LXR uboot/drivers/rtc/max6900.c

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