diff options
Diffstat (limited to 'arch/mips/jmr3927/common/rtc_ds1742.c')
| -rw-r--r-- | arch/mips/jmr3927/common/rtc_ds1742.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/mips/jmr3927/common/rtc_ds1742.c b/arch/mips/jmr3927/common/rtc_ds1742.c new file mode 100644 index 00000000000..1ae4318e135 --- /dev/null +++ b/arch/mips/jmr3927/common/rtc_ds1742.c @@ -0,0 +1,165 @@ +/* + * 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 <asm/time.h> +#include <asm/addrspace.h> + +#include <asm/jmr3927/ds1742rtc.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; + + 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); + + 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 = 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); + + 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); +} |