LXR linux/include/linux/rtc.h

   1/*
   2 * Generic RTC interface.
   3 * This version contains the part of the user interface to the Real Time Clock
   4 * service. It is used with both the legacy mc146818 and also  EFI
   5 * Struct rtc_time and first 12 ioctl by Paul Gortmaker, 1996 - separated out
   6 * from <linux/mc146818rtc.h> to this file for 2.4 kernels.
   7 *
   8 * Copyright (C) 1999 Hewlett-Packard Co.
   9 * Copyright (C) 1999 Stephane Eranian <eranian@hpl.hp.com>
  10 */
  11#ifndef _LINUX_RTC_H_
  12#define _LINUX_RTC_H_
  13
  14
  15#include <linux/types.h>
  16#include <linux/interrupt.h>
  17#include <uapi/linux/rtc.h>
  18
  19extern int rtc_month_days(unsigned int month, unsigned int year);
  20extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year);
  21extern int rtc_valid_tm(struct rtc_time *tm);
  22extern time64_t rtc_tm_to_time64(struct rtc_time *tm);
  23extern void rtc_time64_to_tm(time64_t time, struct rtc_time *tm);
  24ktime_t rtc_tm_to_ktime(struct rtc_time tm);
  25struct rtc_time rtc_ktime_to_tm(ktime_t kt);
  26
  27/*
  28 * rtc_tm_sub - Return the difference in seconds.
  29 */
  30static inline time64_t rtc_tm_sub(struct rtc_time *lhs, struct rtc_time *rhs)
  31{
  32        return rtc_tm_to_time64(lhs) - rtc_tm_to_time64(rhs);
  33}
  34
  35/**
  36 * Deprecated. Use rtc_time64_to_tm().
  37 */
  38static inline void rtc_time_to_tm(unsigned long time, struct rtc_time *tm)
  39{
  40        rtc_time64_to_tm(time, tm);
  41}
  42
  43/**
  44 * Deprecated. Use rtc_tm_to_time64().
  45 */
  46static inline int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time)
  47{
  48        *time = rtc_tm_to_time64(tm);
  49
  50        return 0;
  51}
  52
  53#include <linux/device.h>
  54#include <linux/seq_file.h>
  55#include <linux/cdev.h>
  56#include <linux/poll.h>
  57#include <linux/mutex.h>
  58#include <linux/timerqueue.h>
  59#include <linux/workqueue.h>
  60
  61extern struct class *rtc_class;
  62
  63/*
  64 * For these RTC methods the device parameter is the physical device
  65 * on whatever bus holds the hardware (I2C, Platform, SPI, etc), which
  66 * was passed to rtc_device_register().  Its driver_data normally holds
  67 * device state, including the rtc_device pointer for the RTC.
  68 *
  69 * Most of these methods are called with rtc_device.ops_lock held,
  70 * through the rtc_*(struct rtc_device *, ...) calls.
  71 *
  72 * The (current) exceptions are mostly filesystem hooks:
  73 *   - the proc() hook for procfs
  74 *   - non-ioctl() chardev hooks:  open(), release(), read_callback()
  75 *
  76 * REVISIT those periodic irq calls *do* have ops_lock when they're
  77 * issued through ioctl() ...
  78 */
  79struct rtc_class_ops {
  80        int (*open)(struct device *);
  81        void (*release)(struct device *);
  82        int (*ioctl)(struct device *, unsigned int, unsigned long);
  83        int (*read_time)(struct device *, struct rtc_time *);
  84        int (*set_time)(struct device *, struct rtc_time *);
  85        int (*read_alarm)(struct device *, struct rtc_wkalrm *);
  86        int (*set_alarm)(struct device *, struct rtc_wkalrm *);
  87        int (*proc)(struct device *, struct seq_file *);
  88        int (*set_mmss64)(struct device *, time64_t secs);
  89        int (*set_mmss)(struct device *, unsigned long secs);
  90        int (*read_callback)(struct device *, int data);
  91        int (*alarm_irq_enable)(struct device *, unsigned int enabled);
  92};
  93
  94#define RTC_DEVICE_NAME_SIZE 20
  95typedef struct rtc_task {
  96        void (*func)(void *private_data);
  97        void *private_data;
  98} rtc_task_t;
  99
 100
 101struct rtc_timer {
 102        struct rtc_task task;
 103        struct timerqueue_node node;
 104        ktime_t period;
 105        int enabled;
 106};
 107
 108
 109/* flags */
 110#define RTC_DEV_BUSY 0
 111
 112struct rtc_device {
 113        struct device dev;
 114        struct module *owner;
 115
 116        int id;
 117        char name[RTC_DEVICE_NAME_SIZE];
 118
 119        const struct rtc_class_ops *ops;
 120        struct mutex ops_lock;
 121
 122        struct cdev char_dev;
 123        unsigned long flags;
 124
 125        unsigned long irq_data;
 126        spinlock_t irq_lock;
 127        wait_queue_head_t irq_queue;
 128        struct fasync_struct *async_queue;
 129
 130        struct rtc_task *irq_task;
 131        spinlock_t irq_task_lock;
 132        int irq_freq;
 133        int max_user_freq;
 134
 135        struct timerqueue_head timerqueue;
 136        struct rtc_timer aie_timer;
 137        struct rtc_timer uie_rtctimer;
 138        struct hrtimer pie_timer; /* sub second exp, so needs hrtimer */
 139        int pie_enabled;
 140        struct work_struct irqwork;
 141        /* Some hardware can't support UIE mode */
 142        int uie_unsupported;
 143
 144#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
 145        struct work_struct uie_task;
 146        struct timer_list uie_timer;
 147        /* Those fields are protected by rtc->irq_lock */
 148        unsigned int oldsecs;
 149        unsigned int uie_irq_active:1;
 150        unsigned int stop_uie_polling:1;
 151        unsigned int uie_task_active:1;
 152        unsigned int uie_timer_active:1;
 153#endif
 154};
 155#define to_rtc_device(d) container_of(d, struct rtc_device, dev)
 156
 157extern struct rtc_device *rtc_device_register(const char *name,
 158                                        struct device *dev,
 159                                        const struct rtc_class_ops *ops,
 160                                        struct module *owner);
 161extern struct rtc_device *devm_rtc_device_register(struct device *dev,
 162                                        const char *name,
 163                                        const struct rtc_class_ops *ops,
 164                                        struct module *owner);
 165extern void rtc_device_unregister(struct rtc_device *rtc);
 166extern void devm_rtc_device_unregister(struct device *dev,
 167                                        struct rtc_device *rtc);
 168
 169extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
 170extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
 171extern int rtc_set_ntp_time(struct timespec64 now);
 172int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm);
 173extern int rtc_read_alarm(struct rtc_device *rtc,
 174                        struct rtc_wkalrm *alrm);
 175extern int rtc_set_alarm(struct rtc_device *rtc,
 176                                struct rtc_wkalrm *alrm);
 177extern int rtc_initialize_alarm(struct rtc_device *rtc,
 178                                struct rtc_wkalrm *alrm);
 179extern void rtc_update_irq(struct rtc_device *rtc,
 180                        unsigned long num, unsigned long events);
 181
 182extern struct rtc_device *rtc_class_open(const char *name);
 183extern void rtc_class_close(struct rtc_device *rtc);
 184
 185extern int rtc_irq_register(struct rtc_device *rtc,
 186                                struct rtc_task *task);
 187extern void rtc_irq_unregister(struct rtc_device *rtc,
 188                                struct rtc_task *task);
 189extern int rtc_irq_set_state(struct rtc_device *rtc,
 190                                struct rtc_task *task, int enabled);
 191extern int rtc_irq_set_freq(struct rtc_device *rtc,
 192                                struct rtc_task *task, int freq);
 193extern int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled);
 194extern int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled);
 195extern int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc,
 196                                                unsigned int enabled);
 197
 198void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode);
 199void rtc_aie_update_irq(void *private);
 200void rtc_uie_update_irq(void *private);
 201enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer);
 202
 203int rtc_register(rtc_task_t *task);
 204int rtc_unregister(rtc_task_t *task);
 205int rtc_control(rtc_task_t *t, unsigned int cmd, unsigned long arg);
 206
 207void rtc_timer_init(struct rtc_timer *timer, void (*f)(void *p), void *data);
 208int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer *timer,
 209                    ktime_t expires, ktime_t period);
 210void rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer *timer);
 211void rtc_timer_do_work(struct work_struct *work);
 212
 213static inline bool is_leap_year(unsigned int year)
 214{
 215        return (!(year % 4) && (year % 100)) || !(year % 400);
 216}
 217
 218#ifdef CONFIG_RTC_HCTOSYS_DEVICE
 219extern int rtc_hctosys_ret;
 220#else
 221#define rtc_hctosys_ret -ENODEV
 222#endif
 223
 224#endif /* _LINUX_RTC_H_ */
 225