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
 111 #include <linux/device.h>
 112 #include <linux/seq_file.h>
 113 #include <linux/cdev.h>
 114 #include <linux/poll.h>
 115 #include <linux/mutex.h>
 116
 117 extern struct class *rtc_class;
 118
 119 /*
 120  * For these RTC methods the device parameter is the physical device
 121  * on whatever bus holds the hardware (I2C, Platform, SPI, etc), which
 122  * was passed to rtc_device_register().  Its driver_data normally holds
 123  * device state, including the rtc_device pointer for the RTC.
 124  *
 125  * Most of these methods are called with rtc_device.ops_lock held,
 126  * through the rtc_*(struct rtc_device *, ...) calls.
 127  *
 128  * The (current) exceptions are mostly filesystem hooks:
 129  *   - the proc() hook for procfs
 130  *   - non-ioctl() chardev hooks:  open(), release(), read_callback()
 131  *   - periodic irq calls:  irq_set_state(), irq_set_freq()
 132  *
 133  * REVISIT those periodic irq calls *do* have ops_lock when they're
 134  * issued through ioctl() ...
 135  */
 136 struct rtc_class_ops {
 137         int (*open)(struct device *);
 138         void (*release)(struct device *);
 139         int (*ioctl)(struct device *, unsigned int, unsigned long);
 140         int (*read_time)(struct device *, struct rtc_time *);
 141         int (*set_time)(struct device *, struct rtc_time *);
 142         int (*read_alarm)(struct device *, struct rtc_wkalrm *);
 143         int (*set_alarm)(struct device *, struct rtc_wkalrm *);
 144         int (*proc)(struct device *, struct seq_file *);
 145         int (*set_mmss)(struct device *, unsigned long secs);
 146         int (*irq_set_state)(struct device *, int enabled);
 147         int (*irq_set_freq)(struct device *, int freq);
 148         int (*read_callback)(struct device *, int data);
 149         int (*alarm_irq_enable)(struct device *, unsigned int enabled);
 150         int (*update_irq_enable)(struct device *, unsigned int enabled);
 151 };
 152
 153 #define RTC_DEVICE_NAME_SIZE 20
 154 struct rtc_task;
 155
 156 /* flags */
 157 #define RTC_DEV_BUSY 0
 158
 159 struct rtc_device
 160 {
 161         struct device dev;
 162         struct module *owner;
 163
 164         int id;
 165         char name[RTC_DEVICE_NAME_SIZE];
 166
 167         const struct rtc_class_ops *ops;
 168         struct mutex ops_lock;
 169
 170         struct cdev char_dev;
 171         unsigned long flags;
 172
 173         unsigned long irq_data;
 174         spinlock_t irq_lock;
 175         wait_queue_head_t irq_queue;
 176         struct fasync_struct *async_queue;
 177
 178         struct rtc_task *irq_task;
 179         spinlock_t irq_task_lock;
 180         int irq_freq;
 181         int max_user_freq;
 182 #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
 183         struct work_struct uie_task;
 184         struct timer_list uie_timer;
 185         /* Those fields are protected by rtc->irq_lock */
 186         unsigned int oldsecs;
 187         unsigned int uie_irq_active:1;
 188         unsigned int stop_uie_polling:1;
 189         unsigned int uie_task_active:1;
 190         unsigned int uie_timer_active:1;
 191 #endif
 192 };
 193 #define to_rtc_device(d) container_of(d, struct rtc_device, dev)
 194
 195 extern struct rtc_device *rtc_device_register(const char *name,
 196                                         struct device *dev,
 197                                         const struct rtc_class_ops *ops,
 198                                         struct module *owner);
 199 extern void rtc_device_unregister(struct rtc_device *rtc);
 200
 201 extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
 202 extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);
 203 extern int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs);
 204 extern int rtc_read_alarm(struct rtc_device *rtc,
 205                         struct rtc_wkalrm *alrm);
 206 extern int rtc_set_alarm(struct rtc_device *rtc,
 207                                 struct rtc_wkalrm *alrm);
 208 extern void rtc_update_irq(struct rtc_device *rtc,
 209                         unsigned long num, unsigned long events);
 210
 211 extern struct rtc_device *rtc_class_open(char *name);
 212 extern void rtc_class_close(struct rtc_device *rtc);
 213
 214 extern int rtc_irq_register(struct rtc_device *rtc,
 215                                 struct rtc_task *task);
 216 extern void rtc_irq_unregister(struct rtc_device *rtc,
 217                                 struct rtc_task *task);
 218 extern int rtc_irq_set_state(struct rtc_device *rtc,
 219                                 struct rtc_task *task, int enabled);
 220 extern int rtc_irq_set_freq(struct rtc_device *rtc,
 221                                 struct rtc_task *task, int freq);
 222 extern int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled);
 223 extern int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled);
 224 extern int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc,
 225                                                 unsigned int enabled);
 226
 227 typedef struct rtc_task {
 228         void (*func)(void *private_data);
 229         void *private_data;
 230 } rtc_task_t;
 231
 232 int rtc_register(rtc_task_t *task);
 233 int rtc_unregister(rtc_task_t *task);
 234 int rtc_control(rtc_task_t *t, unsigned int cmd, unsigned long arg);
 235
 236 static inline bool is_leap_year(unsigned int year)
 237 {
 238         return (!(year % 4) && (year % 100)) || !(year % 400);
 239 }
 240
 241 #ifdef CONFIG_RTC_HCTOSYS
 242 extern int rtc_hctosys_ret;
 243 #else
 244 #define rtc_hctosys_ret -ENODEV
 245 #endif
 246
 247 #endif /* __KERNEL__ */
 248
 249 #endif /* _LINUX_RTC_H_ */