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-rw-r--r--include/linux/mc146818rtc.h98
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diff --git a/include/linux/mc146818rtc.h b/include/linux/mc146818rtc.h
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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 <asm/mc146818rtc.h> /* register access macros */
+
+/**********************************************************************
+ * 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 */