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wdenkb6508512004-10-10 18:03:33 +00001/*
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_RTC_RS5C372A) && (CONFIG_COMMANDS & CFG_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
48static 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 CFG_I2C_RTC_ADDR
54#define CFG_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
70static uchar bin2bcd (unsigned int n);
71static unsigned bcd2bin (uchar c);
72
73static int setup_done = 0;
74
75static int
Wolfgang Denkd52fb7e2006-03-11 22:53:33 +010076rs5c372_readram(unsigned char *buf, int len)
wdenkb6508512004-10-10 18:03:33 +000077{
78 int ret;
79
80 ret = i2c_read(CFG_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
92static void
93rs5c372_enable(void)
94{
95 unsigned char buf[RS5C372_RAM_SIZE + 1];
96 int ret;
97
wdenkb6508512004-10-10 18:03:33 +000098 /* 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(CFG_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
130static void
Wolfgang Denkd52fb7e2006-03-11 22:53:33 +0100131rs5c372_convert_to_time(struct rtc_time *dt, unsigned char *buf)
wdenkb6508512004-10-10 18:03:33 +0000132{
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 */
169void
170rtc_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;
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;
188 }
189
190 rs5c372_convert_to_time(tmp, buf);
191
192 return;
193}
194
195/*
196 * Set the RTC
197 */
198void
199rtc_set (struct rtc_time *tmp)
200{
201 unsigned char buf[8], reg15;
202 int ret;
203
204 if (!setup_done)
205 rs5c372_enable();
206
207 if (!setup_done)
208 return;
209
210 if(rtc_debug > 2) {
211 printf("rtc_set: tm_year = %d\n", tmp->tm_year);
212 printf("rtc_set: tm_mon = %d\n", tmp->tm_mon);
213 printf("rtc_set: tm_mday = %d\n", tmp->tm_mday);
214 printf("rtc_set: tm_hour = %d\n", tmp->tm_hour);
215 printf("rtc_set: tm_min = %d\n", tmp->tm_min);
216 printf("rtc_set: tm_sec = %d\n", tmp->tm_sec);
217 }
218
219 memset(buf, 0, sizeof(buf));
220
221 /* only read register 15 */
222 ret = i2c_read(CFG_I2C_RTC_ADDR, 0, 0, buf, 1);
223
224 if (ret == 0) {
225 /* need to save register 15 */
226 reg15 = buf[0];
227 buf[0] = 0; /* register address on RS5C372 */
228 buf[1] = bin2bcd(tmp->tm_sec);
229 buf[2] = bin2bcd(tmp->tm_min);
230 /* need to handle 12 hour mode */
231 if (TWELVE_HOUR_MODE(reg15)) {
232 if (tmp->tm_hour >= 12) { /* PM */
233 /* 12 PM is a special case */
234 if (tmp->tm_hour == 12)
235 buf[3] = bin2bcd(tmp->tm_hour);
236 else
237 buf[3] = bin2bcd(tmp->tm_hour - 12);
238 buf[3] |= 0x20;
239 }
240 } else {
241 buf[3] = bin2bcd(tmp->tm_hour);
242 }
243
244 buf[4] = bin2bcd(tmp->tm_wday);
245 buf[5] = bin2bcd(tmp->tm_mday);
246 buf[6] = bin2bcd(tmp->tm_mon);
247 if (tmp->tm_year < 1970 || tmp->tm_year > 2069)
248 printf("WARNING: year should be between 1970 and 2069!\n");
249 buf[7] = bin2bcd(tmp->tm_year % 100);
250
251 ret = i2c_write(CFG_I2C_RTC_ADDR, 0, 0, buf, 8);
252 if (ret != 0)
253 printf("rs5c372_set_datetime(), i2c_master_send() returned %d\n",ret);
254 }
255
256 return;
257}
258
259/*
260 * Reset the RTC. We set the date back to 1970-01-01.
261 */
262void
263rtc_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
291static unsigned int
292bcd2bin (unsigned char n)
293{
294 return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F));
295}
296
297static unsigned char
298bin2bcd (unsigned int n)
299{
300 return (((n / 10) << 4) | (n % 10));
301}
302#endif /* defined(CONFIG_RTC_RS5C372A) && (CONFIG_COMMANDS & CFG_CMD_DATE) */