LXR uboot/drivers/rtc/isl1208.c

   1/*
   2 * (C) Copyright 2008
   3 * Tor Krill, Excito Elektronik i Skåne , tor@excito.com
   4 *
   5 * Modelled after the ds1337 driver
   6 *
   7 * SPDX-License-Identifier:     GPL-2.0+
   8 */
   9
  10/*
  11 * Date & Time support (no alarms) for Intersil
  12 * ISL1208 Real Time Clock (RTC).
  13 */
  14
  15#include <common.h>
  16#include <command.h>
  17#include <rtc.h>
  18#include <i2c.h>
  19
  20/*---------------------------------------------------------------------*/
  21#ifdef DEBUG_RTC
  22#define DEBUGR(fmt,args...) printf(fmt ,##args)
  23#else
  24#define DEBUGR(fmt,args...)
  25#endif
  26/*---------------------------------------------------------------------*/
  27
  28/*
  29 * RTC register addresses
  30 */
  31
  32#define RTC_SEC_REG_ADDR        0x0
  33#define RTC_MIN_REG_ADDR        0x1
  34#define RTC_HR_REG_ADDR         0x2
  35#define RTC_DATE_REG_ADDR       0x3
  36#define RTC_MON_REG_ADDR        0x4
  37#define RTC_YR_REG_ADDR         0x5
  38#define RTC_DAY_REG_ADDR        0x6
  39#define RTC_STAT_REG_ADDR       0x7
  40/*
  41 * RTC control register bits
  42 */
  43
  44/*
  45 * RTC status register bits
  46 */
  47#define RTC_STAT_BIT_ARST       0x80    /* AUTO RESET ENABLE BIT */
  48#define RTC_STAT_BIT_XTOSCB     0x40    /* CRYSTAL OSCILLATOR ENABLE BIT */
  49#define RTC_STAT_BIT_WRTC       0x10    /* WRITE RTC ENABLE BIT */
  50#define RTC_STAT_BIT_ALM        0x04    /* ALARM BIT */
  51#define RTC_STAT_BIT_BAT        0x02    /* BATTERY BIT */
  52#define RTC_STAT_BIT_RTCF       0x01    /* REAL TIME CLOCK FAIL BIT */
  53
  54static uchar rtc_read (uchar reg);
  55static void rtc_write (uchar reg, uchar val);
  56
  57/*
  58 * Get the current time from the RTC
  59 */
  60
  61int rtc_get (struct rtc_time *tmp)
  62{
  63        int rel = 0;
  64        uchar sec, min, hour, mday, wday, mon, year, status;
  65
  66        status = rtc_read (RTC_STAT_REG_ADDR);
  67        sec = rtc_read (RTC_SEC_REG_ADDR);
  68        min = rtc_read (RTC_MIN_REG_ADDR);
  69        hour = rtc_read (RTC_HR_REG_ADDR);
  70        wday = rtc_read (RTC_DAY_REG_ADDR);
  71        mday = rtc_read (RTC_DATE_REG_ADDR);
  72        mon = rtc_read (RTC_MON_REG_ADDR);
  73        year = rtc_read (RTC_YR_REG_ADDR);
  74
  75        DEBUGR ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x "
  76                "hr: %02x min: %02x sec: %02x status: %02x\n",
  77                year, mon, mday, wday, hour, min, sec, status);
  78
  79        if (status & RTC_STAT_BIT_RTCF) {
  80                printf ("### Warning: RTC oscillator has stopped\n");
  81                rtc_write(RTC_STAT_REG_ADDR,
  82                        rtc_read(RTC_STAT_REG_ADDR) &~ (RTC_STAT_BIT_BAT|RTC_STAT_BIT_RTCF));
  83                rel = -1;
  84        }
  85
  86        tmp->tm_sec  = bcd2bin (sec & 0x7F);
  87        tmp->tm_min  = bcd2bin (min & 0x7F);
  88        tmp->tm_hour = bcd2bin (hour & 0x3F);
  89        tmp->tm_mday = bcd2bin (mday & 0x3F);
  90        tmp->tm_mon  = bcd2bin (mon & 0x1F);
  91        tmp->tm_year = bcd2bin (year)+2000;
  92        tmp->tm_wday = bcd2bin (wday & 0x07);
  93        tmp->tm_yday = 0;
  94        tmp->tm_isdst= 0;
  95
  96        DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  97                tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  98                tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  99
 100        return rel;
 101}
 102
 103/*
 104 * Set the RTC
 105 */
 106int rtc_set (struct rtc_time *tmp)
 107{
 108        DEBUGR ("Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 109                tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 110                tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 111
 112        /* enable write */
 113        rtc_write(RTC_STAT_REG_ADDR,
 114                rtc_read(RTC_STAT_REG_ADDR) | RTC_STAT_BIT_WRTC);
 115
 116        rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100));
 117        rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon));
 118        rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday));
 119        rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday));
 120        rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour) | 0x80 ); /* 24h clock */
 121        rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min));
 122        rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec));
 123
 124        /* disable write */
 125        rtc_write(RTC_STAT_REG_ADDR,
 126                rtc_read(RTC_STAT_REG_ADDR) & ~RTC_STAT_BIT_WRTC);
 127
 128        return 0;
 129}
 130
 131void rtc_reset (void)
 132{
 133}
 134
 135/*
 136 * Helper functions
 137 */
 138
 139static uchar rtc_read (uchar reg)
 140{
 141        return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg));
 142}
 143
 144static void rtc_write (uchar reg, uchar val)
 145{
 146        i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
 147}
 148