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/* 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 <linux/spinlock.h> /* spinlock_t */
#include <asm/mc146818rtc.h> /* register access macros */
extern spinlock_t rtc_lock; /* serialize CMOS RAM access */
/**********************************************************************
* 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 */
/**********************************************************************/
#endif /* _MC146818RTC_H */