/* SPDX-License-Identifier: GPL-2.0 */ /* * 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 to this file for 2.4 kernels. * * Copyright (C) 1999 Hewlett-Packard Co. * Copyright (C) 1999 Stephane Eranian */ #ifndef _LINUX_RTC_H_ #define _LINUX_RTC_H_ #include #include #include #include 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 time64_t rtc_tm_to_time64(struct rtc_time *tm); extern void rtc_time64_to_tm(time64_t 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); /* * rtc_tm_sub - Return the difference in seconds. */ static inline time64_t rtc_tm_sub(struct rtc_time *lhs, struct rtc_time *rhs) { return rtc_tm_to_time64(lhs) - rtc_tm_to_time64(rhs); } static inline void rtc_time_to_tm(unsigned long time, struct rtc_time *tm) { rtc_time64_to_tm(time, tm); } static inline int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time) { *time = rtc_tm_to_time64(tm); return 0; } #include #include #include #include #include #include #include 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 (*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_mmss64)(struct device *, time64_t secs); int (*set_mmss)(struct device *, unsigned long secs); int (*read_callback)(struct device *, int data); int (*alarm_irq_enable)(struct device *, unsigned int enabled); int (*read_offset)(struct device *, long *offset); int (*set_offset)(struct device *, long offset); }; struct rtc_timer { struct timerqueue_node node; ktime_t period; void (*func)(void *private_data); void *private_data; int enabled; }; /* flags */ #define RTC_DEV_BUSY 0 struct rtc_device { struct device dev; struct module *owner; int id; 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; 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; /* Number of nsec it takes to set the RTC clock. This influences when * the set ops are called. An offset: * - of 0.5 s will call RTC set for wall clock time 10.0 s at 9.5 s * - of 1.5 s will call RTC set for wall clock time 10.0 s at 8.5 s * - of -0.5 s will call RTC set for wall clock time 10.0 s at 10.5 s */ long set_offset_nsec; bool registered; struct nvmem_device *nvmem; /* Old ABI support */ bool nvram_old_abi; struct bin_attribute *nvram; time64_t range_min; timeu64_t range_max; time64_t start_secs; time64_t offset_secs; bool set_start_time; #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) /* useful timestamps */ #define RTC_TIMESTAMP_BEGIN_1900 -2208988800LL /* 1900-01-01 00:00:00 */ #define RTC_TIMESTAMP_BEGIN_2000 946684800LL /* 2000-01-01 00:00:00 */ #define RTC_TIMESTAMP_END_2099 4102444799LL /* 2099-12-31 23:59:59 */ extern struct rtc_device *rtc_device_register(const char *name, struct device *dev, const struct rtc_class_ops *ops, struct module *owner); extern struct rtc_device *devm_rtc_device_register(struct device *dev, const char *name, const struct rtc_class_ops *ops, struct module *owner); struct rtc_device *devm_rtc_allocate_device(struct device *dev); int __rtc_register_device(struct module *owner, struct rtc_device *rtc); extern void rtc_device_unregister(struct rtc_device *rtc); extern void devm_rtc_device_unregister(struct device *dev, 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_ntp_time(struct timespec64 now, unsigned long *target_nsec); 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_set_alarm_poweron(struct rtc_device *rtc, struct rtc_wkalrm *alarm); 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(const char *name); extern void rtc_class_close(struct rtc_device *rtc); extern int rtc_irq_set_state(struct rtc_device *rtc, int enabled); extern int rtc_irq_set_freq(struct rtc_device *rtc, 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); 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); void rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer *timer); int rtc_read_offset(struct rtc_device *rtc, long *offset); int rtc_set_offset(struct rtc_device *rtc, long offset); 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); } /* Determine if we can call to driver to set the time. Drivers can only be * called to set a second aligned time value, and the field set_offset_nsec * specifies how far away from the second aligned time to call the driver. * * This also computes 'to_set' which is the time we are trying to set, and has * a zero in tv_nsecs, such that: * to_set - set_delay_nsec == now +/- FUZZ * */ static inline bool rtc_tv_nsec_ok(s64 set_offset_nsec, struct timespec64 *to_set, const struct timespec64 *now) { /* Allowed error in tv_nsec, arbitarily set to 5 jiffies in ns. */ const unsigned long TIME_SET_NSEC_FUZZ = TICK_NSEC * 5; struct timespec64 delay = {.tv_sec = 0, .tv_nsec = set_offset_nsec}; *to_set = timespec64_add(*now, delay); if (to_set->tv_nsec < TIME_SET_NSEC_FUZZ) { to_set->tv_nsec = 0; return true; } if (to_set->tv_nsec > NSEC_PER_SEC - TIME_SET_NSEC_FUZZ) { to_set->tv_sec++; to_set->tv_nsec = 0; return true; } return false; } #define rtc_register_device(device) \ __rtc_register_device(THIS_MODULE, device) #ifdef CONFIG_RTC_HCTOSYS_DEVICE extern int rtc_hctosys_ret; #else #define rtc_hctosys_ret -ENODEV #endif #ifdef CONFIG_RTC_NVMEM int rtc_nvmem_register(struct rtc_device *rtc, struct nvmem_config *nvmem_config); void rtc_nvmem_unregister(struct rtc_device *rtc); #else static inline int rtc_nvmem_register(struct rtc_device *rtc, struct nvmem_config *nvmem_config) { return 0; } static inline void rtc_nvmem_unregister(struct rtc_device *rtc) {} #endif #endif /* _LINUX_RTC_H_ */