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 int setup_done = 0; 71 72 static int 73 rs5c372_readram(unsigned char *buf, int len) 74 { 75 int ret; 76 77 ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, len); 78 if (ret != 0) { 79 printf("%s: failed to read\n", __FUNCTION__); 80 return ret; 81 } 82 83 if (buf[0] & STATUS_XPT) 84 printf("### Warning: RTC lost power\n"); 85 86 return ret; 87 } 88 89 static void 90 rs5c372_enable(void) 91 { 92 unsigned char buf[RS5C372_RAM_SIZE + 1]; 93 int ret; 94 95 /* note that this returns reg. 15 in buf[1] */ 96 ret = rs5c372_readram(&buf[1], RS5C372_RAM_SIZE); 97 if (ret != 0) { 98 printf("%s: failed\n", __FUNCTION__); 99 return; 100 } 101 102 buf[0] = 0; 103 /* we want to start writing at register 0 so we have to copy the */ 104 /* register contents up one slot */ 105 for (ret = 2; ret < 9; ret++) 106 buf[ret - 1] = buf[ret]; 107 /* registers 0 to 6 (time values) are not touched */ 108 buf[8] = RATE_32768HZ; /* reg. 7 */ 109 buf[9] = 0; /* reg. 8 */ 110 buf[10] = 0; /* reg. 9 */ 111 buf[11] = 0; /* reg. 10 */ 112 buf[12] = 0; /* reg. 11 */ 113 buf[13] = 0; /* reg. 12 */ 114 buf[14] = 0; /* reg. 13 */ 115 buf[15] = 0; /* reg. 14 */ 116 buf[16] = USE_24HOUR_MODE; /* reg. 15 */ 117 ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, RS5C372_RAM_SIZE+1); 118 if (ret != 0) { 119 printf("%s: failed\n", __FUNCTION__); 120 return; 121 } 122 setup_done = 1; 123 124 return; 125 } 126 127 static void 128 rs5c372_convert_to_time(struct rtc_time *dt, unsigned char *buf) 129 { 130 /* buf[0] is register 15 */ 131 dt->tm_sec = bcd2bin(buf[1]); 132 dt->tm_min = bcd2bin(buf[2]); 133 134 if (TWELVE_HOUR_MODE(buf[0])) { 135 dt->tm_hour = HOURS_12(buf[3]); 136 if (HOURS_AP(buf[3])) /* PM */ 137 dt->tm_hour += 12; 138 } else /* 24-hour-mode */ 139 dt->tm_hour = HOURS_24(buf[3]); 140 141 dt->tm_mday = bcd2bin(buf[5]); 142 dt->tm_mon = bcd2bin(buf[6]); 143 dt->tm_year = bcd2bin(buf[7]); 144 if (dt->tm_year >= 70) 145 dt->tm_year += 1900; 146 else 147 dt->tm_year += 2000; 148 /* 0 is Sunday */ 149 dt->tm_wday = bcd2bin(buf[4] & 0x07); 150 dt->tm_yday = 0; 151 dt->tm_isdst= 0; 152 153 if(rtc_debug > 2) { 154 printf("rs5c372_convert_to_time: year = %d\n", dt->tm_year); 155 printf("rs5c372_convert_to_time: mon = %d\n", dt->tm_mon); 156 printf("rs5c372_convert_to_time: mday = %d\n", dt->tm_mday); 157 printf("rs5c372_convert_to_time: hour = %d\n", dt->tm_hour); 158 printf("rs5c372_convert_to_time: min = %d\n", dt->tm_min); 159 printf("rs5c372_convert_to_time: sec = %d\n", dt->tm_sec); 160 } 161 } 162 163 /* 164 * Get the current time from the RTC 165 */ 166 int 167 rtc_get (struct rtc_time *tmp) 168 { 169 unsigned char buf[RS5C372_RAM_SIZE]; 170 int ret; 171 172 if (!setup_done) 173 rs5c372_enable(); 174 175 if (!setup_done) 176 return -1; 177 178 memset(buf, 0, sizeof(buf)); 179 180 /* note that this returns reg. 15 in buf[0] */ 181 ret = rs5c372_readram(buf, RS5C372_RAM_SIZE); 182 if (ret != 0) { 183 printf("%s: failed\n", __FUNCTION__); 184 return -1; 185 } 186 187 rs5c372_convert_to_time(tmp, buf); 188 189 return 0; 190 } 191 192 /* 193 * Set the RTC 194 */ 195 int rtc_set (struct rtc_time *tmp) 196 { 197 unsigned char buf[8], reg15; 198 int ret; 199 200 if (!setup_done) 201 rs5c372_enable(); 202 203 if (!setup_done) 204 return -1; 205 206 if(rtc_debug > 2) { 207 printf("rtc_set: tm_year = %d\n", tmp->tm_year); 208 printf("rtc_set: tm_mon = %d\n", tmp->tm_mon); 209 printf("rtc_set: tm_mday = %d\n", tmp->tm_mday); 210 printf("rtc_set: tm_hour = %d\n", tmp->tm_hour); 211 printf("rtc_set: tm_min = %d\n", tmp->tm_min); 212 printf("rtc_set: tm_sec = %d\n", tmp->tm_sec); 213 } 214 215 memset(buf, 0, sizeof(buf)); 216 217 /* only read register 15 */ 218 ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 1); 219 220 if (ret == 0) { 221 /* need to save register 15 */ 222 reg15 = buf[0]; 223 buf[0] = 0; /* register address on RS5C372 */ 224 buf[1] = bin2bcd(tmp->tm_sec); 225 buf[2] = bin2bcd(tmp->tm_min); 226 /* need to handle 12 hour mode */ 227 if (TWELVE_HOUR_MODE(reg15)) { 228 if (tmp->tm_hour >= 12) { /* PM */ 229 /* 12 PM is a special case */ 230 if (tmp->tm_hour == 12) 231 buf[3] = bin2bcd(tmp->tm_hour); 232 else 233 buf[3] = bin2bcd(tmp->tm_hour - 12); 234 buf[3] |= 0x20; 235 } 236 } else { 237 buf[3] = bin2bcd(tmp->tm_hour); 238 } 239 240 buf[4] = bin2bcd(tmp->tm_wday); 241 buf[5] = bin2bcd(tmp->tm_mday); 242 buf[6] = bin2bcd(tmp->tm_mon); 243 if (tmp->tm_year < 1970 || tmp->tm_year > 2069) 244 printf("WARNING: year should be between 1970 and 2069!\n"); 245 buf[7] = bin2bcd(tmp->tm_year % 100); 246 247 ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 8); 248 if (ret != 0) { 249 printf("rs5c372_set_datetime(), i2c_master_send() returned %d\n",ret); 250 return -1; 251 } 252 } else { 253 return -1; 254 } 255 256 return 0; 257 } 258 259 /* 260 * Reset the RTC. We set the date back to 1970-01-01. 261 */ 262 void 263 rtc_reset (void) 264 { 265 struct rtc_time tmp; 266 267 if (!setup_done) 268 rs5c372_enable(); 269 270 if (!setup_done) 271 return; 272 273 tmp.tm_year = 1970; 274 tmp.tm_mon = 1; 275 /* Jan. 1, 1970 was a Thursday */ 276 tmp.tm_wday= 4; 277 tmp.tm_mday= 1; 278 tmp.tm_hour = 0; 279 tmp.tm_min = 0; 280 tmp.tm_sec = 0; 281 282 rtc_set(&tmp); 283 284 printf ("RTC: %4d-%02d-%02d %2d:%02d:%02d UTC\n", 285 tmp.tm_year, tmp.tm_mon, tmp.tm_mday, 286 tmp.tm_hour, tmp.tm_min, tmp.tm_sec); 287 288 return; 289 } 290 291 #endif 292