Committer: Michael Beasley <mike@snafu.setup>
[mikesnafu-overlay.git] / include / linux / mc146818rtc.h
blob2f4e957af6568990944e0656546fcdba9a8faf3a
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 */
11 #ifndef _MC146818RTC_H
12 #define _MC146818RTC_H
14 #include <asm/io.h>
15 #include <linux/rtc.h> /* get the user-level API */
16 #include <asm/mc146818rtc.h> /* register access macros */
18 #ifdef __KERNEL__
19 #include <linux/spinlock.h> /* spinlock_t */
20 extern spinlock_t rtc_lock; /* serialize CMOS RAM access */
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.
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.
30 struct cmos_rtc_board_info {
31 void (*wake_on)(struct device *dev);
32 void (*wake_off)(struct device *dev);
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 */
38 #endif
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
52 #define RTC_DAY_OF_WEEK 6
53 #define RTC_DAY_OF_MONTH 7
54 #define RTC_MONTH 8
55 #define RTC_YEAR 9
57 /* control registers - Moto names
59 #define RTC_REG_A 10
60 #define RTC_REG_B 11
61 #define RTC_REG_C 12
62 #define RTC_REG_D 13
64 /**********************************************************************
65 * register details
66 **********************************************************************/
67 #define RTC_FREQ_SELECT RTC_REG_A
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.
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
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 */
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
104 /**********************************************************************/
105 #define RTC_VALID RTC_REG_D
106 # define RTC_VRT 0x80 /* valid RAM and time */
107 /**********************************************************************/
109 #ifndef ARCH_RTC_LOCATION /* Override by <asm/mc146818rtc.h>? */
111 #define RTC_IO_EXTENT 0x8
112 #define RTC_IO_EXTENT_USED 0x2
113 #define RTC_IOMAPPED 1 /* Default to I/O mapping. */
115 #else
116 #define RTC_IO_EXTENT_USED RTC_IO_EXTENT
117 #endif /* ARCH_RTC_LOCATION */
119 #endif /* _MC146818RTC_H */