700 | [diff] [blame] | 233 | rtc = alarmtimer_get_rtcdev(); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 234 | /* If we have no rtcdev, just return */ |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 235 | if (!rtc) |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 236 | return 0; |
| 237 | |
| 238 | /* Find the soonest timer to expire*/ |
| 239 | for (i = 0; i < ALARM_NUMTYPE; i++) { |
| 240 | struct alarm_base *base = &alarm_bases[i]; |
| 241 | struct timerqueue_node *next; |
| 242 | ktime_t delta; |
| 243 | |
| 244 | spin_lock_irqsave(&base->lock, flags); |
| 245 | next = timerqueue_getnext(&base->timerqueue); |
| 246 | spin_unlock_irqrestore(&base->lock, flags); |
| 247 | if (!next) |
| 248 | continue; |
| 249 | delta = ktime_sub(next->expires, base->gettime()); |
| 250 | if (!min.tv64 || (delta.tv64 < min.tv64)) |
| 251 | min = delta; |
| 252 | } |
| 253 | if (min.tv64 == 0) |
| 254 | return 0; |
| 255 | |
Todd Poynor | 59a93c2 | 2012-08-09 00:37:27 -0700 | [diff] [blame] | 256 | if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { |
| 257 | __pm_wakeup_event(ws, 2 * MSEC_PER_SEC); |
| 258 | return -EBUSY; |
| 259 | } |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 260 | |
| 261 | /* Setup an rtc timer to fire that far in the future */ |
John Stultz | c008ba58 | 2011-06-16 18:27:09 -0700 | [diff] [blame] | 262 | rtc_timer_cancel(rtc, &rtctimer); |
| 263 | rtc_read_time(rtc, &tm); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 264 | now = rtc_tm_to_ktime(tm); |
| 265 | now = ktime_add(now, min); |
| 266 | |
Todd Poynor | 59a93c2 | 2012-08-09 00:37:27 -0700 | [diff] [blame] | 267 | /* Set alarm, if in the past reject suspend briefly to handle */ |
| 268 | ret = rtc_timer_start(rtc, &rtctimer, now, ktime_set(0, 0)); |
| 269 | if (ret < 0) |
| 270 | __pm_wakeup_event(ws, MSEC_PER_SEC); |
| 271 | return ret; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 272 | } |
zhuo-hao | a0e3213 | 2015-11-17 20:08:07 +0800 | [diff] [blame] | 273 | |
| 274 | static int alarmtimer_resume(struct device *dev) |
| 275 | { |
| 276 | struct rtc_device *rtc; |
| 277 | |
| 278 | rtc = alarmtimer_get_rtcdev(); |
| 279 | if (rtc) |
| 280 | rtc_timer_cancel(rtc, &rtctimer); |
| 281 | return 0; |
| 282 | } |
| 283 | |
John Stultz | 472647d | 2011-04-29 15:03:10 -0700 | [diff] [blame] | 284 | #else |
| 285 | static int alarmtimer_suspend(struct device *dev) |
| 286 | { |
| 287 | return 0; |
| 288 | } |
zhuo-hao | a0e3213 | 2015-11-17 20:08:07 +0800 | [diff] [blame] | 289 | |
| 290 | static int alarmtimer_resume(struct device *dev) |
| 291 | { |
| 292 | return 0; |
| 293 | } |
John Stultz | 472647d | 2011-04-29 15:03:10 -0700 | [diff] [blame] | 294 | #endif |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 295 | |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 296 | static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) |
| 297 | { |
| 298 | ktime_t delta; |
| 299 | unsigned long flags; |
| 300 | struct alarm_base *base = &alarm_bases[type]; |
| 301 | |
| 302 | delta = ktime_sub(absexp, base->gettime()); |
| 303 | |
| 304 | spin_lock_irqsave(&freezer_delta_lock, flags); |
| 305 | if (!freezer_delta.tv64 || (delta.tv64 < freezer_delta.tv64)) |
| 306 | freezer_delta = delta; |
| 307 | spin_unlock_irqrestore(&freezer_delta_lock, flags); |
| 308 | } |
| 309 | |
| 310 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 311 | /** |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 312 | * alarm_init - Initialize an alarm structure |
| 313 | * @alarm: ptr to alarm to be initialized |
| 314 | * @type: the type of the alarm |
| 315 | * @function: callback that is run when the alarm fires |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 316 | */ |
| 317 | void alarm_init(struct alarm *alarm, enum alarmtimer_type type, |
John Stultz | 4b41308 | 2011-08-10 10:37:59 -0700 | [diff] [blame] | 318 | enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 319 | { |
| 320 | timerqueue_init(&alarm->node); |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 321 | hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid, |
| 322 | HRTIMER_MODE_ABS); |
| 323 | alarm->timer.function = alarmtimer_fired; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 324 | alarm->function = function; |
| 325 | alarm->type = type; |
John Stultz | a28cde8 | 2011-08-10 12:30:21 -0700 | [diff] [blame] | 326 | alarm->state = ALARMTIMER_STATE_INACTIVE; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 327 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 328 | EXPORT_SYMBOL_GPL(alarm_init); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 329 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 330 | /** |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 331 | * alarm_start - Sets an absolute alarm to fire |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 332 | * @alarm: ptr to alarm to set |
| 333 | * @start: time to run the alarm |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 334 | */ |
Thomas Gleixner | b193217 | 2015-04-14 21:09:18 +0000 | [diff] [blame] | 335 | void alarm_start(struct alarm *alarm, ktime_t start) |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 336 | { |
| 337 | struct alarm_base *base = &alarm_bases[alarm->type]; |
| 338 | unsigned long flags; |
| 339 | |
| 340 | spin_lock_irqsave(&base->lock, flags); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 341 | alarm->node.expires = start; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 342 | alarmtimer_enqueue(base, alarm); |
Thomas Gleixner | b193217 | 2015-04-14 21:09:18 +0000 | [diff] [blame] | 343 | hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 344 | spin_unlock_irqrestore(&base->lock, flags); |
| 345 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 346 | EXPORT_SYMBOL_GPL(alarm_start); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 347 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 348 | /** |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 349 | * alarm_start_relative - Sets a relative alarm to fire |
| 350 | * @alarm: ptr to alarm to set |
| 351 | * @start: time relative to now to run the alarm |
| 352 | */ |
Thomas Gleixner | b193217 | 2015-04-14 21:09:18 +0000 | [diff] [blame] | 353 | void alarm_start_relative(struct alarm *alarm, ktime_t start) |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 354 | { |
| 355 | struct alarm_base *base = &alarm_bases[alarm->type]; |
| 356 | |
Thomas Gleixner | 8ee7f06 | 2017-05-30 23:15:34 +0200 | [diff] [blame] | 357 | start = ktime_add_safe(start, base->gettime()); |
Thomas Gleixner | b193217 | 2015-04-14 21:09:18 +0000 | [diff] [blame] | 358 | alarm_start(alarm, start); |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 359 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 360 | EXPORT_SYMBOL_GPL(alarm_start_relative); |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 361 | |
| 362 | void alarm_restart(struct alarm *alarm) |
| 363 | { |
| 364 | struct alarm_base *base = &alarm_bases[alarm->type]; |
| 365 | unsigned long flags; |
| 366 | |
| 367 | spin_lock_irqsave(&base->lock, flags); |
| 368 | hrtimer_set_expires(&alarm->timer, alarm->node.expires); |
| 369 | hrtimer_restart(&alarm->timer); |
| 370 | alarmtimer_enqueue(base, alarm); |
| 371 | spin_unlock_irqrestore(&base->lock, flags); |
| 372 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 373 | EXPORT_SYMBOL_GPL(alarm_restart); |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 374 | |
| 375 | /** |
John Stultz | 9082c46 | 2011-08-10 12:41:36 -0700 | [diff] [blame] | 376 | * alarm_try_to_cancel - Tries to cancel an alarm timer |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 377 | * @alarm: ptr to alarm to be canceled |
John Stultz | 9082c46 | 2011-08-10 12:41:36 -0700 | [diff] [blame] | 378 | * |
| 379 | * Returns 1 if the timer was canceled, 0 if it was not running, |
| 380 | * and -1 if the callback was running |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 381 | */ |
John Stultz | 9082c46 | 2011-08-10 12:41:36 -0700 | [diff] [blame] | 382 | int alarm_try_to_cancel(struct alarm *alarm) |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 383 | { |
| 384 | struct alarm_base *base = &alarm_bases[alarm->type]; |
| 385 | unsigned long flags; |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 386 | int ret; |
| 387 | |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 388 | spin_lock_irqsave(&base->lock, flags); |
John Stultz | dae373b | 2012-09-13 19:12:16 -0400 | [diff] [blame] | 389 | ret = hrtimer_try_to_cancel(&alarm->timer); |
| 390 | if (ret >= 0) |
John Stultz | a65bcc1 | 2012-09-13 19:25:22 -0400 | [diff] [blame] | 391 | alarmtimer_dequeue(base, alarm); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 392 | spin_unlock_irqrestore(&base->lock, flags); |
John Stultz | 9082c46 | 2011-08-10 12:41:36 -0700 | [diff] [blame] | 393 | return ret; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 394 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 395 | EXPORT_SYMBOL_GPL(alarm_try_to_cancel); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 396 | |
| 397 | |
John Stultz | 9082c46 | 2011-08-10 12:41:36 -0700 | [diff] [blame] | 398 | /** |
| 399 | * alarm_cancel - Spins trying to cancel an alarm timer until it is done |
| 400 | * @alarm: ptr to alarm to be canceled |
| 401 | * |
| 402 | * Returns 1 if the timer was canceled, 0 if it was not active. |
| 403 | */ |
| 404 | int alarm_cancel(struct alarm *alarm) |
| 405 | { |
| 406 | for (;;) { |
| 407 | int ret = alarm_try_to_cancel(alarm); |
| 408 | if (ret >= 0) |
| 409 | return ret; |
| 410 | cpu_relax(); |
| 411 | } |
| 412 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 413 | EXPORT_SYMBOL_GPL(alarm_cancel); |
John Stultz | 9082c46 | 2011-08-10 12:41:36 -0700 | [diff] [blame] | 414 | |
John Stultz | dce75a8 | 2011-08-10 11:31:03 -0700 | [diff] [blame] | 415 | |
| 416 | u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) |
| 417 | { |
| 418 | u64 overrun = 1; |
| 419 | ktime_t delta; |
| 420 | |
| 421 | delta = ktime_sub(now, alarm->node.expires); |
| 422 | |
| 423 | if (delta.tv64 < 0) |
| 424 | return 0; |
| 425 | |
| 426 | if (unlikely(delta.tv64 >= interval.tv64)) { |
| 427 | s64 incr = ktime_to_ns(interval); |
| 428 | |
| 429 | overrun = ktime_divns(delta, incr); |
| 430 | |
| 431 | alarm->node.expires = ktime_add_ns(alarm->node.expires, |
| 432 | incr*overrun); |
| 433 | |
| 434 | if (alarm->node.expires.tv64 > now.tv64) |
| 435 | return overrun; |
| 436 | /* |
| 437 | * This (and the ktime_add() below) is the |
| 438 | * correction for exact: |
| 439 | */ |
| 440 | overrun++; |
| 441 | } |
| 442 | |
Thomas Gleixner | 8ee7f06 | 2017-05-30 23:15:34 +0200 | [diff] [blame] | 443 | alarm->node.expires = ktime_add_safe(alarm->node.expires, interval); |
John Stultz | dce75a8 | 2011-08-10 11:31:03 -0700 | [diff] [blame] | 444 | return overrun; |
| 445 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 446 | EXPORT_SYMBOL_GPL(alarm_forward); |
John Stultz | dce75a8 | 2011-08-10 11:31:03 -0700 | [diff] [blame] | 447 | |
Todd Poynor | 6cffe00 | 2013-05-15 14:38:11 -0700 | [diff] [blame] | 448 | u64 alarm_forward_now(struct alarm *alarm, ktime_t interval) |
| 449 | { |
| 450 | struct alarm_base *base = &alarm_bases[alarm->type]; |
| 451 | |
| 452 | return alarm_forward(alarm, base->gettime(), interval); |
| 453 | } |
Marcus Gelderie | 11682a4 | 2013-06-04 09:32:09 +0200 | [diff] [blame] | 454 | EXPORT_SYMBOL_GPL(alarm_forward_now); |
John Stultz | dce75a8 | 2011-08-10 11:31:03 -0700 | [diff] [blame] | 455 | |
| 456 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 457 | /** |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 458 | * clock2alarm - helper that converts from clockid to alarmtypes |
| 459 | * @clockid: clockid. |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 460 | */ |
| 461 | static enum alarmtimer_type clock2alarm(clockid_t clockid) |
| 462 | { |
| 463 | if (clockid == CLOCK_REALTIME_ALARM) |
| 464 | return ALARM_REALTIME; |
| 465 | if (clockid == CLOCK_BOOTTIME_ALARM) |
| 466 | return ALARM_BOOTTIME; |
| 467 | return -1; |
| 468 | } |
| 469 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 470 | /** |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 471 | * alarm_handle_timer - Callback for posix timers |
| 472 | * @alarm: alarm that fired |
| 473 | * |
| 474 | * Posix timer callback for expired alarm timers. |
| 475 | */ |
John Stultz | 4b41308 | 2011-08-10 10:37:59 -0700 | [diff] [blame] | 476 | static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm, |
| 477 | ktime_t now) |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 478 | { |
Richard Larocque | 474e941 | 2014-09-09 18:31:05 -0700 | [diff] [blame] | 479 | unsigned long flags; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 480 | struct k_itimer *ptr = container_of(alarm, struct k_itimer, |
John Stultz | 9e26476 | 2011-08-10 12:09:24 -0700 | [diff] [blame] | 481 | it.alarm.alarmtimer); |
Richard Larocque | 474e941 | 2014-09-09 18:31:05 -0700 | [diff] [blame] | 482 | enum alarmtimer_restart result = ALARMTIMER_NORESTART; |
| 483 | |
| 484 | spin_lock_irqsave(&ptr->it_lock, flags); |
Richard Larocque | 265b81d | 2014-09-09 18:31:04 -0700 | [diff] [blame] | 485 | if ((ptr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) { |
| 486 | if (posix_timer_event(ptr, 0) != 0) |
| 487 | ptr->it_overrun++; |
| 488 | } |
John Stultz | 4b41308 | 2011-08-10 10:37:59 -0700 | [diff] [blame] | 489 | |
John Stultz | 54da23b | 2011-08-10 11:08:07 -0700 | [diff] [blame] | 490 | /* Re-add periodic timers */ |
John Stultz | 9e26476 | 2011-08-10 12:09:24 -0700 | [diff] [blame] | 491 | if (ptr->it.alarm.interval.tv64) { |
| 492 | ptr->it_overrun += alarm_forward(alarm, now, |
| 493 | ptr->it.alarm.interval); |
Richard Larocque | 474e941 | 2014-09-09 18:31:05 -0700 | [diff] [blame] | 494 | result = ALARMTIMER_RESTART; |
John Stultz | 54da23b | 2011-08-10 11:08:07 -0700 | [diff] [blame] | 495 | } |
Richard Larocque | 474e941 | 2014-09-09 18:31:05 -0700 | [diff] [blame] | 496 | spin_unlock_irqrestore(&ptr->it_lock, flags); |
| 497 | |
| 498 | return result; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 499 | } |
| 500 | |
John Stultz | 180bf81 | 2011-04-28 12:58:11 -0700 | [diff] [blame] | 501 | /** |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 502 | * alarm_clock_getres - posix getres interface |
| 503 | * @which_clock: clockid |
| 504 | * @tp: timespec to fill |
| 505 | * |
| 506 | * Returns the granularity of underlying alarm base clock |
| 507 | */ |
| 508 | static int alarm_clock_getres(const clockid_t which_clock, struct timespec *tp) |
| 509 | { |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 510 | if (!alarmtimer_get_rtcdev()) |
KOSAKI Motohiro | 98d6f4d | 2013-10-14 17:33:16 -0400 | [diff] [blame] | 511 | return -EINVAL; |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 512 | |
Thomas Gleixner | 056a3ca | 2015-04-14 21:08:32 +0000 | [diff] [blame] | 513 | tp->tv_sec = 0; |
| 514 | tp->tv_nsec = hrtimer_resolution; |
| 515 | return 0; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 516 | } |
| 517 | |
| 518 | /** |
| 519 | * alarm_clock_get - posix clock_get interface |
| 520 | * @which_clock: clockid |
| 521 | * @tp: timespec to fill. |
| 522 | * |
| 523 | * Provides the underlying alarm base time. |
| 524 | */ |
| 525 | static int alarm_clock_get(clockid_t which_clock, struct timespec *tp) |
| 526 | { |
| 527 | struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; |
| 528 | |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 529 | if (!alarmtimer_get_rtcdev()) |
KOSAKI Motohiro | 98d6f4d | 2013-10-14 17:33:16 -0400 | [diff] [blame] | 530 | return -EINVAL; |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 531 | |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 532 | *tp = ktime_to_timespec(base->gettime()); |
| 533 | return 0; |
| 534 | } |
| 535 | |
| 536 | /** |
| 537 | * alarm_timer_create - posix timer_create interface |
| 538 | * @new_timer: k_itimer pointer to manage |
| 539 | * |
| 540 | * Initializes the k_itimer structure. |
| 541 | */ |
| 542 | static int alarm_timer_create(struct k_itimer *new_timer) |
| 543 | { |
| 544 | enum alarmtimer_type type; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 545 | |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 546 | if (!alarmtimer_get_rtcdev()) |
| 547 | return -ENOTSUPP; |
| 548 | |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 549 | if (!capable(CAP_WAKE_ALARM)) |
| 550 | return -EPERM; |
| 551 | |
| 552 | type = clock2alarm(new_timer->it_clock); |
John Stultz | 9e26476 | 2011-08-10 12:09:24 -0700 | [diff] [blame] | 553 | alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer); |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 554 | return 0; |
| 555 | } |
| 556 | |
| 557 | /** |
| 558 | * alarm_timer_get - posix timer_get interface |
| 559 | * @new_timer: k_itimer pointer |
| 560 | * @cur_setting: itimerspec data to fill |
| 561 | * |
Richard Larocque | e86fea7 | 2014-09-09 18:31:03 -0700 | [diff] [blame] | 562 | * Copies out the current itimerspec data |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 563 | */ |
| 564 | static void alarm_timer_get(struct k_itimer *timr, |
| 565 | struct itimerspec *cur_setting) |
| 566 | { |
Richard Larocque | e86fea7 | 2014-09-09 18:31:03 -0700 | [diff] [blame] | 567 | ktime_t relative_expiry_time = |
| 568 | alarm_expires_remaining(&(timr->it.alarm.alarmtimer)); |
John Stultz | ea7802f | 2011-08-04 07:51:56 -0700 | [diff] [blame] | 569 | |
Richard Larocque | e86fea7 | 2014-09-09 18:31:03 -0700 | [diff] [blame] | 570 | if (ktime_to_ns(relative_expiry_time) > 0) { |
| 571 | cur_setting->it_value = ktime_to_timespec(relative_expiry_time); |
| 572 | } else { |
| 573 | cur_setting->it_value.tv_sec = 0; |
| 574 | cur_setting->it_value.tv_nsec = 0; |
| 575 | } |
| 576 | |
| 577 | cur_setting->it_interval = ktime_to_timespec(timr->it.alarm.interval); |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 578 | } |
| 579 | |
| 580 | /** |
| 581 | * alarm_timer_del - posix timer_del interface |
| 582 | * @timr: k_itimer pointer to be deleted |
| 583 | * |
| 584 | * Cancels any programmed alarms for the given timer. |
| 585 | */ |
| 586 | static int alarm_timer_del(struct k_itimer *timr) |
| 587 | { |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 588 | if (!rtcdev) |
| 589 | return -ENOTSUPP; |
| 590 | |
John Stultz | 9082c46 | 2011-08-10 12:41:36 -0700 | [diff] [blame] | 591 | if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0) |
| 592 | return TIMER_RETRY; |
| 593 | |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 594 | return 0; |
| 595 | } |
| 596 | |
| 597 | /** |
| 598 | * alarm_timer_set - posix timer_set interface |
| 599 | * @timr: k_itimer pointer to be deleted |
| 600 | * @flags: timer flags |
| 601 | * @new_setting: itimerspec to be used |
| 602 | * @old_setting: itimerspec being replaced |
| 603 | * |
| 604 | * Sets the timer to new_setting, and starts the timer. |
| 605 | */ |
| 606 | static int alarm_timer_set(struct k_itimer *timr, int flags, |
| 607 | struct itimerspec *new_setting, |
| 608 | struct itimerspec *old_setting) |
| 609 | { |
John Stultz | 1692777 | 2014-07-07 14:06:11 -0700 | [diff] [blame] | 610 | ktime_t exp; |
| 611 | |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 612 | if (!rtcdev) |
| 613 | return -ENOTSUPP; |
| 614 | |
John Stultz | 1692777 | 2014-07-07 14:06:11 -0700 | [diff] [blame] | 615 | if (flags & ~TIMER_ABSTIME) |
| 616 | return -EINVAL; |
| 617 | |
John Stultz | 971c90b | 2011-08-04 07:25:35 -0700 | [diff] [blame] | 618 | if (old_setting) |
| 619 | alarm_timer_get(timr, old_setting); |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 620 | |
| 621 | /* If the timer was already set, cancel it */ |
John Stultz | 9082c46 | 2011-08-10 12:41:36 -0700 | [diff] [blame] | 622 | if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0) |
| 623 | return TIMER_RETRY; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 624 | |
| 625 | /* start the timer */ |
John Stultz | 9e26476 | 2011-08-10 12:09:24 -0700 | [diff] [blame] | 626 | timr->it.alarm.interval = timespec_to_ktime(new_setting->it_interval); |
Thomas Gleixner | 0465104 | 2017-05-30 23:15:35 +0200 | [diff] [blame] | 627 | |
| 628 | /* |
| 629 | * Rate limit to the tick as a hot fix to prevent DOS. Will be |
| 630 | * mopped up later. |
| 631 | */ |
Greg Hackmann | 91af5f0 | 2017-07-24 10:19:24 -0700 | [diff] [blame] | 632 | if (timr->it.alarm.interval.tv64 && |
| 633 | ktime_to_ns(timr->it.alarm.interval) < TICK_NSEC) |
Thomas Gleixner | 0465104 | 2017-05-30 23:15:35 +0200 | [diff] [blame] | 634 | timr->it.alarm.interval = ktime_set(0, TICK_NSEC); |
| 635 | |
John Stultz | 1692777 | 2014-07-07 14:06:11 -0700 | [diff] [blame] | 636 | exp = timespec_to_ktime(new_setting->it_value); |
| 637 | /* Convert (if necessary) to absolute time */ |
| 638 | if (flags != TIMER_ABSTIME) { |
| 639 | ktime_t now; |
| 640 | |
| 641 | now = alarm_bases[timr->it.alarm.alarmtimer.type].gettime(); |
Thomas Gleixner | 8ee7f06 | 2017-05-30 23:15:34 +0200 | [diff] [blame] | 642 | exp = ktime_add_safe(now, exp); |
John Stultz | 1692777 | 2014-07-07 14:06:11 -0700 | [diff] [blame] | 643 | } |
| 644 | |
| 645 | alarm_start(&timr->it.alarm.alarmtimer, exp); |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 646 | return 0; |
| 647 | } |
| 648 | |
| 649 | /** |
| 650 | * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep |
| 651 | * @alarm: ptr to alarm that fired |
| 652 | * |
| 653 | * Wakes up the task that set the alarmtimer |
| 654 | */ |
John Stultz | 4b41308 | 2011-08-10 10:37:59 -0700 | [diff] [blame] | 655 | static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm, |
| 656 | ktime_t now) |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 657 | { |
| 658 | struct task_struct *task = (struct task_struct *)alarm->data; |
| 659 | |
| 660 | alarm->data = NULL; |
| 661 | if (task) |
| 662 | wake_up_process(task); |
John Stultz | 4b41308 | 2011-08-10 10:37:59 -0700 | [diff] [blame] | 663 | return ALARMTIMER_NORESTART; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 664 | } |
| 665 | |
| 666 | /** |
| 667 | * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation |
| 668 | * @alarm: ptr to alarmtimer |
| 669 | * @absexp: absolute expiration time |
| 670 | * |
| 671 | * Sets the alarm timer and sleeps until it is fired or interrupted. |
| 672 | */ |
| 673 | static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp) |
| 674 | { |
| 675 | alarm->data = (void *)current; |
| 676 | do { |
| 677 | set_current_state(TASK_INTERRUPTIBLE); |
John Stultz | 9e26476 | 2011-08-10 12:09:24 -0700 | [diff] [blame] | 678 | alarm_start(alarm, absexp); |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 679 | if (likely(alarm->data)) |
| 680 | schedule(); |
| 681 | |
| 682 | alarm_cancel(alarm); |
| 683 | } while (alarm->data && !signal_pending(current)); |
| 684 | |
| 685 | __set_current_state(TASK_RUNNING); |
| 686 | |
| 687 | return (alarm->data == NULL); |
| 688 | } |
| 689 | |
| 690 | |
| 691 | /** |
| 692 | * update_rmtp - Update remaining timespec value |
| 693 | * @exp: expiration time |
| 694 | * @type: timer type |
| 695 | * @rmtp: user pointer to remaining timepsec value |
| 696 | * |
| 697 | * Helper function that fills in rmtp value with time between |
| 698 | * now and the exp value |
| 699 | */ |
| 700 | static int update_rmtp(ktime_t exp, enum alarmtimer_type type, |
| 701 | struct timespec __user *rmtp) |
| 702 | { |
| 703 | struct timespec rmt; |
| 704 | ktime_t rem; |
| 705 | |
| 706 | rem = ktime_sub(exp, alarm_bases[type].gettime()); |
| 707 | |
| 708 | if (rem.tv64 <= 0) |
| 709 | return 0; |
| 710 | rmt = ktime_to_timespec(rem); |
| 711 | |
| 712 | if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) |
| 713 | return -EFAULT; |
| 714 | |
| 715 | return 1; |
| 716 | |
| 717 | } |
| 718 | |
| 719 | /** |
| 720 | * alarm_timer_nsleep_restart - restartblock alarmtimer nsleep |
| 721 | * @restart: ptr to restart block |
| 722 | * |
| 723 | * Handles restarted clock_nanosleep calls |
| 724 | */ |
| 725 | static long __sched alarm_timer_nsleep_restart(struct restart_block *restart) |
| 726 | { |
Thomas Gleixner | ab8177b | 2011-05-20 13:05:15 +0200 | [diff] [blame] | 727 | enum alarmtimer_type type = restart->nanosleep.clockid; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 728 | ktime_t exp; |
| 729 | struct timespec __user *rmtp; |
| 730 | struct alarm alarm; |
| 731 | int ret = 0; |
| 732 | |
| 733 | exp.tv64 = restart->nanosleep.expires; |
| 734 | alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); |
| 735 | |
| 736 | if (alarmtimer_do_nsleep(&alarm, exp)) |
| 737 | goto out; |
| 738 | |
| 739 | if (freezing(current)) |
| 740 | alarmtimer_freezerset(exp, type); |
| 741 | |
| 742 | rmtp = restart->nanosleep.rmtp; |
| 743 | if (rmtp) { |
| 744 | ret = update_rmtp(exp, type, rmtp); |
| 745 | if (ret <= 0) |
| 746 | goto out; |
| 747 | } |
| 748 | |
| 749 | |
| 750 | /* The other values in restart are already filled in */ |
| 751 | ret = -ERESTART_RESTARTBLOCK; |
| 752 | out: |
| 753 | return ret; |
| 754 | } |
| 755 | |
| 756 | /** |
| 757 | * alarm_timer_nsleep - alarmtimer nanosleep |
| 758 | * @which_clock: clockid |
| 759 | * @flags: determins abstime or relative |
| 760 | * @tsreq: requested sleep time (abs or rel) |
| 761 | * @rmtp: remaining sleep time saved |
| 762 | * |
| 763 | * Handles clock_nanosleep calls against _ALARM clockids |
| 764 | */ |
| 765 | static int alarm_timer_nsleep(const clockid_t which_clock, int flags, |
| 766 | struct timespec *tsreq, struct timespec __user *rmtp) |
| 767 | { |
| 768 | enum alarmtimer_type type = clock2alarm(which_clock); |
| 769 | struct alarm alarm; |
| 770 | ktime_t exp; |
| 771 | int ret = 0; |
| 772 | struct restart_block *restart; |
| 773 | |
John Stultz | 1c6b39a | 2011-06-16 18:47:37 -0700 | [diff] [blame] | 774 | if (!alarmtimer_get_rtcdev()) |
| 775 | return -ENOTSUPP; |
| 776 | |
John Stultz | 1692777 | 2014-07-07 14:06:11 -0700 | [diff] [blame] | 777 | if (flags & ~TIMER_ABSTIME) |
| 778 | return -EINVAL; |
| 779 | |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 780 | if (!capable(CAP_WAKE_ALARM)) |
| 781 | return -EPERM; |
| 782 | |
| 783 | alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); |
| 784 | |
| 785 | exp = timespec_to_ktime(*tsreq); |
| 786 | /* Convert (if necessary) to absolute time */ |
| 787 | if (flags != TIMER_ABSTIME) { |
| 788 | ktime_t now = alarm_bases[type].gettime(); |
Thomas Gleixner | 747128e | 2018-07-02 09:34:29 +0200 | [diff] [blame^] | 789 | |
| 790 | exp = ktime_add_safe(now, exp); |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 791 | } |
| 792 | |
| 793 | if (alarmtimer_do_nsleep(&alarm, exp)) |
| 794 | goto out; |
| 795 | |
| 796 | if (freezing(current)) |
| 797 | alarmtimer_freezerset(exp, type); |
| 798 | |
| 799 | /* abs timers don't set remaining time or restart */ |
| 800 | if (flags == TIMER_ABSTIME) { |
| 801 | ret = -ERESTARTNOHAND; |
| 802 | goto out; |
| 803 | } |
| 804 | |
| 805 | if (rmtp) { |
| 806 | ret = update_rmtp(exp, type, rmtp); |
| 807 | if (ret <= 0) |
| 808 | goto out; |
| 809 | } |
| 810 | |
Andy Lutomirski | f56141e | 2015-02-12 15:01:14 -0800 | [diff] [blame] | 811 | restart = ¤t->restart_block; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 812 | restart->fn = alarm_timer_nsleep_restart; |
Thomas Gleixner | ab8177b | 2011-05-20 13:05:15 +0200 | [diff] [blame] | 813 | restart->nanosleep.clockid = type; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 814 | restart->nanosleep.expires = exp.tv64; |
| 815 | restart->nanosleep.rmtp = rmtp; |
| 816 | ret = -ERESTART_RESTARTBLOCK; |
| 817 | |
| 818 | out: |
| 819 | return ret; |
| 820 | } |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 821 | |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 822 | |
| 823 | /* Suspend hook structures */ |
| 824 | static const struct dev_pm_ops alarmtimer_pm_ops = { |
| 825 | .suspend = alarmtimer_suspend, |
zhuo-hao | a0e3213 | 2015-11-17 20:08:07 +0800 | [diff] [blame] | 826 | .resume = alarmtimer_resume, |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 827 | }; |
| 828 | |
| 829 | static struct platform_driver alarmtimer_driver = { |
| 830 | .driver = { |
| 831 | .name = "alarmtimer", |
| 832 | .pm = &alarmtimer_pm_ops, |
| 833 | } |
| 834 | }; |
| 835 | |
| 836 | /** |
| 837 | * alarmtimer_init - Initialize alarm timer code |
| 838 | * |
| 839 | * This function initializes the alarm bases and registers |
| 840 | * the posix clock ids. |
| 841 | */ |
| 842 | static int __init alarmtimer_init(void) |
| 843 | { |
Thomas Gleixner | 4523f6a | 2011-09-14 10:54:29 +0200 | [diff] [blame] | 844 | struct platform_device *pdev; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 845 | int error = 0; |
| 846 | int i; |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 847 | struct k_clock alarm_clock = { |
| 848 | .clock_getres = alarm_clock_getres, |
| 849 | .clock_get = alarm_clock_get, |
| 850 | .timer_create = alarm_timer_create, |
| 851 | .timer_set = alarm_timer_set, |
| 852 | .timer_del = alarm_timer_del, |
| 853 | .timer_get = alarm_timer_get, |
| 854 | .nsleep = alarm_timer_nsleep, |
| 855 | }; |
| 856 | |
Thomas Gleixner | c5e14e7 | 2012-03-24 12:46:23 +0100 | [diff] [blame] | 857 | alarmtimer_rtc_timer_init(); |
John Stultz | ad30dfa | 2012-03-23 15:52:25 -0700 | [diff] [blame] | 858 | |
John Stultz | 9a7adcf | 2011-01-11 09:54:33 -0800 | [diff] [blame] | 859 | posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock); |
| 860 | posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 861 | |
| 862 | /* Initialize alarm bases */ |
| 863 | alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; |
| 864 | alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real; |
| 865 | alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; |
| 866 | alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime; |
| 867 | for (i = 0; i < ALARM_NUMTYPE; i++) { |
| 868 | timerqueue_init_head(&alarm_bases[i].timerqueue); |
| 869 | spin_lock_init(&alarm_bases[i].lock); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 870 | } |
John Stultz | 8bc0daf | 2011-07-14 18:35:13 -0700 | [diff] [blame] | 871 | |
Thomas Gleixner | 4523f6a | 2011-09-14 10:54:29 +0200 | [diff] [blame] | 872 | error = alarmtimer_rtc_interface_setup(); |
| 873 | if (error) |
| 874 | return error; |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 875 | |
Thomas Gleixner | 4523f6a | 2011-09-14 10:54:29 +0200 | [diff] [blame] | 876 | error = platform_driver_register(&alarmtimer_driver); |
| 877 | if (error) |
| 878 | goto out_if; |
| 879 | |
| 880 | pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0); |
| 881 | if (IS_ERR(pdev)) { |
| 882 | error = PTR_ERR(pdev); |
| 883 | goto out_drv; |
| 884 | } |
Todd Poynor | 59a93c2 | 2012-08-09 00:37:27 -0700 | [diff] [blame] | 885 | ws = wakeup_source_register("alarmtimer"); |
Thomas Gleixner | 4523f6a | 2011-09-14 10:54:29 +0200 | [diff] [blame] | 886 | return 0; |
| 887 | |
| 888 | out_drv: |
| 889 | platform_driver_unregister(&alarmtimer_driver); |
| 890 | out_if: |
| 891 | alarmtimer_rtc_interface_remove(); |
John Stultz | ff3ead9 | 2011-01-11 09:42:13 -0800 | [diff] [blame] | 892 | return error; |
| 893 | } |
| 894 | device_initcall(alarmtimer_init); |