rtc.h

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/*
 * Generic RTC interface.
 * This version contains the part of the user interface to the Real Time Clock
 * service. It is used with both the legacy mc146818 and also  EFI
 * Struct rtc_time and first 12 ioctl by Paul Gortmaker, 1996 - separated out
 * from <linux/mc146818rtc.h> to this file for 2.4 kernels.
 *
 * Copyright (C) 1999 Hewlett-Packard Co.
 * Copyright (C) 1999 Stephane Eranian <[email protected]>
 */
#ifndef _LINUX_RTC_H_
#define _LINUX_RTC_H_


#include <linux/types.h>
#include <linux/interrupt.h>
#include <uapi/linux/rtc.h>

extern int rtc_month_days(unsigned int month, unsigned int year);
extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year);
extern int rtc_valid_tm(struct rtc_time *tm);
extern int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time);
extern void rtc_time_to_tm(unsigned long time, struct rtc_time *tm);
ktime_t rtc_tm_to_ktime(struct rtc_time tm);
struct rtc_time rtc_ktime_to_tm(ktime_t kt);


#include <linux/device.h>
#include <linux/seq_file.h>
#include <linux/cdev.h>
#include <linux/poll.h>
#include <linux/mutex.h>
#include <linux/timerqueue.h>
#include <linux/workqueue.h>

extern struct class *rtc_class;

/*
 * For these RTC methods the device parameter is the physical device
 * on whatever bus holds the hardware (I2C, Platform, SPI, etc), which
 * was passed to rtc_device_register().  Its driver_data normally holds
 * device state, including the rtc_device pointer for the RTC.
 *
 * Most of these methods are called with rtc_device.ops_lock held,
 * through the rtc_*(struct rtc_device *, ...) calls.
 *
 * The (current) exceptions are mostly filesystem hooks:
 *   - the proc() hook for procfs
 *   - non-ioctl() chardev hooks:  open(), release(), read_callback()
 *
 * REVISIT those periodic irq calls *do* have ops_lock when they're
 * issued through ioctl() ...
 */
struct rtc_class_ops {
    int (*open)(struct device *);
    void (*release)(struct device *);
    int (*ioctl)(struct device *, unsigned int, unsigned long);
    int (*read_time)(struct device *, struct rtc_time *);
    int (*set_time)(struct device *, struct rtc_time *);
    int (*read_alarm)(struct device *, struct rtc_wkalrm *);
    int (*set_alarm)(struct device *, struct rtc_wkalrm *);
    int (*proc)(struct device *, struct seq_file *);
    int (*set_mmss)(struct device *, unsigned long secs);
    int (*read_callback)(struct device *, int data);
    int (*alarm_irq_enable)(struct device *, unsigned int enabled);
};

#define RTC_DEVICE_NAME_SIZE 20
typedef struct rtc_task {
    void (*func)(void *private_data);
    void *private_data;
} rtc_task_t;


struct rtc_timer {
    struct rtc_task task;
    struct timerqueue_node node;
    ktime_t period;
    int enabled;
};


/* flags */
#define RTC_DEV_BUSY 0

struct rtc_device
{
    struct device dev;
    struct module *owner;

    int id;
    char name[RTC_DEVICE_NAME_SIZE];

    const struct rtc_class_ops *ops;
    struct mutex ops_lock;

    struct cdev char_dev;
    unsigned long flags;

    unsigned long irq_data;
    spinlock_t irq_lock;
    wait_queue_head_t irq_queue;
    struct fasync_struct *async_queue;

    struct rtc_task *irq_task;
    spinlock_t irq_task_lock;
    int irq_freq;
    int max_user_freq;

    struct timerqueue_head timerqueue;
    struct rtc_timer aie_timer;
    struct rtc_timer uie_rtctimer;
    struct hrtimer pie_timer; /* sub second exp, so needs hrtimer */
    int pie_enabled;
    struct work_struct irqwork;
    /* Some hardware can't support UIE mode */
    int uie_unsupported;

#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
    struct work_struct uie_task;
    struct timer_list uie_timer;
    /* Those fields are protected by rtc->irq_lock */
    unsigned int oldsecs;
    unsigned int uie_irq_active:1;
    unsigned int stop_uie_polling:1;
    unsigned int uie_task_active:1;
    unsigned int uie_timer_active:1;
#endif
};
#define to_rtc_device(d) container_of(d, struct rtc_device, dev)

extern struct rtc_device *rtc_device_register(const char *name,
                    struct device *dev,
                    const struct rtc_class_ops *ops,
                    struct module *owner);
extern void rtc_device_unregister(struct rtc_device *rtc);

extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
extern int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs);
int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm);
extern int rtc_read_alarm(struct rtc_device *rtc,
            struct rtc_wkalrm *alrm);
extern int rtc_set_alarm(struct rtc_device *rtc,
                struct rtc_wkalrm *alrm);
extern int rtc_initialize_alarm(struct rtc_device *rtc,
                struct rtc_wkalrm *alrm);
extern void rtc_update_irq(struct rtc_device *rtc,
            unsigned long num, unsigned long events);

extern struct rtc_device *rtc_class_open(char *name);
extern void rtc_class_close(struct rtc_device *rtc);

extern int rtc_irq_register(struct rtc_device *rtc,
                struct rtc_task *task);
extern void rtc_irq_unregister(struct rtc_device *rtc,
                struct rtc_task *task);
extern int rtc_irq_set_state(struct rtc_device *rtc,
                struct rtc_task *task, int enabled);
extern int rtc_irq_set_freq(struct rtc_device *rtc,
                struct rtc_task *task, int freq);
extern int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled);
extern int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled);
extern int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc,
                        unsigned int enabled);

void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode);
void rtc_aie_update_irq(void *private);
void rtc_uie_update_irq(void *private);
enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer);

int rtc_register(rtc_task_t *task);
int rtc_unregister(rtc_task_t *task);
int rtc_control(rtc_task_t *t, unsigned int cmd, unsigned long arg);

void rtc_timer_init(struct rtc_timer *timer, void (*f)(void* p), void* data);
int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer* timer,
            ktime_t expires, ktime_t period);
int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer* timer);
void rtc_timer_do_work(struct work_struct *work);

static inline bool is_leap_year(unsigned int year)
{
    return (!(year % 4) && (year % 100)) || !(year % 400);
}

#ifdef CONFIG_RTC_HCTOSYS_DEVICE
extern int rtc_hctosys_ret;
#else
#define rtc_hctosys_ret -ENODEV
#endif

#endif /* _LINUX_RTC_H_ */