summaryrefslogtreecommitdiffstats
path: root/include/linux/mc146818rtc.h
blob: 808bb4cee2300ecf21611f492cb1fcbf1e519717 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/* mc146818rtc.h - register definitions for the Real-Time-Clock / CMOS RAM
 * Copyright Torsten Duwe <duwe@informatik.uni-erlangen.de> 1993
 * derived from Data Sheet, Copyright Motorola 1984 (!).
 * It was written to be part of the Linux operating system.
 */
/* permission is hereby granted to copy, modify and redistribute this code
 * in terms of the GNU Library General Public License, Version 2 or later,
 * at your option.
 */

#ifndef _MC146818RTC_H
#define _MC146818RTC_H

#include <asm/io.h>
#include <linux/rtc.h>			/* get the user-level API */
#include <asm/mc146818rtc.h>		/* register access macros */
#include <linux/bcd.h>
#include <linux/delay.h>
#include <linux/pm-trace.h>

#ifdef __KERNEL__
#include <linux/spinlock.h>		/* spinlock_t */
extern spinlock_t rtc_lock;		/* serialize CMOS RAM access */

/* Some RTCs extend the mc146818 register set to support alarms of more
 * than 24 hours in the future; or dates that include a century code.
 * This platform_data structure can pass this information to the driver.
 *
 * Also, some platforms need suspend()/resume() hooks to kick in special
 * handling of wake alarms, e.g. activating ACPI BIOS hooks or setting up
 * a separate wakeup alarm used by some almost-clone chips.
 */
struct cmos_rtc_board_info {
	void	(*wake_on)(struct device *dev);
	void	(*wake_off)(struct device *dev);

	u32	flags;
#define CMOS_RTC_FLAGS_NOFREQ	(1 << 0)
	int	address_space;

	u8	rtc_day_alarm;		/* zero, or register index */
	u8	rtc_mon_alarm;		/* zero, or register index */
	u8	rtc_century;		/* zero, or register index */
};
#endif

/**********************************************************************
 * register summary
 **********************************************************************/
#define RTC_SECONDS		0
#define RTC_SECONDS_ALARM	1
#define RTC_MINUTES		2
#define RTC_MINUTES_ALARM	3
#define RTC_HOURS		4
#define RTC_HOURS_ALARM		5
/* RTC_*_alarm is always true if 2 MSBs are set */
# define RTC_ALARM_DONT_CARE 	0xC0

#define RTC_DAY_OF_WEEK		6
#define RTC_DAY_OF_MONTH	7
#define RTC_MONTH		8
#define RTC_YEAR		9

/* control registers - Moto names
 */
#define RTC_REG_A		10
#define RTC_REG_B		11
#define RTC_REG_C		12
#define RTC_REG_D		13

/**********************************************************************
 * register details
 **********************************************************************/
#define RTC_FREQ_SELECT	RTC_REG_A

/* update-in-progress  - set to "1" 244 microsecs before RTC goes off the bus,
 * reset after update (may take 1.984ms @ 32768Hz RefClock) is complete,
 * totalling to a max high interval of 2.228 ms.
 */
# define RTC_UIP		0x80
# define RTC_DIV_CTL		0x70
   /* divider control: refclock values 4.194 / 1.049 MHz / 32.768 kHz */
#  define RTC_REF_CLCK_4MHZ	0x00
#  define RTC_REF_CLCK_1MHZ	0x10
#  define RTC_REF_CLCK_32KHZ	0x20
   /* 2 values for divider stage reset, others for "testing purposes only" */
#  define RTC_DIV_RESET1	0x60
#  define RTC_DIV_RESET2	0x70
  /* Periodic intr. / Square wave rate select. 0=none, 1=32.8kHz,... 15=2Hz */
# define RTC_RATE_SELECT 	0x0F

/**********************************************************************/
#define RTC_CONTROL	RTC_REG_B
# define RTC_SET 0x80		/* disable updates for clock setting */
# define RTC_PIE 0x40		/* periodic interrupt enable */
# define RTC_AIE 0x20		/* alarm interrupt enable */
# define RTC_UIE 0x10		/* update-finished interrupt enable */
# define RTC_SQWE 0x08		/* enable square-wave output */
# define RTC_DM_BINARY 0x04	/* all time/date values are BCD if clear */
# define RTC_24H 0x02		/* 24 hour mode - else hours bit 7 means pm */
# define RTC_DST_EN 0x01	/* auto switch DST - works f. USA only */

/**********************************************************************/
#define RTC_INTR_FLAGS	RTC_REG_C
/* caution - cleared by read */
# define RTC_IRQF 0x80		/* any of the following 3 is active */
# define RTC_PF 0x40
# define RTC_AF 0x20
# define RTC_UF 0x10

/**********************************************************************/
#define RTC_VALID	RTC_REG_D
# define RTC_VRT 0x80		/* valid RAM and time */
/**********************************************************************/

#ifndef ARCH_RTC_LOCATION	/* Override by <asm/mc146818rtc.h>? */

#define RTC_IO_EXTENT	0x8
#define RTC_IO_EXTENT_USED	0x2
#define RTC_IOMAPPED	1	/* Default to I/O mapping. */

#else
#define RTC_IO_EXTENT_USED      RTC_IO_EXTENT
#endif /* ARCH_RTC_LOCATION */

bool mc146818_does_rtc_work(void);
int mc146818_get_time(struct rtc_time *time);
int mc146818_set_time(struct rtc_time *time);

bool mc146818_avoid_UIP(void (*callback)(unsigned char seconds, void *param),
			void *param);

#endif /* _MC146818RTC_H */