3 * Andrew May, Viasat Inc, amay@viasat.com
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of
8 * the License, or (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
22 * M41T11 Serial Access Timekeeper(R) SRAM
23 * can you believe a trademark on that?
34 I Don't have an example config file but this
35 is what should be done.
37 #define CONFIG_RTC_M41T11 1
38 #define CFG_I2C_RTC_ADDR 0x68
40 #define CFG_M41T11_EXT_CENTURY_DATA
42 #define CFG_M41T11_BASE_YEAR 2000
46 #if defined(CONFIG_RTC_M41T11) && defined(CFG_I2C_RTC_ADDR) && defined(CONFIG_CMD_DATE)
48 static unsigned bcd2bin (uchar n
)
50 return ((((n
>> 4) & 0x0F) * 10) + (n
& 0x0F));
53 static unsigned char bin2bcd (unsigned int n
)
55 return (((n
/ 10) << 4) | (n
% 10));
59 /* ------------------------------------------------------------------------- */
61 these are simple defines for the chip local to here so they aren't too
63 DAY/DATE aren't nice but that is how they are on the data sheet
65 #define RTC_SEC_ADDR 0x0
66 #define RTC_MIN_ADDR 0x1
67 #define RTC_HOUR_ADDR 0x2
68 #define RTC_DAY_ADDR 0x3
69 #define RTC_DATE_ADDR 0x4
70 #define RTC_MONTH_ADDR 0x5
71 #define RTC_YEARS_ADDR 0x6
75 #define RTC_CONTROL_ADDR 0x7
78 #ifndef CFG_M41T11_EXT_CENTURY_DATA
80 #define REG_CNT (RTC_REG_CNT+1)
83 you only get 00-99 for the year we will asume you
84 want from the year 2000 if you don't set the config
86 #ifndef CFG_M41T11_BASE_YEAR
87 #define CFG_M41T11_BASE_YEAR 2000
91 /* we will store extra year info in byte 9*/
92 #define M41T11_YEAR_DATA 0x8
93 #define M41T11_YEAR_SIZE 1
94 #define REG_CNT (RTC_REG_CNT+1+M41T11_YEAR_SIZE)
97 #define M41T11_STORAGE_SZ (64-REG_CNT)
99 void rtc_get (struct rtc_time
*tmp
)
101 uchar data
[RTC_REG_CNT
];
103 i2c_read(CFG_I2C_RTC_ADDR
, RTC_SEC_ADDR
, 1, data
, RTC_REG_CNT
);
105 if( data
[RTC_SEC_ADDR
] & 0x80 ){
106 printf( "m41t11 RTC Clock stopped!!!\n" );
108 tmp
->tm_sec
= bcd2bin (data
[RTC_SEC_ADDR
] & 0x7F);
109 tmp
->tm_min
= bcd2bin (data
[RTC_MIN_ADDR
] & 0x7F);
110 tmp
->tm_hour
= bcd2bin (data
[RTC_HOUR_ADDR
] & 0x3F);
111 tmp
->tm_mday
= bcd2bin (data
[RTC_DATE_ADDR
] & 0x3F);
112 tmp
->tm_mon
= bcd2bin (data
[RTC_MONTH_ADDR
]& 0x1F);
113 #ifndef CFG_M41T11_EXT_CENTURY_DATA
114 tmp
->tm_year
= CFG_M41T11_BASE_YEAR
115 + bcd2bin(data
[RTC_YEARS_ADDR
])
116 + ((data
[RTC_HOUR_ADDR
]&0x40) ? 100 : 0);
120 i2c_read(CFG_I2C_RTC_ADDR
, M41T11_YEAR_DATA
, 1, ¢
, M41T11_YEAR_SIZE
);
121 if( !(data
[RTC_HOUR_ADDR
] & 0x80) ){
122 printf( "m41t11 RTC: cann't keep track of years without CEB set\n" );
124 if( (cent
& 0x1) != ((data
[RTC_HOUR_ADDR
]&0x40)>>7) ){
125 /*century flip store off new year*/
127 i2c_write(CFG_I2C_RTC_ADDR
, M41T11_YEAR_DATA
, 1, ¢
, M41T11_YEAR_SIZE
);
129 tmp
->tm_year
=((int)cent
*100)+bcd2bin(data
[RTC_YEARS_ADDR
]);
132 tmp
->tm_wday
= bcd2bin (data
[RTC_DAY_ADDR
] & 0x07);
136 debug ( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
137 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
138 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
141 void rtc_set (struct rtc_time
*tmp
)
143 uchar data
[RTC_REG_CNT
];
145 debug ( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
146 tmp
->tm_year
, tmp
->tm_mon
, tmp
->tm_mday
, tmp
->tm_wday
,
147 tmp
->tm_hour
, tmp
->tm_min
, tmp
->tm_sec
);
149 data
[RTC_SEC_ADDR
] = bin2bcd(tmp
->tm_sec
) & 0x7F;/*just in case*/
150 data
[RTC_MIN_ADDR
] = bin2bcd(tmp
->tm_min
);
151 data
[RTC_HOUR_ADDR
] = bin2bcd(tmp
->tm_hour
) & 0x3F;/*handle cent stuff later*/
152 data
[RTC_DATE_ADDR
] = bin2bcd(tmp
->tm_mday
) & 0x3F;
153 data
[RTC_MONTH_ADDR
] = bin2bcd(tmp
->tm_mon
);
154 data
[RTC_DAY_ADDR
] = bin2bcd(tmp
->tm_wday
) & 0x07;
156 data
[RTC_HOUR_ADDR
] |= 0x80;/*we will always use CEB*/
158 data
[RTC_YEARS_ADDR
] = bin2bcd(tmp
->tm_year
%100);/*same thing either way*/
159 #ifndef CFG_M41T11_EXT_CENTURY_DATA
160 if( ((tmp
->tm_year
- CFG_M41T11_BASE_YEAR
) > 200) ||
161 (tmp
->tm_year
< CFG_M41T11_BASE_YEAR
) ){
162 printf( "m41t11 RTC setting year out of range!!need recompile\n" );
164 data
[RTC_HOUR_ADDR
] |= (tmp
->tm_year
- CFG_M41T11_BASE_YEAR
) > 100 ? 0x40 : 0;
168 cent
= tmp
->tm_year
? tmp
->tm_year
/ 100 : 0;
169 data
[RTC_HOUR_ADDR
] |= (cent
& 0x1) ? 0x40 : 0;
170 i2c_write(CFG_I2C_RTC_ADDR
, M41T11_YEAR_DATA
, 1, ¢
, M41T11_YEAR_SIZE
);
173 i2c_write(CFG_I2C_RTC_ADDR
, RTC_SEC_ADDR
, 1, data
, RTC_REG_CNT
);
176 void rtc_reset (void)
179 /* clear all control & status registers */
180 i2c_read(CFG_I2C_RTC_ADDR
, RTC_SEC_ADDR
, 1, &val
, 1);
181 val
= val
& 0x7F;/*make sure we are running*/
182 i2c_write(CFG_I2C_RTC_ADDR
, RTC_SEC_ADDR
, 1, &val
, RTC_REG_CNT
);
184 i2c_read(CFG_I2C_RTC_ADDR
, RTC_CONTROL_ADDR
, 1, &val
, 1);
185 val
= val
& 0x3F;/*turn off freq test keep calibration*/
186 i2c_write(CFG_I2C_RTC_ADDR
, RTC_CONTROL_ADDR
, 1, &val
, 1);
189 int rtc_store(int addr
, unsigned char* data
, int size
)
191 /*don't let things wrap onto the time on a write*/
192 if( (addr
+size
) >= M41T11_STORAGE_SZ
)
194 return i2c_write( CFG_I2C_RTC_ADDR
, REG_CNT
+addr
, 1, data
, size
);
197 int rtc_recall(int addr
, unsigned char* data
, int size
)
199 return i2c_read( CFG_I2C_RTC_ADDR
, REG_CNT
+addr
, 1, data
, size
);