1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
|
// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2007
* Matthias Fuchs, esd gmbh, matthias.fuchs@esd-electronics.com.
*/
/*
* Epson RX8025 RTC driver.
*/
#include <command.h>
#include <dm.h>
#include <i2c.h>
#include <rtc.h>
/*---------------------------------------------------------------------*/
#undef DEBUG_RTC
#ifdef DEBUG_RTC
#define DEBUGR(fmt,args...) printf(fmt ,##args)
#else
#define DEBUGR(fmt,args...)
#endif
/*---------------------------------------------------------------------*/
enum rx_model {
model_rx_8025,
model_rx_8035,
};
/*
* RTC register addresses
*/
#define RTC_SEC_REG_ADDR 0x00
#define RTC_MIN_REG_ADDR 0x01
#define RTC_HR_REG_ADDR 0x02
#define RTC_DAY_REG_ADDR 0x03
#define RTC_DATE_REG_ADDR 0x04
#define RTC_MON_REG_ADDR 0x05
#define RTC_YR_REG_ADDR 0x06
#define RTC_OFFSET_REG_ADDR 0x07
#define RTC_CTL1_REG_ADDR 0x0e
#define RTC_CTL2_REG_ADDR 0x0f
/*
* Control register 1 bits
*/
#define RTC_CTL1_BIT_2412 0x20
/*
* Control register 2 bits
*/
#define RTC_CTL2_BIT_PON 0x10
#define RTC_CTL2_BIT_VDET 0x40
#define RTC_CTL2_BIT_XST 0x20
#define RTC_CTL2_BIT_VDSL 0x80
/*
* Note: the RX8025 I2C RTC requires register
* reads and write to consist of a single bus
* cycle. It is not allowed to write the register
* address in a first cycle that is terminated by
* a STOP condition. The chips needs a 'restart'
* sequence (start sequence without a prior stop).
*/
#define rtc_read(reg) buf[(reg) & 0xf]
static int rtc_write(struct udevice *dev, uchar reg, uchar val);
static int rx8025_is_osc_stopped(enum rx_model model, int ctrl2)
{
int xstp = ctrl2 & RTC_CTL2_BIT_XST;
/* XSTP bit has different polarity on RX-8025 vs RX-8035.
* RX-8025: 0 == oscillator stopped
* RX-8035: 1 == oscillator stopped
*/
if (model == model_rx_8025)
xstp = !xstp;
return xstp;
}
/*
* Get the current time from the RTC
*/
static int rx8025_rtc_get(struct udevice *dev, struct rtc_time *tmp)
{
int rel = 0;
uchar sec, min, hour, mday, wday, mon, year, ctl2;
uchar buf[16];
if (dm_i2c_read(dev, 0, buf, sizeof(buf))) {
printf("Error reading from RTC\n");
return -EIO;
}
sec = rtc_read(RTC_SEC_REG_ADDR);
min = rtc_read(RTC_MIN_REG_ADDR);
hour = rtc_read(RTC_HR_REG_ADDR);
wday = rtc_read(RTC_DAY_REG_ADDR);
mday = rtc_read(RTC_DATE_REG_ADDR);
mon = rtc_read(RTC_MON_REG_ADDR);
year = rtc_read(RTC_YR_REG_ADDR);
DEBUGR("Get RTC year: %02x mon: %02x mday: %02x wday: %02x "
"hr: %02x min: %02x sec: %02x\n",
year, mon, mday, wday, hour, min, sec);
/* dump status */
ctl2 = rtc_read(RTC_CTL2_REG_ADDR);
if (ctl2 & RTC_CTL2_BIT_PON) {
printf("RTC: power-on detected\n");
rel = -1;
}
if (ctl2 & RTC_CTL2_BIT_VDET) {
printf("RTC: voltage drop detected\n");
rel = -1;
}
if (rx8025_is_osc_stopped(dev->driver_data, ctl2)) {
printf("RTC: oscillator stop detected\n");
rel = -1;
}
tmp->tm_sec = bcd2bin(sec & 0x7F);
tmp->tm_min = bcd2bin(min & 0x7F);
if (rtc_read(RTC_CTL1_REG_ADDR) & RTC_CTL1_BIT_2412)
tmp->tm_hour = bcd2bin(hour & 0x3F);
else
tmp->tm_hour = bcd2bin(hour & 0x1F) % 12 +
((hour & 0x20) ? 12 : 0);
tmp->tm_mday = bcd2bin (mday & 0x3F);
tmp->tm_mon = bcd2bin (mon & 0x1F);
tmp->tm_year = bcd2bin (year) + ( bcd2bin (year) >= 70 ? 1900 : 2000);
tmp->tm_wday = bcd2bin (wday & 0x07);
tmp->tm_yday = 0;
tmp->tm_isdst= 0;
DEBUGR("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
return rel;
}
/*
* Set the RTC
*/
static int rx8025_rtc_set(struct udevice *dev, const struct rtc_time *tmp)
{
/* To work around the read/write cycle issue mentioned
* at the top of this file, write all the time registers
* in one I2C transaction
*/
u8 write_op[8];
/* 2412 flag must be set before doing a RTC write,
* otherwise the seconds and minute register
* will be cleared when the flag is set
*/
if (rtc_write(dev, RTC_CTL1_REG_ADDR, RTC_CTL1_BIT_2412))
return -EIO;
DEBUGR("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
if (tmp->tm_year < 1970 || tmp->tm_year > 2069)
printf("WARNING: year should be between 1970 and 2069!\n");
write_op[RTC_SEC_REG_ADDR] = bin2bcd(tmp->tm_sec);
write_op[RTC_MIN_REG_ADDR] = bin2bcd(tmp->tm_min);
write_op[RTC_HR_REG_ADDR] = bin2bcd(tmp->tm_hour);
write_op[RTC_DAY_REG_ADDR] = bin2bcd(tmp->tm_wday);
write_op[RTC_DATE_REG_ADDR] = bin2bcd(tmp->tm_mday);
write_op[RTC_MON_REG_ADDR] = bin2bcd(tmp->tm_mon);
write_op[RTC_YR_REG_ADDR] = bin2bcd(tmp->tm_year % 100);
write_op[RTC_OFFSET_REG_ADDR] = 0;
return dm_i2c_write(dev, 0, &write_op[0], 8);
}
/*
* Reset the RTC
*/
static int rx8025_rtc_reset(struct udevice *dev)
{
uchar buf[16];
uchar ctl2;
if (dm_i2c_read(dev, 0, buf, sizeof(buf))) {
printf("Error reading from RTC\n");
return -EIO;
}
ctl2 = rtc_read(RTC_CTL2_REG_ADDR);
ctl2 &= ~(RTC_CTL2_BIT_PON | RTC_CTL2_BIT_VDET);
if (dev->driver_data == model_rx_8035)
ctl2 &= ~(RTC_CTL2_BIT_XST);
else
ctl2 |= RTC_CTL2_BIT_XST;
return rtc_write(dev, RTC_CTL2_REG_ADDR, ctl2);
}
/*
* Helper functions
*/
static int rtc_write(struct udevice *dev, uchar reg, uchar val)
{
/* The RX8025/RX8035 uses the top 4 bits of the
* 'offset' byte as the start register address,
* and the bottom 4 bits as a 'transfer' mode setting
* (only applicable for reads)
*/
u8 offset = (reg << 4);
if (dm_i2c_reg_write(dev, offset, val)) {
printf("Error writing to RTC\n");
return -EIO;
}
return 0;
}
static int rx8025_probe(struct udevice *dev)
{
uchar buf[16];
int ret = 0;
if (i2c_get_chip_offset_len(dev) != 1)
ret = i2c_set_chip_offset_len(dev, 1);
if (ret)
return ret;
return dm_i2c_read(dev, 0, buf, sizeof(buf));
}
static const struct rtc_ops rx8025_rtc_ops = {
.get = rx8025_rtc_get,
.set = rx8025_rtc_set,
.reset = rx8025_rtc_reset,
};
static const struct udevice_id rx8025_rtc_ids[] = {
{ .compatible = "epson,rx8025", .data = model_rx_8025 },
{ .compatible = "epson,rx8035", .data = model_rx_8035 },
{ }
};
U_BOOT_DRIVER(rx8025_rtc) = {
.name = "rx8025_rtc",
.id = UCLASS_RTC,
.probe = rx8025_probe,
.of_match = rx8025_rtc_ids,
.ops = &rx8025_rtc_ops,
};
|
