LXR uboot/drivers/rtc/max6900.c

   1/*
   2 * (C) Copyright 2004
   3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4 *
   5 * SPDX-License-Identifier:     GPL-2.0+
   6 */
   7
   8/*
   9 * Date & Time support for MAXIM MAX6900 RTC
  10 */
  11
  12/* #define      DEBUG   */
  13
  14#include <common.h>
  15#include <command.h>
  16#include <rtc.h>
  17#include <i2c.h>
  18
  19#if defined(CONFIG_CMD_DATE)
  20
  21#ifndef CONFIG_SYS_I2C_RTC_ADDR
  22#define CONFIG_SYS_I2C_RTC_ADDR 0x50
  23#endif
  24
  25/* ------------------------------------------------------------------------- */
  26
  27static uchar rtc_read (uchar reg)
  28{
  29        return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg));
  30}
  31
  32static void rtc_write (uchar reg, uchar val)
  33{
  34        i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
  35        udelay(2500);
  36}
  37
  38/* ------------------------------------------------------------------------- */
  39
  40int rtc_get (struct rtc_time *tmp)
  41{
  42        uchar sec, min, hour, mday, wday, mon, cent, year;
  43        int retry = 1;
  44
  45        do {
  46                sec     = rtc_read (0x80);
  47                min     = rtc_read (0x82);
  48                hour    = rtc_read (0x84);
  49                mday    = rtc_read (0x86);
  50                mon     = rtc_read (0x88);
  51                wday    = rtc_read (0x8a);
  52                year    = rtc_read (0x8c);
  53                cent    = rtc_read (0x92);
  54                /*
  55                 * Check for seconds rollover
  56                 */
  57                if ((sec != 59) || (rtc_read(0x80) == sec)){
  58                        retry = 0;
  59                }
  60        } while (retry);
  61
  62        debug ( "Get RTC year: %02x mon: %02x cent: %02x mday: %02x wday: %02x "
  63                "hr: %02x min: %02x sec: %02x\n",
  64                year, mon, cent, mday, wday,
  65                hour, min, sec );
  66
  67        tmp->tm_sec  = bcd2bin (sec  & 0x7F);
  68        tmp->tm_min  = bcd2bin (min  & 0x7F);
  69        tmp->tm_hour = bcd2bin (hour & 0x3F);
  70        tmp->tm_mday = bcd2bin (mday & 0x3F);
  71        tmp->tm_mon  = bcd2bin (mon & 0x1F);
  72        tmp->tm_year = bcd2bin (year) + bcd2bin(cent) * 100;
  73        tmp->tm_wday = bcd2bin (wday & 0x07);
  74        tmp->tm_yday = 0;
  75        tmp->tm_isdst= 0;
  76
  77        debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  78                tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  79                tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  80
  81        return 0;
  82}
  83
  84int rtc_set (struct rtc_time *tmp)
  85{
  86
  87        debug ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  88                tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  89                tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  90
  91        rtc_write (0x9E, 0x00);
  92        rtc_write (0x80, 0);    /* Clear seconds to ensure no rollover */
  93        rtc_write (0x92, bin2bcd(tmp->tm_year / 100));
  94        rtc_write (0x8c, bin2bcd(tmp->tm_year % 100));
  95        rtc_write (0x8a, bin2bcd(tmp->tm_wday));
  96        rtc_write (0x88, bin2bcd(tmp->tm_mon));
  97        rtc_write (0x86, bin2bcd(tmp->tm_mday));
  98        rtc_write (0x84, bin2bcd(tmp->tm_hour));
  99        rtc_write (0x82, bin2bcd(tmp->tm_min ));
 100        rtc_write (0x80, bin2bcd(tmp->tm_sec ));
 101
 102        return 0;
 103}
 104
 105void rtc_reset (void)
 106{
 107}
 108
 109#endif
 110