drivers/rtc/pcf8563.c

   1 /*
   2  * (C) Copyright 2001
   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 Philips PCF8563 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 static uchar rtc_read  (uchar reg);
  22 static void  rtc_write (uchar reg, uchar val);
  23
  24 /* ------------------------------------------------------------------------- */
  25
  26 int rtc_get (struct rtc_time *tmp)
  27 {
  28         int rel = 0;
  29         uchar sec, min, hour, mday, wday, mon_cent, year;
  30
  31         sec     = rtc_read (0x02);
  32         min     = rtc_read (0x03);
  33         hour    = rtc_read (0x04);
  34         mday    = rtc_read (0x05);
  35         wday    = rtc_read (0x06);
  36         mon_cent= rtc_read (0x07);
  37         year    = rtc_read (0x08);
  38
  39         debug ( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
  40                 "hr: %02x min: %02x sec: %02x\n",
  41                 year, mon_cent, mday, wday,
  42                 hour, min, sec );
  43         debug ( "Alarms: wday: %02x day: %02x hour: %02x min: %02x\n",
  44                 rtc_read (0x0C),
  45                 rtc_read (0x0B),
  46                 rtc_read (0x0A),
  47                 rtc_read (0x09) );
  48
  49         if (sec & 0x80) {
  50                 puts ("### Warning: RTC Low Voltage - date/time not reliable\n");
  51                 rel = -1;
  52         }
  53
  54         tmp->tm_sec  = bcd2bin (sec  & 0x7F);
  55         tmp->tm_min  = bcd2bin (min  & 0x7F);
  56         tmp->tm_hour = bcd2bin (hour & 0x3F);
  57         tmp->tm_mday = bcd2bin (mday & 0x3F);
  58         tmp->tm_mon  = bcd2bin (mon_cent & 0x1F);
  59         tmp->tm_year = bcd2bin (year) + ((mon_cent & 0x80) ? 1900 : 2000);
  60         tmp->tm_wday = bcd2bin (wday & 0x07);
  61         tmp->tm_yday = 0;
  62         tmp->tm_isdst= 0;
  63
  64         debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  65                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  66                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  67
  68         return rel;
  69 }
  70
  71 int rtc_set (struct rtc_time *tmp)
  72 {
  73         uchar century;
  74
  75         debug ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  76                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  77                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  78
  79         rtc_write (0x08, bin2bcd(tmp->tm_year % 100));
  80
  81         century = (tmp->tm_year >= 2000) ? 0 : 0x80;
  82         rtc_write (0x07, bin2bcd(tmp->tm_mon) | century);
  83
  84         rtc_write (0x06, bin2bcd(tmp->tm_wday));
  85         rtc_write (0x05, bin2bcd(tmp->tm_mday));
  86         rtc_write (0x04, bin2bcd(tmp->tm_hour));
  87         rtc_write (0x03, bin2bcd(tmp->tm_min ));
  88         rtc_write (0x02, bin2bcd(tmp->tm_sec ));
  89
  90         return 0;
  91 }
  92
  93 void rtc_reset (void)
  94 {
  95         /* clear all control & status registers */
  96         rtc_write (0x00, 0x00);
  97         rtc_write (0x01, 0x00);
  98         rtc_write (0x0D, 0x00);
  99
 100         /* clear Voltage Low bit */
 101         rtc_write (0x02, rtc_read (0x02) & 0x7F);
 102
 103         /* reset all alarms */
 104         rtc_write (0x09, 0x00);
 105         rtc_write (0x0A, 0x00);
 106         rtc_write (0x0B, 0x00);
 107         rtc_write (0x0C, 0x00);
 108 }
 109
 110 /* ------------------------------------------------------------------------- */
 111
 112 static uchar rtc_read (uchar reg)
 113 {
 114         return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg));
 115 }
 116
 117 static void rtc_write (uchar reg, uchar val)
 118 {
 119         i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
 120 }
 121
 122 #endif