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/*-
* Copyright (c) 2006 Sam Leffler. 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 ``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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Dallas Semiconductor DS1672 RTC sitting on the I2C bus.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/clock.h>
#include <sys/time.h>
#include <sys/bus.h>
#include <sys/resource.h>
#include <sys/rman.h>
#include <dev/iicbus/iiconf.h>
#include "iicbus_if.h"
#include "clock_if.h"
#define IIC_M_WR 0 /* write operation */
#define DS1672_ADDR 0xd0 /* slave address */
#define DS1672_COUNTER 0 /* counter (bytes 0-3) */
#define DS1672_CTRL 4 /* control (1 byte) */
#define DS1672_TRICKLE 5 /* trickle charger (1 byte) */
#define DS1672_CTRL_EOSC (1 << 7) /* Stop/start flag. */
#define NANOSEC 1000000000
#define MAX_IIC_DATA_SIZE 4
struct ds1672_softc {
device_t sc_dev;
};
static int
ds1672_probe(device_t dev)
{
/* XXX really probe? */
device_set_desc(dev, "Dallas Semiconductor DS1672 RTC");
return (BUS_PROBE_NOWILDCARD);
}
static int
ds1672_read(device_t dev, uint8_t addr, uint8_t *data, uint8_t size)
{
struct iic_msg msgs[2] = {
{ DS1672_ADDR, IIC_M_WR, 1, &addr },
{ DS1672_ADDR, IIC_M_RD, size, data }
};
return (iicbus_transfer(dev, msgs, 2));
}
static int
ds1672_write(device_t dev, uint8_t addr, uint8_t *data, uint8_t size)
{
uint8_t buffer[MAX_IIC_DATA_SIZE + 1];
struct iic_msg msgs[1] = {
{ DS1672_ADDR, IIC_M_WR, size + 1, buffer },
};
if (size > MAX_IIC_DATA_SIZE)
return (ENOMEM);
/* NB: register pointer precedes actual data */
buffer[0] = addr;
memcpy(buffer + 1, data, size);
return (iicbus_transfer(dev, msgs, 1));
}
static int
ds1672_init(device_t dev)
{
uint8_t ctrl;
int error;
error = ds1672_read(dev, DS1672_CTRL, &ctrl, 1);
if (error)
return (error);
/*
* Check if oscialltor is not runned.
*/
if (ctrl & DS1672_CTRL_EOSC) {
device_printf(dev, "RTC oscillator was stopped. Check system"
" time and RTC battery.\n");
ctrl &= ~DS1672_CTRL_EOSC; /* Start oscillator. */
error = ds1672_write(dev, DS1672_CTRL, &ctrl, 1);
}
return (error);
}
static int
ds1672_attach(device_t dev)
{
struct ds1672_softc *sc = device_get_softc(dev);
int error;
sc->sc_dev = dev;
error = ds1672_init(dev);
if (error)
return (error);
clock_register(dev, 1000);
return (0);
}
static int
ds1672_gettime(device_t dev, struct timespec *ts)
{
uint8_t secs[4];
int error;
error = ds1672_read(dev, DS1672_COUNTER, secs, 4);
if (error == 0) {
/* counter has seconds since epoch */
ts->tv_sec = (secs[3] << 24) | (secs[2] << 16)
| (secs[1] << 8) | (secs[0] << 0);
ts->tv_nsec = NANOSEC / 2;
}
return (error);
}
static int
ds1672_settime(device_t dev, struct timespec *ts)
{
uint8_t data[4];
data[0] = (ts->tv_sec >> 0) & 0xff;
data[1] = (ts->tv_sec >> 8) & 0xff;
data[2] = (ts->tv_sec >> 16) & 0xff;
data[3] = (ts->tv_sec >> 24) & 0xff;
return (ds1672_write(dev, DS1672_COUNTER, data, 4));
}
static device_method_t ds1672_methods[] = {
DEVMETHOD(device_probe, ds1672_probe),
DEVMETHOD(device_attach, ds1672_attach),
DEVMETHOD(clock_gettime, ds1672_gettime),
DEVMETHOD(clock_settime, ds1672_settime),
DEVMETHOD_END
};
static driver_t ds1672_driver = {
"ds1672_rtc",
ds1672_methods,
sizeof(struct ds1672_softc),
};
static devclass_t ds1672_devclass;
DRIVER_MODULE(ds1672, iicbus, ds1672_driver, ds1672_devclass, 0, 0);
MODULE_VERSION(ds1672, 1);
MODULE_DEPEND(ds1672, iicbus, 1, 1, 1);
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