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Diffstat (limited to 'include/linux/mc146818rtc.h')
| -rw-r--r-- | include/linux/mc146818rtc.h | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/include/linux/mc146818rtc.h b/include/linux/mc146818rtc.h new file mode 100644 index 000000000..741aa2dc5 --- /dev/null +++ b/include/linux/mc146818rtc.h @@ -0,0 +1,104 @@ +/* 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> + +#define CMOS_READ(addr) ({ \ +outb_p(addr|0x80,0x70); \ +inb_p(0x71); \ +}) +#define CMOS_WRITE(val, addr) ({ \ +outb_p(addr|0x80,0x70); \ +outb_p(val,0x71); \ +}) + +/********************************************************************** + * 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 */ +/**********************************************************************/ + +/* example: !(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) + * determines if the following two #defines are needed + */ +#ifndef BCD_TO_BIN +#define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10) +#endif + +#ifndef BIN_TO_BCD +#define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10) +#endif + +#endif /* _MC146818RTC_H */ |