freebsd-dev/sys/powerpc/mpc85xx/ds1553_core.c
2009-06-22 15:48:47 +00:00

195 lines
5.4 KiB
C

/*-
* Copyright (C) 2006-2008 Semihalf, Grzegorz Bernacki
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 AUTHOR OR CONTRIBUTORS 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.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/clock.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <machine/bus.h>
#include <powerpc/mpc85xx/ds1553_reg.h>
static uint8_t ds1553_direct_read(device_t, bus_size_t);
static void ds1553_direct_write(device_t, bus_size_t, uint8_t);
int
ds1553_attach(device_t dev)
{
struct ds1553_softc *sc;
uint8_t sec, flags;
sc = device_get_softc(dev);
if (mtx_initialized(&sc->sc_mtx) == 0) {
device_printf(dev, "%s: mutex not initialized\n", __func__);
return (ENXIO);
}
if (sc->sc_read == NULL)
sc->sc_read = ds1553_direct_read;
if (sc->sc_write == NULL)
sc->sc_write = ds1553_direct_write;
sc->year_offset = POSIX_BASE_YEAR;
mtx_lock_spin(&sc->sc_mtx);
/* Turn RTC on if it was not on */
sec = (*sc->sc_read)(dev, DS1553_OFF_SECONDS);
if (sec & DS1553_BIT_OSC) {
sec &= ~(DS1553_BIT_OSC);
(*sc->sc_write)(dev, DS1553_OFF_SECONDS, sec);
}
/* Low-battery check */
flags = (*sc->sc_read)(dev, DS1553_OFF_FLAGS);
if (flags & DS1553_BIT_BLF)
device_printf(dev, "voltage-low detected.\n");
mtx_unlock_spin(&sc->sc_mtx);
return (0);
}
/*
* Get time of day and convert it to a struct timespec.
* Return 0 on success, an error number otherwise.
*/
int
ds1553_gettime(device_t dev, struct timespec *ts)
{
struct clocktime ct;
struct ds1553_softc *sc;
uint8_t control;
sc = device_get_softc(dev);
mtx_lock_spin(&sc->sc_mtx);
control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_READ;
(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
ct.nsec = 0;
ct.sec = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_SECONDS) &
DS1553_MASK_SECONDS);
ct.min = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MINUTES) &
DS1553_MASK_MINUTES);
ct.hour = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_HOURS) &
DS1553_MASK_HOUR);
ct.dow = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DAYOFWEEK) &
DS1553_MASK_DAYOFWEEK) - 1;
ct.day = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DATE) &
DS1553_MASK_DATE);
ct.mon = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MONTH) &
DS1553_MASK_MONTH);
ct.year = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_YEAR));
control &= ~DS1553_BIT_READ;
(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
ct.year += sc->year_offset;
mtx_unlock_spin(&sc->sc_mtx);
return (clock_ct_to_ts(&ct, ts));
}
/*
* Set the time of day clock based on the value of the struct timespec arg.
* Return 0 on success, an error number otherwise.
*/
int
ds1553_settime(device_t dev, struct timespec *ts)
{
struct clocktime ct;
struct ds1553_softc *sc;
uint8_t control;
sc = device_get_softc(dev);
bzero(&ct, sizeof(struct clocktime));
/* Accuracy is only one second. */
if (ts->tv_nsec >= 500000000)
ts->tv_sec++;
ts->tv_nsec = 0;
clock_ts_to_ct(ts, &ct);
ct.year -= sc->year_offset;
mtx_lock_spin(&sc->sc_mtx);
/* Halt updates to external registers */
control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_WRITE;
(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
(*sc->sc_write)(dev, DS1553_OFF_SECONDS, TOBCD(ct.sec) &
DS1553_MASK_SECONDS);
(*sc->sc_write)(dev, DS1553_OFF_MINUTES, TOBCD(ct.min) &
DS1553_MASK_MINUTES);
(*sc->sc_write)(dev, DS1553_OFF_HOURS, TOBCD(ct.hour) &
DS1553_MASK_HOUR);
(*sc->sc_write)(dev, DS1553_OFF_DAYOFWEEK, TOBCD(ct.dow + 1) &
DS1553_MASK_DAYOFWEEK);
(*sc->sc_write)(dev, DS1553_OFF_DATE, TOBCD(ct.day) &
DS1553_MASK_DATE);
(*sc->sc_write)(dev, DS1553_OFF_MONTH, TOBCD(ct.mon) &
DS1553_MASK_MONTH);
(*sc->sc_write)(dev, DS1553_OFF_YEAR, TOBCD(ct.year));
/* Resume updates to external registers */
control &= ~DS1553_BIT_WRITE;
(*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
mtx_unlock_spin(&sc->sc_mtx);
return (0);
}
static uint8_t
ds1553_direct_read(device_t dev, bus_size_t off)
{
struct ds1553_softc *sc;
sc = device_get_softc(dev);
return (bus_space_read_1(sc->sc_bst, sc->sc_bsh, off));
}
static void
ds1553_direct_write(device_t dev, bus_size_t off, uint8_t val)
{
struct ds1553_softc *sc;
sc = device_get_softc(dev);
bus_space_write_1(sc->sc_bst, sc->sc_bsh, off, val);
}