/* 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 <linux/mc146818rtc.h> to this file for 2.4 kernels. * * Copyright (C) 1999 Hewlett-Packard Co. * Copyright (C) 1999 Stephane Eranian <eranian@hpl.hp.com> */ #ifndef _LINUX_RTC_H_ #define _LINUX_RTC_H_ #include <linux/types.h> #include <linux/interrupt.h> #include <linux/nvmem-provider.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 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); } #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 const 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 */ 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 (*alarm_irq_enable)(struct device *, unsigned int enabled); int (*read_offset)(struct device *, long *offset); int (*set_offset)(struct device *, long offset); int (*param_get)(struct device *, struct rtc_param *param); int (*param_set)(struct device *, struct rtc_param *param); }; struct rtc_device; struct rtc_timer { struct timerqueue_node node; ktime_t period; void (*func)(struct rtc_device *rtc); struct rtc_device *rtc; int enabled; }; /* flags */ #define RTC_DEV_BUSY 0 #define RTC_NO_CDEV 1 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; /* * This offset specifies the update timing of the RTC. * * tsched t1 write(t2.tv_sec - 1sec)) t2 RTC increments seconds * * The offset defines how tsched is computed so that the write to * the RTC (t2.tv_sec - 1sec) is correct versus the time required * for the transport of the write and the time which the RTC needs * to increment seconds the first time after the write (t2). * * For direct accessible RTCs tsched ~= t1 because the write time * is negligible. For RTCs behind slow busses the transport time is * significant and has to be taken into account. * * The time between the write (t1) and the first increment after * the write (t2) is RTC specific. For a MC146818 RTC it's 500ms, * for many others it's exactly 1 second. Consult the datasheet. * * The value of this offset is also used to calculate the to be * written value (t2.tv_sec - 1sec) at tsched. * * The default value for this is NSEC_PER_SEC + 10 msec default * transport time. The offset can be adjusted by drivers so the * calculation for the to be written value at tsched becomes * correct: * * newval = tsched + set_offset_nsec - NSEC_PER_SEC * and (tsched + set_offset_nsec) % NSEC_PER_SEC == 0 */ unsigned long set_offset_nsec; unsigned long features[BITS_TO_LONGS(RTC_FEATURE_CNT)]; time64_t range_min; timeu64_t range_max; timeu64_t alarm_offset_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) #define rtc_lock(d) mutex_lock(&d->ops_lock) #define rtc_unlock(d) mutex_unlock(&d->ops_lock) /* useful timestamps */ #define RTC_TIMESTAMP_BEGIN_0000 -62167219200ULL /* 0000-01-01 00:00:00 */ #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_2063 2966371199LL /* 2063-12-31 23:59:59 */ #define RTC_TIMESTAMP_END_2079 3471292799LL /* 2079-12-31 23:59:59 */ #define RTC_TIMESTAMP_END_2099 4102444799LL /* 2099-12-31 23:59:59 */ #define RTC_TIMESTAMP_END_2199 7258118399LL /* 2199-12-31 23:59:59 */ #define RTC_TIMESTAMP_END_9999 253402300799LL /* 9999-12-31 23:59:59 */ 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 __devm_rtc_register_device(struct module *owner, 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); 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(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(struct rtc_device *rtc); void rtc_uie_update_irq(struct rtc_device *rtc); enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer); void rtc_timer_init(struct rtc_timer *timer, void (*f)(struct rtc_device *r), struct rtc_device *rtc); 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); } /** * rtc_bound_alarmtime() - Return alarm time bound by rtc limit * @rtc: Pointer to rtc device structure * @requested: Requested alarm timeout * * Return: Alarm timeout bound by maximum alarm time supported by rtc. */ static inline ktime_t rtc_bound_alarmtime(struct rtc_device *rtc, ktime_t requested) { if (rtc->alarm_offset_max && rtc->alarm_offset_max * MSEC_PER_SEC < ktime_to_ms(requested)) return ms_to_ktime(rtc->alarm_offset_max * MSEC_PER_SEC); return requested; } #define devm_rtc_register_device(device) \ __devm_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 devm_rtc_nvmem_register(struct rtc_device *rtc, struct nvmem_config *nvmem_config); #else static inline int devm_rtc_nvmem_register(struct rtc_device *rtc, struct nvmem_config *nvmem_config) { return 0; } #endif #ifdef CONFIG_RTC_INTF_SYSFS int rtc_add_group(struct rtc_device *rtc, const struct attribute_group *grp); int rtc_add_groups(struct rtc_device *rtc, const struct attribute_group **grps); #else static inline int rtc_add_group(struct rtc_device *rtc, const struct attribute_group *grp) { return 0; } static inline int rtc_add_groups(struct rtc_device *rtc, const struct attribute_group **grps) { return 0; } #endif #endif /* _LINUX_RTC_H_ */