2 * (C) Copyright 2001-2008
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4 * Keith Outwater, keith_outwater@mvis.com`
6 * SPDX-License-Identifier: GPL-2.0+
10 * Date & Time support (no alarms) for Dallas Semiconductor (now Maxim)
11 * DS1337 Real Time Clock (RTC).
19 #if defined(CONFIG_CMD_DATE)
22 * RTC register addresses
24 #if defined CONFIG_RTC_DS1337
25 #define RTC_SEC_REG_ADDR 0x0
26 #define RTC_MIN_REG_ADDR 0x1
27 #define RTC_HR_REG_ADDR 0x2
28 #define RTC_DAY_REG_ADDR 0x3
29 #define RTC_DATE_REG_ADDR 0x4
30 #define RTC_MON_REG_ADDR 0x5
31 #define RTC_YR_REG_ADDR 0x6
32 #define RTC_CTL_REG_ADDR 0x0e
33 #define RTC_STAT_REG_ADDR 0x0f
34 #define RTC_TC_REG_ADDR 0x10
35 #elif defined CONFIG_RTC_DS1388
36 #define RTC_SEC_REG_ADDR 0x1
37 #define RTC_MIN_REG_ADDR 0x2
38 #define RTC_HR_REG_ADDR 0x3
39 #define RTC_DAY_REG_ADDR 0x4
40 #define RTC_DATE_REG_ADDR 0x5
41 #define RTC_MON_REG_ADDR 0x6
42 #define RTC_YR_REG_ADDR 0x7
43 #define RTC_CTL_REG_ADDR 0x0c
44 #define RTC_STAT_REG_ADDR 0x0b
45 #define RTC_TC_REG_ADDR 0x0a
49 * RTC control register bits
51 #define RTC_CTL_BIT_A1IE 0x1 /* Alarm 1 interrupt enable */
52 #define RTC_CTL_BIT_A2IE 0x2 /* Alarm 2 interrupt enable */
53 #define RTC_CTL_BIT_INTCN 0x4 /* Interrupt control */
54 #define RTC_CTL_BIT_RS1 0x8 /* Rate select 1 */
55 #define RTC_CTL_BIT_RS2 0x10 /* Rate select 2 */
56 #define RTC_CTL_BIT_DOSC 0x80 /* Disable Oscillator */
59 * RTC status register bits
61 #define RTC_STAT_BIT_A1F 0x1 /* Alarm 1 flag */
62 #define RTC_STAT_BIT_A2F 0x2 /* Alarm 2 flag */
63 #define RTC_STAT_BIT_OSF 0x80 /* Oscillator stop flag */
66 static uchar
rtc_read (uchar reg
);
67 static void rtc_write (uchar reg
, uchar val
);
70 * Get the current time from the RTC
72 int rtc_get (struct rtc_time
*tmp
)
75 uchar sec
, min
, hour
, mday
, wday
, mon_cent
, year
, control
, status
;
77 control
= rtc_read (RTC_CTL_REG_ADDR
);
78 status
= rtc_read (RTC_STAT_REG_ADDR
);
79 sec
= rtc_read (RTC_SEC_REG_ADDR
);
80 min
= rtc_read (RTC_MIN_REG_ADDR
);
81 hour
= rtc_read (RTC_HR_REG_ADDR
);
82 wday
= rtc_read (RTC_DAY_REG_ADDR
);
83 mday
= rtc_read (RTC_DATE_REG_ADDR
);
84 mon_cent
= rtc_read (RTC_MON_REG_ADDR
);
85 year
= rtc_read (RTC_YR_REG_ADDR
);
87 /* No century bit, assume year 2000 */
88 #ifdef CONFIG_RTC_DS1388
92 debug("Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
93 "hr: %02x min: %02x sec: %02x control: %02x status: %02x\n",
94 year
, mon_cent
, mday
, wday
, hour
, min
, sec
, control
, status
);
96 if (status
& RTC_STAT_BIT_OSF
) {
97 printf ("### Warning: RTC oscillator has stopped\n");
98 /* clear the OSF flag */
99 rtc_write (RTC_STAT_REG_ADDR
,
100 rtc_read (RTC_STAT_REG_ADDR
) & ~RTC_STAT_BIT_OSF
);
104 tmp
->tm_sec
= bcd2bin (sec
& 0x7F);
105 tmp
->tm_min
= bcd2bin (min
& 0x7F);
106 tmp
->tm_hour
= bcd2bin (hour
& 0x3F);
107 tmp
->tm_mday
= bcd2bin (mday
& 0x3F);
108 tmp
->tm_mon
= bcd2bin (mon_cent
& 0x1F);
109 tmp
->tm_year
= bcd2bin (year
) + ((mon_cent
& 0x80) ? 2000 : 1900);
110 tmp
->tm_wday
= bcd2bin ((wday
- 1) & 0x07);
114 debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
115 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
116 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
125 int rtc_set (struct rtc_time
*tmp
)
129 debug("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
130 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
131 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
133 rtc_write (RTC_YR_REG_ADDR
, bin2bcd (tmp
->tm_year
% 100));
135 century
= (tmp
->tm_year
>= 2000) ? 0x80 : 0;
136 rtc_write (RTC_MON_REG_ADDR
, bin2bcd (tmp
->tm_mon
) | century
);
138 rtc_write (RTC_DAY_REG_ADDR
, bin2bcd (tmp
->tm_wday
+ 1));
139 rtc_write (RTC_DATE_REG_ADDR
, bin2bcd (tmp
->tm_mday
));
140 rtc_write (RTC_HR_REG_ADDR
, bin2bcd (tmp
->tm_hour
));
141 rtc_write (RTC_MIN_REG_ADDR
, bin2bcd (tmp
->tm_min
));
142 rtc_write (RTC_SEC_REG_ADDR
, bin2bcd (tmp
->tm_sec
));
149 * Reset the RTC. We also enable the oscillator output on the
150 * SQW/INTB* pin and program it for 32,768 Hz output. Note that
151 * according to the datasheet, turning on the square wave output
152 * increases the current drain on the backup battery from about
153 * 600 nA to 2uA. Define CONFIG_RTC_DS1337_NOOSC if you wish to turn
154 * off the OSC output.
157 #ifdef CONFIG_RTC_DS1337_NOOSC
158 #define RTC_DS1337_RESET_VAL \
159 (RTC_CTL_BIT_INTCN | RTC_CTL_BIT_RS1 | RTC_CTL_BIT_RS2)
161 #define RTC_DS1337_RESET_VAL (RTC_CTL_BIT_RS1 | RTC_CTL_BIT_RS2)
163 void rtc_reset (void)
165 #ifdef CONFIG_RTC_DS1337
166 rtc_write (RTC_CTL_REG_ADDR
, RTC_DS1337_RESET_VAL
);
167 #elif defined CONFIG_RTC_DS1388
168 rtc_write(RTC_CTL_REG_ADDR
, 0x0); /* hw default */
170 #ifdef CONFIG_RTC_DS1339_TCR_VAL
171 rtc_write (RTC_TC_REG_ADDR
, CONFIG_RTC_DS1339_TCR_VAL
);
173 #ifdef CONFIG_RTC_DS1388_TCR_VAL
174 rtc_write(RTC_TC_REG_ADDR
, CONFIG_RTC_DS1388_TCR_VAL
);
184 uchar
rtc_read (uchar reg
)
186 return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR
, reg
));
190 static void rtc_write (uchar reg
, uchar val
)
192 i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR
, reg
, val
);