xref: /openbmc/u-boot/drivers/rtc/pcf8563.c (revision 35546f6f2014282cc4f9772324b5588bd44a2938)
1  /*
2   * (C) Copyright 2001
3   * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4   *
5   * SPDX-License-Identifier:	GPL-2.0+
6   */
7  
8  /*
9   * Date & Time support for Philips PCF8563 RTC
10   */
11  
12  /* #define	DEBUG	*/
13  
14  #include <common.h>
15  #include <command.h>
16  #include <rtc.h>
17  #include <i2c.h>
18  
19  #if defined(CONFIG_CMD_DATE)
20  
21  static uchar rtc_read  (uchar reg);
22  static void  rtc_write (uchar reg, uchar val);
23  
24  /* ------------------------------------------------------------------------- */
25  
26  int rtc_get (struct rtc_time *tmp)
27  {
28  	int rel = 0;
29  	uchar sec, min, hour, mday, wday, mon_cent, year;
30  
31  	sec	= rtc_read (0x02);
32  	min	= rtc_read (0x03);
33  	hour	= rtc_read (0x04);
34  	mday	= rtc_read (0x05);
35  	wday	= rtc_read (0x06);
36  	mon_cent= rtc_read (0x07);
37  	year	= rtc_read (0x08);
38  
39  	debug ( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
40  		"hr: %02x min: %02x sec: %02x\n",
41  		year, mon_cent, mday, wday,
42  		hour, min, sec );
43  	debug ( "Alarms: wday: %02x day: %02x hour: %02x min: %02x\n",
44  		rtc_read (0x0C),
45  		rtc_read (0x0B),
46  		rtc_read (0x0A),
47  		rtc_read (0x09) );
48  
49  	if (sec & 0x80) {
50  		puts ("### Warning: RTC Low Voltage - date/time not reliable\n");
51  		rel = -1;
52  	}
53  
54  	tmp->tm_sec  = bcd2bin (sec  & 0x7F);
55  	tmp->tm_min  = bcd2bin (min  & 0x7F);
56  	tmp->tm_hour = bcd2bin (hour & 0x3F);
57  	tmp->tm_mday = bcd2bin (mday & 0x3F);
58  	tmp->tm_mon  = bcd2bin (mon_cent & 0x1F);
59  	tmp->tm_year = bcd2bin (year) + ((mon_cent & 0x80) ? 1900 : 2000);
60  	tmp->tm_wday = bcd2bin (wday & 0x07);
61  	tmp->tm_yday = 0;
62  	tmp->tm_isdst= 0;
63  
64  	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
65  		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
66  		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
67  
68  	return rel;
69  }
70  
71  int rtc_set (struct rtc_time *tmp)
72  {
73  	uchar century;
74  
75  	debug ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
76  		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
77  		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
78  
79  	rtc_write (0x08, bin2bcd(tmp->tm_year % 100));
80  
81  	century = (tmp->tm_year >= 2000) ? 0 : 0x80;
82  	rtc_write (0x07, bin2bcd(tmp->tm_mon) | century);
83  
84  	rtc_write (0x06, bin2bcd(tmp->tm_wday));
85  	rtc_write (0x05, bin2bcd(tmp->tm_mday));
86  	rtc_write (0x04, bin2bcd(tmp->tm_hour));
87  	rtc_write (0x03, bin2bcd(tmp->tm_min ));
88  	rtc_write (0x02, bin2bcd(tmp->tm_sec ));
89  
90  	return 0;
91  }
92  
93  void rtc_reset (void)
94  {
95  	/* clear all control & status registers */
96  	rtc_write (0x00, 0x00);
97  	rtc_write (0x01, 0x00);
98  	rtc_write (0x0D, 0x00);
99  
100  	/* clear Voltage Low bit */
101  	rtc_write (0x02, rtc_read (0x02) & 0x7F);
102  
103  	/* reset all alarms */
104  	rtc_write (0x09, 0x00);
105  	rtc_write (0x0A, 0x00);
106  	rtc_write (0x0B, 0x00);
107  	rtc_write (0x0C, 0x00);
108  }
109  
110  /* ------------------------------------------------------------------------- */
111  
112  static uchar rtc_read (uchar reg)
113  {
114  	return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg));
115  }
116  
117  static void rtc_write (uchar reg, uchar val)
118  {
119  	i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
120  }
121  
122  #endif
123