3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 * See file CREDITS for list of people who contributed to this
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25 * Date & Time support for MAXIM MAX6900 RTC
35 #if defined(CONFIG_RTC_MAX6900) && defined(CONFIG_CMD_DATE)
37 #ifndef CFG_I2C_RTC_ADDR
38 #define CFG_I2C_RTC_ADDR 0x50
41 /* ------------------------------------------------------------------------- */
43 static uchar
rtc_read (uchar reg
)
45 return (i2c_reg_read (CFG_I2C_RTC_ADDR
, reg
));
48 static void rtc_write (uchar reg
, uchar val
)
50 i2c_reg_write (CFG_I2C_RTC_ADDR
, reg
, val
);
54 static unsigned bcd2bin (uchar n
)
56 return ((((n
>> 4) & 0x0F) * 10) + (n
& 0x0F));
59 static unsigned char bin2bcd (unsigned int n
)
61 return (((n
/ 10) << 4) | (n
% 10));
64 /* ------------------------------------------------------------------------- */
66 int rtc_get (struct rtc_time
*tmp
)
68 uchar sec
, min
, hour
, mday
, wday
, mon
, cent
, year
;
72 sec
= rtc_read (0x80);
73 min
= rtc_read (0x82);
74 hour
= rtc_read (0x84);
75 mday
= rtc_read (0x86);
76 mon
= rtc_read (0x88);
77 wday
= rtc_read (0x8a);
78 year
= rtc_read (0x8c);
79 cent
= rtc_read (0x92);
81 * Check for seconds rollover
83 if ((sec
!= 59) || (rtc_read(0x80) == sec
)){
88 debug ( "Get RTC year: %02x mon: %02x cent: %02x mday: %02x wday: %02x "
89 "hr: %02x min: %02x sec: %02x\n",
90 year
, mon
, cent
, mday
, wday
,
93 tmp
->tm_sec
= bcd2bin (sec
& 0x7F);
94 tmp
->tm_min
= bcd2bin (min
& 0x7F);
95 tmp
->tm_hour
= bcd2bin (hour
& 0x3F);
96 tmp
->tm_mday
= bcd2bin (mday
& 0x3F);
97 tmp
->tm_mon
= bcd2bin (mon
& 0x1F);
98 tmp
->tm_year
= bcd2bin (year
) + bcd2bin(cent
) * 100;
99 tmp
->tm_wday
= bcd2bin (wday
& 0x07);
103 debug ( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
104 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
105 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
110 void rtc_set (struct rtc_time
*tmp
)
113 debug ( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
114 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
115 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
117 rtc_write (0x9E, 0x00);
118 rtc_write (0x80, 0); /* Clear seconds to ensure no rollover */
119 rtc_write (0x92, bin2bcd(tmp
->tm_year
/ 100));
120 rtc_write (0x8c, bin2bcd(tmp
->tm_year
% 100));
121 rtc_write (0x8a, bin2bcd(tmp
->tm_wday
));
122 rtc_write (0x88, bin2bcd(tmp
->tm_mon
));
123 rtc_write (0x86, bin2bcd(tmp
->tm_mday
));
124 rtc_write (0x84, bin2bcd(tmp
->tm_hour
));
125 rtc_write (0x82, bin2bcd(tmp
->tm_min
));
126 rtc_write (0x80, bin2bcd(tmp
->tm_sec
));
129 void rtc_reset (void)