xref: /openbmc/linux/include/linux/rtc.h (revision 94cdda6b)
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 <uapi/linux/rtc.h>
18 
19 extern int rtc_month_days(unsigned int month, unsigned int year);
20 extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year);
21 extern int rtc_valid_tm(struct rtc_time *tm);
22 extern time64_t rtc_tm_to_time64(struct rtc_time *tm);
23 extern void rtc_time64_to_tm(time64_t time, struct rtc_time *tm);
24 ktime_t rtc_tm_to_ktime(struct rtc_time tm);
25 struct rtc_time rtc_ktime_to_tm(ktime_t kt);
26 
27 /**
28  * Deprecated. Use rtc_time64_to_tm().
29  */
30 static inline void rtc_time_to_tm(unsigned long time, struct rtc_time *tm)
31 {
32 	rtc_time64_to_tm(time, tm);
33 }
34 
35 /**
36  * Deprecated. Use rtc_tm_to_time64().
37  */
38 static inline int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time)
39 {
40 	*time = rtc_tm_to_time64(tm);
41 
42 	return 0;
43 }
44 
45 #include <linux/device.h>
46 #include <linux/seq_file.h>
47 #include <linux/cdev.h>
48 #include <linux/poll.h>
49 #include <linux/mutex.h>
50 #include <linux/timerqueue.h>
51 #include <linux/workqueue.h>
52 
53 extern struct class *rtc_class;
54 
55 /*
56  * For these RTC methods the device parameter is the physical device
57  * on whatever bus holds the hardware (I2C, Platform, SPI, etc), which
58  * was passed to rtc_device_register().  Its driver_data normally holds
59  * device state, including the rtc_device pointer for the RTC.
60  *
61  * Most of these methods are called with rtc_device.ops_lock held,
62  * through the rtc_*(struct rtc_device *, ...) calls.
63  *
64  * The (current) exceptions are mostly filesystem hooks:
65  *   - the proc() hook for procfs
66  *   - non-ioctl() chardev hooks:  open(), release(), read_callback()
67  *
68  * REVISIT those periodic irq calls *do* have ops_lock when they're
69  * issued through ioctl() ...
70  */
71 struct rtc_class_ops {
72 	int (*open)(struct device *);
73 	void (*release)(struct device *);
74 	int (*ioctl)(struct device *, unsigned int, unsigned long);
75 	int (*read_time)(struct device *, struct rtc_time *);
76 	int (*set_time)(struct device *, struct rtc_time *);
77 	int (*read_alarm)(struct device *, struct rtc_wkalrm *);
78 	int (*set_alarm)(struct device *, struct rtc_wkalrm *);
79 	int (*proc)(struct device *, struct seq_file *);
80 	int (*set_mmss64)(struct device *, time64_t secs);
81 	int (*set_mmss)(struct device *, unsigned long secs);
82 	int (*read_callback)(struct device *, int data);
83 	int (*alarm_irq_enable)(struct device *, unsigned int enabled);
84 };
85 
86 #define RTC_DEVICE_NAME_SIZE 20
87 typedef struct rtc_task {
88 	void (*func)(void *private_data);
89 	void *private_data;
90 } rtc_task_t;
91 
92 
93 struct rtc_timer {
94 	struct rtc_task	task;
95 	struct timerqueue_node node;
96 	ktime_t period;
97 	int enabled;
98 };
99 
100 
101 /* flags */
102 #define RTC_DEV_BUSY 0
103 
104 struct rtc_device
105 {
106 	struct device dev;
107 	struct module *owner;
108 
109 	int id;
110 	char name[RTC_DEVICE_NAME_SIZE];
111 
112 	const struct rtc_class_ops *ops;
113 	struct mutex ops_lock;
114 
115 	struct cdev char_dev;
116 	unsigned long flags;
117 
118 	unsigned long irq_data;
119 	spinlock_t irq_lock;
120 	wait_queue_head_t irq_queue;
121 	struct fasync_struct *async_queue;
122 
123 	struct rtc_task *irq_task;
124 	spinlock_t irq_task_lock;
125 	int irq_freq;
126 	int max_user_freq;
127 
128 	struct timerqueue_head timerqueue;
129 	struct rtc_timer aie_timer;
130 	struct rtc_timer uie_rtctimer;
131 	struct hrtimer pie_timer; /* sub second exp, so needs hrtimer */
132 	int pie_enabled;
133 	struct work_struct irqwork;
134 	/* Some hardware can't support UIE mode */
135 	int uie_unsupported;
136 
137 #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
138 	struct work_struct uie_task;
139 	struct timer_list uie_timer;
140 	/* Those fields are protected by rtc->irq_lock */
141 	unsigned int oldsecs;
142 	unsigned int uie_irq_active:1;
143 	unsigned int stop_uie_polling:1;
144 	unsigned int uie_task_active:1;
145 	unsigned int uie_timer_active:1;
146 #endif
147 };
148 #define to_rtc_device(d) container_of(d, struct rtc_device, dev)
149 
150 extern struct rtc_device *rtc_device_register(const char *name,
151 					struct device *dev,
152 					const struct rtc_class_ops *ops,
153 					struct module *owner);
154 extern struct rtc_device *devm_rtc_device_register(struct device *dev,
155 					const char *name,
156 					const struct rtc_class_ops *ops,
157 					struct module *owner);
158 extern void rtc_device_unregister(struct rtc_device *rtc);
159 extern void devm_rtc_device_unregister(struct device *dev,
160 					struct rtc_device *rtc);
161 
162 extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
163 extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
164 extern int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs);
165 extern int rtc_set_ntp_time(struct timespec64 now);
166 int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm);
167 extern int rtc_read_alarm(struct rtc_device *rtc,
168 			struct rtc_wkalrm *alrm);
169 extern int rtc_set_alarm(struct rtc_device *rtc,
170 				struct rtc_wkalrm *alrm);
171 extern int rtc_initialize_alarm(struct rtc_device *rtc,
172 				struct rtc_wkalrm *alrm);
173 extern void rtc_update_irq(struct rtc_device *rtc,
174 			unsigned long num, unsigned long events);
175 
176 extern struct rtc_device *rtc_class_open(const char *name);
177 extern void rtc_class_close(struct rtc_device *rtc);
178 
179 extern int rtc_irq_register(struct rtc_device *rtc,
180 				struct rtc_task *task);
181 extern void rtc_irq_unregister(struct rtc_device *rtc,
182 				struct rtc_task *task);
183 extern int rtc_irq_set_state(struct rtc_device *rtc,
184 				struct rtc_task *task, int enabled);
185 extern int rtc_irq_set_freq(struct rtc_device *rtc,
186 				struct rtc_task *task, int freq);
187 extern int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled);
188 extern int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled);
189 extern int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc,
190 						unsigned int enabled);
191 
192 void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode);
193 void rtc_aie_update_irq(void *private);
194 void rtc_uie_update_irq(void *private);
195 enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer);
196 
197 int rtc_register(rtc_task_t *task);
198 int rtc_unregister(rtc_task_t *task);
199 int rtc_control(rtc_task_t *t, unsigned int cmd, unsigned long arg);
200 
201 void rtc_timer_init(struct rtc_timer *timer, void (*f)(void* p), void* data);
202 int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer* timer,
203 			ktime_t expires, ktime_t period);
204 int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer* timer);
205 void rtc_timer_do_work(struct work_struct *work);
206 
207 static inline bool is_leap_year(unsigned int year)
208 {
209 	return (!(year % 4) && (year % 100)) || !(year % 400);
210 }
211 
212 #ifdef CONFIG_RTC_HCTOSYS_DEVICE
213 extern int rtc_hctosys_ret;
214 #else
215 #define rtc_hctosys_ret -ENODEV
216 #endif
217 
218 #endif /* _LINUX_RTC_H_ */
219