freebsd-skq/sys/arm/s3c2xx0/s3c24x0_rtc.c
andrew 1ac6286cc1 Add the s3c24x0 real time clock driver
Approved by:	imp (mentor)
2010-07-22 23:23:39 +00:00

163 lines
4.2 KiB
C

/*
* Copyright (C) 2010 Andrew Turner
* 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 THE 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/bus.h>
#include <sys/time.h>
#include <sys/clock.h>
#include <sys/resource.h>
#include <sys/systm.h>
#include <sys/rman.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <machine/bus.h>
#include <arm/s3c2xx0/s3c24x0reg.h>
#include "clock_if.h"
#define YEAR_BASE 2000
struct s3c2xx0_rtc_softc {
struct resource *mem_res;
};
static int
s3c2xx0_rtc_probe(device_t dev)
{
device_set_desc(dev, "Samsung Integrated RTC");
return (0);
}
static int
s3c2xx0_rtc_attach(device_t dev)
{
struct s3c2xx0_rtc_softc *sc;
int error, rid;
sc = device_get_softc(dev);
error = 0;
rid = 0;
sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid,
RF_ACTIVE);
if (sc->mem_res == NULL) {
error = ENOMEM;
goto out;
}
bus_write_1(sc->mem_res, RTC_RTCCON, RTCCON_RTCEN);
clock_register(dev, 1000000);
out:
return (error);
}
static int
s3c2xx0_rtc_gettime(device_t dev, struct timespec *ts)
{
struct s3c2xx0_rtc_softc *sc;
struct clocktime ct;
#define READ_TIME() do { \
ct.year = YEAR_BASE + FROMBCD(bus_read_1(sc->mem_res, RTC_BCDYEAR)); \
ct.mon = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDMON)); \
ct.dow = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDDAY)); \
ct.day = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDDATE)); \
ct.hour = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDHOUR)); \
ct.min = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDMIN)); \
ct.sec = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDSEC)); \
} while (0)
sc = device_get_softc(dev);
ct.nsec = 0;
READ_TIME();
/*
* Check if we could have read incorrect values
* as the values could have changed.
*/
if (ct.sec == 0) {
READ_TIME();
}
ct.dow = -1;
#undef READ_TIME
return (clock_ct_to_ts(&ct, ts));
}
static int
s3c2xx0_rtc_settime(device_t dev, struct timespec *ts)
{
struct s3c2xx0_rtc_softc *sc;
struct clocktime ct;
sc = device_get_softc(dev);
/* Resolution: 1 sec */
if (ts->tv_nsec >= 500000000)
ts->tv_sec++;
ts->tv_nsec = 0;
clock_ts_to_ct(ts, &ct);
bus_write_1(sc->mem_res, RTC_BCDSEC, TOBCD(ct.sec));
bus_write_1(sc->mem_res, RTC_BCDMIN, TOBCD(ct.min));
bus_write_1(sc->mem_res, RTC_BCDHOUR, TOBCD(ct.hour));
bus_write_1(sc->mem_res, RTC_BCDDATE, TOBCD(ct.day));
bus_write_1(sc->mem_res, RTC_BCDDAY, TOBCD(ct.dow));
bus_write_1(sc->mem_res, RTC_BCDMON, TOBCD(ct.mon));
bus_write_1(sc->mem_res, RTC_BCDYEAR, TOBCD(ct.year - YEAR_BASE));
return (0);
}
static device_method_t s3c2xx0_rtc_methods[] = {
DEVMETHOD(device_probe, s3c2xx0_rtc_probe),
DEVMETHOD(device_attach, s3c2xx0_rtc_attach),
DEVMETHOD(clock_gettime, s3c2xx0_rtc_gettime),
DEVMETHOD(clock_settime, s3c2xx0_rtc_settime),
{ 0, 0 },
};
static driver_t s3c2xx0_rtc_driver = {
"rtc",
s3c2xx0_rtc_methods,
sizeof(struct s3c2xx0_rtc_softc),
};
static devclass_t s3c2xx0_rtc_devclass;
DRIVER_MODULE(s3c2xx0_rtc, s3c24x0, s3c2xx0_rtc_driver, s3c2xx0_rtc_devclass,
0, 0);