Commit 841cb11c authored by Arve Hjønnevåg's avatar Arve Hjønnevåg Committed by Greg Kroah-Hartman

staging: android-alarm: Add android alarm driver & in-kernel alarm interface

Drivers can now create alarms that will use an hrtimer while the
system is running and the rtc to wake up from suspend.

CC: Arve Hjønnevåg <arve@android.com>
CC: Android Kernel Team <kernel-team@android.com>
Signed-off-by: default avatarArve Hjønnevåg <arve@android.com>
[Fold and move alarm driver and interface to staging,
 fix whitespace issue, drop kconfig & make file changes
 as it currently doesn't build  -jstultz]
Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 242501ce
/* drivers/rtc/alarm-dev.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 <asm/mach/time.h>
#include <linux/device.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/sysdev.h>
#include <linux/uaccess.h>
#include <linux/wakelock.h>
#include "android_alarm.h"
#define ANDROID_ALARM_PRINT_INFO (1U << 0)
#define ANDROID_ALARM_PRINT_IO (1U << 1)
#define ANDROID_ALARM_PRINT_INT (1U << 2)
static int debug_mask = ANDROID_ALARM_PRINT_INFO;
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)
static int alarm_opened;
static DEFINE_SPINLOCK(alarm_slock);
static struct wake_lock alarm_wake_lock;
static DECLARE_WAIT_QUEUE_HEAD(alarm_wait_queue);
static uint32_t alarm_pending;
static uint32_t alarm_enabled;
static uint32_t wait_pending;
static struct alarm alarms[ANDROID_ALARM_TYPE_COUNT];
static long alarm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
int rv = 0;
unsigned long flags;
struct timespec new_alarm_time;
struct timespec new_rtc_time;
struct timespec tmp_time;
enum android_alarm_type alarm_type = ANDROID_ALARM_IOCTL_TO_TYPE(cmd);
uint32_t alarm_type_mask = 1U << alarm_type;
if (alarm_type >= ANDROID_ALARM_TYPE_COUNT)
return -EINVAL;
if (ANDROID_ALARM_BASE_CMD(cmd) != ANDROID_ALARM_GET_TIME(0)) {
if ((file->f_flags & O_ACCMODE) == O_RDONLY)
return -EPERM;
if (file->private_data == NULL &&
cmd != ANDROID_ALARM_SET_RTC) {
spin_lock_irqsave(&alarm_slock, flags);
if (alarm_opened) {
spin_unlock_irqrestore(&alarm_slock, flags);
return -EBUSY;
}
alarm_opened = 1;
file->private_data = (void *)1;
spin_unlock_irqrestore(&alarm_slock, flags);
}
}
switch (ANDROID_ALARM_BASE_CMD(cmd)) {
case ANDROID_ALARM_CLEAR(0):
spin_lock_irqsave(&alarm_slock, flags);
pr_alarm(IO, "alarm %d clear\n", alarm_type);
alarm_try_to_cancel(&alarms[alarm_type]);
if (alarm_pending) {
alarm_pending &= ~alarm_type_mask;
if (!alarm_pending && !wait_pending)
wake_unlock(&alarm_wake_lock);
}
alarm_enabled &= ~alarm_type_mask;
spin_unlock_irqrestore(&alarm_slock, flags);
break;
case ANDROID_ALARM_SET_OLD:
case ANDROID_ALARM_SET_AND_WAIT_OLD:
if (get_user(new_alarm_time.tv_sec, (int __user *)arg)) {
rv = -EFAULT;
goto err1;
}
new_alarm_time.tv_nsec = 0;
goto from_old_alarm_set;
case ANDROID_ALARM_SET_AND_WAIT(0):
case ANDROID_ALARM_SET(0):
if (copy_from_user(&new_alarm_time, (void __user *)arg,
sizeof(new_alarm_time))) {
rv = -EFAULT;
goto err1;
}
from_old_alarm_set:
spin_lock_irqsave(&alarm_slock, flags);
pr_alarm(IO, "alarm %d set %ld.%09ld\n", alarm_type,
new_alarm_time.tv_sec, new_alarm_time.tv_nsec);
alarm_enabled |= alarm_type_mask;
alarm_start_range(&alarms[alarm_type],
timespec_to_ktime(new_alarm_time),
timespec_to_ktime(new_alarm_time));
spin_unlock_irqrestore(&alarm_slock, flags);
if (ANDROID_ALARM_BASE_CMD(cmd) != ANDROID_ALARM_SET_AND_WAIT(0)
&& cmd != ANDROID_ALARM_SET_AND_WAIT_OLD)
break;
/* fall though */
case ANDROID_ALARM_WAIT:
spin_lock_irqsave(&alarm_slock, flags);
pr_alarm(IO, "alarm wait\n");
if (!alarm_pending && wait_pending) {
wake_unlock(&alarm_wake_lock);
wait_pending = 0;
}
spin_unlock_irqrestore(&alarm_slock, flags);
rv = wait_event_interruptible(alarm_wait_queue, alarm_pending);
if (rv)
goto err1;
spin_lock_irqsave(&alarm_slock, flags);
rv = alarm_pending;
wait_pending = 1;
alarm_pending = 0;
spin_unlock_irqrestore(&alarm_slock, flags);
break;
case ANDROID_ALARM_SET_RTC:
if (copy_from_user(&new_rtc_time, (void __user *)arg,
sizeof(new_rtc_time))) {
rv = -EFAULT;
goto err1;
}
rv = alarm_set_rtc(new_rtc_time);
spin_lock_irqsave(&alarm_slock, flags);
alarm_pending |= ANDROID_ALARM_TIME_CHANGE_MASK;
wake_up(&alarm_wait_queue);
spin_unlock_irqrestore(&alarm_slock, flags);
if (rv < 0)
goto err1;
break;
case ANDROID_ALARM_GET_TIME(0):
switch (alarm_type) {
case ANDROID_ALARM_RTC_WAKEUP:
case ANDROID_ALARM_RTC:
getnstimeofday(&tmp_time);
break;
case ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP:
case ANDROID_ALARM_ELAPSED_REALTIME:
tmp_time =
ktime_to_timespec(alarm_get_elapsed_realtime());
break;
case ANDROID_ALARM_TYPE_COUNT:
case ANDROID_ALARM_SYSTEMTIME:
ktime_get_ts(&tmp_time);
break;
}
if (copy_to_user((void __user *)arg, &tmp_time,
sizeof(tmp_time))) {
rv = -EFAULT;
goto err1;
}
break;
default:
rv = -EINVAL;
goto err1;
}
err1:
return rv;
}
static int alarm_open(struct inode *inode, struct file *file)
{
file->private_data = NULL;
return 0;
}
static int alarm_release(struct inode *inode, struct file *file)
{
int i;
unsigned long flags;
spin_lock_irqsave(&alarm_slock, flags);
if (file->private_data != 0) {
for (i = 0; i < ANDROID_ALARM_TYPE_COUNT; i++) {
uint32_t alarm_type_mask = 1U << i;
if (alarm_enabled & alarm_type_mask) {
pr_alarm(INFO, "alarm_release: clear alarm, "
"pending %d\n",
!!(alarm_pending & alarm_type_mask));
alarm_enabled &= ~alarm_type_mask;
}
spin_unlock_irqrestore(&alarm_slock, flags);
alarm_cancel(&alarms[i]);
spin_lock_irqsave(&alarm_slock, flags);
}
if (alarm_pending | wait_pending) {
if (alarm_pending)
pr_alarm(INFO, "alarm_release: clear "
"pending alarms %x\n", alarm_pending);
wake_unlock(&alarm_wake_lock);
wait_pending = 0;
alarm_pending = 0;
}
alarm_opened = 0;
}
spin_unlock_irqrestore(&alarm_slock, flags);
return 0;
}
static void alarm_triggered(struct alarm *alarm)
{
unsigned long flags;
uint32_t alarm_type_mask = 1U << alarm->type;
pr_alarm(INT, "alarm_triggered type %d\n", alarm->type);
spin_lock_irqsave(&alarm_slock, flags);
if (alarm_enabled & alarm_type_mask) {
wake_lock_timeout(&alarm_wake_lock, 5 * HZ);
alarm_enabled &= ~alarm_type_mask;
alarm_pending |= alarm_type_mask;
wake_up(&alarm_wait_queue);
}
spin_unlock_irqrestore(&alarm_slock, flags);
}
static const struct file_operations alarm_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = alarm_ioctl,
.open = alarm_open,
.release = alarm_release,
};
static struct miscdevice alarm_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = "alarm",
.fops = &alarm_fops,
};
static int __init alarm_dev_init(void)
{
int err;
int i;
err = misc_register(&alarm_device);
if (err)
return err;
for (i = 0; i < ANDROID_ALARM_TYPE_COUNT; i++)
alarm_init(&alarms[i], i, alarm_triggered);
wake_lock_init(&alarm_wake_lock, WAKE_LOCK_SUSPEND, "alarm");
return 0;
}
static void __exit alarm_dev_exit(void)
{
misc_deregister(&alarm_device);
wake_lock_destroy(&alarm_wake_lock);
}
module_init(alarm_dev_init);
module_exit(alarm_dev_exit);
/* 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 <asm/mach/time.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 <linux/sysdev.h>
#include <linux/wakelock.h>
#include "android_alarm.h"
#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 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 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 alarm *alarm)
{
struct alarm_queue *base = &alarms[alarm->type];
struct rb_node **link = &base->alarms.rb_node;
struct rb_node *parent = NULL;
struct alarm *entry;
int leftmost = 1;
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);
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 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;
update_timer_locked(base, false);
}
rb_link_node(&alarm->node, parent, link);
rb_insert_color(&alarm->node, &base->alarms);
}
/**
* alarm_init - initialize an alarm
* @alarm: the alarm to be initialized
* @type: the alarm type to be used
* @function: alarm callback function
*/
void alarm_init(struct alarm *alarm,
enum android_alarm_type type, void (*function)(struct alarm *))
{
RB_CLEAR_NODE(&alarm->node);
alarm->type = type;
alarm->function = function;
pr_alarm(FLOW, "created alarm, type %d, func %pF\n", type, function);
}
/**
* alarm_start_range - (re)start an alarm
* @alarm: the alarm to be added
* @start: earliest expiry time
* @end: expiry time
*/
void alarm_start_range(struct 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);
}
/**
* 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 alarm_try_to_cancel(struct 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;
}
/**
* 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 alarm_cancel(struct alarm *alarm)
{
for (;;) {
int ret = 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 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 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 %d at %lld\n",
base - alarms, ktime_to_ns(now));
while (base->first) {
alarm = container_of(base->first, struct 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 %d\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_current_timespec;
struct timespec rtc_delta;
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_MASK].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);
rtc_current_timespec.tv_nsec = 0;
rtc_tm_to_time(&rtc_current_rtc_time,
&rtc_current_timespec.tv_sec);
save_time_delta(&rtc_delta, &rtc_current_timespec);
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);
/* include/linux/android_alarm.h
*
* Copyright (C) 2006-2007 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.
*
*/
#ifndef _LINUX_ANDROID_ALARM_H
#define _LINUX_ANDROID_ALARM_H
#include <linux/ioctl.h>
#include <linux/time.h>
enum android_alarm_type {
/* return code bit numbers or set alarm arg */
ANDROID_ALARM_RTC_WAKEUP,
ANDROID_ALARM_RTC,
ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP,
ANDROID_ALARM_ELAPSED_REALTIME,
ANDROID_ALARM_SYSTEMTIME,
ANDROID_ALARM_TYPE_COUNT,
/* return code bit numbers */
/* ANDROID_ALARM_TIME_CHANGE = 16 */
};
#ifdef __KERNEL__
#include <linux/ktime.h>
#include <linux/rbtree.h>
/*
* The alarm interface is similar to the hrtimer interface but adds support
* for wakeup from suspend. It also adds an elapsed realtime clock that can
* be used for periodic timers that need to keep runing while the system is
* suspended and not be disrupted when the wall time is set.
*/
/**
* struct alarm - the basic alarm structure
* @node: red black tree node for time ordered insertion
* @type: alarm type. rtc/elapsed-realtime/systemtime, wakeup/non-wakeup.
* @softexpires: the absolute earliest expiry time of the alarm.
* @expires: the absolute expiry time.
* @function: alarm expiry callback function
*
* The alarm structure must be initialized by alarm_init()
*
*/
struct alarm {
struct rb_node node;
enum android_alarm_type type;
ktime_t softexpires;
ktime_t expires;
void (*function)(struct alarm *);
};
void alarm_init(struct alarm *alarm,
enum android_alarm_type type, void (*function)(struct alarm *));
void alarm_start_range(struct alarm *alarm, ktime_t start, ktime_t end);
int alarm_try_to_cancel(struct alarm *alarm);
int alarm_cancel(struct alarm *alarm);
ktime_t alarm_get_elapsed_realtime(void);
/* set rtc while preserving elapsed realtime */
int alarm_set_rtc(const struct timespec ts);
#endif
enum android_alarm_return_flags {
ANDROID_ALARM_RTC_WAKEUP_MASK = 1U << ANDROID_ALARM_RTC_WAKEUP,
ANDROID_ALARM_RTC_MASK = 1U << ANDROID_ALARM_RTC,
ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP_MASK =
1U << ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP,
ANDROID_ALARM_ELAPSED_REALTIME_MASK =
1U << ANDROID_ALARM_ELAPSED_REALTIME,
ANDROID_ALARM_SYSTEMTIME_MASK = 1U << ANDROID_ALARM_SYSTEMTIME,
ANDROID_ALARM_TIME_CHANGE_MASK = 1U << 16
};
/* Disable alarm */
#define ANDROID_ALARM_CLEAR(type) _IO('a', 0 | ((type) << 4))
/* Ack last alarm and wait for next */
#define ANDROID_ALARM_WAIT _IO('a', 1)
#define ALARM_IOW(c, type, size) _IOW('a', (c) | ((type) << 4), size)
/* Set alarm */
#define ANDROID_ALARM_SET(type) ALARM_IOW(2, type, struct timespec)
#define ANDROID_ALARM_SET_AND_WAIT(type) ALARM_IOW(3, type, struct timespec)
#define ANDROID_ALARM_GET_TIME(type) ALARM_IOW(4, type, struct timespec)
#define ANDROID_ALARM_SET_RTC _IOW('a', 5, struct timespec)
#define ANDROID_ALARM_BASE_CMD(cmd) (cmd & ~(_IOC(0, 0, 0xf0, 0)))
#define ANDROID_ALARM_IOCTL_TO_TYPE(cmd) (_IOC_NR(cmd) >> 4)
#endif
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