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