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 * This program is distributed in the hope that it will be useful, 22 * but WITHOUT ANY WARRANTY; without even the implied warranty of 23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 24 * GNU General Public License for more details. 25 * 26 * You should have received a copy of the GNU General Public License 27 * along with this program; if not, write to the Free Software 28 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 29 * MA 02111-1307 USA 30 */ 31 32 #include <common.h> 33 #include <command.h> 34 #include <rtc.h> 35 #include <i2c.h> 36 37 #if defined(CONFIG_CMD_DATE) 38 /* 39 * Reads are always done starting with register 15, which requires some 40 * jumping-through-hoops to access the data correctly. 41 * 42 * Writes are always done starting with register 0. 43 */ 44 45 #define DEBUG 0 46 47 #if DEBUG 48 static unsigned int rtc_debug = DEBUG; 49 #else 50 #define rtc_debug 0 /* gcc will remove all the debug code for us */ 51 #endif 52 53 #ifndef CONFIG_SYS_I2C_RTC_ADDR 54 #define CONFIG_SYS_I2C_RTC_ADDR 0x32 55 #endif 56 57 #define RS5C372_RAM_SIZE 0x10 58 #define RATE_32000HZ 0x80 /* Rate Select 32.000KHz */ 59 #define RATE_32768HZ 0x00 /* Rate Select 32.768KHz */ 60 61 #define STATUS_XPT 0x10 /* data invalid because voltage was 0 */ 62 63 #define USE_24HOUR_MODE 0x20 64 #define TWELVE_HOUR_MODE(n) ((((n) >> 5) & 1) == 0) 65 #define HOURS_AP(n) (((n) >> 5) & 1) 66 #define HOURS_12(n) bcd2bin((n) & 0x1F) 67 #define HOURS_24(n) bcd2bin((n) & 0x3F) 68 69 70 static uchar bin2bcd (unsigned int n); 71 static unsigned bcd2bin (uchar c); 72 73 static int setup_done = 0; 74 75 static int 76 rs5c372_readram(unsigned char *buf, int len) 77 { 78 int ret; 79 80 ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, len); 81 if (ret != 0) { 82 printf("%s: failed to read\n", __FUNCTION__); 83 return ret; 84 } 85 86 if (buf[0] & STATUS_XPT) 87 printf("### Warning: RTC lost power\n"); 88 89 return ret; 90 } 91 92 static void 93 rs5c372_enable(void) 94 { 95 unsigned char buf[RS5C372_RAM_SIZE + 1]; 96 int ret; 97 98 /* note that this returns reg. 15 in buf[1] */ 99 ret = rs5c372_readram(&buf[1], RS5C372_RAM_SIZE); 100 if (ret != 0) { 101 printf("%s: failed\n", __FUNCTION__); 102 return; 103 } 104 105 buf[0] = 0; 106 /* we want to start writing at register 0 so we have to copy the */ 107 /* register contents up one slot */ 108 for (ret = 2; ret < 9; ret++) 109 buf[ret - 1] = buf[ret]; 110 /* registers 0 to 6 (time values) are not touched */ 111 buf[8] = RATE_32768HZ; /* reg. 7 */ 112 buf[9] = 0; /* reg. 8 */ 113 buf[10] = 0; /* reg. 9 */ 114 buf[11] = 0; /* reg. 10 */ 115 buf[12] = 0; /* reg. 11 */ 116 buf[13] = 0; /* reg. 12 */ 117 buf[14] = 0; /* reg. 13 */ 118 buf[15] = 0; /* reg. 14 */ 119 buf[16] = USE_24HOUR_MODE; /* reg. 15 */ 120 ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, RS5C372_RAM_SIZE+1); 121 if (ret != 0) { 122 printf("%s: failed\n", __FUNCTION__); 123 return; 124 } 125 setup_done = 1; 126 127 return; 128 } 129 130 static void 131 rs5c372_convert_to_time(struct rtc_time *dt, unsigned char *buf) 132 { 133 /* buf[0] is register 15 */ 134 dt->tm_sec = bcd2bin(buf[1]); 135 dt->tm_min = bcd2bin(buf[2]); 136 137 if (TWELVE_HOUR_MODE(buf[0])) { 138 dt->tm_hour = HOURS_12(buf[3]); 139 if (HOURS_AP(buf[3])) /* PM */ 140 dt->tm_hour += 12; 141 } else /* 24-hour-mode */ 142 dt->tm_hour = HOURS_24(buf[3]); 143 144 dt->tm_mday = bcd2bin(buf[5]); 145 dt->tm_mon = bcd2bin(buf[6]); 146 dt->tm_year = bcd2bin(buf[7]); 147 if (dt->tm_year >= 70) 148 dt->tm_year += 1900; 149 else 150 dt->tm_year += 2000; 151 /* 0 is Sunday */ 152 dt->tm_wday = bcd2bin(buf[4] & 0x07); 153 dt->tm_yday = 0; 154 dt->tm_isdst= 0; 155 156 if(rtc_debug > 2) { 157 printf("rs5c372_convert_to_time: year = %d\n", dt->tm_year); 158 printf("rs5c372_convert_to_time: mon = %d\n", dt->tm_mon); 159 printf("rs5c372_convert_to_time: mday = %d\n", dt->tm_mday); 160 printf("rs5c372_convert_to_time: hour = %d\n", dt->tm_hour); 161 printf("rs5c372_convert_to_time: min = %d\n", dt->tm_min); 162 printf("rs5c372_convert_to_time: sec = %d\n", dt->tm_sec); 163 } 164 } 165 166 /* 167 * Get the current time from the RTC 168 */ 169 int 170 rtc_get (struct rtc_time *tmp) 171 { 172 unsigned char buf[RS5C372_RAM_SIZE]; 173 int ret; 174 175 if (!setup_done) 176 rs5c372_enable(); 177 178 if (!setup_done) 179 return -1; 180 181 memset(buf, 0, sizeof(buf)); 182 183 /* note that this returns reg. 15 in buf[0] */ 184 ret = rs5c372_readram(buf, RS5C372_RAM_SIZE); 185 if (ret != 0) { 186 printf("%s: failed\n", __FUNCTION__); 187 return -1; 188 } 189 190 rs5c372_convert_to_time(tmp, buf); 191 192 return 0; 193 } 194 195 /* 196 * Set the RTC 197 */ 198 int rtc_set (struct rtc_time *tmp) 199 { 200 unsigned char buf[8], reg15; 201 int ret; 202 203 if (!setup_done) 204 rs5c372_enable(); 205 206 if (!setup_done) 207 return -1; 208 209 if(rtc_debug > 2) { 210 printf("rtc_set: tm_year = %d\n", tmp->tm_year); 211 printf("rtc_set: tm_mon = %d\n", tmp->tm_mon); 212 printf("rtc_set: tm_mday = %d\n", tmp->tm_mday); 213 printf("rtc_set: tm_hour = %d\n", tmp->tm_hour); 214 printf("rtc_set: tm_min = %d\n", tmp->tm_min); 215 printf("rtc_set: tm_sec = %d\n", tmp->tm_sec); 216 } 217 218 memset(buf, 0, sizeof(buf)); 219 220 /* only read register 15 */ 221 ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 1); 222 223 if (ret == 0) { 224 /* need to save register 15 */ 225 reg15 = buf[0]; 226 buf[0] = 0; /* register address on RS5C372 */ 227 buf[1] = bin2bcd(tmp->tm_sec); 228 buf[2] = bin2bcd(tmp->tm_min); 229 /* need to handle 12 hour mode */ 230 if (TWELVE_HOUR_MODE(reg15)) { 231 if (tmp->tm_hour >= 12) { /* PM */ 232 /* 12 PM is a special case */ 233 if (tmp->tm_hour == 12) 234 buf[3] = bin2bcd(tmp->tm_hour); 235 else 236 buf[3] = bin2bcd(tmp->tm_hour - 12); 237 buf[3] |= 0x20; 238 } 239 } else { 240 buf[3] = bin2bcd(tmp->tm_hour); 241 } 242 243 buf[4] = bin2bcd(tmp->tm_wday); 244 buf[5] = bin2bcd(tmp->tm_mday); 245 buf[6] = bin2bcd(tmp->tm_mon); 246 if (tmp->tm_year < 1970 || tmp->tm_year > 2069) 247 printf("WARNING: year should be between 1970 and 2069!\n"); 248 buf[7] = bin2bcd(tmp->tm_year % 100); 249 250 ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 8); 251 if (ret != 0) { 252 printf("rs5c372_set_datetime(), i2c_master_send() returned %d\n",ret); 253 return -1; 254 } 255 } else { 256 return -1; 257 } 258 259 return 0; 260 } 261 262 /* 263 * Reset the RTC. We set the date back to 1970-01-01. 264 */ 265 void 266 rtc_reset (void) 267 { 268 struct rtc_time tmp; 269 270 if (!setup_done) 271 rs5c372_enable(); 272 273 if (!setup_done) 274 return; 275 276 tmp.tm_year = 1970; 277 tmp.tm_mon = 1; 278 /* Jan. 1, 1970 was a Thursday */ 279 tmp.tm_wday= 4; 280 tmp.tm_mday= 1; 281 tmp.tm_hour = 0; 282 tmp.tm_min = 0; 283 tmp.tm_sec = 0; 284 285 rtc_set(&tmp); 286 287 printf ("RTC: %4d-%02d-%02d %2d:%02d:%02d UTC\n", 288 tmp.tm_year, tmp.tm_mon, tmp.tm_mday, 289 tmp.tm_hour, tmp.tm_min, tmp.tm_sec); 290 291 return; 292 } 293 294 static unsigned int 295 bcd2bin (unsigned char n) 296 { 297 return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F)); 298 } 299 300 static unsigned char 301 bin2bcd (unsigned int n) 302 { 303 return (((n / 10) << 4) | (n % 10)); 304 } 305 #endif 306