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Diffstat (limited to 'include/linux/rtc.h')
| -rw-r--r-- | include/linux/rtc.h | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/include/linux/rtc.h b/include/linux/rtc.h new file mode 100644 index 000000000..1fd9c6a21 --- /dev/null +++ b/include/linux/rtc.h @@ -0,0 +1,263 @@ +/* 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 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; + 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); +} + +#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_ */ |