1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2007 4 * Matthias Fuchs, esd gmbh, matthias.fuchs (at) esd-electronics.com. 5 */ 6 7 /* 8 * Epson RX8025 RTC driver. 9 */ 10 11 #include <common.h> 12 #include <command.h> 13 #include <rtc.h> 14 #include <i2c.h> 15 16 #if defined(CONFIG_CMD_DATE) 17 18 /*---------------------------------------------------------------------*/ 19 #undef DEBUG_RTC 20 21 #ifdef DEBUG_RTC 22 #define DEBUGR(fmt,args...) printf(fmt ,##args) 23 #else 24 #define DEBUGR(fmt,args...) 25 #endif 26 /*---------------------------------------------------------------------*/ 27 28 #ifndef CONFIG_SYS_I2C_RTC_ADDR 29 # define CONFIG_SYS_I2C_RTC_ADDR 0x32 30 #endif 31 32 /* 33 * RTC register addresses 34 */ 35 #define RTC_SEC_REG_ADDR 0x00 36 #define RTC_MIN_REG_ADDR 0x01 37 #define RTC_HR_REG_ADDR 0x02 38 #define RTC_DAY_REG_ADDR 0x03 39 #define RTC_DATE_REG_ADDR 0x04 40 #define RTC_MON_REG_ADDR 0x05 41 #define RTC_YR_REG_ADDR 0x06 42 43 #define RTC_CTL1_REG_ADDR 0x0e 44 #define RTC_CTL2_REG_ADDR 0x0f 45 46 /* 47 * Control register 1 bits 48 */ 49 #define RTC_CTL1_BIT_2412 0x20 50 51 /* 52 * Control register 2 bits 53 */ 54 #define RTC_CTL2_BIT_PON 0x10 55 #define RTC_CTL2_BIT_VDET 0x40 56 #define RTC_CTL2_BIT_XST 0x20 57 #define RTC_CTL2_BIT_VDSL 0x80 58 59 /* 60 * Note: the RX8025 I2C RTC requires register 61 * reads and write to consist of a single bus 62 * cycle. It is not allowed to write the register 63 * address in a first cycle that is terminated by 64 * a STOP condition. The chips needs a 'restart' 65 * sequence (start sequence without a prior stop). 66 * This driver has been written for a 4xx board. 67 * U-Boot's 4xx i2c driver is currently not capable 68 * to generate such cycles to some work arounds 69 * are used. 70 */ 71 72 /* static uchar rtc_read (uchar reg); */ 73 #define rtc_read(reg) buf[((reg) + 1) & 0xf] 74 75 static void rtc_write (uchar reg, uchar val); 76 77 /* 78 * Get the current time from the RTC 79 */ 80 int rtc_get (struct rtc_time *tmp) 81 { 82 int rel = 0; 83 uchar sec, min, hour, mday, wday, mon, year, ctl2; 84 uchar buf[16]; 85 86 if (i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 16)) 87 printf("Error reading from RTC\n"); 88 89 sec = rtc_read(RTC_SEC_REG_ADDR); 90 min = rtc_read(RTC_MIN_REG_ADDR); 91 hour = rtc_read(RTC_HR_REG_ADDR); 92 wday = rtc_read(RTC_DAY_REG_ADDR); 93 mday = rtc_read(RTC_DATE_REG_ADDR); 94 mon = rtc_read(RTC_MON_REG_ADDR); 95 year = rtc_read(RTC_YR_REG_ADDR); 96 97 DEBUGR ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x " 98 "hr: %02x min: %02x sec: %02x\n", 99 year, mon, mday, wday, hour, min, sec); 100 101 /* dump status */ 102 ctl2 = rtc_read(RTC_CTL2_REG_ADDR); 103 if (ctl2 & RTC_CTL2_BIT_PON) { 104 printf("RTC: power-on detected\n"); 105 rel = -1; 106 } 107 108 if (ctl2 & RTC_CTL2_BIT_VDET) { 109 printf("RTC: voltage drop detected\n"); 110 rel = -1; 111 } 112 113 if (!(ctl2 & RTC_CTL2_BIT_XST)) { 114 printf("RTC: oscillator stop detected\n"); 115 rel = -1; 116 } 117 118 tmp->tm_sec = bcd2bin (sec & 0x7F); 119 tmp->tm_min = bcd2bin (min & 0x7F); 120 if (rtc_read(RTC_CTL1_REG_ADDR) & RTC_CTL1_BIT_2412) 121 tmp->tm_hour = bcd2bin (hour & 0x3F); 122 else 123 tmp->tm_hour = bcd2bin (hour & 0x1F) % 12 + 124 ((hour & 0x20) ? 12 : 0); 125 tmp->tm_mday = bcd2bin (mday & 0x3F); 126 tmp->tm_mon = bcd2bin (mon & 0x1F); 127 tmp->tm_year = bcd2bin (year) + ( bcd2bin (year) >= 70 ? 1900 : 2000); 128 tmp->tm_wday = bcd2bin (wday & 0x07); 129 tmp->tm_yday = 0; 130 tmp->tm_isdst= 0; 131 132 DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 133 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 134 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 135 136 return rel; 137 } 138 139 /* 140 * Set the RTC 141 */ 142 int rtc_set (struct rtc_time *tmp) 143 { 144 DEBUGR ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 145 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 146 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 147 148 if (tmp->tm_year < 1970 || tmp->tm_year > 2069) 149 printf("WARNING: year should be between 1970 and 2069!\n"); 150 151 rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100)); 152 rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon)); 153 rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday)); 154 rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday)); 155 rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour)); 156 rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min)); 157 rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec)); 158 159 rtc_write (RTC_CTL1_REG_ADDR, RTC_CTL1_BIT_2412); 160 161 return 0; 162 } 163 164 /* 165 * Reset the RTC 166 */ 167 void rtc_reset (void) 168 { 169 uchar buf[16]; 170 uchar ctl2; 171 172 if (i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 16)) 173 printf("Error reading from RTC\n"); 174 175 ctl2 = rtc_read(RTC_CTL2_REG_ADDR); 176 ctl2 &= ~(RTC_CTL2_BIT_PON | RTC_CTL2_BIT_VDET); 177 ctl2 |= RTC_CTL2_BIT_XST | RTC_CTL2_BIT_VDSL; 178 rtc_write (RTC_CTL2_REG_ADDR, ctl2); 179 } 180 181 /* 182 * Helper functions 183 */ 184 static void rtc_write (uchar reg, uchar val) 185 { 186 uchar buf[2]; 187 buf[0] = reg << 4; 188 buf[1] = val; 189 if (i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 2) != 0) 190 printf("Error writing to RTC\n"); 191 192 } 193 194 #endif /* CONFIG_RTC_RX8025 && CONFIG_CMD_DATE */ 195
