LXR uboot/drivers/rtc/mc13783-rtc.c

   1/*
   2 * Copyright (C) 2008, Guennadi Liakhovetski <lg@denx.de>
   3 *
   4 * See file CREDITS for list of people who contributed to this
   5 * project.
   6 *
   7 * This program is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public License as
   9 * published by the Free Software Foundation; either version 2 of
  10 * the License, or (at your option) any later version.
  11 *
  12 * This program is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU General Public License
  18 * along with this program; if not, write to the Free Software
  19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  20 * MA 02111-1307 USA
  21 */
  22
  23#include <common.h>
  24#include <rtc.h>
  25#include <spi.h>
  26
  27static struct spi_slave *slave;
  28
  29int rtc_get(struct rtc_time *rtc)
  30{
  31        u32 day1, day2, time;
  32        u32 reg;
  33        int err, tim, i = 0;
  34
  35        if (!slave) {
  36                /* FIXME: Verify the max SCK rate */
  37                slave = spi_setup_slave(CONFIG_MC13783_SPI_BUS,
  38                                CONFIG_MC13783_SPI_CS, 1000000,
  39                                SPI_MODE_2 | SPI_CS_HIGH);
  40                if (!slave)
  41                        return -1;
  42        }
  43
  44        if (spi_claim_bus(slave))
  45                return -1;
  46
  47        do {
  48                reg = 0x2c000000;
  49                err = spi_xfer(slave, 32, (uchar *)&reg, (uchar *)&day1,
  50                                SPI_XFER_BEGIN | SPI_XFER_END);
  51
  52                if (err)
  53                        return err;
  54
  55                reg = 0x28000000;
  56                err = spi_xfer(slave, 32, (uchar *)&reg, (uchar *)&time,
  57                                SPI_XFER_BEGIN | SPI_XFER_END);
  58
  59                if (err)
  60                        return err;
  61
  62                reg = 0x2c000000;
  63                err = spi_xfer(slave, 32, (uchar *)&reg, (uchar *)&day2,
  64                                SPI_XFER_BEGIN | SPI_XFER_END);
  65
  66                if (err)
  67                        return err;
  68        } while (day1 != day2 && i++ < 3);
  69
  70        spi_release_bus(slave);
  71
  72        tim = day1 * 86400 + time;
  73        to_tm(tim, rtc);
  74
  75        rtc->tm_yday = 0;
  76        rtc->tm_isdst = 0;
  77
  78        return 0;
  79}
  80
  81int rtc_set(struct rtc_time *rtc)
  82{
  83        u32 time, day, reg;
  84
  85        if (!slave) {
  86                /* FIXME: Verify the max SCK rate */
  87                slave = spi_setup_slave(CONFIG_MC13783_SPI_BUS,
  88                                CONFIG_MC13783_SPI_CS, 1000000,
  89                                SPI_MODE_2 | SPI_CS_HIGH);
  90                if (!slave)
  91                        return -1;
  92        }
  93
  94        time = mktime(rtc->tm_year, rtc->tm_mon, rtc->tm_mday,
  95                      rtc->tm_hour, rtc->tm_min, rtc->tm_sec);
  96        day = time / 86400;
  97        time %= 86400;
  98
  99        if (spi_claim_bus(slave))
 100                return -1;
 101
 102        reg = 0x2c000000 | day | 0x80000000;
 103        spi_xfer(slave, 32, (uchar *)&reg, (uchar *)&day,
 104                        SPI_XFER_BEGIN | SPI_XFER_END);
 105
 106        reg = 0x28000000 | time | 0x80000000;
 107        spi_xfer(slave, 32, (uchar *)&reg, (uchar *)&time,
 108                        SPI_XFER_BEGIN | SPI_XFER_END);
 109
 110        spi_release_bus(slave);
 111
 112        return -1;
 113}
 114
 115void rtc_reset(void)
 116{
 117}
 118