sys/arm/s3c2xx0/s3c24x0_rtc.c

   1 /*
   2  * Copyright (C) 2010 Andrew Turner
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30 #include <sys/param.h>
  31 #include <sys/bus.h>
  32 #include <sys/time.h>
  33 #include <sys/clock.h>
  34 #include <sys/resource.h>
  35 #include <sys/systm.h>
  36 #include <sys/rman.h>
  37 #include <sys/kernel.h>
  38 #include <sys/module.h>
  39
  40 #include <machine/bus.h>
  41
  42 #include <arm/s3c2xx0/s3c24x0reg.h>
  43
  44 #include "clock_if.h"
  45
  46 #define YEAR_BASE               2000
  47
  48 struct s3c2xx0_rtc_softc {
  49         struct resource *mem_res;
  50 };
  51
  52 static int
  53 s3c2xx0_rtc_probe(device_t dev)
  54 {
  55
  56         device_set_desc(dev, "Samsung Integrated RTC");
  57         return (0);
  58 }
  59
  60 static int
  61 s3c2xx0_rtc_attach(device_t dev)
  62 {
  63         struct s3c2xx0_rtc_softc *sc;
  64         int error, rid;
  65
  66         sc = device_get_softc(dev);
  67         error = 0;
  68
  69         rid = 0;
  70         sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid,
  71             RF_ACTIVE);
  72         if (sc->mem_res == NULL) {
  73                 error = ENOMEM;
  74                 goto out;
  75         }
  76
  77         bus_write_1(sc->mem_res, RTC_RTCCON, RTCCON_RTCEN);
  78         clock_register(dev, 1000000);
  79
  80 out:
  81         return (error);
  82 }
  83
  84 static int
  85 s3c2xx0_rtc_gettime(device_t dev, struct timespec *ts)
  86 {
  87         struct s3c2xx0_rtc_softc *sc;
  88         struct clocktime ct;
  89
  90 #define READ_TIME() do {                                                \
  91         ct.year = YEAR_BASE + FROMBCD(bus_read_1(sc->mem_res, RTC_BCDYEAR)); \
  92         ct.mon = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDMON));          \
  93         ct.dow = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDDAY));          \
  94         ct.day = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDDATE));         \
  95         ct.hour = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDHOUR));        \
  96         ct.min = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDMIN));          \
  97         ct.sec = FROMBCD(bus_read_1(sc->mem_res, RTC_BCDSEC));          \
  98 } while (0)
  99
 100         sc = device_get_softc(dev);
 101
 102         ct.nsec = 0;
 103         READ_TIME();
 104         /*
 105          * Check if we could have read incorrect values
 106          * as the values could have changed.
 107          */
 108         if (ct.sec == 0) {
 109                 READ_TIME();
 110         }
 111
 112         ct.dow = -1;
 113
 114 #undef READ_TIME
 115         return (clock_ct_to_ts(&ct, ts));
 116 }
 117
 118 static int
 119 s3c2xx0_rtc_settime(device_t dev, struct timespec *ts)
 120 {
 121         struct s3c2xx0_rtc_softc *sc;
 122         struct clocktime ct;
 123
 124         sc = device_get_softc(dev);
 125
 126         /* Resolution: 1 sec */
 127         if (ts->tv_nsec >= 500000000)
 128                 ts->tv_sec++;
 129         ts->tv_nsec = 0;
 130         clock_ts_to_ct(ts, &ct);
 131
 132         bus_write_1(sc->mem_res, RTC_BCDSEC, TOBCD(ct.sec));
 133         bus_write_1(sc->mem_res, RTC_BCDMIN, TOBCD(ct.min));
 134         bus_write_1(sc->mem_res, RTC_BCDHOUR, TOBCD(ct.hour));
 135         bus_write_1(sc->mem_res, RTC_BCDDATE, TOBCD(ct.day));
 136         bus_write_1(sc->mem_res, RTC_BCDDAY, TOBCD(ct.dow));
 137         bus_write_1(sc->mem_res, RTC_BCDMON, TOBCD(ct.mon));
 138         bus_write_1(sc->mem_res, RTC_BCDYEAR, TOBCD(ct.year - YEAR_BASE));
 139
 140         return (0);
 141 }
 142
 143 static device_method_t s3c2xx0_rtc_methods[] = {
 144         DEVMETHOD(device_probe,         s3c2xx0_rtc_probe),
 145         DEVMETHOD(device_attach,        s3c2xx0_rtc_attach),
 146
 147         DEVMETHOD(clock_gettime,        s3c2xx0_rtc_gettime),
 148         DEVMETHOD(clock_settime,        s3c2xx0_rtc_settime),
 149
 150         { 0, 0 },
 151 };
 152
 153 static driver_t s3c2xx0_rtc_driver = {
 154         "rtc",
 155         s3c2xx0_rtc_methods,
 156         sizeof(struct s3c2xx0_rtc_softc),
 157 };
 158 static devclass_t s3c2xx0_rtc_devclass;
 159
 160 DRIVER_MODULE(s3c2xx0_rtc, s3c24x0, s3c2xx0_rtc_driver, s3c2xx0_rtc_devclass,
 161     0, 0);
 162