1 /* 2 * (C) Copyright 2002 3 * Andrew May, Viasat Inc, amay@viasat.com 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation; either version 2 of 8 * the License, or (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 18 * MA 02111-1307 USA 19 */ 20 21 /* 22 * M41T11 Serial Access Timekeeper(R) SRAM 23 * can you believe a trademark on that? 24 */ 25 26 /* #define DEBUG 1 */ 27 28 #include <common.h> 29 #include <command.h> 30 #include <rtc.h> 31 #include <i2c.h> 32 33 /* 34 I Don't have an example config file but this 35 is what should be done. 36 37 #define CONFIG_RTC_M41T11 1 38 #define CFG_I2C_RTC_ADDR 0x68 39 #if 0 40 #define CFG_M41T11_EXT_CENTURY_DATA 41 #else 42 #define CFG_M41T11_BASE_YEAR 2000 43 #endif 44 */ 45 46 #if defined(CONFIG_RTC_M41T11) && defined(CFG_I2C_RTC_ADDR) && defined(CONFIG_CMD_DATE) 47 48 static unsigned bcd2bin (uchar n) 49 { 50 return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F)); 51 } 52 53 static unsigned char bin2bcd (unsigned int n) 54 { 55 return (((n / 10) << 4) | (n % 10)); 56 } 57 58 59 /* ------------------------------------------------------------------------- */ 60 /* 61 these are simple defines for the chip local to here so they aren't too 62 verbose 63 DAY/DATE aren't nice but that is how they are on the data sheet 64 */ 65 #define RTC_SEC_ADDR 0x0 66 #define RTC_MIN_ADDR 0x1 67 #define RTC_HOUR_ADDR 0x2 68 #define RTC_DAY_ADDR 0x3 69 #define RTC_DATE_ADDR 0x4 70 #define RTC_MONTH_ADDR 0x5 71 #define RTC_YEARS_ADDR 0x6 72 73 #define RTC_REG_CNT 7 74 75 #define RTC_CONTROL_ADDR 0x7 76 77 78 #ifndef CFG_M41T11_EXT_CENTURY_DATA 79 80 #define REG_CNT (RTC_REG_CNT+1) 81 82 /* 83 you only get 00-99 for the year we will asume you 84 want from the year 2000 if you don't set the config 85 */ 86 #ifndef CFG_M41T11_BASE_YEAR 87 #define CFG_M41T11_BASE_YEAR 2000 88 #endif 89 90 #else 91 /* we will store extra year info in byte 9*/ 92 #define M41T11_YEAR_DATA 0x8 93 #define M41T11_YEAR_SIZE 1 94 #define REG_CNT (RTC_REG_CNT+1+M41T11_YEAR_SIZE) 95 #endif 96 97 #define M41T11_STORAGE_SZ (64-REG_CNT) 98 99 void rtc_get (struct rtc_time *tmp) 100 { 101 uchar data[RTC_REG_CNT]; 102 103 i2c_read(CFG_I2C_RTC_ADDR, RTC_SEC_ADDR, 1, data, RTC_REG_CNT); 104 105 if( data[RTC_SEC_ADDR] & 0x80 ){ 106 printf( "m41t11 RTC Clock stopped!!!\n" ); 107 } 108 tmp->tm_sec = bcd2bin (data[RTC_SEC_ADDR] & 0x7F); 109 tmp->tm_min = bcd2bin (data[RTC_MIN_ADDR] & 0x7F); 110 tmp->tm_hour = bcd2bin (data[RTC_HOUR_ADDR] & 0x3F); 111 tmp->tm_mday = bcd2bin (data[RTC_DATE_ADDR] & 0x3F); 112 tmp->tm_mon = bcd2bin (data[RTC_MONTH_ADDR]& 0x1F); 113 #ifndef CFG_M41T11_EXT_CENTURY_DATA 114 tmp->tm_year = CFG_M41T11_BASE_YEAR 115 + bcd2bin(data[RTC_YEARS_ADDR]) 116 + ((data[RTC_HOUR_ADDR]&0x40) ? 100 : 0); 117 #else 118 { 119 unsigned char cent; 120 i2c_read(CFG_I2C_RTC_ADDR, M41T11_YEAR_DATA, 1, ¢, M41T11_YEAR_SIZE); 121 if( !(data[RTC_HOUR_ADDR] & 0x80) ){ 122 printf( "m41t11 RTC: cann't keep track of years without CEB set\n" ); 123 } 124 if( (cent & 0x1) != ((data[RTC_HOUR_ADDR]&0x40)>>7) ){ 125 /*century flip store off new year*/ 126 cent += 1; 127 i2c_write(CFG_I2C_RTC_ADDR, M41T11_YEAR_DATA, 1, ¢, M41T11_YEAR_SIZE); 128 } 129 tmp->tm_year =((int)cent*100)+bcd2bin(data[RTC_YEARS_ADDR]); 130 } 131 #endif 132 tmp->tm_wday = bcd2bin (data[RTC_DAY_ADDR] & 0x07); 133 tmp->tm_yday = 0; 134 tmp->tm_isdst= 0; 135 136 debug ( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 137 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 138 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 139 } 140 141 void rtc_set (struct rtc_time *tmp) 142 { 143 uchar data[RTC_REG_CNT]; 144 145 debug ( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 146 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 147 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 148 149 data[RTC_SEC_ADDR] = bin2bcd(tmp->tm_sec) & 0x7F;/*just in case*/ 150 data[RTC_MIN_ADDR] = bin2bcd(tmp->tm_min); 151 data[RTC_HOUR_ADDR] = bin2bcd(tmp->tm_hour) & 0x3F;/*handle cent stuff later*/ 152 data[RTC_DATE_ADDR] = bin2bcd(tmp->tm_mday) & 0x3F; 153 data[RTC_MONTH_ADDR] = bin2bcd(tmp->tm_mon); 154 data[RTC_DAY_ADDR] = bin2bcd(tmp->tm_wday) & 0x07; 155 156 data[RTC_HOUR_ADDR] |= 0x80;/*we will always use CEB*/ 157 158 data[RTC_YEARS_ADDR] = bin2bcd(tmp->tm_year%100);/*same thing either way*/ 159 #ifndef CFG_M41T11_EXT_CENTURY_DATA 160 if( ((tmp->tm_year - CFG_M41T11_BASE_YEAR) > 200) || 161 (tmp->tm_year < CFG_M41T11_BASE_YEAR) ){ 162 printf( "m41t11 RTC setting year out of range!!need recompile\n" ); 163 } 164 data[RTC_HOUR_ADDR] |= (tmp->tm_year - CFG_M41T11_BASE_YEAR) > 100 ? 0x40 : 0; 165 #else 166 { 167 unsigned char cent; 168 cent = tmp->tm_year ? tmp->tm_year / 100 : 0; 169 data[RTC_HOUR_ADDR] |= (cent & 0x1) ? 0x40 : 0; 170 i2c_write(CFG_I2C_RTC_ADDR, M41T11_YEAR_DATA, 1, ¢, M41T11_YEAR_SIZE); 171 } 172 #endif 173 i2c_write(CFG_I2C_RTC_ADDR, RTC_SEC_ADDR, 1, data, RTC_REG_CNT); 174 } 175 176 void rtc_reset (void) 177 { 178 unsigned char val; 179 /* clear all control & status registers */ 180 i2c_read(CFG_I2C_RTC_ADDR, RTC_SEC_ADDR, 1, &val, 1); 181 val = val & 0x7F;/*make sure we are running*/ 182 i2c_write(CFG_I2C_RTC_ADDR, RTC_SEC_ADDR, 1, &val, RTC_REG_CNT); 183 184 i2c_read(CFG_I2C_RTC_ADDR, RTC_CONTROL_ADDR, 1, &val, 1); 185 val = val & 0x3F;/*turn off freq test keep calibration*/ 186 i2c_write(CFG_I2C_RTC_ADDR, RTC_CONTROL_ADDR, 1, &val, 1); 187 } 188 189 int rtc_store(int addr, unsigned char* data, int size) 190 { 191 /*don't let things wrap onto the time on a write*/ 192 if( (addr+size) >= M41T11_STORAGE_SZ ) 193 return 1; 194 return i2c_write( CFG_I2C_RTC_ADDR, REG_CNT+addr, 1, data, size ); 195 } 196 197 int rtc_recall(int addr, unsigned char* data, int size) 198 { 199 return i2c_read( CFG_I2C_RTC_ADDR, REG_CNT+addr, 1, data, size ); 200 } 201 202 #endif 203