1 /***************************************************************************
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
10 * adopted for HD300 by Marcin Bukat
11 * Copyright (C) 2009 by Bertrik Sikken
12 * Copyright (C) 2008 by Robert Kukla
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version 2
17 * of the License, or (at your option) any later version.
19 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
20 * KIND, either express or implied.
22 ****************************************************************************/
25 #include "i2c-coldfire.h"
27 /* Driver for the Seiko S35380A real-time clock chip with i2c interface
29 This driver was derived from rtc_s3539a.c and adapted for the MPIO HD300
36 #define REALTIME_DATA1 2
37 #define REALTIME_DATA2 3
40 #define CLOCK_CORR_REG 6
43 /* STATUS_REG1 flags */
44 #define STATUS_REG1_POC 0x80
45 #define STATUS_REG1_BLD 0x40
46 #define STATUS_REG1_INT2 0x20
47 #define STATUS_REG1_INT1 0x10
48 #define STATUS_REG1_SC1 0x08
49 #define STATUS_REG1_SC0 0x04
50 #define STATUS_REG1_H1224 0x02
51 #define STATUS_REG1_RESET 0x01
54 static void reverse_bits(unsigned char* v
, int size
)
56 static const unsigned char flipnibble
[] =
57 {0x00, 0x08, 0x04, 0x0C, 0x02, 0x0A, 0x06, 0x0E,
58 0x01, 0x09, 0x05, 0x0D, 0x03, 0x0B, 0x07, 0x0F};
61 for (i
= 0; i
< size
; i
++) {
62 v
[i
] = (flipnibble
[v
[i
] & 0x0F] << 4) |
63 flipnibble
[(v
[i
] >> 4) & 0x0F];
69 unsigned char status_reg
;
70 i2c_read(I2C_IFACE_1
, RTC_ADDR
| (STATUS_REG1
<<1), &status_reg
, 1);
72 if ( (status_reg
& STATUS_REG1_POC
) ||
73 (status_reg
& STATUS_REG1_BLD
) )
75 /* perform rtc reset*/
76 status_reg
|= STATUS_REG1_RESET
;
77 i2c_write(I2C_IFACE_1
, RTC_ADDR
| (STATUS_REG1
<<1), &status_reg
, 1);
81 int rtc_read_datetime(struct tm
*tm
)
87 ret
= i2c_read(I2C_IFACE_1
, RTC_ADDR
| (REALTIME_DATA1
<<1), buf
, sizeof(buf
));
88 reverse_bits(buf
, sizeof(buf
));
90 buf
[4] &= 0x3f; /* mask out p.m. flag */
92 for (i
= 0; i
< sizeof(buf
); i
++)
93 buf
[i
] = BCD2DEC(buf
[i
]);
100 tm
->tm_mon
= buf
[1] - 1;
101 tm
->tm_year
= buf
[0] + 100;
106 int rtc_write_datetime(const struct tm
*tm
)
108 unsigned char buf
[7];
114 buf
[4] = tm
->tm_hour
;
115 buf
[3] = tm
->tm_wday
;
116 buf
[2] = tm
->tm_mday
;
117 buf
[1] = tm
->tm_mon
+ 1;
118 buf
[0] = tm
->tm_year
- 100;
120 for (i
= 0; i
< sizeof(buf
); i
++)
121 buf
[i
] = DEC2BCD(buf
[i
]);
123 reverse_bits(buf
, sizeof(buf
));
124 ret
= i2c_write(I2C_IFACE_1
, RTC_ADDR
| (REALTIME_DATA1
<<1), buf
, sizeof(buf
));