patch-2.4.19 linux-2.4.19/arch/mips/jmr3927/common/rtc_ds1742.c

• Lines: 174
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/mips/jmr3927/common/rtc_ds1742.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/mips/jmr3927/common/rtc_ds1742.c linux-2.4.19/arch/mips/jmr3927/common/rtc_ds1742.c
@@ -0,0 +1,173 @@
+/***********************************************************************
+ *
+ * Copyright 2001 MontaVista Software Inc.
+ * Author: MontaVista Software, Inc.
+ *              ahennessy@mvista.com       
+ *
+ * arch/mips/jmr3927/common/rtc_ds1742.c
+ * Based on arch/mips/ddb5xxx/common/rtc_ds1386.c
+ *     low-level RTC hookups for s for Dallas 1742 chip.
+ *
+ * Copyright (C) 2000-2001 Toshiba Corporation 
+ *
+ *  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.
+ *
+ *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
+ *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
+ *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
+ *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
+ *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
+ *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *  You should have received a copy of the  GNU General Public License along
+ *  with this program; if not, write  to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ ***********************************************************************
+ */
+
+
+/*
+ * This file exports a function, rtc_ds1386_init(), which expects an
+ * uncached base address as the argument.  It will set the two function
+ * pointers expected by the MIPS generic timer code.
+ */
+
+#include <linux/types.h>
+#include <linux/time.h>
+#include <linux/rtc.h>
+
+#include <asm/time.h>
+#include <asm/addrspace.h>
+
+#include <asm/jmr3927/ds1742rtc.h>
+#include <asm/debug.h>
+
+#define	EPOCH		2000
+
+#undef BCD_TO_BIN
+#define BCD_TO_BIN(val) (((val)&15) + ((val)>>4)*10)
+
+#undef BIN_TO_BCD
+#define BIN_TO_BCD(val) ((((val)/10)<<4) + (val)%10)
+
+static unsigned long rtc_base;
+
+static unsigned long
+rtc_ds1742_get_time(void)
+{
+	unsigned int year, month, day, hour, minute, second;
+	unsigned int century;
+
+	CMOS_WRITE(RTC_READ, RTC_CONTROL);
+	second = BCD_TO_BIN(CMOS_READ(RTC_SECONDS) & RTC_SECONDS_MASK);
+	minute = BCD_TO_BIN(CMOS_READ(RTC_MINUTES));
+	hour = BCD_TO_BIN(CMOS_READ(RTC_HOURS));
+	day = BCD_TO_BIN(CMOS_READ(RTC_DATE));
+	month = BCD_TO_BIN(CMOS_READ(RTC_MONTH));
+	year = BCD_TO_BIN(CMOS_READ(RTC_YEAR));
+	century = BCD_TO_BIN(CMOS_READ(RTC_CENTURY) & RTC_CENTURY_MASK);
+	CMOS_WRITE(0, RTC_CONTROL);
+
+	year += century * 100;
+
+	return mktime(year, month, day, hour, minute, second);
+}
+extern void to_tm(unsigned long tim, struct rtc_time * tm);
+
+static int 
+rtc_ds1742_set_time(unsigned long t)
+{
+	struct rtc_time tm;
+	u8 year, month, day, hour, minute, second;
+	u8 cmos_year, cmos_month, cmos_day, cmos_hour, cmos_minute, cmos_second;
+	int cmos_century;
+
+	CMOS_WRITE(RTC_READ, RTC_CONTROL);
+	cmos_second = (u8)(CMOS_READ(RTC_SECONDS) & RTC_SECONDS_MASK);
+	cmos_minute = (u8)CMOS_READ(RTC_MINUTES);
+	cmos_hour = (u8)CMOS_READ(RTC_HOURS);
+	cmos_day = (u8)CMOS_READ(RTC_DATE);
+	cmos_month = (u8)CMOS_READ(RTC_MONTH);
+	cmos_year = (u8)CMOS_READ(RTC_YEAR);
+	cmos_century = CMOS_READ(RTC_CENTURY) & RTC_CENTURY_MASK;
+
+	CMOS_WRITE(RTC_WRITE, RTC_CONTROL);
+
+	/* convert */
+	to_tm(t, &tm);
+
+	/* check each field one by one */
+	year = BIN_TO_BCD(tm.tm_year - EPOCH);
+	if (year != cmos_year) {
+		CMOS_WRITE(year,RTC_YEAR);
+	}
+
+	month = BIN_TO_BCD(tm.tm_mon);
+	if (month != (cmos_month & 0x1f)) {
+		CMOS_WRITE((month & 0x1f) | (cmos_month & ~0x1f),RTC_MONTH);
+	}
+
+	day = BIN_TO_BCD(tm.tm_mday);
+	if (day != cmos_day) {
+	
+		CMOS_WRITE(day, RTC_DATE);
+	}
+
+	if (cmos_hour & 0x40) {
+		/* 12 hour format */
+		hour = 0x40;
+		if (tm.tm_hour > 12) {
+			hour |= 0x20 | (BIN_TO_BCD(hour-12) & 0x1f);
+		} else {
+			hour |= BIN_TO_BCD(tm.tm_hour);
+		}
+	} else {
+		/* 24 hour format */
+		hour = BIN_TO_BCD(tm.tm_hour) & 0x3f;
+	}
+	if (hour != cmos_hour) CMOS_WRITE(hour, RTC_HOURS);
+
+	minute = BIN_TO_BCD(tm.tm_min);
+	if (minute !=  cmos_minute) {
+		CMOS_WRITE(minute, RTC_MINUTES);
+	}
+
+	second = BIN_TO_BCD(tm.tm_sec);
+	if (second !=  cmos_second) {
+		CMOS_WRITE(second & RTC_SECONDS_MASK,RTC_SECONDS);
+	}
+	
+	/* RTC_CENTURY and RTC_CONTROL share same address... */
+	CMOS_WRITE(cmos_century, RTC_CONTROL);
+
+	return 0;
+}
+
+void
+rtc_ds1742_init(unsigned long base)
+{
+	u8  cmos_second;
+
+	/* remember the base */
+	rtc_base = base;
+	db_assert((rtc_base & 0xe0000000) == KSEG1);
+
+	/* set the function pointers */
+	rtc_get_time = rtc_ds1742_get_time;
+	rtc_set_time = rtc_ds1742_set_time;
+
+	/* clear oscillator stop bit */
+	CMOS_WRITE(RTC_READ, RTC_CONTROL);
+	cmos_second = (u8)(CMOS_READ(RTC_SECONDS) & RTC_SECONDS_MASK);
+	CMOS_WRITE(RTC_WRITE, RTC_CONTROL);
+	CMOS_WRITE(cmos_second, RTC_SECONDS); /* clear msb */
+	CMOS_WRITE(0, RTC_CONTROL);
+}