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 <linux/nvmem-provider.h>
  18#include <uapi/linux/rtc.h>
  19
  20extern int rtc_month_days(unsigned int month, unsigned int year);
  21extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year);
  22extern int rtc_valid_tm(struct rtc_time *tm);
  23extern time64_t rtc_tm_to_time64(struct rtc_time *tm);
  24extern void rtc_time64_to_tm(time64_t time, struct rtc_time *tm);
  25ktime_t rtc_tm_to_ktime(struct rtc_time tm);
  26struct rtc_time rtc_ktime_to_tm(ktime_t kt);
  27
  28/*
  29 * rtc_tm_sub - Return the difference in seconds.
  30 */
  31static inline time64_t rtc_tm_sub(struct rtc_time *lhs, struct rtc_time *rhs)
  32{
  33        return rtc_tm_to_time64(lhs) - rtc_tm_to_time64(rhs);
  34}
  35
  36static inline void rtc_time_to_tm(unsigned long time, struct rtc_time *tm)
  37{
  38        rtc_time64_to_tm(time, tm);
  39}
  40
  41static inline int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time)
  42{
  43        *time = rtc_tm_to_time64(tm);
  44
  45        return 0;
  46}
  47
  48#include <linux/device.h>
  49#include <linux/seq_file.h>
  50#include <linux/cdev.h>
  51#include <linux/poll.h>
  52#include <linux/mutex.h>
  53#include <linux/timerqueue.h>
  54#include <linux/workqueue.h>
  55
  56extern struct class *rtc_class;
  57
  58/*
  59 * For these RTC methods the device parameter is the physical device
  60 * on whatever bus holds the hardware (I2C, Platform, SPI, etc), which
  61 * was passed to rtc_device_register().  Its driver_data normally holds
  62 * device state, including the rtc_device pointer for the RTC.
  63 *
  64 * Most of these methods are called with rtc_device.ops_lock held,
  65 * through the rtc_*(struct rtc_device *, ...) calls.
  66 *
  67 * The (current) exceptions are mostly filesystem hooks:
  68 *   - the proc() hook for procfs
  69 *   - non-ioctl() chardev hooks:  open(), release(), read_callback()
  70 *
  71 * REVISIT those periodic irq calls *do* have ops_lock when they're
  72 * issued through ioctl() ...
  73 */
  74struct rtc_class_ops {
  75        int (*open)(struct device *);
  76        void (*release)(struct device *);
  77        int (*ioctl)(struct device *, unsigned int, unsigned long);
  78        int (*read_time)(struct device *, struct rtc_time *);
  79        int (*set_time)(struct device *, struct rtc_time *);
  80        int (*read_alarm)(struct device *, struct rtc_wkalrm *);
  81        int (*set_alarm)(struct device *, struct rtc_wkalrm *);
  82        int (*proc)(struct device *, struct seq_file *);
  83        int (*set_mmss64)(struct device *, time64_t secs);
  84        int (*set_mmss)(struct device *, unsigned long secs);
  85        int (*read_callback)(struct device *, int data);
  86        int (*alarm_irq_enable)(struct device *, unsigned int enabled);
  87        int (*read_offset)(struct device *, long *offset);
  88        int (*set_offset)(struct device *, long offset);
  89};
  90
  91#define RTC_DEVICE_NAME_SIZE 20
  92typedef struct rtc_task {
  93        void (*func)(void *private_data);
  94        void *private_data;
  95} rtc_task_t;
  96
  97
  98struct rtc_timer {
  99        struct rtc_task task;
 100        struct timerqueue_node node;
 101        ktime_t period;
 102        int enabled;
 103};
 104
 105
 106/* flags */
 107#define RTC_DEV_BUSY 0
 108
 109struct rtc_device {
 110        struct device dev;
 111        struct module *owner;
 112
 113        int id;
 114
 115        const struct rtc_class_ops *ops;
 116        struct mutex ops_lock;
 117
 118        struct cdev char_dev;
 119        unsigned long flags;
 120
 121        unsigned long irq_data;
 122        spinlock_t irq_lock;
 123        wait_queue_head_t irq_queue;
 124        struct fasync_struct *async_queue;
 125
 126        struct rtc_task *irq_task;
 127        spinlock_t irq_task_lock;
 128        int irq_freq;
 129        int max_user_freq;
 130
 131        struct timerqueue_head timerqueue;
 132        struct rtc_timer aie_timer;
 133        struct rtc_timer uie_rtctimer;
 134        struct hrtimer pie_timer; /* sub second exp, so needs hrtimer */
 135        int pie_enabled;
 136        struct work_struct irqwork;
 137        /* Some hardware can't support UIE mode */
 138        int uie_unsupported;
 139
 140        bool registered;
 141
 142        struct nvmem_config *nvmem_config;
 143        struct nvmem_device *nvmem;
 144        /* Old ABI support */
 145        bool nvram_old_abi;
 146        struct bin_attribute *nvram;
 147
 148#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
 149        struct work_struct uie_task;
 150        struct timer_list uie_timer;
 151        /* Those fields are protected by rtc->irq_lock */
 152        unsigned int oldsecs;
 153        unsigned int uie_irq_active:1;
 154        unsigned int stop_uie_polling:1;
 155        unsigned int uie_task_active:1;
 156        unsigned int uie_timer_active:1;
 157#endif
 158};
 159#define to_rtc_device(d) container_of(d, struct rtc_device, dev)
 160
 161extern struct rtc_device *rtc_device_register(const char *name,
 162                                        struct device *dev,
 163                                        const struct rtc_class_ops *ops,
 164                                        struct module *owner);
 165extern struct rtc_device *devm_rtc_device_register(struct device *dev,
 166                                        const char *name,
 167                                        const struct rtc_class_ops *ops,
 168                                        struct module *owner);
 169struct rtc_device *devm_rtc_allocate_device(struct device *dev);
 170int __rtc_register_device(struct module *owner, struct rtc_device *rtc);
 171extern void rtc_device_unregister(struct rtc_device *rtc);
 172extern void devm_rtc_device_unregister(struct device *dev,
 173                                        struct rtc_device *rtc);
 174
 175extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
 176extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
 177extern int rtc_set_ntp_time(struct timespec64 now);
 178int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm);
 179extern int rtc_read_alarm(struct rtc_device *rtc,
 180                        struct rtc_wkalrm *alrm);
 181extern int rtc_set_alarm(struct rtc_device *rtc,
 182                                struct rtc_wkalrm *alrm);
 183extern int rtc_initialize_alarm(struct rtc_device *rtc,
 184                                struct rtc_wkalrm *alrm);
 185extern void rtc_update_irq(struct rtc_device *rtc,
 186                        unsigned long num, unsigned long events);
 187
 188extern struct rtc_device *rtc_class_open(const char *name);
 189extern void rtc_class_close(struct rtc_device *rtc);
 190
 191extern int rtc_irq_register(struct rtc_device *rtc,
 192                                struct rtc_task *task);
 193extern void rtc_irq_unregister(struct rtc_device *rtc,
 194                                struct rtc_task *task);
 195extern int rtc_irq_set_state(struct rtc_device *rtc,
 196                                struct rtc_task *task, int enabled);
 197extern int rtc_irq_set_freq(struct rtc_device *rtc,
 198                                struct rtc_task *task, int freq);
 199extern int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled);
 200extern int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled);
 201extern int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc,
 202                                                unsigned int enabled);
 203
 204void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode);
 205void rtc_aie_update_irq(void *private);
 206void rtc_uie_update_irq(void *private);
 207enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer);
 208
 209int rtc_register(rtc_task_t *task);
 210int rtc_unregister(rtc_task_t *task);
 211int rtc_control(rtc_task_t *t, unsigned int cmd, unsigned long arg);
 212
 213void rtc_timer_init(struct rtc_timer *timer, void (*f)(void *p), void *data);
 214int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer *timer,
 215                    ktime_t expires, ktime_t period);
 216void rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer *timer);
 217int rtc_read_offset(struct rtc_device *rtc, long *offset);
 218int rtc_set_offset(struct rtc_device *rtc, long offset);
 219void rtc_timer_do_work(struct work_struct *work);
 220
 221static inline bool is_leap_year(unsigned int year)
 222{
 223        return (!(year % 4) && (year % 100)) || !(year % 400);
 224}
 225
 226#define rtc_register_device(device) \
 227        __rtc_register_device(THIS_MODULE, device)
 228
 229#ifdef CONFIG_RTC_HCTOSYS_DEVICE
 230extern int rtc_hctosys_ret;
 231#else
 232#define rtc_hctosys_ret -ENODEV
 233#endif
 234
 235#endif /* _LINUX_RTC_H_ */
 236