1 /* 2 * (C) Copyright 2008 3 * Stefan Roese, DENX Software Engineering, sr@denx.de. 4 * 5 * based on a the Linux rtc-m41t80.c driver which is: 6 * Alexander Bigga <ab@mycable.de>, 2006 (c) mycable GmbH 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 STMicroelectronics M41T62 26 */ 27 28 /* #define DEBUG */ 29 30 #include <common.h> 31 #include <command.h> 32 #include <rtc.h> 33 #include <i2c.h> 34 35 #if defined(CONFIG_CMD_DATE) 36 37 #define M41T62_REG_SSEC 0 38 #define M41T62_REG_SEC 1 39 #define M41T62_REG_MIN 2 40 #define M41T62_REG_HOUR 3 41 #define M41T62_REG_WDAY 4 42 #define M41T62_REG_DAY 5 43 #define M41T62_REG_MON 6 44 #define M41T62_REG_YEAR 7 45 #define M41T62_REG_ALARM_MON 0xa 46 #define M41T62_REG_ALARM_DAY 0xb 47 #define M41T62_REG_ALARM_HOUR 0xc 48 #define M41T62_REG_ALARM_MIN 0xd 49 #define M41T62_REG_ALARM_SEC 0xe 50 #define M41T62_REG_FLAGS 0xf 51 52 #define M41T62_DATETIME_REG_SIZE (M41T62_REG_YEAR + 1) 53 #define M41T62_ALARM_REG_SIZE \ 54 (M41T62_REG_ALARM_SEC + 1 - M41T62_REG_ALARM_MON) 55 56 #define M41T62_SEC_ST (1 << 7) /* ST: Stop Bit */ 57 #define M41T62_ALMON_AFE (1 << 7) /* AFE: AF Enable Bit */ 58 #define M41T62_ALMON_SQWE (1 << 6) /* SQWE: SQW Enable Bit */ 59 #define M41T62_ALHOUR_HT (1 << 6) /* HT: Halt Update Bit */ 60 #define M41T62_FLAGS_AF (1 << 6) /* AF: Alarm Flag Bit */ 61 #define M41T62_FLAGS_BATT_LOW (1 << 4) /* BL: Battery Low Bit */ 62 63 #define M41T62_FEATURE_HT (1 << 0) 64 #define M41T62_FEATURE_BL (1 << 1) 65 66 #define M41T80_ALHOUR_HT (1 << 6) /* HT: Halt Update Bit */ 67 68 int rtc_get(struct rtc_time *tm) 69 { 70 u8 buf[M41T62_DATETIME_REG_SIZE]; 71 72 i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, buf, M41T62_DATETIME_REG_SIZE); 73 74 debug("%s: raw read data - sec=%02x, min=%02x, hr=%02x, " 75 "mday=%02x, mon=%02x, year=%02x, wday=%02x, y2k=%02x\n", 76 __FUNCTION__, 77 buf[0], buf[1], buf[2], buf[3], 78 buf[4], buf[5], buf[6], buf[7]); 79 80 tm->tm_sec = bcd2bin(buf[M41T62_REG_SEC] & 0x7f); 81 tm->tm_min = bcd2bin(buf[M41T62_REG_MIN] & 0x7f); 82 tm->tm_hour = bcd2bin(buf[M41T62_REG_HOUR] & 0x3f); 83 tm->tm_mday = bcd2bin(buf[M41T62_REG_DAY] & 0x3f); 84 tm->tm_wday = buf[M41T62_REG_WDAY] & 0x07; 85 tm->tm_mon = bcd2bin(buf[M41T62_REG_MON] & 0x1f); 86 87 /* assume 20YY not 19YY, and ignore the Century Bit */ 88 /* U-Boot needs to add 1900 here */ 89 tm->tm_year = bcd2bin(buf[M41T62_REG_YEAR]) + 100 + 1900; 90 91 debug("%s: tm is secs=%d, mins=%d, hours=%d, " 92 "mday=%d, mon=%d, year=%d, wday=%d\n", 93 __FUNCTION__, 94 tm->tm_sec, tm->tm_min, tm->tm_hour, 95 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 96 97 return 0; 98 } 99 100 int rtc_set(struct rtc_time *tm) 101 { 102 u8 buf[M41T62_DATETIME_REG_SIZE]; 103 104 debug("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 105 tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday, 106 tm->tm_hour, tm->tm_min, tm->tm_sec); 107 108 i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, buf, M41T62_DATETIME_REG_SIZE); 109 110 /* Merge time-data and register flags into buf[0..7] */ 111 buf[M41T62_REG_SSEC] = 0; 112 buf[M41T62_REG_SEC] = 113 bin2bcd(tm->tm_sec) | (buf[M41T62_REG_SEC] & ~0x7f); 114 buf[M41T62_REG_MIN] = 115 bin2bcd(tm->tm_min) | (buf[M41T62_REG_MIN] & ~0x7f); 116 buf[M41T62_REG_HOUR] = 117 bin2bcd(tm->tm_hour) | (buf[M41T62_REG_HOUR] & ~0x3f) ; 118 buf[M41T62_REG_WDAY] = 119 (tm->tm_wday & 0x07) | (buf[M41T62_REG_WDAY] & ~0x07); 120 buf[M41T62_REG_DAY] = 121 bin2bcd(tm->tm_mday) | (buf[M41T62_REG_DAY] & ~0x3f); 122 buf[M41T62_REG_MON] = 123 bin2bcd(tm->tm_mon) | (buf[M41T62_REG_MON] & ~0x1f); 124 /* assume 20YY not 19YY */ 125 buf[M41T62_REG_YEAR] = bin2bcd(tm->tm_year % 100); 126 127 if (i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, buf, M41T62_DATETIME_REG_SIZE)) { 128 printf("I2C write failed in %s()\n", __func__); 129 return -1; 130 } 131 132 return 0; 133 } 134 135 void rtc_reset(void) 136 { 137 u8 val; 138 139 /* 140 * M41T82: Make sure HT (Halt Update) bit is cleared. 141 * This bit is 0 in M41T62 so its save to clear it always. 142 */ 143 i2c_read(CONFIG_SYS_I2C_RTC_ADDR, M41T62_REG_ALARM_HOUR, 1, &val, 1); 144 val &= ~M41T80_ALHOUR_HT; 145 i2c_write(CONFIG_SYS_I2C_RTC_ADDR, M41T62_REG_ALARM_HOUR, 1, &val, 1); 146 } 147 148 #endif 149