1 /* 2 * (C) Copyright 2007 3 * Matthias Fuchs, esd gmbh, matthias.fuchs@esd-electronics.com. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 /* 9 * Epson RX8025 RTC driver. 10 */ 11 12 #include <common.h> 13 #include <command.h> 14 #include <rtc.h> 15 #include <i2c.h> 16 17 #if defined(CONFIG_CMD_DATE) 18 19 /*---------------------------------------------------------------------*/ 20 #undef DEBUG_RTC 21 22 #ifdef DEBUG_RTC 23 #define DEBUGR(fmt,args...) printf(fmt ,##args) 24 #else 25 #define DEBUGR(fmt,args...) 26 #endif 27 /*---------------------------------------------------------------------*/ 28 29 #ifndef CONFIG_SYS_I2C_RTC_ADDR 30 # define CONFIG_SYS_I2C_RTC_ADDR 0x32 31 #endif 32 33 /* 34 * RTC register addresses 35 */ 36 #define RTC_SEC_REG_ADDR 0x00 37 #define RTC_MIN_REG_ADDR 0x01 38 #define RTC_HR_REG_ADDR 0x02 39 #define RTC_DAY_REG_ADDR 0x03 40 #define RTC_DATE_REG_ADDR 0x04 41 #define RTC_MON_REG_ADDR 0x05 42 #define RTC_YR_REG_ADDR 0x06 43 44 #define RTC_CTL1_REG_ADDR 0x0e 45 #define RTC_CTL2_REG_ADDR 0x0f 46 47 /* 48 * Control register 1 bits 49 */ 50 #define RTC_CTL1_BIT_2412 0x20 51 52 /* 53 * Control register 2 bits 54 */ 55 #define RTC_CTL2_BIT_PON 0x10 56 #define RTC_CTL2_BIT_VDET 0x40 57 #define RTC_CTL2_BIT_XST 0x20 58 #define RTC_CTL2_BIT_VDSL 0x80 59 60 /* 61 * Note: the RX8025 I2C RTC requires register 62 * reads and write to consist of a single bus 63 * cycle. It is not allowed to write the register 64 * address in a first cycle that is terminated by 65 * a STOP condition. The chips needs a 'restart' 66 * sequence (start sequence without a prior stop). 67 * This driver has been written for a 4xx board. 68 * U-Boot's 4xx i2c driver is currently not capable 69 * to generate such cycles to some work arounds 70 * are used. 71 */ 72 73 /* static uchar rtc_read (uchar reg); */ 74 #define rtc_read(reg) buf[((reg) + 1) & 0xf] 75 76 static void rtc_write (uchar reg, uchar val); 77 78 /* 79 * Get the current time from the RTC 80 */ 81 int rtc_get (struct rtc_time *tmp) 82 { 83 int rel = 0; 84 uchar sec, min, hour, mday, wday, mon, year, ctl2; 85 uchar buf[16]; 86 87 if (i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 16)) 88 printf("Error reading from RTC\n"); 89 90 sec = rtc_read(RTC_SEC_REG_ADDR); 91 min = rtc_read(RTC_MIN_REG_ADDR); 92 hour = rtc_read(RTC_HR_REG_ADDR); 93 wday = rtc_read(RTC_DAY_REG_ADDR); 94 mday = rtc_read(RTC_DATE_REG_ADDR); 95 mon = rtc_read(RTC_MON_REG_ADDR); 96 year = rtc_read(RTC_YR_REG_ADDR); 97 98 DEBUGR ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x " 99 "hr: %02x min: %02x sec: %02x\n", 100 year, mon, mday, wday, hour, min, sec); 101 102 /* dump status */ 103 ctl2 = rtc_read(RTC_CTL2_REG_ADDR); 104 if (ctl2 & RTC_CTL2_BIT_PON) { 105 printf("RTC: power-on detected\n"); 106 rel = -1; 107 } 108 109 if (ctl2 & RTC_CTL2_BIT_VDET) { 110 printf("RTC: voltage drop detected\n"); 111 rel = -1; 112 } 113 114 if (!(ctl2 & RTC_CTL2_BIT_XST)) { 115 printf("RTC: oscillator stop detected\n"); 116 rel = -1; 117 } 118 119 tmp->tm_sec = bcd2bin (sec & 0x7F); 120 tmp->tm_min = bcd2bin (min & 0x7F); 121 if (rtc_read(RTC_CTL1_REG_ADDR) & RTC_CTL1_BIT_2412) 122 tmp->tm_hour = bcd2bin (hour & 0x3F); 123 else 124 tmp->tm_hour = bcd2bin (hour & 0x1F) % 12 + 125 ((hour & 0x20) ? 12 : 0); 126 tmp->tm_mday = bcd2bin (mday & 0x3F); 127 tmp->tm_mon = bcd2bin (mon & 0x1F); 128 tmp->tm_year = bcd2bin (year) + ( bcd2bin (year) >= 70 ? 1900 : 2000); 129 tmp->tm_wday = bcd2bin (wday & 0x07); 130 tmp->tm_yday = 0; 131 tmp->tm_isdst= 0; 132 133 DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 134 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 135 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 136 137 return rel; 138 } 139 140 /* 141 * Set the RTC 142 */ 143 int rtc_set (struct rtc_time *tmp) 144 { 145 DEBUGR ("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 if (tmp->tm_year < 1970 || tmp->tm_year > 2069) 150 printf("WARNING: year should be between 1970 and 2069!\n"); 151 152 rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100)); 153 rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon)); 154 rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday)); 155 rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday)); 156 rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour)); 157 rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min)); 158 rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec)); 159 160 rtc_write (RTC_CTL1_REG_ADDR, RTC_CTL1_BIT_2412); 161 162 return 0; 163 } 164 165 /* 166 * Reset the RTC. We setting the date back to 1970-01-01. 167 */ 168 void rtc_reset (void) 169 { 170 struct rtc_time tmp; 171 uchar buf[16]; 172 uchar ctl2; 173 174 if (i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 16)) 175 printf("Error reading from RTC\n"); 176 177 ctl2 = rtc_read(RTC_CTL2_REG_ADDR); 178 ctl2 &= ~(RTC_CTL2_BIT_PON | RTC_CTL2_BIT_VDET); 179 ctl2 |= RTC_CTL2_BIT_XST | RTC_CTL2_BIT_VDSL; 180 rtc_write (RTC_CTL2_REG_ADDR, ctl2); 181 182 tmp.tm_year = 1970; 183 tmp.tm_mon = 1; 184 tmp.tm_mday= 1; 185 tmp.tm_hour = 0; 186 tmp.tm_min = 0; 187 tmp.tm_sec = 0; 188 189 rtc_set(&tmp); 190 191 printf ( "RTC: %4d-%02d-%02d %2d:%02d:%02d UTC\n", 192 tmp.tm_year, tmp.tm_mon, tmp.tm_mday, 193 tmp.tm_hour, tmp.tm_min, tmp.tm_sec); 194 195 return; 196 } 197 198 /* 199 * Helper functions 200 */ 201 static void rtc_write (uchar reg, uchar val) 202 { 203 uchar buf[2]; 204 buf[0] = reg << 4; 205 buf[1] = val; 206 if (i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 2) != 0) 207 printf("Error writing to RTC\n"); 208 209 } 210 211 #endif /* CONFIG_RTC_RX8025 && CONFIG_CMD_DATE */ 212