1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2001
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 */
6
7 /*
8 * Date & Time support for Philips PCF8563 RTC
9 */
10
11 /* #define DEBUG */
12
13 #include <common.h>
14 #include <command.h>
15 #include <rtc.h>
16 #include <i2c.h>
17
18 static uchar rtc_read (uchar reg);
19 static void rtc_write (uchar reg, uchar val);
20
21 /* ------------------------------------------------------------------------- */
22
rtc_get(struct rtc_time * tmp)23 int rtc_get (struct rtc_time *tmp)
24 {
25 int rel = 0;
26 uchar sec, min, hour, mday, wday, mon_cent, year;
27
28 sec = rtc_read (0x02);
29 min = rtc_read (0x03);
30 hour = rtc_read (0x04);
31 mday = rtc_read (0x05);
32 wday = rtc_read (0x06);
33 mon_cent= rtc_read (0x07);
34 year = rtc_read (0x08);
35
36 debug ( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
37 "hr: %02x min: %02x sec: %02x\n",
38 year, mon_cent, mday, wday,
39 hour, min, sec );
40 debug ( "Alarms: wday: %02x day: %02x hour: %02x min: %02x\n",
41 rtc_read (0x0C),
42 rtc_read (0x0B),
43 rtc_read (0x0A),
44 rtc_read (0x09) );
45
46 if (sec & 0x80) {
47 puts ("### Warning: RTC Low Voltage - date/time not reliable\n");
48 rel = -1;
49 }
50
51 tmp->tm_sec = bcd2bin (sec & 0x7F);
52 tmp->tm_min = bcd2bin (min & 0x7F);
53 tmp->tm_hour = bcd2bin (hour & 0x3F);
54 tmp->tm_mday = bcd2bin (mday & 0x3F);
55 tmp->tm_mon = bcd2bin (mon_cent & 0x1F);
56 tmp->tm_year = bcd2bin (year) + ((mon_cent & 0x80) ? 1900 : 2000);
57 tmp->tm_wday = bcd2bin (wday & 0x07);
58 tmp->tm_yday = 0;
59 tmp->tm_isdst= 0;
60
61 debug ( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
62 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
63 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
64
65 return rel;
66 }
67
rtc_set(struct rtc_time * tmp)68 int rtc_set (struct rtc_time *tmp)
69 {
70 uchar century;
71
72 debug ( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
73 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
74 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
75
76 rtc_write (0x08, bin2bcd(tmp->tm_year % 100));
77
78 century = (tmp->tm_year >= 2000) ? 0 : 0x80;
79 rtc_write (0x07, bin2bcd(tmp->tm_mon) | century);
80
81 rtc_write (0x06, bin2bcd(tmp->tm_wday));
82 rtc_write (0x05, bin2bcd(tmp->tm_mday));
83 rtc_write (0x04, bin2bcd(tmp->tm_hour));
84 rtc_write (0x03, bin2bcd(tmp->tm_min ));
85 rtc_write (0x02, bin2bcd(tmp->tm_sec ));
86
87 return 0;
88 }
89
rtc_reset(void)90 void rtc_reset (void)
91 {
92 /* clear all control & status registers */
93 rtc_write (0x00, 0x00);
94 rtc_write (0x01, 0x00);
95 rtc_write (0x0D, 0x00);
96
97 /* clear Voltage Low bit */
98 rtc_write (0x02, rtc_read (0x02) & 0x7F);
99
100 /* reset all alarms */
101 rtc_write (0x09, 0x00);
102 rtc_write (0x0A, 0x00);
103 rtc_write (0x0B, 0x00);
104 rtc_write (0x0C, 0x00);
105 }
106
107 /* ------------------------------------------------------------------------- */
108
rtc_read(uchar reg)109 static uchar rtc_read (uchar reg)
110 {
111 return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg));
112 }
113
rtc_write(uchar reg,uchar val)114 static void rtc_write (uchar reg, uchar val)
115 {
116 i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
117 }
118