/*
* 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/bcd.h>
#include <linux/types.h>
#include <linux/time.h>
#include <linux/rtc.h>
#include <linux/ds1742rtc.h>
#include <asm/time.h>
#include <asm/addrspace.h>
#include <asm/debug.h>
#define EPOCH 2000
static unsigned long rtc_base;
static unsigned long
rtc_ds1742_get_time(void)
{
unsigned int year, month, day, hour, minute, second;
unsigned int century;
unsigned long flags;
spin_lock_irqsave(&rtc_lock, flags);
CMOS_WRITE(RTC_READ, RTC_CONTROL);
second = BCD2BIN(CMOS_READ(RTC_SECONDS) & RTC_SECONDS_MASK);
minute = BCD2BIN(CMOS_READ(RTC_MINUTES));
hour = BCD2BIN(CMOS_READ(RTC_HOURS));
day = BCD2BIN(CMOS_READ(RTC_DATE));
month = BCD2BIN(CMOS_READ(RTC_MONTH));
year = BCD2BIN(CMOS_READ(RTC_YEAR));
century = BCD2BIN(CMOS_READ(RTC_CENTURY) & RTC_CENTURY_MASK);
CMOS_WRITE(0, RTC_CONTROL);
spin_unlock_irqrestore(&rtc_lock, flags);
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;
unsigned long flags;
spin_lock_irqsave(&rtc_lock, flags);
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 = BIN2BCD(tm.tm_year - EPOCH);
if (year != cmos_year) {
CMOS_WRITE(year,RTC_YEAR);
}
month = BIN2BCD(tm.tm_mon);
if (month != (cmos_month & 0x1f)) {
CMOS_WRITE((month & 0x1f) | (cmos_month & ~0x1f),RTC_MONTH);
}
day = BIN2BCD(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 | (BIN2BCD(hour-12) & 0x1f);
} else {
hour |= BIN2BCD(tm.tm_hour);
}
} else {
/* 24 hour format */
hour = BIN2BCD(tm.tm_hour) & 0x3f;
}
if (hour != cmos_hour) CMOS_WRITE(hour, RTC_HOURS);
minute = BIN2BCD(tm.tm_min);
if (minute != cmos_minute) {
CMOS_WRITE(minute, RTC_MINUTES);
}
second = BIN2BCD(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);
spin_unlock_irqrestore(&rtc_lock, flags);
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_mips_get_time = rtc_ds1742_get_time;
rtc_mips_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);
}
