sys/powerpc/mpc85xx/ds1553_core.c

   1 /*-
   2  * Copyright (C) 2006-2008 Semihalf, Grzegorz Bernacki
   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 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
  31 #include <sys/param.h>
  32 #include <sys/systm.h>
  33 #include <sys/bus.h>
  34 #include <sys/clock.h>
  35 #include <sys/lock.h>
  36 #include <sys/mutex.h>
  37
  38 #include <machine/bus.h>
  39
  40 #include <powerpc/mpc85xx/ds1553_reg.h>
  41
  42 static uint8_t ds1553_direct_read(device_t, bus_size_t);
  43 static void ds1553_direct_write(device_t, bus_size_t, uint8_t);
  44
  45 int
  46 ds1553_attach(device_t dev)
  47 {
  48         struct ds1553_softc *sc;
  49         uint8_t sec, flags;
  50
  51         sc = device_get_softc(dev);
  52
  53         if (mtx_initialized(&sc->sc_mtx) == 0) {
  54                 device_printf(dev, "%s: mutex not initialized\n", __func__);
  55                 return (ENXIO);
  56         }
  57
  58         if (sc->sc_read == NULL)
  59                 sc->sc_read = ds1553_direct_read;
  60         if (sc->sc_write == NULL)
  61                 sc->sc_write = ds1553_direct_write;
  62
  63         sc->year_offset = POSIX_BASE_YEAR;
  64
  65         mtx_lock_spin(&sc->sc_mtx);
  66
  67         /* Turn RTC on if it was not on */
  68         sec = (*sc->sc_read)(dev, DS1553_OFF_SECONDS);
  69         if (sec & DS1553_BIT_OSC) {
  70                 sec &= ~(DS1553_BIT_OSC);
  71                 (*sc->sc_write)(dev, DS1553_OFF_SECONDS, sec);
  72         }
  73
  74         /* Low-battery check */
  75         flags = (*sc->sc_read)(dev, DS1553_OFF_FLAGS);
  76         if (flags & DS1553_BIT_BLF)
  77                 device_printf(dev, "voltage-low detected.\n");
  78
  79         mtx_unlock_spin(&sc->sc_mtx);
  80
  81         return (0);
  82 }
  83
  84 /*
  85  * Get time of day and convert it to a struct timespec.
  86  * Return 0 on success, an error number otherwise.
  87  */
  88 int
  89 ds1553_gettime(device_t dev, struct timespec *ts)
  90 {
  91         struct clocktime ct;
  92         struct ds1553_softc *sc;
  93         uint8_t control;
  94
  95         sc = device_get_softc(dev);
  96
  97         mtx_lock_spin(&sc->sc_mtx);
  98
  99         control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_READ;
 100         (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
 101
 102         ct.nsec = 0;
 103         ct.sec = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_SECONDS) &
 104             DS1553_MASK_SECONDS);
 105         ct.min = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MINUTES) &
 106             DS1553_MASK_MINUTES);
 107         ct.hour = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_HOURS) &
 108             DS1553_MASK_HOUR);
 109         ct.dow = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DAYOFWEEK) &
 110             DS1553_MASK_DAYOFWEEK) - 1;
 111         ct.day = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DATE) &
 112             DS1553_MASK_DATE);
 113         ct.mon = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MONTH) &
 114             DS1553_MASK_MONTH);
 115         ct.year = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_YEAR));
 116
 117         control &= ~DS1553_BIT_READ;
 118         (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
 119
 120         ct.year += sc->year_offset;
 121
 122         mtx_unlock_spin(&sc->sc_mtx);
 123
 124         return (clock_ct_to_ts(&ct, ts));
 125 }
 126
 127 /*
 128  * Set the time of day clock based on the value of the struct timespec arg.
 129  * Return 0 on success, an error number otherwise.
 130  */
 131 int
 132 ds1553_settime(device_t dev, struct timespec *ts)
 133 {
 134         struct clocktime ct;
 135         struct ds1553_softc *sc;
 136         uint8_t control;
 137
 138         sc = device_get_softc(dev);
 139         bzero(&ct, sizeof(struct clocktime));
 140
 141         /* Accuracy is only one second. */
 142         if (ts->tv_nsec >= 500000000)
 143                 ts->tv_sec++;
 144         ts->tv_nsec = 0;
 145         clock_ts_to_ct(ts, &ct);
 146
 147         ct.year -= sc->year_offset;
 148
 149         mtx_lock_spin(&sc->sc_mtx);
 150
 151         /* Halt updates to external registers */
 152         control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_WRITE;
 153         (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
 154
 155         (*sc->sc_write)(dev, DS1553_OFF_SECONDS, TOBCD(ct.sec) &
 156             DS1553_MASK_SECONDS);
 157         (*sc->sc_write)(dev, DS1553_OFF_MINUTES, TOBCD(ct.min) &
 158             DS1553_MASK_MINUTES);
 159         (*sc->sc_write)(dev, DS1553_OFF_HOURS, TOBCD(ct.hour) &
 160             DS1553_MASK_HOUR);
 161         (*sc->sc_write)(dev, DS1553_OFF_DAYOFWEEK, TOBCD(ct.dow + 1) &
 162             DS1553_MASK_DAYOFWEEK);
 163         (*sc->sc_write)(dev, DS1553_OFF_DATE, TOBCD(ct.day) &
 164             DS1553_MASK_DATE);
 165         (*sc->sc_write)(dev, DS1553_OFF_MONTH, TOBCD(ct.mon) &
 166             DS1553_MASK_MONTH);
 167         (*sc->sc_write)(dev, DS1553_OFF_YEAR, TOBCD(ct.year));
 168
 169         /* Resume updates to external registers */
 170         control &= ~DS1553_BIT_WRITE;
 171         (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
 172
 173         mtx_unlock_spin(&sc->sc_mtx);
 174
 175         return (0);
 176 }
 177
 178 static uint8_t
 179 ds1553_direct_read(device_t dev, bus_size_t off)
 180 {
 181         struct ds1553_softc *sc;
 182
 183         sc = device_get_softc(dev);
 184         return (bus_space_read_1(sc->sc_bst, sc->sc_bsh, off));
 185 }
 186
 187 static void
 188 ds1553_direct_write(device_t dev, bus_size_t off, uint8_t val)
 189 {
 190         struct ds1553_softc *sc;
 191
 192         sc = device_get_softc(dev);
 193         bus_space_write_1(sc->sc_bst, sc->sc_bsh, off, val);
 194 }