/*-
* Copyright (c) 2008 Stanislav Sedov <stas@FreeBSD.org>,
* Rafal Jaworowski <raj@FreeBSD.org>,
* Piotr Ziecik <kosmo@semihalf.com>.
* 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 DS133X 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/iicbus.h>
#include <dev/iicbus/iiconf.h>
#include "iicbus_if.h"
#include "clock_if.h"
#define DS133X_DEVNAME "ds133x_rtc"
#define DS133X_ADDR 0xd0 /* slave address */
#define DS133X_DATE_REG 0x0
#define DS133X_CTRL_REG 0x0e
#define DS133X_OSCD_FLAG 0x80
#define DS133X_OSF_FLAG 0x80
#define DS133X_24H_FLAG 0x40 /* 24 hours mode. */
#define DS133X_PM_FLAG 0x20 /* AM/PM bit. */
#define DS133X_CENT_FLAG 0x80 /* Century selector. */
#define DS133X_CENT_SHIFT 7
#define DS1338_REG_CLOCK_HALT 0x00
#define DS1338_REG_CONTROL 0x07
#define DS1338_CLOCK_HALT (1 << 7)
#define DS1338_OSC_STOP (1 << 5)
#define DS1339_REG_CONTROL 0x0E
#define DS1339_REG_STATUS 0x0F
#define DS1339_OSC_STOP (1 << 7)
#define DS1339_ENABLE_OSC (1 << 7)
#define DS1339_BBSQI (1 << 5)
#define HALFSEC 500000000 /* 1/2 of second. */
#define MAX_IIC_DATA_SIZE 7
enum {
DS1337,
DS1338,
DS1339,
};
struct ds133x_softc {
int sc_type;
device_t sc_dev;
};
static int
ds133x_read(device_t dev, uint8_t address, uint8_t *data, uint8_t size)
{
struct iic_msg msg[] = {
{ DS133X_ADDR, IIC_M_WR, 1, &address },
{ DS133X_ADDR, IIC_M_RD, size, data },
};
return (iicbus_transfer(dev, msg, 2));
}
static int
ds133x_write(device_t dev, uint8_t address, uint8_t *data, uint8_t size)
{
uint8_t buffer[MAX_IIC_DATA_SIZE + 1];
struct iic_msg msg[] = {
{ DS133X_ADDR, IIC_M_WR, size + 1, buffer },
};
if (size > MAX_IIC_DATA_SIZE)
return (ENOMEM);
buffer[0] = address;
memcpy(buffer + 1, data, size);
return (iicbus_transfer(dev, msg, 1));
}
static int
ds133x_detect(device_t dev, int *sc_type)
{
int error;
uint8_t reg, orig;
/*
* Check for DS1338. At address 0x0F this chip has RAM, however
* DS1337 and DS1339 have status register. Bits 6-2 in status
* register will be always read as 0.
*/
if ((error = ds133x_read(dev, DS1339_REG_STATUS, ®, 1)))
return (error);
orig = reg;
reg |= 0x7C;
if ((error = ds133x_write(dev, DS1339_REG_STATUS, ®, 1)))
return (error);
if ((error = ds133x_read(dev, DS1339_REG_STATUS, ®, 1)))
return (error);
if ((reg & 0x7C) != 0) {
/* This is DS1338 */
if ((error = ds133x_write(dev, DS1339_REG_STATUS, &orig, 1)))
return (error);
*sc_type = DS1338;
return (0);
}
/*
* Now Check for DS1337. Bit 5 in control register of this chip will be
* allways read as 0. In DS1339 changing of this bit is safe until
* chip is powered up.
*/
if ((error = ds133x_read(dev, DS1339_REG_CONTROL, ®, 1)))
return (error);
orig = reg;
reg |= DS1339_BBSQI;
if ((error = ds133x_write(dev, DS1339_REG_CONTROL, ®, 1)))
return (error);
if ((error = ds133x_read(dev, DS1339_REG_CONTROL, ®, 1)))
return (error);
if ((reg & DS1339_BBSQI) != 0) {
/* This is DS1339 */
if ((error = ds133x_write(dev, DS1339_REG_CONTROL, &orig, 1)))
return (error);
*sc_type = DS1339;
return (0);
}
/* This is DS1337 */
*sc_type = DS1337;
return (0);
}
static int
ds133x_init(device_t dev, uint8_t cs_reg, uint8_t cs_bit, uint8_t osf_reg,
uint8_t osf_bit)
{
int error;
uint8_t reg;
if ((error = ds133x_read(dev, cs_reg, ®, 1)))
return (error);
if (reg & cs_bit) { /* If clock is stopped - start it */
reg &= ~cs_bit;
if ((error = ds133x_write(dev, cs_reg, ®, 1)))
return (error);
}
if ((error = ds133x_read(dev, osf_reg, ®, 1)))
return (error);
if (reg & osf_bit) { /* Clear oscillator stop flag */
device_printf(dev, "RTC oscillator was stopped. Check system"
" time and RTC battery.\n");
reg &= ~osf_bit;
if ((error = ds133x_write(dev, osf_reg, ®, 1)))
return (error);
}
return (0);
}
static void
ds133x_identify(driver_t *driver, device_t parent)
{
if (device_find_child(parent, DS133X_DEVNAME, -1) == NULL)
BUS_ADD_CHILD(parent, 0, DS133X_DEVNAME, -1);
}
static int
ds133x_probe(device_t dev)
{
struct ds133x_softc *sc;
int error;
sc = device_get_softc(dev);
if ((error = ds133x_detect(dev, &sc->sc_type)))
return (error);
switch (sc->sc_type) {
case DS1337:
device_set_desc(dev, "Dallas Semiconductor DS1337 RTC");
break;
case DS1338:
device_set_desc(dev, "Dallas Semiconductor DS1338 RTC");
break;
case DS1339:
device_set_desc(dev, "Dallas Semiconductor DS1339 RTC");
break;
default:
break;
}
return (0);
}
static int
ds133x_attach(device_t dev)
{
struct ds133x_softc *sc = device_get_softc(dev);
sc->sc_dev = dev;
if (sc->sc_type == DS1338)
ds133x_init(dev, DS1338_REG_CLOCK_HALT, DS1338_CLOCK_HALT,
DS1338_REG_CONTROL, DS1338_OSC_STOP);
else
ds133x_init(dev, DS1339_REG_CONTROL, DS1339_ENABLE_OSC,
DS1339_REG_STATUS, DS1339_OSC_STOP);
clock_register(dev, 1000000);
return (0);
}
static uint8_t
ds133x_get_hours(uint8_t val)
{
uint8_t ret;
if (!(val & DS133X_24H_FLAG))
ret = FROMBCD(val & 0x3f);
else if (!(val & DS133X_PM_FLAG))
ret = FROMBCD(val & 0x1f);
else
ret = FROMBCD(val & 0x1f) + 12;
return (ret);
}
static int
ds133x_gettime(device_t dev, struct timespec *ts)
{
struct ds133x_softc *sc = device_get_softc(dev);
struct clocktime ct;
uint8_t date[7];
int error;
error = ds133x_read(dev, DS133X_DATE_REG, date, 7);
if (error == 0) {
ct.nsec = 0;
ct.sec = FROMBCD(date[0] & 0x7f);
ct.min = FROMBCD(date[1] & 0x7f);
ct.hour = ds133x_get_hours(date[2]);
ct.dow = FROMBCD(date[3] & 0x07) - 1;
ct.day = FROMBCD(date[4] & 0x3f);
ct.mon = FROMBCD(date[5] & 0x1f);
if (sc->sc_type == DS1338)
ct.year = 2000 + FROMBCD(date[6]);
else
ct.year = 1900 + FROMBCD(date[6]) +
((date[5] & DS133X_CENT_FLAG) >> DS133X_CENT_SHIFT) * 100;
error = clock_ct_to_ts(&ct, ts);
}
return (error);
}
static int
ds133x_settime(device_t dev, struct timespec *ts)
{
struct ds133x_softc *sc = device_get_softc(dev);
struct clocktime ct;
uint8_t date[7];
clock_ts_to_ct(ts, &ct);
date[0] = TOBCD(ct.nsec >= HALFSEC ? ct.sec + 1 : ct.sec) & 0x7f;
date[1] = TOBCD(ct.min) & 0x7f;
date[2] = TOBCD(ct.hour) & 0x3f; /* We use 24-hours mode. */
date[3] = TOBCD(ct.dow + 1) & 0x07;
date[4] = TOBCD(ct.day) & 0x3f;
date[5] = TOBCD(ct.mon) & 0x1f;
if (sc->sc_type == DS1338)
date[6] = TOBCD(ct.year - 2000);
else if (ct.year >= 2000) {
date[5] |= DS133X_CENT_FLAG;
date[6] = TOBCD(ct.year - 2000);
} else
date[6] = TOBCD(ct.year - 1900);
return (ds133x_write(dev, DS133X_DATE_REG, date, 7));
}
static device_method_t ds133x_methods[] = {
DEVMETHOD(device_identify, ds133x_identify),
DEVMETHOD(device_probe, ds133x_probe),
DEVMETHOD(device_attach, ds133x_attach),
DEVMETHOD(clock_gettime, ds133x_gettime),
DEVMETHOD(clock_settime, ds133x_settime),
{0, 0},
};
static driver_t ds133x_driver = {
DS133X_DEVNAME,
ds133x_methods,
sizeof(struct ds133x_softc),
};
static devclass_t ds133x_devclass;
DRIVER_MODULE(ds133x, iicbus, ds133x_driver, ds133x_devclass, 0, 0);
MODULE_VERSION(ds133x, 1);
MODULE_DEPEND(ds133x, iicbus, 1, 1, 1);
