char: legacy RTC cleanups

@@ -328,7 +328,7 @@ config JS_RTC
 config GEN_RTC
 	tristate "Generic /dev/rtc emulation"
 	depends on RTC!=y
-	depends on ALPHA || M68K || MN10300 || PARISC || PPC
+	depends on M68K || MN10300 || PARISC || PPC
 	---help---
 	  If you say Y here and create a character special file /dev/rtc with
 	  major number 10 and minor number 135 using mknod ("man mknod"), you

@@ -279,8 +279,7 @@ if RTC_LIB=n
 
 config RTC
 	tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
-	depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
-			&& !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN && !UML
+	depends on ALPHA || (MIPS && MACH_LOONGSON64) || MN10300 || X86
 	---help---
 	  If you say Y here and create a character special file /dev/rtc with
 	  major number 10 and minor number 135 using mknod ("man mknod"), you

@@ -1,16 +0,0 @@
-/* mc146818rtc.h: RTC defs
- *
- * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#ifndef _ASM_MC146818RTC_H
-#define _ASM_MC146818RTC_H
-
-
-#endif /* _ASM_MC146818RTC_H */

@@ -1,9 +0,0 @@
-/*
- * Machine dependent access functions for RTC registers.
- */
-#ifndef _H8300_MC146818RTC_H
-#define _H8300_MC146818RTC_H
-
-/* empty include file to satisfy the include in genrtc.c/ide-geometry.c */
-
-#endif /* _H8300_MC146818RTC_H */

@@ -1,10 +0,0 @@
-#ifndef _ASM_IA64_MC146818RTC_H
-#define _ASM_IA64_MC146818RTC_H
-
-/*
- * Machine dependent access functions for RTC registers.
- */
-
-/* empty include file to satisfy the include in genrtc.c */
-
-#endif /* _ASM_IA64_MC146818RTC_H */

@@ -1,9 +0,0 @@
-/*
- * Machine dependent access functions for RTC registers.
- */
-#ifndef _ASM_MC146818RTC_H
-#define _ASM_MC146818RTC_H
-
-/* empty include file to satisfy the include in genrtc.c */
-
-#endif /* _ASM_MC146818RTC_H */

@@ -1,7 +0,0 @@
-/*
- * Machine dependent access functions for RTC registers.
- */
-#ifndef _ASM_MC146818RTC_H
-#define _ASM_MC146818RTC_H
-
-#endif /* _ASM_MC146818RTC_H */

@@ -12,26 +12,15 @@
 
 #ifdef __KERNEL__
 
-#include <linux/rtc.h>
+#define get_rtc_time parisc_get_rtc_time
+#define set_rtc_time parisc_set_rtc_time
+#include <asm-generic/rtc.h>
 
 #include <asm/pdc.h>
 
 #define SECS_PER_HOUR   (60 * 60)
 #define SECS_PER_DAY    (SECS_PER_HOUR * 24)
 
-
-#define RTC_PIE 0x40		/* periodic interrupt enable */
-#define RTC_AIE 0x20		/* alarm interrupt enable */
-#define RTC_UIE 0x10		/* update-finished interrupt enable */
-
-#define RTC_BATT_BAD 0x100	/* battery bad */
-
-/* some dummy definitions */
-#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 __isleap(year) \
   ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
 

@@ -44,7 +33,7 @@ static const unsigned short int __mon_yday[2][13] =
 	{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
 };
 
-static inline unsigned int get_rtc_time(struct rtc_time *wtime)
+static inline unsigned int parisc_get_rtc_time(struct rtc_time *wtime)
 {
 	struct pdc_tod tod_data;
 	long int days, rem, y;

@@ -96,7 +85,7 @@ static inline unsigned int get_rtc_time(struct rtc_time *wtime)
 	return RTC_24H;
 }
 
-static int set_rtc_time(struct rtc_time *wtime)
+static int parisc_set_rtc_time(struct rtc_time *wtime)
 {
 	u_int32_t secs;
 

@@ -110,22 +99,5 @@ static int set_rtc_time(struct rtc_time *wtime)
 
 }
 
-static inline unsigned int get_rtc_ss(void)
-{
-	struct rtc_time h;
-
-	get_rtc_time(&h);
-	return h.tm_sec;
-}
-
-static inline int get_rtc_pll(struct rtc_pll_info *pll)
-{
-	return -EINVAL;
-}
-static inline int set_rtc_pll(struct rtc_pll_info *pll)
-{
-	return -EINVAL;
-}
-
 #endif /* __KERNEL__ */
 #endif /* __ASM_RTC_H__ */

@@ -328,7 +328,7 @@ config JS_RTC
 config GEN_RTC
 	tristate "Generic /dev/rtc emulation"
 	depends on RTC!=y
-	depends on M68K || MN10300 || PARISC || PPC
+	depends on M68K || PARISC || PPC
 	---help---
 	  If you say Y here and create a character special file /dev/rtc with
 	  major number 10 and minor number 135 using mknod ("man mknod"), you

@@ -26,23 +26,14 @@
 
 #ifdef __KERNEL__
 
-#include <linux/rtc.h>
+#define get_rtc_time powerpc_get_rtc_time
+#define set_rtc_time powerpc_set_rtc_time
+#include <asm-generic/rtc.h>
 
 #include <asm/machdep.h>
 #include <asm/time.h>
 
-#define RTC_PIE 0x40		/* periodic interrupt enable */
-#define RTC_AIE 0x20		/* alarm interrupt enable */
-#define RTC_UIE 0x10		/* update-finished interrupt enable */
-
-/* some dummy definitions */
-#define RTC_BATT_BAD 0x100	/* battery bad */
-#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 */
-
-static inline unsigned int get_rtc_time(struct rtc_time *time)
+static inline unsigned int powerpc_get_rtc_time(struct rtc_time *time)
 {
 	if (ppc_md.get_rtc_time)
 		ppc_md.get_rtc_time(time);

@@ -50,29 +41,12 @@ static inline unsigned int get_rtc_time(struct rtc_time *time)
 }
 
 /* Set the current date and time in the real time clock. */
-static inline int set_rtc_time(struct rtc_time *time)
+static inline int powerpc_set_rtc_time(struct rtc_time *time)
 {
 	if (ppc_md.set_rtc_time)
 		return ppc_md.set_rtc_time(time);
 	return -EINVAL;
 }
 
-static inline unsigned int get_rtc_ss(void)
-{
-	struct rtc_time h;
-
-	get_rtc_time(&h);
-	return h.tm_sec;
-}
-
-static inline int get_rtc_pll(struct rtc_pll_info *pll)
-{
-	return -EINVAL;
-}
-static inline int set_rtc_pll(struct rtc_pll_info *pll)
-{
-	return -EINVAL;
-}
-
 #endif /* __KERNEL__ */
 #endif /* __ASM_POWERPC_RTC_H__ */

@@ -279,7 +279,7 @@ if RTC_LIB=n
 
 config RTC
 	tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
-	depends on ALPHA || (MIPS && MACH_LOONGSON64) || MN10300 || X86
+	depends on ALPHA || (MIPS && MACH_LOONGSON64) || MN10300
 	---help---
 	  If you say Y here and create a character special file /dev/rtc with
 	  major number 10 and minor number 135 using mknod ("man mknod"), you

@@ -328,7 +328,7 @@ config JS_RTC
 config GEN_RTC
 	tristate "Generic /dev/rtc emulation"
 	depends on RTC!=y
-	depends on ALPHA || M68K || MN10300 || PARISC || PPC || X86
+	depends on ALPHA || M68K || MN10300 || PARISC || PPC
 	---help---
 	  If you say Y here and create a character special file /dev/rtc with
 	  major number 10 and minor number 135 using mknod ("man mknod"), you

@@ -43,7 +43,7 @@
 #include <linux/of_platform.h>
 
 /* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
-#include <asm-generic/rtc.h>
+#include <linux/mc146818rtc.h>
 
 struct cmos_rtc {
 	struct rtc_device	*rtc;

@@ -190,10 +190,10 @@ static inline void cmos_write_bank2(unsigned char val, unsigned char addr)
 static int cmos_read_time(struct device *dev, struct rtc_time *t)
 {
 	/* REVISIT:  if the clock has a "century" register, use
-	 * that instead of the heuristic in get_rtc_time().
+	 * that instead of the heuristic in mc146818_get_time().
 	 * That'll make Y3K compatility (year > 2070) easy!
 	 */
-	get_rtc_time(t);
+	mc146818_get_time(t);
 	return 0;
 }
 

@@ -205,7 +205,7 @@ static int cmos_set_time(struct device *dev, struct rtc_time *t)
 	 * takes effect exactly 500ms after we write the register.
 	 * (Also queueing and other delays before we get this far.)
 	 */
-	return set_rtc_time(t);
+	return mc146818_set_time(t);
 }
 
 static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)

@@ -1142,14 +1142,14 @@ static __init void cmos_of_init(struct platform_device *pdev)
 	if (val)
 		CMOS_WRITE(be32_to_cpup(val), RTC_FREQ_SELECT);
 
-	get_rtc_time(&time);
+	cmos_read_time(&pdev->dev, &time);
 	ret = rtc_valid_tm(&time);
 	if (ret) {
 		struct rtc_time def_time = {
 			.tm_year = 1,
 			.tm_mday = 1,
 		};
-		set_rtc_time(&def_time);
+		cmos_set_time(&pdev->dev, &def_time);
 	}
 }
 #else

@@ -12,12 +12,12 @@
 #ifndef __ASM_RTC_H__
 #define __ASM_RTC_H__
 
-#include <linux/mc146818rtc.h>
 #include <linux/rtc.h>
-#include <linux/bcd.h>
-#include <linux/delay.h>
-#ifdef CONFIG_ACPI
-#include <linux/acpi.h>
+
+#ifndef get_rtc_time
+#include <linux/mc146818rtc.h>
+#define get_rtc_time mc146818_get_time
+#define set_rtc_time mc146818_set_time
 #endif
 
 #define RTC_PIE 0x40		/* periodic interrupt enable */

@@ -31,202 +31,6 @@
 #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 */
 
-/*
- * Returns true if a clock update is in progress
- */
-static inline unsigned char rtc_is_updating(void)
-{
-	unsigned char uip;
-	unsigned long flags;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-	uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP);
-	spin_unlock_irqrestore(&rtc_lock, flags);
-	return uip;
-}
-
-static inline unsigned int __get_rtc_time(struct rtc_time *time)
-{
-	unsigned char ctrl;
-	unsigned long flags;
-	unsigned char century = 0;
-
-#ifdef CONFIG_MACH_DECSTATION
-	unsigned int real_year;
-#endif
-
-	/*
-	 * read RTC once any update in progress is done. The update
-	 * can take just over 2ms. We wait 20ms. There is no need to
-	 * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.
-	 * If you need to know *exactly* when a second has started, enable
-	 * periodic update complete interrupts, (via ioctl) and then 
-	 * immediately read /dev/rtc which will block until you get the IRQ.
-	 * Once the read clears, read the RTC time (again via ioctl). Easy.
-	 */
-	if (rtc_is_updating())
-		mdelay(20);
-
-	/*
-	 * Only the values that we read from the RTC are set. We leave
-	 * tm_wday, tm_yday and tm_isdst untouched. Even though the
-	 * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
-	 * by the RTC when initially set to a non-zero value.
-	 */
-	spin_lock_irqsave(&rtc_lock, flags);
-	time->tm_sec = CMOS_READ(RTC_SECONDS);
-	time->tm_min = CMOS_READ(RTC_MINUTES);
-	time->tm_hour = CMOS_READ(RTC_HOURS);
-	time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
-	time->tm_mon = CMOS_READ(RTC_MONTH);
-	time->tm_year = CMOS_READ(RTC_YEAR);
-#ifdef CONFIG_MACH_DECSTATION
-	real_year = CMOS_READ(RTC_DEC_YEAR);
-#endif
-#ifdef CONFIG_ACPI
-	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
-	    acpi_gbl_FADT.century)
-		century = CMOS_READ(acpi_gbl_FADT.century);
-#endif
-	ctrl = CMOS_READ(RTC_CONTROL);
-	spin_unlock_irqrestore(&rtc_lock, flags);
-
-	if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
-	{
-		time->tm_sec = bcd2bin(time->tm_sec);
-		time->tm_min = bcd2bin(time->tm_min);
-		time->tm_hour = bcd2bin(time->tm_hour);
-		time->tm_mday = bcd2bin(time->tm_mday);
-		time->tm_mon = bcd2bin(time->tm_mon);
-		time->tm_year = bcd2bin(time->tm_year);
-		century = bcd2bin(century);
-	}
-
-#ifdef CONFIG_MACH_DECSTATION
-	time->tm_year += real_year - 72;
-#endif
-
-	if (century)
-		time->tm_year += (century - 19) * 100;
-
-	/*
-	 * Account for differences between how the RTC uses the values
-	 * and how they are defined in a struct rtc_time;
-	 */
-	if (time->tm_year <= 69)
-		time->tm_year += 100;
-
-	time->tm_mon--;
-
-	return RTC_24H;
-}
-
-#ifndef get_rtc_time
-#define get_rtc_time	__get_rtc_time
-#endif
-
-/* Set the current date and time in the real time clock. */
-static inline int __set_rtc_time(struct rtc_time *time)
-{
-	unsigned long flags;
-	unsigned char mon, day, hrs, min, sec;
-	unsigned char save_control, save_freq_select;
-	unsigned int yrs;
-#ifdef CONFIG_MACH_DECSTATION
-	unsigned int real_yrs, leap_yr;
-#endif
-	unsigned char century = 0;
-
-	yrs = time->tm_year;
-	mon = time->tm_mon + 1;   /* tm_mon starts at zero */
-	day = time->tm_mday;
-	hrs = time->tm_hour;
-	min = time->tm_min;
-	sec = time->tm_sec;
-
-	if (yrs > 255)	/* They are unsigned */
-		return -EINVAL;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-#ifdef CONFIG_MACH_DECSTATION
-	real_yrs = yrs;
-	leap_yr = ((!((yrs + 1900) % 4) && ((yrs + 1900) % 100)) ||
-			!((yrs + 1900) % 400));
-	yrs = 72;
-
-	/*
-	 * We want to keep the year set to 73 until March
-	 * for non-leap years, so that Feb, 29th is handled
-	 * correctly.
-	 */
-	if (!leap_yr && mon < 3) {
-		real_yrs--;
-		yrs = 73;
-	}
-#endif
-
-#ifdef CONFIG_ACPI
-	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
-	    acpi_gbl_FADT.century) {
-		century = (yrs + 1900) / 100;
-		yrs %= 100;
-	}
-#endif
-
-	/* These limits and adjustments are independent of
-	 * whether the chip is in binary mode or not.
-	 */
-	if (yrs > 169) {
-		spin_unlock_irqrestore(&rtc_lock, flags);
-		return -EINVAL;
-	}
-
-	if (yrs >= 100)
-		yrs -= 100;
-
-	if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY)
-	    || RTC_ALWAYS_BCD) {
-		sec = bin2bcd(sec);
-		min = bin2bcd(min);
-		hrs = bin2bcd(hrs);
-		day = bin2bcd(day);
-		mon = bin2bcd(mon);
-		yrs = bin2bcd(yrs);
-		century = bin2bcd(century);
-	}
-
-	save_control = CMOS_READ(RTC_CONTROL);
-	CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
-	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
-	CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
-
-#ifdef CONFIG_MACH_DECSTATION
-	CMOS_WRITE(real_yrs, RTC_DEC_YEAR);
-#endif
-	CMOS_WRITE(yrs, RTC_YEAR);
-	CMOS_WRITE(mon, RTC_MONTH);
-	CMOS_WRITE(day, RTC_DAY_OF_MONTH);
-	CMOS_WRITE(hrs, RTC_HOURS);
-	CMOS_WRITE(min, RTC_MINUTES);
-	CMOS_WRITE(sec, RTC_SECONDS);
-#ifdef CONFIG_ACPI
-	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
-	    acpi_gbl_FADT.century)
-		CMOS_WRITE(century, acpi_gbl_FADT.century);
-#endif
-
-	CMOS_WRITE(save_control, RTC_CONTROL);
-	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
-
-	spin_unlock_irqrestore(&rtc_lock, flags);
-
-	return 0;
-}
-
-#ifndef set_rtc_time
-#define set_rtc_time	__set_rtc_time
-#endif
-
 static inline unsigned int get_rtc_ss(void)
 {
 	struct rtc_time h;

@@ -14,6 +14,12 @@
 #include <asm/io.h>
 #include <linux/rtc.h>			/* get the user-level API */
 #include <asm/mc146818rtc.h>		/* register access macros */
+#include <linux/bcd.h>
+#include <linux/delay.h>
+
+#ifdef CONFIG_ACPI
+#include <linux/acpi.h>
+#endif
 
 #ifdef __KERNEL__
 #include <linux/spinlock.h>		/* spinlock_t */

@@ -120,4 +126,192 @@ struct cmos_rtc_board_info {
 #define RTC_IO_EXTENT_USED      RTC_IO_EXTENT
 #endif /* ARCH_RTC_LOCATION */
 
+/*
+ * Returns true if a clock update is in progress
+ */
+static inline unsigned char mc146818_is_updating(void)
+{
+	unsigned char uip;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return uip;
+}
+
+static inline unsigned int mc146818_get_time(struct rtc_time *time)
+{
+	unsigned char ctrl;
+	unsigned long flags;
+	unsigned char century = 0;
+
+#ifdef CONFIG_MACH_DECSTATION
+	unsigned int real_year;
+#endif
+
+	/*
+	 * read RTC once any update in progress is done. The update
+	 * can take just over 2ms. We wait 20ms. There is no need to
+	 * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.
+	 * If you need to know *exactly* when a second has started, enable
+	 * periodic update complete interrupts, (via ioctl) and then 
+	 * immediately read /dev/rtc which will block until you get the IRQ.
+	 * Once the read clears, read the RTC time (again via ioctl). Easy.
+	 */
+	if (mc146818_is_updating())
+		mdelay(20);
+
+	/*
+	 * Only the values that we read from the RTC are set. We leave
+	 * tm_wday, tm_yday and tm_isdst untouched. Even though the
+	 * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
+	 * by the RTC when initially set to a non-zero value.
+	 */
+	spin_lock_irqsave(&rtc_lock, flags);
+	time->tm_sec = CMOS_READ(RTC_SECONDS);
+	time->tm_min = CMOS_READ(RTC_MINUTES);
+	time->tm_hour = CMOS_READ(RTC_HOURS);
+	time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
+	time->tm_mon = CMOS_READ(RTC_MONTH);
+	time->tm_year = CMOS_READ(RTC_YEAR);
+#ifdef CONFIG_MACH_DECSTATION
+	real_year = CMOS_READ(RTC_DEC_YEAR);
+#endif
+#ifdef CONFIG_ACPI
+	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
+	    acpi_gbl_FADT.century)
+		century = CMOS_READ(acpi_gbl_FADT.century);
+#endif
+	ctrl = CMOS_READ(RTC_CONTROL);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+
+	if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
+	{
+		time->tm_sec = bcd2bin(time->tm_sec);
+		time->tm_min = bcd2bin(time->tm_min);
+		time->tm_hour = bcd2bin(time->tm_hour);
+		time->tm_mday = bcd2bin(time->tm_mday);
+		time->tm_mon = bcd2bin(time->tm_mon);
+		time->tm_year = bcd2bin(time->tm_year);
+		century = bcd2bin(century);
+	}
+
+#ifdef CONFIG_MACH_DECSTATION
+	time->tm_year += real_year - 72;
+#endif
+
+	if (century)
+		time->tm_year += (century - 19) * 100;
+
+	/*
+	 * Account for differences between how the RTC uses the values
+	 * and how they are defined in a struct rtc_time;
+	 */
+	if (time->tm_year <= 69)
+		time->tm_year += 100;
+
+	time->tm_mon--;
+
+	return RTC_24H;
+}
+
+/* Set the current date and time in the real time clock. */
+static inline int mc146818_set_time(struct rtc_time *time)
+{
+	unsigned long flags;
+	unsigned char mon, day, hrs, min, sec;
+	unsigned char save_control, save_freq_select;
+	unsigned int yrs;
+#ifdef CONFIG_MACH_DECSTATION
+	unsigned int real_yrs, leap_yr;
+#endif
+	unsigned char century = 0;
+
+	yrs = time->tm_year;
+	mon = time->tm_mon + 1;   /* tm_mon starts at zero */
+	day = time->tm_mday;
+	hrs = time->tm_hour;
+	min = time->tm_min;
+	sec = time->tm_sec;
+
+	if (yrs > 255)	/* They are unsigned */
+		return -EINVAL;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+#ifdef CONFIG_MACH_DECSTATION
+	real_yrs = yrs;
+	leap_yr = ((!((yrs + 1900) % 4) && ((yrs + 1900) % 100)) ||
+			!((yrs + 1900) % 400));
+	yrs = 72;
+
+	/*
+	 * We want to keep the year set to 73 until March
+	 * for non-leap years, so that Feb, 29th is handled
+	 * correctly.
+	 */
+	if (!leap_yr && mon < 3) {
+		real_yrs--;
+		yrs = 73;
+	}
+#endif
+
+#ifdef CONFIG_ACPI
+	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
+	    acpi_gbl_FADT.century) {
+		century = (yrs + 1900) / 100;
+		yrs %= 100;
+	}
+#endif
+
+	/* These limits and adjustments are independent of
+	 * whether the chip is in binary mode or not.
+	 */
+	if (yrs > 169) {
+		spin_unlock_irqrestore(&rtc_lock, flags);
+		return -EINVAL;
+	}
+
+	if (yrs >= 100)
+		yrs -= 100;
+
+	if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY)
+	    || RTC_ALWAYS_BCD) {
+		sec = bin2bcd(sec);
+		min = bin2bcd(min);
+		hrs = bin2bcd(hrs);
+		day = bin2bcd(day);
+		mon = bin2bcd(mon);
+		yrs = bin2bcd(yrs);
+		century = bin2bcd(century);
+	}
+
+	save_control = CMOS_READ(RTC_CONTROL);
+	CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
+	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
+	CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
+
+#ifdef CONFIG_MACH_DECSTATION
+	CMOS_WRITE(real_yrs, RTC_DEC_YEAR);
+#endif
+	CMOS_WRITE(yrs, RTC_YEAR);
+	CMOS_WRITE(mon, RTC_MONTH);
+	CMOS_WRITE(day, RTC_DAY_OF_MONTH);
+	CMOS_WRITE(hrs, RTC_HOURS);
+	CMOS_WRITE(min, RTC_MINUTES);
+	CMOS_WRITE(sec, RTC_SECONDS);
+#ifdef CONFIG_ACPI
+	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
+	    acpi_gbl_FADT.century)
+		CMOS_WRITE(century, acpi_gbl_FADT.century);
+#endif
+
+	CMOS_WRITE(save_control, RTC_CONTROL);
+	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
+
+	spin_unlock_irqrestore(&rtc_lock, flags);
+
+	return 0;
+}
+
 #endif /* _MC146818RTC_H */