1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2007
4 * Matthias Fuchs, esd gmbh, matthias.fuchs@esd-electronics.com.
5 */
6
7 /*
8 * Epson RX8025 RTC driver.
9 */
10
11 #include <common.h>
12 #include <command.h>
13 #include <dm.h>
14 #include <i2c.h>
15 #include <rtc.h>
16
17 /*---------------------------------------------------------------------*/
18 #undef DEBUG_RTC
19
20 #ifdef DEBUG_RTC
21 #define DEBUGR(fmt,args...) printf(fmt ,##args)
22 #else
23 #define DEBUGR(fmt,args...)
24 #endif
25 /*---------------------------------------------------------------------*/
26
27 #ifndef CONFIG_SYS_I2C_RTC_ADDR
28 # define CONFIG_SYS_I2C_RTC_ADDR 0x32
29 #endif
30
31 #ifdef CONFIG_DM_RTC
32 #define DEV_TYPE struct udevice
33 #else
34 /* Local udevice */
35 struct ludevice {
36 u8 chip;
37 };
38
39 #define DEV_TYPE struct ludevice
40
41 #endif
42
43 /*
44 * RTC register addresses
45 */
46 #define RTC_SEC_REG_ADDR 0x00
47 #define RTC_MIN_REG_ADDR 0x01
48 #define RTC_HR_REG_ADDR 0x02
49 #define RTC_DAY_REG_ADDR 0x03
50 #define RTC_DATE_REG_ADDR 0x04
51 #define RTC_MON_REG_ADDR 0x05
52 #define RTC_YR_REG_ADDR 0x06
53
54 #define RTC_CTL1_REG_ADDR 0x0e
55 #define RTC_CTL2_REG_ADDR 0x0f
56
57 /*
58 * Control register 1 bits
59 */
60 #define RTC_CTL1_BIT_2412 0x20
61
62 /*
63 * Control register 2 bits
64 */
65 #define RTC_CTL2_BIT_PON 0x10
66 #define RTC_CTL2_BIT_VDET 0x40
67 #define RTC_CTL2_BIT_XST 0x20
68 #define RTC_CTL2_BIT_VDSL 0x80
69
70 /*
71 * Note: the RX8025 I2C RTC requires register
72 * reads and write to consist of a single bus
73 * cycle. It is not allowed to write the register
74 * address in a first cycle that is terminated by
75 * a STOP condition. The chips needs a 'restart'
76 * sequence (start sequence without a prior stop).
77 * This driver has been written for a 4xx board.
78 * U-Boot's 4xx i2c driver is currently not capable
79 * to generate such cycles to some work arounds
80 * are used.
81 */
82
83 /* static uchar rtc_read (uchar reg); */
84 #ifdef CONFIG_DM_RTC
85 /*
86 * on mpc85xx based board with DM and offset len 1
87 * accessing rtc works fine. May we can drop this ?
88 */
89 #define rtc_read(reg) buf[(reg) & 0xf]
90 #else
91 #define rtc_read(reg) buf[((reg) + 1) & 0xf]
92 #endif
93
94 static int rtc_write(DEV_TYPE *dev, uchar reg, uchar val);
95
96 /*
97 * Get the current time from the RTC
98 */
rx8025_rtc_get(DEV_TYPE * dev,struct rtc_time * tmp)99 static int rx8025_rtc_get(DEV_TYPE *dev, struct rtc_time *tmp)
100 {
101 int rel = 0;
102 uchar sec, min, hour, mday, wday, mon, year, ctl2;
103 uchar buf[16];
104
105 #ifdef CONFIG_DM_RTC
106 if (dm_i2c_read(dev, 0, buf, sizeof(buf))) {
107 #else
108 if (i2c_read(dev->chip, 0, 0, buf, 16)) {
109 #endif
110 printf("Error reading from RTC\n");
111 return -EIO;
112 }
113
114 sec = rtc_read(RTC_SEC_REG_ADDR);
115 min = rtc_read(RTC_MIN_REG_ADDR);
116 hour = rtc_read(RTC_HR_REG_ADDR);
117 wday = rtc_read(RTC_DAY_REG_ADDR);
118 mday = rtc_read(RTC_DATE_REG_ADDR);
119 mon = rtc_read(RTC_MON_REG_ADDR);
120 year = rtc_read(RTC_YR_REG_ADDR);
121
122 DEBUGR("Get RTC year: %02x mon: %02x mday: %02x wday: %02x "
123 "hr: %02x min: %02x sec: %02x\n",
124 year, mon, mday, wday, hour, min, sec);
125
126 /* dump status */
127 ctl2 = rtc_read(RTC_CTL2_REG_ADDR);
128 if (ctl2 & RTC_CTL2_BIT_PON) {
129 printf("RTC: power-on detected\n");
130 rel = -1;
131 }
132
133 if (ctl2 & RTC_CTL2_BIT_VDET) {
134 printf("RTC: voltage drop detected\n");
135 rel = -1;
136 }
137
138 if (!(ctl2 & RTC_CTL2_BIT_XST)) {
139 printf("RTC: oscillator stop detected\n");
140 rel = -1;
141 }
142
143 tmp->tm_sec = bcd2bin(sec & 0x7F);
144 tmp->tm_min = bcd2bin(min & 0x7F);
145 if (rtc_read(RTC_CTL1_REG_ADDR) & RTC_CTL1_BIT_2412)
146 tmp->tm_hour = bcd2bin(hour & 0x3F);
147 else
148 tmp->tm_hour = bcd2bin(hour & 0x1F) % 12 +
149 ((hour & 0x20) ? 12 : 0);
150
151 tmp->tm_mday = bcd2bin (mday & 0x3F);
152 tmp->tm_mon = bcd2bin (mon & 0x1F);
153 tmp->tm_year = bcd2bin (year) + ( bcd2bin (year) >= 70 ? 1900 : 2000);
154 tmp->tm_wday = bcd2bin (wday & 0x07);
155 tmp->tm_yday = 0;
156 tmp->tm_isdst= 0;
157
158 DEBUGR("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
159 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
160 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
161
162 return rel;
163 }
164
165 /*
166 * Set the RTC
167 */
168 static int rx8025_rtc_set(DEV_TYPE *dev, const struct rtc_time *tmp)
169 {
170 DEBUGR("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
171 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
172 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
173
174 if (tmp->tm_year < 1970 || tmp->tm_year > 2069)
175 printf("WARNING: year should be between 1970 and 2069!\n");
176
177 if (rtc_write(dev, RTC_YR_REG_ADDR, bin2bcd(tmp->tm_year % 100)))
178 return -EIO;
179
180 if (rtc_write(dev, RTC_MON_REG_ADDR, bin2bcd(tmp->tm_mon)))
181 return -EIO;
182
183 if (rtc_write(dev, RTC_DAY_REG_ADDR, bin2bcd(tmp->tm_wday)))
184 return -EIO;
185
186 if (rtc_write(dev, RTC_DATE_REG_ADDR, bin2bcd(tmp->tm_mday)))
187 return -EIO;
188
189 if (rtc_write(dev, RTC_HR_REG_ADDR, bin2bcd(tmp->tm_hour)))
190 return -EIO;
191
192 if (rtc_write(dev, RTC_MIN_REG_ADDR, bin2bcd(tmp->tm_min)))
193 return -EIO;
194
195 if (rtc_write(dev, RTC_SEC_REG_ADDR, bin2bcd(tmp->tm_sec)))
196 return -EIO;
197
198 return rtc_write(dev, RTC_CTL1_REG_ADDR, RTC_CTL1_BIT_2412);
199 }
200
201 /*
202 * Reset the RTC
203 */
204 static int rx8025_rtc_reset(DEV_TYPE *dev)
205 {
206 uchar buf[16];
207 uchar ctl2;
208
209 #ifdef CONFIG_DM_RTC
210 if (dm_i2c_read(dev, 0, buf, sizeof(buf))) {
211 #else
212 if (i2c_read(dev->chip, 0, 0, buf, 16)) {
213 #endif
214 printf("Error reading from RTC\n");
215 return -EIO;
216 }
217
218 ctl2 = rtc_read(RTC_CTL2_REG_ADDR);
219 ctl2 &= ~(RTC_CTL2_BIT_PON | RTC_CTL2_BIT_VDET);
220 ctl2 |= RTC_CTL2_BIT_XST | RTC_CTL2_BIT_VDSL;
221
222 return rtc_write(dev, RTC_CTL2_REG_ADDR, ctl2);
223 }
224
225 /*
226 * Helper functions
227 */
228 static int rtc_write(DEV_TYPE *dev, uchar reg, uchar val)
229 {
230 uchar buf[2];
231 buf[0] = reg << 4;
232 buf[1] = val;
233
234 #ifdef CONFIG_DM_RTC
235 if (dm_i2c_write(dev, 0, buf, 2)) {
236 #else
237 if (i2c_write(dev->chip, 0, 0, buf, 2) != 0) {
238 #endif
239 printf("Error writing to RTC\n");
240 return -EIO;
241 }
242
243 return 0;
244 }
245
246 #ifdef CONFIG_DM_RTC
247 static int rx8025_probe(struct udevice *dev)
248 {
249 uchar buf[16];
250 int ret = 0;
251
252 if (i2c_get_chip_offset_len(dev) != 1)
253 ret = i2c_set_chip_offset_len(dev, 1);
254
255 if (ret)
256 return ret;
257
258 return dm_i2c_read(dev, 0, buf, sizeof(buf));
259 }
260
261 static const struct rtc_ops rx8025_rtc_ops = {
262 .get = rx8025_rtc_get,
263 .set = rx8025_rtc_set,
264 .reset = rx8025_rtc_reset,
265 };
266
267 static const struct udevice_id rx8025_rtc_ids[] = {
268 { .compatible = "epson,rx8025" },
269 { }
270 };
271
272 U_BOOT_DRIVER(rx8010sj_rtc) = {
273 .name = "rx8025_rtc",
274 .id = UCLASS_RTC,
275 .probe = rx8025_probe,
276 .of_match = rx8025_rtc_ids,
277 .ops = &rx8025_rtc_ops,
278 };
279 #else
280 int rtc_get(struct rtc_time *tm)
281 {
282 struct ludevice dev = {
283 .chip = CONFIG_SYS_I2C_RTC_ADDR,
284 };
285
286 return rx8025_rtc_get(&dev, tm);
287 }
288
289 int rtc_set(struct rtc_time *tm)
290 {
291 struct ludevice dev = {
292 .chip = CONFIG_SYS_I2C_RTC_ADDR,
293 };
294
295 return rx8025_rtc_set(&dev, tm);
296 }
297
298 void rtc_reset(void)
299 {
300 struct ludevice dev = {
301 .chip = CONFIG_SYS_I2C_RTC_ADDR,
302 };
303
304 rx8025_rtc_reset(&dev);
305 }
306 #endif
307