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