Merge tag 'jfs-5.19' of https://github.com/kleikamp/linux-shaggy
[linux-block.git] / include / linux / rtc.h
CommitLineData
b2441318 1/* SPDX-License-Identifier: GPL-2.0 */
1da177e4
LT
2/*
3 * Generic RTC interface.
4 * This version contains the part of the user interface to the Real Time Clock
5 * service. It is used with both the legacy mc146818 and also EFI
6 * Struct rtc_time and first 12 ioctl by Paul Gortmaker, 1996 - separated out
7 * from <linux/mc146818rtc.h> to this file for 2.4 kernels.
ab6a2d70 8 *
1da177e4
LT
9 * Copyright (C) 1999 Hewlett-Packard Co.
10 * Copyright (C) 1999 Stephane Eranian <eranian@hpl.hp.com>
11 */
12#ifndef _LINUX_RTC_H_
13#define _LINUX_RTC_H_
14
1da177e4 15
78d89ef4 16#include <linux/types.h>
4024ce5e 17#include <linux/interrupt.h>
697e5a47 18#include <linux/nvmem-provider.h>
607ca46e 19#include <uapi/linux/rtc.h>
4024ce5e 20
c58411e9 21extern int rtc_month_days(unsigned int month, unsigned int year);
8232212e 22extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year);
c58411e9 23extern int rtc_valid_tm(struct rtc_time *tm);
c2c11ae4 24extern time64_t rtc_tm_to_time64(struct rtc_time *tm);
25extern void rtc_time64_to_tm(time64_t time, struct rtc_time *tm);
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26ktime_t rtc_tm_to_ktime(struct rtc_time tm);
27struct rtc_time rtc_ktime_to_tm(ktime_t kt);
28
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29/*
30 * rtc_tm_sub - Return the difference in seconds.
31 */
32static inline time64_t rtc_tm_sub(struct rtc_time *lhs, struct rtc_time *rhs)
33{
34 return rtc_tm_to_time64(lhs) - rtc_tm_to_time64(rhs);
35}
36
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37#include <linux/device.h>
38#include <linux/seq_file.h>
39#include <linux/cdev.h>
40#include <linux/poll.h>
41#include <linux/mutex.h>
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42#include <linux/timerqueue.h>
43#include <linux/workqueue.h>
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44
45extern struct class *rtc_class;
46
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47/*
48 * For these RTC methods the device parameter is the physical device
49 * on whatever bus holds the hardware (I2C, Platform, SPI, etc), which
50 * was passed to rtc_device_register(). Its driver_data normally holds
51 * device state, including the rtc_device pointer for the RTC.
52 *
53 * Most of these methods are called with rtc_device.ops_lock held,
54 * through the rtc_*(struct rtc_device *, ...) calls.
55 *
56 * The (current) exceptions are mostly filesystem hooks:
57 * - the proc() hook for procfs
5ad31a57 58 */
0c86edc0 59struct rtc_class_ops {
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60 int (*ioctl)(struct device *, unsigned int, unsigned long);
61 int (*read_time)(struct device *, struct rtc_time *);
62 int (*set_time)(struct device *, struct rtc_time *);
63 int (*read_alarm)(struct device *, struct rtc_wkalrm *);
64 int (*set_alarm)(struct device *, struct rtc_wkalrm *);
65 int (*proc)(struct device *, struct seq_file *);
099e6576 66 int (*alarm_irq_enable)(struct device *, unsigned int enabled);
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67 int (*read_offset)(struct device *, long *offset);
68 int (*set_offset)(struct device *, long offset);
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69 int (*param_get)(struct device *, struct rtc_param *param);
70 int (*param_set)(struct device *, struct rtc_param *param);
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71};
72
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73struct rtc_device;
74
6610e089 75struct rtc_timer {
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76 struct timerqueue_node node;
77 ktime_t period;
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78 void (*func)(struct rtc_device *rtc);
79 struct rtc_device *rtc;
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80 int enabled;
81};
82
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83/* flags */
84#define RTC_DEV_BUSY 0
789c1093 85#define RTC_NO_CDEV 1
8853c202 86
1796dcce 87struct rtc_device {
cd966209 88 struct device dev;
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89 struct module *owner;
90
91 int id;
0c86edc0 92
ff8371ac 93 const struct rtc_class_ops *ops;
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94 struct mutex ops_lock;
95
0c86edc0 96 struct cdev char_dev;
8853c202 97 unsigned long flags;
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98
99 unsigned long irq_data;
100 spinlock_t irq_lock;
101 wait_queue_head_t irq_queue;
102 struct fasync_struct *async_queue;
103
0c86edc0 104 int irq_freq;
110d693d 105 int max_user_freq;
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106
107 struct timerqueue_head timerqueue;
108 struct rtc_timer aie_timer;
109 struct rtc_timer uie_rtctimer;
110 struct hrtimer pie_timer; /* sub second exp, so needs hrtimer */
111 int pie_enabled;
112 struct work_struct irqwork;
6e57b1d6 113
69eca258
TG
114 /*
115 * This offset specifies the update timing of the RTC.
116 *
117 * tsched t1 write(t2.tv_sec - 1sec)) t2 RTC increments seconds
118 *
119 * The offset defines how tsched is computed so that the write to
120 * the RTC (t2.tv_sec - 1sec) is correct versus the time required
121 * for the transport of the write and the time which the RTC needs
122 * to increment seconds the first time after the write (t2).
123 *
124 * For direct accessible RTCs tsched ~= t1 because the write time
125 * is negligible. For RTCs behind slow busses the transport time is
126 * significant and has to be taken into account.
127 *
128 * The time between the write (t1) and the first increment after
129 * the write (t2) is RTC specific. For a MC146818 RTC it's 500ms,
130 * for many others it's exactly 1 second. Consult the datasheet.
131 *
132 * The value of this offset is also used to calculate the to be
133 * written value (t2.tv_sec - 1sec) at tsched.
134 *
135 * The default value for this is NSEC_PER_SEC + 10 msec default
136 * transport time. The offset can be adjusted by drivers so the
137 * calculation for the to be written value at tsched becomes
138 * correct:
139 *
140 * newval = tsched + set_offset_nsec - NSEC_PER_SEC
141 * and (tsched + set_offset_nsec) % NSEC_PER_SEC == 0
0f295b06 142 */
69eca258 143 unsigned long set_offset_nsec;
0f295b06 144
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145 unsigned long features[BITS_TO_LONGS(RTC_FEATURE_CNT)];
146
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147 time64_t range_min;
148 timeu64_t range_max;
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BW
149 time64_t start_secs;
150 time64_t offset_secs;
151 bool set_start_time;
71db049e 152
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153#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
154 struct work_struct uie_task;
155 struct timer_list uie_timer;
156 /* Those fields are protected by rtc->irq_lock */
157 unsigned int oldsecs;
158 unsigned int uie_irq_active:1;
159 unsigned int stop_uie_polling:1;
160 unsigned int uie_task_active:1;
161 unsigned int uie_timer_active:1;
162#endif
0c86edc0 163};
cd966209 164#define to_rtc_device(d) container_of(d, struct rtc_device, dev)
0c86edc0 165
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AB
166#define rtc_lock(d) mutex_lock(&d->ops_lock)
167#define rtc_unlock(d) mutex_unlock(&d->ops_lock)
168
83bbc5ac 169/* useful timestamps */
f00eaa38 170#define RTC_TIMESTAMP_BEGIN_0000 -62167219200ULL /* 0000-01-01 00:00:00 */
d3062d1d 171#define RTC_TIMESTAMP_BEGIN_1900 -2208988800LL /* 1900-01-01 00:00:00 */
83bbc5ac 172#define RTC_TIMESTAMP_BEGIN_2000 946684800LL /* 2000-01-01 00:00:00 */
5ff404d1 173#define RTC_TIMESTAMP_END_2063 2966371199LL /* 2063-12-31 23:59:59 */
cbc943eb 174#define RTC_TIMESTAMP_END_2079 3471292799LL /* 2079-12-31 23:59:59 */
83bbc5ac 175#define RTC_TIMESTAMP_END_2099 4102444799LL /* 2099-12-31 23:59:59 */
8d6ac1ce 176#define RTC_TIMESTAMP_END_2199 7258118399LL /* 2199-12-31 23:59:59 */
beee05df 177#define RTC_TIMESTAMP_END_9999 253402300799LL /* 9999-12-31 23:59:59 */
83bbc5ac 178
6636a994
JH
179extern struct rtc_device *devm_rtc_device_register(struct device *dev,
180 const char *name,
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JH
181 const struct rtc_class_ops *ops,
182 struct module *owner);
3068a254 183struct rtc_device *devm_rtc_allocate_device(struct device *dev);
fdcfd854 184int __devm_rtc_register_device(struct module *owner, struct rtc_device *rtc);
0c86edc0 185
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DB
186extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
187extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
f44f7f96 188int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm);
ab6a2d70 189extern int rtc_read_alarm(struct rtc_device *rtc,
0c86edc0 190 struct rtc_wkalrm *alrm);
ab6a2d70 191extern int rtc_set_alarm(struct rtc_device *rtc,
0c86edc0 192 struct rtc_wkalrm *alrm);
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193extern int rtc_initialize_alarm(struct rtc_device *rtc,
194 struct rtc_wkalrm *alrm);
ab6a2d70 195extern void rtc_update_irq(struct rtc_device *rtc,
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196 unsigned long num, unsigned long events);
197
9f3b795a 198extern struct rtc_device *rtc_class_open(const char *name);
ab6a2d70 199extern void rtc_class_close(struct rtc_device *rtc);
0c86edc0 200
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AB
201extern int rtc_irq_set_state(struct rtc_device *rtc, int enabled);
202extern int rtc_irq_set_freq(struct rtc_device *rtc, int freq);
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203extern int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled);
204extern int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled);
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205extern int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc,
206 unsigned int enabled);
0c86edc0 207
456d66ec 208void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode);
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AB
209void rtc_aie_update_irq(struct rtc_device *rtc);
210void rtc_uie_update_irq(struct rtc_device *rtc);
6610e089 211enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer);
1da177e4 212
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AB
213void rtc_timer_init(struct rtc_timer *timer, void (*f)(struct rtc_device *r),
214 struct rtc_device *rtc);
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215int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer *timer,
216 ktime_t expires, ktime_t period);
73744a64 217void rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer *timer);
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218int rtc_read_offset(struct rtc_device *rtc, long *offset);
219int rtc_set_offset(struct rtc_device *rtc, long offset);
96c8f06a 220void rtc_timer_do_work(struct work_struct *work);
6610e089 221
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AM
222static inline bool is_leap_year(unsigned int year)
223{
224 return (!(year % 4) && (year % 100)) || !(year % 400);
225}
226
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227#define devm_rtc_register_device(device) \
228 __devm_rtc_register_device(THIS_MODULE, device)
3068a254 229
4c24e29e 230#ifdef CONFIG_RTC_HCTOSYS_DEVICE
d0ab4a4d
UKK
231extern int rtc_hctosys_ret;
232#else
233#define rtc_hctosys_ret -ENODEV
234#endif
235
fd5cd21d 236#ifdef CONFIG_RTC_NVMEM
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237int devm_rtc_nvmem_register(struct rtc_device *rtc,
238 struct nvmem_config *nvmem_config);
fd5cd21d 239#else
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BG
240static inline int devm_rtc_nvmem_register(struct rtc_device *rtc,
241 struct nvmem_config *nvmem_config)
fd5cd21d 242{
c59b3715 243 return 0;
fd5cd21d 244}
fd5cd21d
AB
245#endif
246
eb2bccb7
AB
247#ifdef CONFIG_RTC_INTF_SYSFS
248int rtc_add_group(struct rtc_device *rtc, const struct attribute_group *grp);
249int rtc_add_groups(struct rtc_device *rtc, const struct attribute_group **grps);
250#else
251static inline
252int rtc_add_group(struct rtc_device *rtc, const struct attribute_group *grp)
253{
254 return 0;
255}
256
257static inline
258int rtc_add_groups(struct rtc_device *rtc, const struct attribute_group **grps)
259{
260 return 0;
261}
262#endif
1da177e4 263#endif /* _LINUX_RTC_H_ */