1 /* 2 * (C) Copyright 2010 3 * Heiko Schocher, DENX Software Engineering, hs@denx.de 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 #include <common.h> 24 #include <command.h> 25 #include <i2c.h> 26 #include <rtc.h> 27 28 #define RTC_RV3029_CTRL1 0x00 29 #define RTC_RV3029_CTRL1_EERE (1 << 3) 30 31 #define RTC_RV3029_CTRL_STATUS 0x03 32 #define RTC_RV3029_CTRLS_EEBUSY (1 << 7) 33 34 #define RTC_RV3029_CTRL_RESET 0x04 35 #define RTC_RV3029_CTRL_SYS_R (1 << 4) 36 37 #define RTC_RV3029_CLOCK_PAGE 0x08 38 #define RTC_RV3029_PAGE_LEN 7 39 40 #define RV3029C2_W_SECONDS 0x00 41 #define RV3029C2_W_MINUTES 0x01 42 #define RV3029C2_W_HOURS 0x02 43 #define RV3029C2_W_DATE 0x03 44 #define RV3029C2_W_DAYS 0x04 45 #define RV3029C2_W_MONTHS 0x05 46 #define RV3029C2_W_YEARS 0x06 47 48 #define RV3029C2_REG_HR_12_24 (1 << 6) /* 24h/12h mode */ 49 #define RV3029C2_REG_HR_PM (1 << 5) /* PM/AM bit in 12h mode */ 50 51 #define RTC_RV3029_EEPROM_CTRL 0x30 52 #define RTC_RV3029_TRICKLE_1K (1 << 4) 53 #define RTC_RV3029_TRICKLE_5K (1 << 5) 54 #define RTC_RV3029_TRICKLE_20K (1 << 6) 55 #define RTC_RV3029_TRICKLE_80K (1 << 7) 56 57 int rtc_get( struct rtc_time *tmp ) 58 { 59 int ret; 60 unsigned char buf[RTC_RV3029_PAGE_LEN]; 61 62 ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CLOCK_PAGE, 1, buf, \ 63 RTC_RV3029_PAGE_LEN); 64 if (ret) { 65 printf("%s: error reading RTC: %x\n", __func__, ret); 66 return -1; 67 } 68 tmp->tm_sec = bcd2bin( buf[RV3029C2_W_SECONDS] & 0x7f); 69 tmp->tm_min = bcd2bin( buf[RV3029C2_W_MINUTES] & 0x7f); 70 if (buf[RV3029C2_W_HOURS] & RV3029C2_REG_HR_12_24) { 71 /* 12h format */ 72 tmp->tm_hour = bcd2bin(buf[RV3029C2_W_HOURS] & 0x1f); 73 if (buf[RV3029C2_W_HOURS] & RV3029C2_REG_HR_PM) 74 /* PM flag set */ 75 tmp->tm_hour += 12; 76 } else 77 tmp->tm_hour = bcd2bin(buf[RV3029C2_W_HOURS] & 0x3f); 78 79 tmp->tm_mday = bcd2bin( buf[RV3029C2_W_DATE] & 0x3F ); 80 tmp->tm_mon = bcd2bin( buf[RV3029C2_W_MONTHS] & 0x1F ); 81 tmp->tm_wday = bcd2bin( buf[RV3029C2_W_DAYS] & 0x07 ); 82 /* RTC supports only years > 1999 */ 83 tmp->tm_year = bcd2bin( buf[RV3029C2_W_YEARS]) + 2000; 84 tmp->tm_yday = 0; 85 tmp->tm_isdst = 0; 86 87 debug( "Get 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 return 0; 92 } 93 94 int rtc_set( struct rtc_time *tmp ) 95 { 96 int ret; 97 unsigned char buf[RTC_RV3029_PAGE_LEN]; 98 99 debug( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 100 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 101 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 102 103 if (tmp->tm_year < 2000) { 104 printf("RTC: year %d < 2000 not possible\n", tmp->tm_year); 105 return -1; 106 } 107 buf[RV3029C2_W_SECONDS] = bin2bcd(tmp->tm_sec); 108 buf[RV3029C2_W_MINUTES] = bin2bcd(tmp->tm_min); 109 buf[RV3029C2_W_HOURS] = bin2bcd(tmp->tm_hour); 110 /* set 24h format */ 111 buf[RV3029C2_W_HOURS] &= ~RV3029C2_REG_HR_12_24; 112 buf[RV3029C2_W_DATE] = bin2bcd(tmp->tm_mday); 113 buf[RV3029C2_W_DAYS] = bin2bcd(tmp->tm_wday); 114 buf[RV3029C2_W_MONTHS] = bin2bcd(tmp->tm_mon); 115 tmp->tm_year -= 2000; 116 buf[RV3029C2_W_YEARS] = bin2bcd(tmp->tm_year); 117 ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CLOCK_PAGE, 1, 118 buf, RTC_RV3029_PAGE_LEN); 119 120 /* give the RTC some time to update */ 121 udelay(1000); 122 return ret; 123 } 124 125 /* sets EERE-Bit (automatic EEPROM refresh) */ 126 static void set_eere_bit(int state) 127 { 128 unsigned char reg_ctrl1; 129 130 (void)i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1, 131 ®_ctrl1, 1); 132 133 if (state) 134 reg_ctrl1 |= RTC_RV3029_CTRL1_EERE; 135 else 136 reg_ctrl1 &= (~RTC_RV3029_CTRL1_EERE); 137 138 (void)i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1, 139 ®_ctrl1, 1); 140 } 141 142 /* waits until EEPROM page is no longer busy (times out after 10ms*loops) */ 143 static int wait_eebusy(int loops) 144 { 145 int i; 146 unsigned char ctrl_status; 147 148 for (i = 0; i < loops; i++) { 149 (void)i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_STATUS, 150 1, &ctrl_status, 1); 151 152 if ((ctrl_status & RTC_RV3029_CTRLS_EEBUSY) == 0) 153 break; 154 udelay(10000); 155 } 156 return i; 157 } 158 159 void rtc_reset (void) 160 { 161 unsigned char buf[RTC_RV3029_PAGE_LEN]; 162 163 buf[0] = RTC_RV3029_CTRL_SYS_R; 164 (void)i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_RESET, 1, 165 buf, 1); 166 167 #if defined(CONFIG_SYS_RV3029_TCR) 168 /* 169 * because EEPROM_CTRL register is in EEPROM page it is necessary to 170 * disable automatic EEPROM refresh and check if EEPROM is busy 171 * before EEPORM_CTRL register may be accessed 172 */ 173 set_eere_bit(0); 174 wait_eebusy(100); 175 /* read current trickle charger setting */ 176 (void)i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_EEPROM_CTRL, 177 1, buf, 1); 178 /* enable automatic EEPROM refresh again */ 179 set_eere_bit(1); 180 181 /* 182 * to minimize EEPROM access write trickle charger setting only if it 183 * differs from current value 184 */ 185 if ((buf[0] & 0xF0) != CONFIG_SYS_RV3029_TCR) { 186 buf[0] = (buf[0] & 0x0F) | CONFIG_SYS_RV3029_TCR; 187 /* 188 * write trickle charger setting (disable autom. EEPROM 189 * refresh and wait until EEPROM is idle) 190 */ 191 set_eere_bit(0); 192 wait_eebusy(100); 193 (void)i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 194 RTC_RV3029_EEPROM_CTRL, 1, buf, 1); 195 /* 196 * it is necessary to wait 10ms before EEBUSY-Bit may be read 197 * (this is not documented in the data sheet yet, but the 198 * manufacturer recommends it) 199 */ 200 udelay(10000); 201 /* wait until EEPROM write access is finished */ 202 wait_eebusy(100); 203 set_eere_bit(1); 204 } 205 #endif 206 } 207