diff options
Diffstat (limited to 'drivers/staging/android/alarm.c')
| -rw-r--r-- | drivers/staging/android/alarm.c | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/drivers/staging/android/alarm.c b/drivers/staging/android/alarm.c new file mode 100644 index 000000000000..c68950b9e08f --- /dev/null +++ b/drivers/staging/android/alarm.c @@ -0,0 +1,601 @@ +/* drivers/rtc/alarm.c + * + * Copyright (C) 2007-2009 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <linux/time.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/miscdevice.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> +#include <linux/sched.h> +#include <linux/spinlock.h> +#include "android_alarm.h" + +/* XXX - Hack out wakelocks, while they are out of tree */ +struct wake_lock { + int i; +}; +#define wake_lock(x) +#define wake_lock_timeout(x, y) +#define wake_unlock(x) +#define WAKE_LOCK_SUSPEND 0 +#define wake_lock_init(x, y, z) ((x)->i = 1) +#define wake_lock_destroy(x) + +#define ANDROID_ALARM_PRINT_ERROR (1U << 0) +#define ANDROID_ALARM_PRINT_INIT_STATUS (1U << 1) +#define ANDROID_ALARM_PRINT_TSET (1U << 2) +#define ANDROID_ALARM_PRINT_CALL (1U << 3) +#define ANDROID_ALARM_PRINT_SUSPEND (1U << 4) +#define ANDROID_ALARM_PRINT_INT (1U << 5) +#define ANDROID_ALARM_PRINT_FLOW (1U << 6) + +static int debug_mask = ANDROID_ALARM_PRINT_ERROR | \ + ANDROID_ALARM_PRINT_INIT_STATUS; +module_param_named(debug_mask, debug_mask, int, S_IRUGO | S_IWUSR | S_IWGRP); + +#define pr_alarm(debug_level_mask, args...) \ + do { \ + if (debug_mask & ANDROID_ALARM_PRINT_##debug_level_mask) { \ + pr_info(args); \ + } \ + } while (0) + +#define ANDROID_ALARM_WAKEUP_MASK ( \ + ANDROID_ALARM_RTC_WAKEUP_MASK | \ + ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP_MASK) + +/* support old usespace code */ +#define ANDROID_ALARM_SET_OLD _IOW('a', 2, time_t) /* set alarm */ +#define ANDROID_ALARM_SET_AND_WAIT_OLD _IOW('a', 3, time_t) + +struct alarm_queue { + struct rb_root alarms; + struct rb_node *first; + struct hrtimer timer; + ktime_t delta; + bool stopped; + ktime_t stopped_time; +}; + +static struct rtc_device *alarm_rtc_dev; +static DEFINE_SPINLOCK(alarm_slock); +static DEFINE_MUTEX(alarm_setrtc_mutex); +static struct wake_lock alarm_rtc_wake_lock; +static struct platform_device *alarm_platform_dev; +struct alarm_queue alarms[ANDROID_ALARM_TYPE_COUNT]; +static bool suspended; + +static void update_timer_locked(struct alarm_queue *base, bool head_removed) +{ + struct android_alarm *alarm; + bool is_wakeup = base == &alarms[ANDROID_ALARM_RTC_WAKEUP] || + base == &alarms[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP]; + + if (base->stopped) { + pr_alarm(FLOW, "changed alarm while setting the wall time\n"); + return; + } + + if (is_wakeup && !suspended && head_removed) + wake_unlock(&alarm_rtc_wake_lock); + + if (!base->first) + return; + + alarm = container_of(base->first, struct android_alarm, node); + + pr_alarm(FLOW, "selected alarm, type %d, func %pF at %lld\n", + alarm->type, alarm->function, ktime_to_ns(alarm->expires)); + + if (is_wakeup && suspended) { + pr_alarm(FLOW, "changed alarm while suspened\n"); + wake_lock_timeout(&alarm_rtc_wake_lock, 1 * HZ); + return; + } + + hrtimer_try_to_cancel(&base->timer); + base->timer.node.expires = ktime_add(base->delta, alarm->expires); + base->timer._softexpires = ktime_add(base->delta, alarm->softexpires); + hrtimer_start_expires(&base->timer, HRTIMER_MODE_ABS); +} + +static void alarm_enqueue_locked(struct android_alarm *alarm) +{ + struct alarm_queue *base = &alarms[alarm->type]; + struct rb_node **link = &base->alarms.rb_node; + struct rb_node *parent = NULL; + struct android_alarm *entry; + int leftmost = 1; + bool was_first = false; + + pr_alarm(FLOW, "added alarm, type %d, func %pF at %lld\n", + alarm->type, alarm->function, ktime_to_ns(alarm->expires)); + + if (base->first == &alarm->node) { + base->first = rb_next(&alarm->node); + was_first = true; + } + if (!RB_EMPTY_NODE(&alarm->node)) { + rb_erase(&alarm->node, &base->alarms); + RB_CLEAR_NODE(&alarm->node); + } + + while (*link) { + parent = *link; + entry = rb_entry(parent, struct android_alarm, node); + /* + * We dont care about collisions. Nodes with + * the same expiry time stay together. + */ + if (alarm->expires.tv64 < entry->expires.tv64) { + link = &(*link)->rb_left; + } else { + link = &(*link)->rb_right; + leftmost = 0; + } + } + if (leftmost) + base->first = &alarm->node; + if (leftmost || was_first) + update_timer_locked(base, was_first); + + rb_link_node(&alarm->node, parent, link); + rb_insert_color(&alarm->node, &base->alarms); +} + +/** + * android_alarm_init - initialize an alarm + * @alarm: the alarm to be initialized + * @type: the alarm type to be used + * @function: alarm callback function + */ +void android_alarm_init(struct android_alarm *alarm, + enum android_alarm_type type, void (*function)(struct android_alarm *)) +{ + RB_CLEAR_NODE(&alarm->node); + alarm->type = type; + alarm->function = function; + + pr_alarm(FLOW, "created alarm, type %d, func %pF\n", type, function); +} + + +/** + * android_alarm_start_range - (re)start an alarm + * @alarm: the alarm to be added + * @start: earliest expiry time + * @end: expiry time + */ +void android_alarm_start_range(struct android_alarm *alarm, ktime_t start, + ktime_t end) +{ + unsigned long flags; + + spin_lock_irqsave(&alarm_slock, flags); + alarm->softexpires = start; + alarm->expires = end; + alarm_enqueue_locked(alarm); + spin_unlock_irqrestore(&alarm_slock, flags); +} + +/** + * android_alarm_try_to_cancel - try to deactivate an alarm + * @alarm: alarm to stop + * + * Returns: + * 0 when the alarm was not active + * 1 when the alarm was active + * -1 when the alarm may currently be excuting the callback function and + * cannot be stopped (it may also be inactive) + */ +int android_alarm_try_to_cancel(struct android_alarm *alarm) +{ + struct alarm_queue *base = &alarms[alarm->type]; + unsigned long flags; + bool first = false; + int ret = 0; + + spin_lock_irqsave(&alarm_slock, flags); + if (!RB_EMPTY_NODE(&alarm->node)) { + pr_alarm(FLOW, "canceled alarm, type %d, func %pF at %lld\n", + alarm->type, alarm->function, + ktime_to_ns(alarm->expires)); + ret = 1; + if (base->first == &alarm->node) { + base->first = rb_next(&alarm->node); + first = true; + } + rb_erase(&alarm->node, &base->alarms); + RB_CLEAR_NODE(&alarm->node); + if (first) + update_timer_locked(base, true); + } else + pr_alarm(FLOW, "tried to cancel alarm, type %d, func %pF\n", + alarm->type, alarm->function); + spin_unlock_irqrestore(&alarm_slock, flags); + if (!ret && hrtimer_callback_running(&base->timer)) + ret = -1; + return ret; +} + +/** + * android_alarm_cancel - cancel an alarm and wait for the handler to finish. + * @alarm: the alarm to be cancelled + * + * Returns: + * 0 when the alarm was not active + * 1 when the alarm was active + */ +int android_alarm_cancel(struct android_alarm *alarm) +{ + for (;;) { + int ret = android_alarm_try_to_cancel(alarm); + if (ret >= 0) + return ret; + cpu_relax(); + } +} + +/** + * alarm_set_rtc - set the kernel and rtc walltime + * @new_time: timespec value containing the new time + */ +int android_alarm_set_rtc(struct timespec new_time) +{ + int i; + int ret; + unsigned long flags; + struct rtc_time rtc_new_rtc_time; + struct timespec tmp_time; + + rtc_time_to_tm(new_time.tv_sec, &rtc_new_rtc_time); + + pr_alarm(TSET, "set rtc %ld %ld - rtc %02d:%02d:%02d %02d/%02d/%04d\n", + new_time.tv_sec, new_time.tv_nsec, + rtc_new_rtc_time.tm_hour, rtc_new_rtc_time.tm_min, + rtc_new_rtc_time.tm_sec, rtc_new_rtc_time.tm_mon + 1, + rtc_new_rtc_time.tm_mday, + rtc_new_rtc_time.tm_year + 1900); + + mutex_lock(&alarm_setrtc_mutex); + spin_lock_irqsave(&alarm_slock, flags); + wake_lock(&alarm_rtc_wake_lock); + getnstimeofday(&tmp_time); + for (i = 0; i < ANDROID_ALARM_SYSTEMTIME; i++) { + hrtimer_try_to_cancel(&alarms[i].timer); + alarms[i].stopped = true; + alarms[i].stopped_time = timespec_to_ktime(tmp_time); + } + alarms[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP].delta = + alarms[ANDROID_ALARM_ELAPSED_REALTIME].delta = + ktime_sub(alarms[ANDROID_ALARM_ELAPSED_REALTIME].delta, + timespec_to_ktime(timespec_sub(tmp_time, new_time))); + spin_unlock_irqrestore(&alarm_slock, flags); + ret = do_settimeofday(&new_time); + spin_lock_irqsave(&alarm_slock, flags); + for (i = 0; i < ANDROID_ALARM_SYSTEMTIME; i++) { + alarms[i].stopped = false; + update_timer_locked(&alarms[i], false); + } + spin_unlock_irqrestore(&alarm_slock, flags); + if (ret < 0) { + pr_alarm(ERROR, "alarm_set_rtc: Failed to set time\n"); + goto err; + } + if (!alarm_rtc_dev) { + pr_alarm(ERROR, + "alarm_set_rtc: no RTC, time will be lost on reboot\n"); + goto err; + } + ret = rtc_set_time(alarm_rtc_dev, &rtc_new_rtc_time); + if (ret < 0) + pr_alarm(ERROR, "alarm_set_rtc: " + "Failed to set RTC, time will be lost on reboot\n"); +err: + wake_unlock(&alarm_rtc_wake_lock); + mutex_unlock(&alarm_setrtc_mutex); + return ret; +} + +/** + * alarm_get_elapsed_realtime - get the elapsed real time in ktime_t format + * + * returns the time in ktime_t format + */ +ktime_t alarm_get_elapsed_realtime(void) +{ + ktime_t now; + unsigned long flags; + struct alarm_queue *base = &alarms[ANDROID_ALARM_ELAPSED_REALTIME]; + + spin_lock_irqsave(&alarm_slock, flags); + now = base->stopped ? base->stopped_time : ktime_get_real(); + now = ktime_sub(now, base->delta); + spin_unlock_irqrestore(&alarm_slock, flags); + return now; +} + +static enum hrtimer_restart alarm_timer_triggered(struct hrtimer *timer) +{ + struct alarm_queue *base; + struct android_alarm *alarm; + unsigned long flags; + ktime_t now; + + spin_lock_irqsave(&alarm_slock, flags); + + base = container_of(timer, struct alarm_queue, timer); + now = base->stopped ? base->stopped_time : hrtimer_cb_get_time(timer); + now = ktime_sub(now, base->delta); + + pr_alarm(INT, "alarm_timer_triggered type %ld at %lld\n", + base - alarms, ktime_to_ns(now)); + + while (base->first) { + alarm = container_of(base->first, struct android_alarm, node); + if (alarm->softexpires.tv64 > now.tv64) { + pr_alarm(FLOW, "don't call alarm, %pF, %lld (s %lld)\n", + alarm->function, ktime_to_ns(alarm->expires), + ktime_to_ns(alarm->softexpires)); + break; + } + base->first = rb_next(&alarm->node); + rb_erase(&alarm->node, &base->alarms); + RB_CLEAR_NODE(&alarm->node); + pr_alarm(CALL, "call alarm, type %d, func %pF, %lld (s %lld)\n", + alarm->type, alarm->function, + ktime_to_ns(alarm->expires), + ktime_to_ns(alarm->softexpires)); + spin_unlock_irqrestore(&alarm_slock, flags); + alarm->function(alarm); + spin_lock_irqsave(&alarm_slock, flags); + } + if (!base->first) + pr_alarm(FLOW, "no more alarms of type %ld\n", base - alarms); + update_timer_locked(base, true); + spin_unlock_irqrestore(&alarm_slock, flags); + return HRTIMER_NORESTART; +} + +static void alarm_triggered_func(void *p) +{ + struct rtc_device *rtc = alarm_rtc_dev; + if (!(rtc->irq_data & RTC_AF)) + return; + pr_alarm(INT, "rtc alarm triggered\n"); + wake_lock_timeout(&alarm_rtc_wake_lock, 1 * HZ); +} + +static int alarm_suspend(struct platform_device *pdev, pm_message_t state) +{ + int err = 0; + unsigned long flags; + struct rtc_wkalrm rtc_alarm; + struct rtc_time rtc_current_rtc_time; + unsigned long rtc_current_time; + unsigned long rtc_alarm_time; + struct timespec rtc_delta; + struct timespec wall_time; + struct alarm_queue *wakeup_queue = NULL; + struct alarm_queue *tmp_queue = NULL; + + pr_alarm(SUSPEND, "alarm_suspend(%p, %d)\n", pdev, state.event); + + spin_lock_irqsave(&alarm_slock, flags); + suspended = true; + spin_unlock_irqrestore(&alarm_slock, flags); + + hrtimer_cancel(&alarms[ANDROID_ALARM_RTC_WAKEUP].timer); + hrtimer_cancel(&alarms[ + ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP].timer); + + tmp_queue = &alarms[ANDROID_ALARM_RTC_WAKEUP]; + if (tmp_queue->first) + wakeup_queue = tmp_queue; + tmp_queue = &alarms[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP]; + if (tmp_queue->first && (!wakeup_queue || + hrtimer_get_expires(&tmp_queue->timer).tv64 < + hrtimer_get_expires(&wakeup_queue->timer).tv64)) + wakeup_queue = tmp_queue; + if (wakeup_queue) { + rtc_read_time(alarm_rtc_dev, &rtc_current_rtc_time); + getnstimeofday(&wall_time); + rtc_tm_to_time(&rtc_current_rtc_time, &rtc_current_time); + set_normalized_timespec(&rtc_delta, + wall_time.tv_sec - rtc_current_time, + wall_time.tv_nsec); + + rtc_alarm_time = timespec_sub(ktime_to_timespec( + hrtimer_get_expires(&wakeup_queue->timer)), + rtc_delta).tv_sec; + + rtc_time_to_tm(rtc_alarm_time, &rtc_alarm.time); + rtc_alarm.enabled = 1; + rtc_set_alarm(alarm_rtc_dev, &rtc_alarm); + rtc_read_time(alarm_rtc_dev, &rtc_current_rtc_time); + rtc_tm_to_time(&rtc_current_rtc_time, &rtc_current_time); + pr_alarm(SUSPEND, + "rtc alarm set at %ld, now %ld, rtc delta %ld.%09ld\n", + rtc_alarm_time, rtc_current_time, + rtc_delta.tv_sec, rtc_delta.tv_nsec); + if (rtc_current_time + 1 >= rtc_alarm_time) { + pr_alarm(SUSPEND, "alarm about to go off\n"); + memset(&rtc_alarm, 0, sizeof(rtc_alarm)); + rtc_alarm.enabled = 0; + rtc_set_alarm(alarm_rtc_dev, &rtc_alarm); + + spin_lock_irqsave(&alarm_slock, flags); + suspended = false; + wake_lock_timeout(&alarm_rtc_wake_lock, 2 * HZ); + update_timer_locked(&alarms[ANDROID_ALARM_RTC_WAKEUP], + false); + update_timer_locked(&alarms[ + ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP], false); + err = -EBUSY; + spin_unlock_irqrestore(&alarm_slock, flags); + } + } + return err; +} + +static int alarm_resume(struct platform_device *pdev) +{ + struct rtc_wkalrm alarm; + unsigned long flags; + + pr_alarm(SUSPEND, "alarm_resume(%p)\n", pdev); + + memset(&alarm, 0, sizeof(alarm)); + alarm.enabled = 0; + rtc_set_alarm(alarm_rtc_dev, &alarm); + + spin_lock_irqsave(&alarm_slock, flags); + suspended = false; + update_timer_locked(&alarms[ANDROID_ALARM_RTC_WAKEUP], false); + update_timer_locked(&alarms[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP], + false); + spin_unlock_irqrestore(&alarm_slock, flags); + + return 0; +} + +static struct rtc_task alarm_rtc_task = { + .func = alarm_triggered_func +}; + +static int rtc_alarm_add_device(struct device *dev, + struct class_interface *class_intf) +{ + int err; + struct rtc_device *rtc = to_rtc_device(dev); + + mutex_lock(&alarm_setrtc_mutex); + + if (alarm_rtc_dev) { + err = -EBUSY; + goto err1; + } + + alarm_platform_dev = + platform_device_register_simple("alarm", -1, NULL, 0); + if (IS_ERR(alarm_platform_dev)) { + err = PTR_ERR(alarm_platform_dev); + goto err2; + } + err = rtc_irq_register(rtc, &alarm_rtc_task); + if (err) + goto err3; + alarm_rtc_dev = rtc; + pr_alarm(INIT_STATUS, "using rtc device, %s, for alarms", rtc->name); + mutex_unlock(&alarm_setrtc_mutex); + + return 0; + +err3: + platform_device_unregister(alarm_platform_dev); +err2: +err1: + mutex_unlock(&alarm_setrtc_mutex); + return err; +} + +static void rtc_alarm_remove_device(struct device *dev, + struct class_interface *class_intf) +{ + if (dev == &alarm_rtc_dev->dev) { + pr_alarm(INIT_STATUS, "lost rtc device for alarms"); + rtc_irq_unregister(alarm_rtc_dev, &alarm_rtc_task); + platform_device_unregister(alarm_platform_dev); + alarm_rtc_dev = NULL; + } +} + +static struct class_interface rtc_alarm_interface = { + .add_dev = &rtc_alarm_add_device, + .remove_dev = &rtc_alarm_remove_device, +}; + +static struct platform_driver alarm_driver = { + .suspend = alarm_suspend, + .resume = alarm_resume, + .driver = { + .name = "alarm" + } +}; + +static int __init alarm_late_init(void) +{ + unsigned long flags; + struct timespec tmp_time, system_time; + + /* this needs to run after the rtc is read at boot */ + spin_lock_irqsave(&alarm_slock, flags); + /* We read the current rtc and system time so we can later calulate + * elasped realtime to be (boot_systemtime + rtc - boot_rtc) == + * (rtc - (boot_rtc - boot_systemtime)) + */ + getnstimeofday(&tmp_time); + ktime_get_ts(&system_time); + alarms[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP].delta = + alarms[ANDROID_ALARM_ELAPSED_REALTIME].delta = + timespec_to_ktime(timespec_sub(tmp_time, system_time)); + + spin_unlock_irqrestore(&alarm_slock, flags); + return 0; +} + +static int __init alarm_driver_init(void) +{ + int err; + int i; + + for (i = 0; i < ANDROID_ALARM_SYSTEMTIME; i++) { + hrtimer_init(&alarms[i].timer, + CLOCK_REALTIME, HRTIMER_MODE_ABS); + alarms[i].timer.function = alarm_timer_triggered; + } + hrtimer_init(&alarms[ANDROID_ALARM_SYSTEMTIME].timer, + CLOCK_MONOTONIC, HRTIMER_MODE_ABS); + alarms[ANDROID_ALARM_SYSTEMTIME].timer.function = alarm_timer_triggered; + err = platform_driver_register(&alarm_driver); + if (err < 0) + goto err1; + wake_lock_init(&alarm_rtc_wake_lock, WAKE_LOCK_SUSPEND, "alarm_rtc"); + rtc_alarm_interface.class = rtc_class; + err = class_interface_register(&rtc_alarm_interface); + if (err < 0) + goto err2; + + return 0; + +err2: + wake_lock_destroy(&alarm_rtc_wake_lock); + platform_driver_unregister(&alarm_driver); +err1: + return err; +} + +static void __exit alarm_exit(void) +{ + class_interface_unregister(&rtc_alarm_interface); + wake_lock_destroy(&alarm_rtc_wake_lock); + platform_driver_unregister(&alarm_driver); +} + +late_initcall(alarm_late_init); +module_init(alarm_driver_init); +module_exit(alarm_exit); + |