mc146818rtc.h

  1/* mc146818rtc.h - register definitions for the Real-Time-Clock / CMOS RAM
  2 * Copyright Torsten Duwe <duwe@informatik.uni-erlangen.de> 1993
  3 * derived from Data Sheet, Copyright Motorola 1984 (!).
  4 * It was written to be part of the Linux operating system.
  5 */
  6/* permission is hereby granted to copy, modify and redistribute this code
  7 * in terms of the GNU Library General Public License, Version 2 or later,
  8 * at your option.
  9 */
 10
 11#ifndef _MC146818RTC_H
 12#define _MC146818RTC_H
 13
 14#include <asm/io.h>
 15#include <linux/rtc.h>			/* get the user-level API */
 16#include <asm/mc146818rtc.h>		/* register access macros */
 17#include <linux/bcd.h>
 18#include <linux/delay.h>
 19#include <linux/pm-trace.h>
 20
 21#ifdef __KERNEL__
 22#include <linux/spinlock.h>		/* spinlock_t */
 23extern spinlock_t rtc_lock;		/* serialize CMOS RAM access */
 24
 25/* Some RTCs extend the mc146818 register set to support alarms of more
 26 * than 24 hours in the future; or dates that include a century code.
 27 * This platform_data structure can pass this information to the driver.
 28 *
 29 * Also, some platforms need suspend()/resume() hooks to kick in special
 30 * handling of wake alarms, e.g. activating ACPI BIOS hooks or setting up
 31 * a separate wakeup alarm used by some almost-clone chips.
 32 */
 33struct cmos_rtc_board_info {
 34	void	(*wake_on)(struct device *dev);
 35	void	(*wake_off)(struct device *dev);
 36
 37	u32	flags;
 38#define CMOS_RTC_FLAGS_NOFREQ	(1 << 0)
 39	int	address_space;
 40
 41	u8	rtc_day_alarm;		/* zero, or register index */
 42	u8	rtc_mon_alarm;		/* zero, or register index */
 43	u8	rtc_century;		/* zero, or register index */
 44};
 45#endif
 46
 47/**********************************************************************
 48 * register summary
 49 **********************************************************************/
 50#define RTC_SECONDS		0
 51#define RTC_SECONDS_ALARM	1
 52#define RTC_MINUTES		2
 53#define RTC_MINUTES_ALARM	3
 54#define RTC_HOURS		4
 55#define RTC_HOURS_ALARM		5
 56/* RTC_*_alarm is always true if 2 MSBs are set */
 57# define RTC_ALARM_DONT_CARE 	0xC0
 58
 59#define RTC_DAY_OF_WEEK		6
 60#define RTC_DAY_OF_MONTH	7
 61#define RTC_MONTH		8
 62#define RTC_YEAR		9
 63
 64/* control registers - Moto names
 65 */
 66#define RTC_REG_A		10
 67#define RTC_REG_B		11
 68#define RTC_REG_C		12
 69#define RTC_REG_D		13
 70
 71/**********************************************************************
 72 * register details
 73 **********************************************************************/
 74#define RTC_FREQ_SELECT	RTC_REG_A
 75
 76/* update-in-progress  - set to "1" 244 microsecs before RTC goes off the bus,
 77 * reset after update (may take 1.984ms @ 32768Hz RefClock) is complete,
 78 * totalling to a max high interval of 2.228 ms.
 79 */
 80# define RTC_UIP		0x80
 81# define RTC_DIV_CTL		0x70
 82   /* divider control: refclock values 4.194 / 1.049 MHz / 32.768 kHz */
 83#  define RTC_REF_CLCK_4MHZ	0x00
 84#  define RTC_REF_CLCK_1MHZ	0x10
 85#  define RTC_REF_CLCK_32KHZ	0x20
 86   /* 2 values for divider stage reset, others for "testing purposes only" */
 87#  define RTC_DIV_RESET1	0x60
 88#  define RTC_DIV_RESET2	0x70
 89   /* In AMD BKDG bit 5 and 6 are reserved, bit 4 is for select dv0 bank */
 90#  define RTC_AMD_BANK_SELECT	0x10
 91  /* Periodic intr. / Square wave rate select. 0=none, 1=32.8kHz,... 15=2Hz */
 92# define RTC_RATE_SELECT 	0x0F
 93
 94/**********************************************************************/
 95#define RTC_CONTROL	RTC_REG_B
 96# define RTC_SET 0x80		/* disable updates for clock setting */
 97# define RTC_PIE 0x40		/* periodic interrupt enable */
 98# define RTC_AIE 0x20		/* alarm interrupt enable */
 99# define RTC_UIE 0x10		/* update-finished interrupt enable */
100# define RTC_SQWE 0x08		/* enable square-wave output */
101# define RTC_DM_BINARY 0x04	/* all time/date values are BCD if clear */
102# define RTC_24H 0x02		/* 24 hour mode - else hours bit 7 means pm */
103# define RTC_DST_EN 0x01	/* auto switch DST - works f. USA only */
104
105/**********************************************************************/
106#define RTC_INTR_FLAGS	RTC_REG_C
107/* caution - cleared by read */
108# define RTC_IRQF 0x80		/* any of the following 3 is active */
109# define RTC_PF 0x40
110# define RTC_AF 0x20
111# define RTC_UF 0x10
112
113/**********************************************************************/
114#define RTC_VALID	RTC_REG_D
115# define RTC_VRT 0x80		/* valid RAM and time */
116/**********************************************************************/
117
118#ifndef ARCH_RTC_LOCATION	/* Override by <asm/mc146818rtc.h>? */
119
120#define RTC_IO_EXTENT	0x8
121#define RTC_IO_EXTENT_USED	0x2
122#define RTC_IOMAPPED	1	/* Default to I/O mapping. */
123
124#else
125#define RTC_IO_EXTENT_USED      RTC_IO_EXTENT
126#endif /* ARCH_RTC_LOCATION */
127
128bool mc146818_does_rtc_work(void);
129int mc146818_get_time(struct rtc_time *time, int timeout);
130int mc146818_set_time(struct rtc_time *time);
131
132bool mc146818_avoid_UIP(void (*callback)(unsigned char seconds, void *param),
133			int timeout,
134			void *param);
135
136#endif /* _MC146818RTC_H */