1 /* 2 * (C) Copyright 2007 3 * Matthias Fuchs, esd gmbh, matthias.fuchs@esd-electronics.com. 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 * Epson RX8025 RTC driver. 26 */ 27 28 #include <common.h> 29 #include <command.h> 30 #include <rtc.h> 31 #include <i2c.h> 32 33 #if defined(CONFIG_RTC_RX8025) && defined(CONFIG_CMD_DATE) 34 35 /*---------------------------------------------------------------------*/ 36 #undef DEBUG_RTC 37 38 #ifdef DEBUG_RTC 39 #define DEBUGR(fmt,args...) printf(fmt ,##args) 40 #else 41 #define DEBUGR(fmt,args...) 42 #endif 43 /*---------------------------------------------------------------------*/ 44 45 #ifndef CFG_I2C_RTC_ADDR 46 # define CFG_I2C_RTC_ADDR 0x32 47 #endif 48 49 /* 50 * RTC register addresses 51 */ 52 #define RTC_SEC_REG_ADDR 0x00 53 #define RTC_MIN_REG_ADDR 0x01 54 #define RTC_HR_REG_ADDR 0x02 55 #define RTC_DAY_REG_ADDR 0x03 56 #define RTC_DATE_REG_ADDR 0x04 57 #define RTC_MON_REG_ADDR 0x05 58 #define RTC_YR_REG_ADDR 0x06 59 60 #define RTC_CTL1_REG_ADDR 0x0e 61 #define RTC_CTL2_REG_ADDR 0x0f 62 63 /* 64 * Control register 1 bits 65 */ 66 #define RTC_CTL1_BIT_2412 0x20 67 68 /* 69 * Control register 2 bits 70 */ 71 #define RTC_CTL2_BIT_PON 0x10 72 #define RTC_CTL2_BIT_VDET 0x40 73 #define RTC_CTL2_BIT_XST 0x20 74 #define RTC_CTL2_BIT_VDSL 0x80 75 76 /* 77 * Note: the RX8025 I2C RTC requires register 78 * reads and write to consist of a single bus 79 * cycle. It is not allowed to write the register 80 * address in a first cycle that is terminated by 81 * a STOP condition. The chips needs a 'restart' 82 * sequence (start sequence without a prior stop). 83 * This driver has been written for a 4xx board. 84 * U-Boot's 4xx i2c driver is currently not capable 85 * to generate such cycles to some work arounds 86 * are used. 87 */ 88 89 /* static uchar rtc_read (uchar reg); */ 90 #define rtc_read(reg) buf[((reg) + 1) & 0xf] 91 92 static void rtc_write (uchar reg, uchar val); 93 static uchar bin2bcd (unsigned int n); 94 static unsigned bcd2bin (uchar c); 95 96 /* 97 * Get the current time from the RTC 98 */ 99 int rtc_get (struct rtc_time *tmp) 100 { 101 int rel = 0; 102 uchar sec, min, hour, mday, wday, mon, year, ctl2; 103 uchar buf[16]; 104 105 if (i2c_read(CFG_I2C_RTC_ADDR, 0, 0, buf, 16)) 106 printf("Error reading from RTC\n"); 107 108 sec = rtc_read(RTC_SEC_REG_ADDR); 109 min = rtc_read(RTC_MIN_REG_ADDR); 110 hour = rtc_read(RTC_HR_REG_ADDR); 111 wday = rtc_read(RTC_DAY_REG_ADDR); 112 mday = rtc_read(RTC_DATE_REG_ADDR); 113 mon = rtc_read(RTC_MON_REG_ADDR); 114 year = rtc_read(RTC_YR_REG_ADDR); 115 116 DEBUGR ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x " 117 "hr: %02x min: %02x sec: %02x\n", 118 year, mon, mday, wday, hour, min, sec); 119 120 /* dump status */ 121 ctl2 = rtc_read(RTC_CTL2_REG_ADDR); 122 if (ctl2 & RTC_CTL2_BIT_PON) { 123 printf("RTC: power-on detected\n"); 124 rel = -1; 125 } 126 127 if (ctl2 & RTC_CTL2_BIT_VDET) { 128 printf("RTC: voltage drop detected\n"); 129 rel = -1; 130 } 131 132 if (!(ctl2 & RTC_CTL2_BIT_XST)) { 133 printf("RTC: oscillator stop detected\n"); 134 rel = -1; 135 } 136 137 tmp->tm_sec = bcd2bin (sec & 0x7F); 138 tmp->tm_min = bcd2bin (min & 0x7F); 139 tmp->tm_hour = bcd2bin (hour & 0x3F); 140 tmp->tm_mday = bcd2bin (mday & 0x3F); 141 tmp->tm_mon = bcd2bin (mon & 0x1F); 142 tmp->tm_year = bcd2bin (year) + ( bcd2bin (year) >= 70 ? 1900 : 2000); 143 tmp->tm_wday = bcd2bin (wday & 0x07); 144 tmp->tm_yday = 0; 145 tmp->tm_isdst= 0; 146 147 DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 148 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 149 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 150 151 return rel; 152 } 153 154 /* 155 * Set the RTC 156 */ 157 void rtc_set (struct rtc_time *tmp) 158 { 159 DEBUGR ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 160 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 161 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 162 163 if (tmp->tm_year < 1970 || tmp->tm_year > 2069) 164 printf("WARNING: year should be between 1970 and 2069!\n"); 165 166 rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100)); 167 rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon)); 168 rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday)); 169 rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday)); 170 rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour)); 171 rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min)); 172 rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec)); 173 174 rtc_write (RTC_CTL1_REG_ADDR, RTC_CTL1_BIT_2412); 175 } 176 177 /* 178 * Reset the RTC. We setting the date back to 1970-01-01. 179 */ 180 void rtc_reset (void) 181 { 182 struct rtc_time tmp; 183 uchar buf[16]; 184 uchar ctl2; 185 186 if (i2c_read(CFG_I2C_RTC_ADDR, 0, 0, buf, 16)) 187 printf("Error reading from RTC\n"); 188 189 ctl2 = rtc_read(RTC_CTL2_REG_ADDR); 190 ctl2 &= ~(RTC_CTL2_BIT_PON | RTC_CTL2_BIT_VDET); 191 ctl2 |= RTC_CTL2_BIT_XST | RTC_CTL2_BIT_VDSL; 192 rtc_write (RTC_CTL2_REG_ADDR, ctl2); 193 194 tmp.tm_year = 1970; 195 tmp.tm_mon = 1; 196 tmp.tm_mday= 1; 197 tmp.tm_hour = 0; 198 tmp.tm_min = 0; 199 tmp.tm_sec = 0; 200 201 rtc_set(&tmp); 202 203 printf ( "RTC: %4d-%02d-%02d %2d:%02d:%02d UTC\n", 204 tmp.tm_year, tmp.tm_mon, tmp.tm_mday, 205 tmp.tm_hour, tmp.tm_min, tmp.tm_sec); 206 207 return; 208 } 209 210 /* 211 * Helper functions 212 */ 213 static void rtc_write (uchar reg, uchar val) 214 { 215 uchar buf[2]; 216 buf[0] = reg << 4; 217 buf[1] = val; 218 if (i2c_write(CFG_I2C_RTC_ADDR, 0, 0, buf, 2) != 0) 219 printf("Error writing to RTC\n"); 220 221 } 222 223 static unsigned bcd2bin (uchar n) 224 { 225 return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F)); 226 } 227 228 static unsigned char bin2bcd (unsigned int n) 229 { 230 return (((n / 10) << 4) | (n % 10)); 231 } 232 233 #endif /* CONFIG_RTC_RX8025 && CONFIG_CMD_DATE */ 234