1 /* 2 * rs5c372.c 3 * 4 * Device driver for Ricoh's Real Time Controller RS5C372A. 5 * 6 * Copyright (C) 2004 Gary Jennejohn garyj@denx.de 7 * 8 * Based in part in ds1307.c - 9 * (C) Copyright 2001, 2002, 2003 10 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 11 * Keith Outwater, keith_outwater@mvis.com` 12 * Steven Scholz, steven.scholz@imc-berlin.de 13 * 14 * See file CREDITS for list of people who contributed to this 15 * project. 16 * 17 * This program is free software; you can redistribute it and/or modify 18 * it under the terms of the GNU General Public License version 2 as 19 * published by the Free Software Foundation. 20 */ 21 22 #include <common.h> 23 #include <command.h> 24 #include <rtc.h> 25 #include <i2c.h> 26 27 #if defined(CONFIG_CMD_DATE) 28 /* 29 * Reads are always done starting with register 15, which requires some 30 * jumping-through-hoops to access the data correctly. 31 * 32 * Writes are always done starting with register 0. 33 */ 34 35 #define DEBUG 0 36 37 #if DEBUG 38 static unsigned int rtc_debug = DEBUG; 39 #else 40 #define rtc_debug 0 /* gcc will remove all the debug code for us */ 41 #endif 42 43 #ifndef CONFIG_SYS_I2C_RTC_ADDR 44 #define CONFIG_SYS_I2C_RTC_ADDR 0x32 45 #endif 46 47 #define RS5C372_RAM_SIZE 0x10 48 #define RATE_32000HZ 0x80 /* Rate Select 32.000KHz */ 49 #define RATE_32768HZ 0x00 /* Rate Select 32.768KHz */ 50 51 #define STATUS_XPT 0x10 /* data invalid because voltage was 0 */ 52 53 #define USE_24HOUR_MODE 0x20 54 #define TWELVE_HOUR_MODE(n) ((((n) >> 5) & 1) == 0) 55 #define HOURS_AP(n) (((n) >> 5) & 1) 56 #define HOURS_12(n) bcd2bin((n) & 0x1F) 57 #define HOURS_24(n) bcd2bin((n) & 0x3F) 58 59 60 static int setup_done = 0; 61 62 static int 63 rs5c372_readram(unsigned char *buf, int len) 64 { 65 int ret; 66 67 ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, len); 68 if (ret != 0) { 69 printf("%s: failed to read\n", __FUNCTION__); 70 return ret; 71 } 72 73 if (buf[0] & STATUS_XPT) 74 printf("### Warning: RTC lost power\n"); 75 76 return ret; 77 } 78 79 static void 80 rs5c372_enable(void) 81 { 82 unsigned char buf[RS5C372_RAM_SIZE + 1]; 83 int ret; 84 85 /* note that this returns reg. 15 in buf[1] */ 86 ret = rs5c372_readram(&buf[1], RS5C372_RAM_SIZE); 87 if (ret != 0) { 88 printf("%s: failed\n", __FUNCTION__); 89 return; 90 } 91 92 buf[0] = 0; 93 /* we want to start writing at register 0 so we have to copy the */ 94 /* register contents up one slot */ 95 for (ret = 2; ret < 9; ret++) 96 buf[ret - 1] = buf[ret]; 97 /* registers 0 to 6 (time values) are not touched */ 98 buf[8] = RATE_32768HZ; /* reg. 7 */ 99 buf[9] = 0; /* reg. 8 */ 100 buf[10] = 0; /* reg. 9 */ 101 buf[11] = 0; /* reg. 10 */ 102 buf[12] = 0; /* reg. 11 */ 103 buf[13] = 0; /* reg. 12 */ 104 buf[14] = 0; /* reg. 13 */ 105 buf[15] = 0; /* reg. 14 */ 106 buf[16] = USE_24HOUR_MODE; /* reg. 15 */ 107 ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, RS5C372_RAM_SIZE+1); 108 if (ret != 0) { 109 printf("%s: failed\n", __FUNCTION__); 110 return; 111 } 112 setup_done = 1; 113 114 return; 115 } 116 117 static void 118 rs5c372_convert_to_time(struct rtc_time *dt, unsigned char *buf) 119 { 120 /* buf[0] is register 15 */ 121 dt->tm_sec = bcd2bin(buf[1]); 122 dt->tm_min = bcd2bin(buf[2]); 123 124 if (TWELVE_HOUR_MODE(buf[0])) { 125 dt->tm_hour = HOURS_12(buf[3]); 126 if (HOURS_AP(buf[3])) /* PM */ 127 dt->tm_hour += 12; 128 } else /* 24-hour-mode */ 129 dt->tm_hour = HOURS_24(buf[3]); 130 131 dt->tm_mday = bcd2bin(buf[5]); 132 dt->tm_mon = bcd2bin(buf[6]); 133 dt->tm_year = bcd2bin(buf[7]); 134 if (dt->tm_year >= 70) 135 dt->tm_year += 1900; 136 else 137 dt->tm_year += 2000; 138 /* 0 is Sunday */ 139 dt->tm_wday = bcd2bin(buf[4] & 0x07); 140 dt->tm_yday = 0; 141 dt->tm_isdst= 0; 142 143 if(rtc_debug > 2) { 144 printf("rs5c372_convert_to_time: year = %d\n", dt->tm_year); 145 printf("rs5c372_convert_to_time: mon = %d\n", dt->tm_mon); 146 printf("rs5c372_convert_to_time: mday = %d\n", dt->tm_mday); 147 printf("rs5c372_convert_to_time: hour = %d\n", dt->tm_hour); 148 printf("rs5c372_convert_to_time: min = %d\n", dt->tm_min); 149 printf("rs5c372_convert_to_time: sec = %d\n", dt->tm_sec); 150 } 151 } 152 153 /* 154 * Get the current time from the RTC 155 */ 156 int 157 rtc_get (struct rtc_time *tmp) 158 { 159 unsigned char buf[RS5C372_RAM_SIZE]; 160 int ret; 161 162 if (!setup_done) 163 rs5c372_enable(); 164 165 if (!setup_done) 166 return -1; 167 168 memset(buf, 0, sizeof(buf)); 169 170 /* note that this returns reg. 15 in buf[0] */ 171 ret = rs5c372_readram(buf, RS5C372_RAM_SIZE); 172 if (ret != 0) { 173 printf("%s: failed\n", __FUNCTION__); 174 return -1; 175 } 176 177 rs5c372_convert_to_time(tmp, buf); 178 179 return 0; 180 } 181 182 /* 183 * Set the RTC 184 */ 185 int rtc_set (struct rtc_time *tmp) 186 { 187 unsigned char buf[8], reg15; 188 int ret; 189 190 if (!setup_done) 191 rs5c372_enable(); 192 193 if (!setup_done) 194 return -1; 195 196 if(rtc_debug > 2) { 197 printf("rtc_set: tm_year = %d\n", tmp->tm_year); 198 printf("rtc_set: tm_mon = %d\n", tmp->tm_mon); 199 printf("rtc_set: tm_mday = %d\n", tmp->tm_mday); 200 printf("rtc_set: tm_hour = %d\n", tmp->tm_hour); 201 printf("rtc_set: tm_min = %d\n", tmp->tm_min); 202 printf("rtc_set: tm_sec = %d\n", tmp->tm_sec); 203 } 204 205 memset(buf, 0, sizeof(buf)); 206 207 /* only read register 15 */ 208 ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 1); 209 210 if (ret == 0) { 211 /* need to save register 15 */ 212 reg15 = buf[0]; 213 buf[0] = 0; /* register address on RS5C372 */ 214 buf[1] = bin2bcd(tmp->tm_sec); 215 buf[2] = bin2bcd(tmp->tm_min); 216 /* need to handle 12 hour mode */ 217 if (TWELVE_HOUR_MODE(reg15)) { 218 if (tmp->tm_hour >= 12) { /* PM */ 219 /* 12 PM is a special case */ 220 if (tmp->tm_hour == 12) 221 buf[3] = bin2bcd(tmp->tm_hour); 222 else 223 buf[3] = bin2bcd(tmp->tm_hour - 12); 224 buf[3] |= 0x20; 225 } 226 } else { 227 buf[3] = bin2bcd(tmp->tm_hour); 228 } 229 230 buf[4] = bin2bcd(tmp->tm_wday); 231 buf[5] = bin2bcd(tmp->tm_mday); 232 buf[6] = bin2bcd(tmp->tm_mon); 233 if (tmp->tm_year < 1970 || tmp->tm_year > 2069) 234 printf("WARNING: year should be between 1970 and 2069!\n"); 235 buf[7] = bin2bcd(tmp->tm_year % 100); 236 237 ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 8); 238 if (ret != 0) { 239 printf("rs5c372_set_datetime(), i2c_master_send() returned %d\n",ret); 240 return -1; 241 } 242 } else { 243 return -1; 244 } 245 246 return 0; 247 } 248 249 /* 250 * Reset the RTC. We set the date back to 1970-01-01. 251 */ 252 void 253 rtc_reset (void) 254 { 255 struct rtc_time tmp; 256 257 if (!setup_done) 258 rs5c372_enable(); 259 260 if (!setup_done) 261 return; 262 263 tmp.tm_year = 1970; 264 tmp.tm_mon = 1; 265 /* Jan. 1, 1970 was a Thursday */ 266 tmp.tm_wday= 4; 267 tmp.tm_mday= 1; 268 tmp.tm_hour = 0; 269 tmp.tm_min = 0; 270 tmp.tm_sec = 0; 271 272 rtc_set(&tmp); 273 274 printf ("RTC: %4d-%02d-%02d %2d:%02d:%02d UTC\n", 275 tmp.tm_year, tmp.tm_mon, tmp.tm_mday, 276 tmp.tm_hour, tmp.tm_min, tmp.tm_sec); 277 278 return; 279 } 280 281 #endif 282