drivers/rtc/s3c24x0_rtc.c

   1 /*
   2  * (C) Copyright 2003
   3  * David Müller ELSOFT AG Switzerland. d.mueller@elsoft.ch
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 /*
  25  * Date & Time support for the built-in Samsung S3C24X0 RTC
  26  */
  27
  28 #include <common.h>
  29 #include <command.h>
  30
  31 #if defined(CONFIG_RTC_S3C24X0) && (defined(CONFIG_CMD_DATE))
  32
  33 #if defined(CONFIG_S3C2400)
  34 #include <s3c2400.h>
  35 #elif defined(CONFIG_S3C2410)
  36 #include <s3c2410.h>
  37 #endif
  38
  39 #include <rtc.h>
  40
  41 /*#define       DEBUG*/
  42
  43 typedef enum {
  44         RTC_ENABLE,
  45         RTC_DISABLE
  46 } RTC_ACCESS;
  47
  48
  49 static inline void SetRTC_Access(RTC_ACCESS a)
  50 {
  51         S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
  52         switch (a) {
  53                 case RTC_ENABLE:
  54                         rtc->RTCCON |= 0x01; break;
  55
  56                 case RTC_DISABLE:
  57                         rtc->RTCCON &= ~0x01; break;
  58         }
  59 }
  60
  61 static unsigned bcd2bin (uchar n)
  62 {
  63         return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F));
  64 }
  65
  66 static unsigned char bin2bcd (unsigned int n)
  67 {
  68         return (((n / 10) << 4) | (n % 10));
  69 }
  70
  71 /* ------------------------------------------------------------------------- */
  72
  73 int rtc_get (struct rtc_time *tmp)
  74 {
  75         S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
  76         uchar sec, min, hour, mday, wday, mon, year;
  77         uchar a_sec,a_min, a_hour, a_date, a_mon, a_year, a_armed;
  78
  79         /* enable access to RTC registers */
  80         SetRTC_Access(RTC_ENABLE);
  81
  82         /* read RTC registers */
  83         do {
  84                 sec     = rtc->BCDSEC;
  85                 min     = rtc->BCDMIN;
  86                 hour    = rtc->BCDHOUR;
  87                 mday    = rtc->BCDDATE;
  88                 wday    = rtc->BCDDAY;
  89                 mon     = rtc->BCDMON;
  90                 year    = rtc->BCDYEAR;
  91         } while (sec != rtc->BCDSEC);
  92
  93         /* read ALARM registers */
  94         a_sec   = rtc->ALMSEC;
  95         a_min   = rtc->ALMMIN;
  96         a_hour  = rtc->ALMHOUR;
  97         a_date  = rtc->ALMDATE;
  98         a_mon   = rtc->ALMMON;
  99         a_year  = rtc->ALMYEAR;
 100         a_armed = rtc->RTCALM;
 101
 102         /* disable access to RTC registers */
 103         SetRTC_Access(RTC_DISABLE);
 104
 105 #ifdef RTC_DEBUG
 106         printf ( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
 107                 "hr: %02x min: %02x sec: %02x\n",
 108                 year, mon, mday, wday,
 109                 hour, min, sec);
 110         printf ( "Alarms: %02x: year: %02x month: %02x date: %02x hour: %02x min: %02x sec: %02x\n",
 111                 a_armed,
 112                 a_year, a_mon, a_date,
 113                 a_hour, a_min, a_sec);
 114 #endif
 115
 116         tmp->tm_sec  = bcd2bin(sec  & 0x7F);
 117         tmp->tm_min  = bcd2bin(min  & 0x7F);
 118         tmp->tm_hour = bcd2bin(hour & 0x3F);
 119         tmp->tm_mday = bcd2bin(mday & 0x3F);
 120         tmp->tm_mon  = bcd2bin(mon & 0x1F);
 121         tmp->tm_year = bcd2bin(year);
 122         tmp->tm_wday = bcd2bin(wday & 0x07);
 123         if(tmp->tm_year<70)
 124                 tmp->tm_year+=2000;
 125         else
 126                 tmp->tm_year+=1900;
 127         tmp->tm_yday = 0;
 128         tmp->tm_isdst= 0;
 129 #ifdef RTC_DEBUG
 130         printf ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 131                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 132                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 133 #endif
 134
 135         return 0;
 136 }
 137
 138 void rtc_set (struct rtc_time *tmp)
 139 {
 140         S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
 141         uchar sec, min, hour, mday, wday, mon, year;
 142
 143 #ifdef RTC_DEBUG
 144         printf ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 145                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 146                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 147 #endif
 148         year    = bin2bcd(tmp->tm_year % 100);
 149         mon     = bin2bcd(tmp->tm_mon);
 150         wday    = bin2bcd(tmp->tm_wday);
 151         mday    = bin2bcd(tmp->tm_mday);
 152         hour    = bin2bcd(tmp->tm_hour);
 153         min     = bin2bcd(tmp->tm_min);
 154         sec     = bin2bcd(tmp->tm_sec);
 155
 156         /* enable access to RTC registers */
 157         SetRTC_Access(RTC_ENABLE);
 158
 159         /* write RTC registers */
 160         rtc->BCDSEC     = sec;
 161         rtc->BCDMIN     = min;
 162         rtc->BCDHOUR    = hour;
 163         rtc->BCDDATE    = mday;
 164         rtc->BCDDAY     = wday;
 165         rtc->BCDMON     = mon;
 166         rtc->BCDYEAR    = year;
 167
 168         /* disable access to RTC registers */
 169         SetRTC_Access(RTC_DISABLE);
 170 }
 171
 172 void rtc_reset (void)
 173 {
 174         S3C24X0_RTC * const rtc = S3C24X0_GetBase_RTC();
 175
 176         rtc->RTCCON = (rtc->RTCCON & ~0x06) | 0x08;
 177         rtc->RTCCON &= ~(0x08|0x01);
 178 }
 179
 180 #endif