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 <rtc.h>
14 #include <i2c.h>
15
16 #if defined(CONFIG_CMD_DATE)
17
18 /*---------------------------------------------------------------------*/
19 #undef DEBUG_RTC
20
21 #ifdef DEBUG_RTC
22 #define DEBUGR(fmt,args...) printf(fmt ,##args)
23 #else
24 #define DEBUGR(fmt,args...)
25 #endif
26 /*---------------------------------------------------------------------*/
27
28 #ifndef CONFIG_SYS_I2C_RTC_ADDR
29 # define CONFIG_SYS_I2C_RTC_ADDR 0x32
30 #endif
31
32 /*
33 * RTC register addresses
34 */
35 #define RTC_SEC_REG_ADDR 0x00
36 #define RTC_MIN_REG_ADDR 0x01
37 #define RTC_HR_REG_ADDR 0x02
38 #define RTC_DAY_REG_ADDR 0x03
39 #define RTC_DATE_REG_ADDR 0x04
40 #define RTC_MON_REG_ADDR 0x05
41 #define RTC_YR_REG_ADDR 0x06
42
43 #define RTC_CTL1_REG_ADDR 0x0e
44 #define RTC_CTL2_REG_ADDR 0x0f
45
46 /*
47 * Control register 1 bits
48 */
49 #define RTC_CTL1_BIT_2412 0x20
50
51 /*
52 * Control register 2 bits
53 */
54 #define RTC_CTL2_BIT_PON 0x10
55 #define RTC_CTL2_BIT_VDET 0x40
56 #define RTC_CTL2_BIT_XST 0x20
57 #define RTC_CTL2_BIT_VDSL 0x80
58
59 /*
60 * Note: the RX8025 I2C RTC requires register
61 * reads and write to consist of a single bus
62 * cycle. It is not allowed to write the register
63 * address in a first cycle that is terminated by
64 * a STOP condition. The chips needs a 'restart'
65 * sequence (start sequence without a prior stop).
66 * This driver has been written for a 4xx board.
67 * U-Boot's 4xx i2c driver is currently not capable
68 * to generate such cycles to some work arounds
69 * are used.
70 */
71
72 /* static uchar rtc_read (uchar reg); */
73 #define rtc_read(reg) buf[((reg) + 1) & 0xf]
74
75 static void rtc_write (uchar reg, uchar val);
76
77 /*
78 * Get the current time from the RTC
79 */
rtc_get(struct rtc_time * tmp)80 int rtc_get (struct rtc_time *tmp)
81 {
82 int rel = 0;
83 uchar sec, min, hour, mday, wday, mon, year, ctl2;
84 uchar buf[16];
85
86 if (i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 16))
87 printf("Error reading from RTC\n");
88
89 sec = rtc_read(RTC_SEC_REG_ADDR);
90 min = rtc_read(RTC_MIN_REG_ADDR);
91 hour = rtc_read(RTC_HR_REG_ADDR);
92 wday = rtc_read(RTC_DAY_REG_ADDR);
93 mday = rtc_read(RTC_DATE_REG_ADDR);
94 mon = rtc_read(RTC_MON_REG_ADDR);
95 year = rtc_read(RTC_YR_REG_ADDR);
96
97 DEBUGR ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x "
98 "hr: %02x min: %02x sec: %02x\n",
99 year, mon, mday, wday, hour, min, sec);
100
101 /* dump status */
102 ctl2 = rtc_read(RTC_CTL2_REG_ADDR);
103 if (ctl2 & RTC_CTL2_BIT_PON) {
104 printf("RTC: power-on detected\n");
105 rel = -1;
106 }
107
108 if (ctl2 & RTC_CTL2_BIT_VDET) {
109 printf("RTC: voltage drop detected\n");
110 rel = -1;
111 }
112
113 if (!(ctl2 & RTC_CTL2_BIT_XST)) {
114 printf("RTC: oscillator stop detected\n");
115 rel = -1;
116 }
117
118 tmp->tm_sec = bcd2bin (sec & 0x7F);
119 tmp->tm_min = bcd2bin (min & 0x7F);
120 if (rtc_read(RTC_CTL1_REG_ADDR) & RTC_CTL1_BIT_2412)
121 tmp->tm_hour = bcd2bin (hour & 0x3F);
122 else
123 tmp->tm_hour = bcd2bin (hour & 0x1F) % 12 +
124 ((hour & 0x20) ? 12 : 0);
125 tmp->tm_mday = bcd2bin (mday & 0x3F);
126 tmp->tm_mon = bcd2bin (mon & 0x1F);
127 tmp->tm_year = bcd2bin (year) + ( bcd2bin (year) >= 70 ? 1900 : 2000);
128 tmp->tm_wday = bcd2bin (wday & 0x07);
129 tmp->tm_yday = 0;
130 tmp->tm_isdst= 0;
131
132 DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
133 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
134 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
135
136 return rel;
137 }
138
139 /*
140 * Set the RTC
141 */
rtc_set(struct rtc_time * tmp)142 int rtc_set (struct rtc_time *tmp)
143 {
144 DEBUGR ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
145 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
146 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
147
148 if (tmp->tm_year < 1970 || tmp->tm_year > 2069)
149 printf("WARNING: year should be between 1970 and 2069!\n");
150
151 rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100));
152 rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon));
153 rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday));
154 rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday));
155 rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour));
156 rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min));
157 rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec));
158
159 rtc_write (RTC_CTL1_REG_ADDR, RTC_CTL1_BIT_2412);
160
161 return 0;
162 }
163
164 /*
165 * Reset the RTC
166 */
rtc_reset(void)167 void rtc_reset (void)
168 {
169 uchar buf[16];
170 uchar ctl2;
171
172 if (i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 16))
173 printf("Error reading from RTC\n");
174
175 ctl2 = rtc_read(RTC_CTL2_REG_ADDR);
176 ctl2 &= ~(RTC_CTL2_BIT_PON | RTC_CTL2_BIT_VDET);
177 ctl2 |= RTC_CTL2_BIT_XST | RTC_CTL2_BIT_VDSL;
178 rtc_write (RTC_CTL2_REG_ADDR, ctl2);
179 }
180
181 /*
182 * Helper functions
183 */
rtc_write(uchar reg,uchar val)184 static void rtc_write (uchar reg, uchar val)
185 {
186 uchar buf[2];
187 buf[0] = reg << 4;
188 buf[1] = val;
189 if (i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 0, buf, 2) != 0)
190 printf("Error writing to RTC\n");
191
192 }
193
194 #endif /* CONFIG_RTC_RX8025 && CONFIG_CMD_DATE */
195