include/linux/rtc.h

   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  * The struct used to pass data via the following ioctl. Similar to the
  16  * struct tm in <time.h>, but it needs to be here so that the kernel
  17  * source is self contained, allowing cross-compiles, etc. etc.
  18  */
  19
  20 struct rtc_time {
  21         int tm_sec;
  22         int tm_min;
  23         int tm_hour;
  24         int tm_mday;
  25         int tm_mon;
  26         int tm_year;
  27         int tm_wday;
  28         int tm_yday;
  29         int tm_isdst;
  30 };
  31
  32 /*
  33  * This data structure is inspired by the EFI (v0.92) wakeup
  34  * alarm API.
  35  */
  36 struct rtc_wkalrm {
  37         unsigned char enabled;  /* 0 = alarm disabled, 1 = alarm enabled */
  38         unsigned char pending;  /* 0 = alarm not pending, 1 = alarm pending */
  39         struct rtc_time time;   /* time the alarm is set to */
  40 };
  41
  42 /*
  43  * Data structure to control PLL correction some better RTC feature
  44  * pll_value is used to get or set current value of correction,
  45  * the rest of the struct is used to query HW capabilities.
  46  * This is modeled after the RTC used in Q40/Q60 computers but
  47  * should be sufficiently flexible for other devices
  48  *
  49  * +ve pll_value means clock will run faster by
  50  *   pll_value*pll_posmult/pll_clock
  51  * -ve pll_value means clock will run slower by
  52  *   pll_value*pll_negmult/pll_clock
  53  */
  54
  55 struct rtc_pll_info {
  56         int pll_ctrl;       /* placeholder for fancier control */
  57         int pll_value;      /* get/set correction value */
  58         int pll_max;        /* max +ve (faster) adjustment value */
  59         int pll_min;        /* max -ve (slower) adjustment value */
  60         int pll_posmult;    /* factor for +ve correction */
  61         int pll_negmult;    /* factor for -ve correction */
  62         long pll_clock;     /* base PLL frequency */
  63 };
  64
  65 /*
  66  * ioctl calls that are permitted to the /dev/rtc interface, if
  67  * any of the RTC drivers are enabled.
  68  */
  69
  70 #define RTC_AIE_ON      _IO('p', 0x01)  /* Alarm int. enable on         */
  71 #define RTC_AIE_OFF     _IO('p', 0x02)  /* ... off                      */
  72 #define RTC_UIE_ON      _IO('p', 0x03)  /* Update int. enable on        */
  73 #define RTC_UIE_OFF     _IO('p', 0x04)  /* ... off                      */
  74 #define RTC_PIE_ON      _IO('p', 0x05)  /* Periodic int. enable on      */
  75 #define RTC_PIE_OFF     _IO('p', 0x06)  /* ... off                      */
  76 #define RTC_WIE_ON      _IO('p', 0x0f)  /* Watchdog int. enable on      */
  77 #define RTC_WIE_OFF     _IO('p', 0x10)  /* ... off                      */
  78
  79 #define RTC_ALM_SET     _IOW('p', 0x07, struct rtc_time) /* Set alarm time  */
  80 #define RTC_ALM_READ    _IOR('p', 0x08, struct rtc_time) /* Read alarm time */
  81 #define RTC_RD_TIME     _IOR('p', 0x09, struct rtc_time) /* Read RTC time   */
  82 #define RTC_SET_TIME    _IOW('p', 0x0a, struct rtc_time) /* Set RTC time    */
  83 #define RTC_IRQP_READ   _IOR('p', 0x0b, unsigned long)   /* Read IRQ rate   */
  84 #define RTC_IRQP_SET    _IOW('p', 0x0c, unsigned long)   /* Set IRQ rate    */
  85 #define RTC_EPOCH_READ  _IOR('p', 0x0d, unsigned long)   /* Read epoch      */
  86 #define RTC_EPOCH_SET   _IOW('p', 0x0e, unsigned long)   /* Set epoch       */
  87
  88 #define RTC_WKALM_SET   _IOW('p', 0x0f, struct rtc_wkalrm)/* Set wakeup alarm*/
  89 #define RTC_WKALM_RD    _IOR('p', 0x10, struct rtc_wkalrm)/* Get wakeup alarm*/
  90
  91 #define RTC_PLL_GET     _IOR('p', 0x11, struct rtc_pll_info)  /* Get PLL correction */
  92 #define RTC_PLL_SET     _IOW('p', 0x12, struct rtc_pll_info)  /* Set PLL correction */
  93
  94 /* interrupt flags */
  95 #define RTC_IRQF 0x80 /* any of the following is active */
  96 #define RTC_PF 0x40
  97 #define RTC_AF 0x20
  98 #define RTC_UF 0x10
  99
 100 #ifdef __KERNEL__
 101
 102 #include <linux/types.h>
 103 #include <linux/interrupt.h>
 104
 105 extern int rtc_month_days(unsigned int month, unsigned int year);
 106 extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year);
 107 extern int rtc_valid_tm(struct rtc_time *tm);
 108 extern int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time);
 109 extern void rtc_time_to_tm(unsigned long time, struct rtc_time *tm);
 110 ktime_t rtc_tm_to_ktime(struct rtc_time tm);
 111 struct rtc_time rtc_ktime_to_tm(ktime_t kt);
 112
 113
 114 #include <linux/device.h>
 115 #include <linux/seq_file.h>
 116 #include <linux/cdev.h>
 117 #include <linux/poll.h>
 118 #include <linux/mutex.h>
 119 #include <linux/timerqueue.h>
 120 #include <linux/workqueue.h>
 121
 122 extern struct class *rtc_class;
 123
 124 /*
 125  * For these RTC methods the device parameter is the physical device
 126  * on whatever bus holds the hardware (I2C, Platform, SPI, etc), which
 127  * was passed to rtc_device_register().  Its driver_data normally holds
 128  * device state, including the rtc_device pointer for the RTC.
 129  *
 130  * Most of these methods are called with rtc_device.ops_lock held,
 131  * through the rtc_*(struct rtc_device *, ...) calls.
 132  *
 133  * The (current) exceptions are mostly filesystem hooks:
 134  *   - the proc() hook for procfs
 135  *   - non-ioctl() chardev hooks:  open(), release(), read_callback()
 136  *   - periodic irq calls:  irq_set_state(), irq_set_freq()
 137  *
 138  * REVISIT those periodic irq calls *do* have ops_lock when they're
 139  * issued through ioctl() ...
 140  */
 141 struct rtc_class_ops {
 142         int (*open)(struct device *);
 143         void (*release)(struct device *);
 144         int (*ioctl)(struct device *, unsigned int, unsigned long);
 145         int (*read_time)(struct device *, struct rtc_time *);
 146         int (*set_time)(struct device *, struct rtc_time *);
 147         int (*read_alarm)(struct device *, struct rtc_wkalrm *);
 148         int (*set_alarm)(struct device *, struct rtc_wkalrm *);
 149         int (*proc)(struct device *, struct seq_file *);
 150         int (*set_mmss)(struct device *, unsigned long secs);
 151         int (*irq_set_state)(struct device *, int enabled);
 152         int (*irq_set_freq)(struct device *, int freq);
 153         int (*read_callback)(struct device *, int data);
 154         int (*alarm_irq_enable)(struct device *, unsigned int enabled);
 155         int (*update_irq_enable)(struct device *, unsigned int enabled);
 156 };
 157
 158 #define RTC_DEVICE_NAME_SIZE 20
 159 typedef struct rtc_task {
 160         void (*func)(void *private_data);
 161         void *private_data;
 162 } rtc_task_t;
 163
 164
 165 struct rtc_timer {
 166         struct rtc_task task;
 167         struct timerqueue_node node;
 168         ktime_t period;
 169         int enabled;
 170 };
 171
 172
 173 /* flags */
 174 #define RTC_DEV_BUSY 0
 175
 176 struct rtc_device
 177 {
 178         struct device dev;
 179         struct module *owner;
 180
 181         int id;
 182         char name[RTC_DEVICE_NAME_SIZE];
 183
 184         const struct rtc_class_ops *ops;
 185         struct mutex ops_lock;
 186
 187         struct cdev char_dev;
 188         unsigned long flags;
 189
 190         unsigned long irq_data;
 191         spinlock_t irq_lock;
 192         wait_queue_head_t irq_queue;
 193         struct fasync_struct *async_queue;
 194
 195         struct rtc_task *irq_task;
 196         spinlock_t irq_task_lock;
 197         int irq_freq;
 198         int max_user_freq;
 199
 200         struct timerqueue_head timerqueue;
 201         struct rtc_timer aie_timer;
 202         struct rtc_timer uie_rtctimer;
 203         struct hrtimer pie_timer; /* sub second exp, so needs hrtimer */
 204         int pie_enabled;
 205         struct work_struct irqwork;
 206 };
 207 #define to_rtc_device(d) container_of(d, struct rtc_device, dev)
 208
 209 extern struct rtc_device *rtc_device_register(const char *name,
 210                                         struct device *dev,
 211                                         const struct rtc_class_ops *ops,
 212                                         struct module *owner);
 213 extern void rtc_device_unregister(struct rtc_device *rtc);
 214
 215 extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
 216 extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
 217 extern int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs);
 218 extern int rtc_read_alarm(struct rtc_device *rtc,
 219                         struct rtc_wkalrm *alrm);
 220 extern int rtc_set_alarm(struct rtc_device *rtc,
 221                                 struct rtc_wkalrm *alrm);
 222 extern void rtc_update_irq(struct rtc_device *rtc,
 223                         unsigned long num, unsigned long events);
 224
 225 extern struct rtc_device *rtc_class_open(char *name);
 226 extern void rtc_class_close(struct rtc_device *rtc);
 227
 228 extern int rtc_irq_register(struct rtc_device *rtc,
 229                                 struct rtc_task *task);
 230 extern void rtc_irq_unregister(struct rtc_device *rtc,
 231                                 struct rtc_task *task);
 232 extern int rtc_irq_set_state(struct rtc_device *rtc,
 233                                 struct rtc_task *task, int enabled);
 234 extern int rtc_irq_set_freq(struct rtc_device *rtc,
 235                                 struct rtc_task *task, int freq);
 236 extern int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled);
 237 extern int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled);
 238 extern int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc,
 239                                                 unsigned int enabled);
 240
 241 void rtc_aie_update_irq(void *private);
 242 void rtc_uie_update_irq(void *private);
 243 enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer);
 244
 245 int rtc_register(rtc_task_t *task);
 246 int rtc_unregister(rtc_task_t *task);
 247 int rtc_control(rtc_task_t *t, unsigned int cmd, unsigned long arg);
 248
 249 void rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer);
 250 void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer);
 251 void rtc_timer_init(struct rtc_timer *timer, void (*f)(void* p), void* data);
 252 int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer* timer,
 253                         ktime_t expires, ktime_t period);
 254 int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer* timer);
 255 void rtc_timer_do_work(struct work_struct *work);
 256
 257 static inline bool is_leap_year(unsigned int year)
 258 {
 259         return (!(year % 4) && (year % 100)) || !(year % 400);
 260 }
 261
 262 #ifdef CONFIG_RTC_HCTOSYS
 263 extern int rtc_hctosys_ret;
 264 #else
 265 #define rtc_hctosys_ret -ENODEV
 266 #endif
 267
 268 #endif /* __KERNEL__ */
 269
 270 #endif /* _LINUX_RTC_H_ */