3 * Stefan Roese, DENX Software Engineering, sr@denx.de.
5 * based on a the Linux rtc-m41t80.c driver which is:
6 * Alexander Bigga <ab@mycable.de>, 2006 (c) mycable GmbH
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 STMicroelectronics M41T62
35 #if defined(CONFIG_CMD_DATE)
37 #define M41T62_REG_SSEC 0
38 #define M41T62_REG_SEC 1
39 #define M41T62_REG_MIN 2
40 #define M41T62_REG_HOUR 3
41 #define M41T62_REG_WDAY 4
42 #define M41T62_REG_DAY 5
43 #define M41T62_REG_MON 6
44 #define M41T62_REG_YEAR 7
45 #define M41T62_REG_ALARM_MON 0xa
46 #define M41T62_REG_ALARM_DAY 0xb
47 #define M41T62_REG_ALARM_HOUR 0xc
48 #define M41T62_REG_ALARM_MIN 0xd
49 #define M41T62_REG_ALARM_SEC 0xe
50 #define M41T62_REG_FLAGS 0xf
52 #define M41T62_DATETIME_REG_SIZE (M41T62_REG_YEAR + 1)
53 #define M41T62_ALARM_REG_SIZE \
54 (M41T62_REG_ALARM_SEC + 1 - M41T62_REG_ALARM_MON)
56 #define M41T62_SEC_ST (1 << 7) /* ST: Stop Bit */
57 #define M41T62_ALMON_AFE (1 << 7) /* AFE: AF Enable Bit */
58 #define M41T62_ALMON_SQWE (1 << 6) /* SQWE: SQW Enable Bit */
59 #define M41T62_ALHOUR_HT (1 << 6) /* HT: Halt Update Bit */
60 #define M41T62_FLAGS_AF (1 << 6) /* AF: Alarm Flag Bit */
61 #define M41T62_FLAGS_BATT_LOW (1 << 4) /* BL: Battery Low Bit */
63 #define M41T62_FEATURE_HT (1 << 0)
64 #define M41T62_FEATURE_BL (1 << 1)
66 #define M41T80_ALHOUR_HT (1 << 6) /* HT: Halt Update Bit */
68 int rtc_get(struct rtc_time *tm)
70 u8 buf[M41T62_DATETIME_REG_SIZE];
72 i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, buf, M41T62_DATETIME_REG_SIZE);
74 debug("%s: raw read data - sec=%02x, min=%02x, hr=%02x, "
75 "mday=%02x, mon=%02x, year=%02x, wday=%02x, y2k=%02x\n",
77 buf[0], buf[1], buf[2], buf[3],
78 buf[4], buf[5], buf[6], buf[7]);
80 tm->tm_sec = bcd2bin(buf[M41T62_REG_SEC] & 0x7f);
81 tm->tm_min = bcd2bin(buf[M41T62_REG_MIN] & 0x7f);
82 tm->tm_hour = bcd2bin(buf[M41T62_REG_HOUR] & 0x3f);
83 tm->tm_mday = bcd2bin(buf[M41T62_REG_DAY] & 0x3f);
84 tm->tm_wday = buf[M41T62_REG_WDAY] & 0x07;
85 tm->tm_mon = bcd2bin(buf[M41T62_REG_MON] & 0x1f);
87 /* assume 20YY not 19YY, and ignore the Century Bit */
88 /* U-Boot needs to add 1900 here */
89 tm->tm_year = bcd2bin(buf[M41T62_REG_YEAR]) + 100 + 1900;
91 debug("%s: tm is secs=%d, mins=%d, hours=%d, "
92 "mday=%d, mon=%d, year=%d, wday=%d\n",
94 tm->tm_sec, tm->tm_min, tm->tm_hour,
95 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
100 int rtc_set(struct rtc_time *tm)
102 u8 buf[M41T62_DATETIME_REG_SIZE];
104 debug("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
105 tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
106 tm->tm_hour, tm->tm_min, tm->tm_sec);
108 i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, buf, M41T62_DATETIME_REG_SIZE);
110 /* Merge time-data and register flags into buf[0..7] */
111 buf[M41T62_REG_SSEC] = 0;
112 buf[M41T62_REG_SEC] =
113 bin2bcd(tm->tm_sec) | (buf[M41T62_REG_SEC] & ~0x7f);
114 buf[M41T62_REG_MIN] =
115 bin2bcd(tm->tm_min) | (buf[M41T62_REG_MIN] & ~0x7f);
116 buf[M41T62_REG_HOUR] =
117 bin2bcd(tm->tm_hour) | (buf[M41T62_REG_HOUR] & ~0x3f) ;
118 buf[M41T62_REG_WDAY] =
119 (tm->tm_wday & 0x07) | (buf[M41T62_REG_WDAY] & ~0x07);
120 buf[M41T62_REG_DAY] =
121 bin2bcd(tm->tm_mday) | (buf[M41T62_REG_DAY] & ~0x3f);
122 buf[M41T62_REG_MON] =
123 bin2bcd(tm->tm_mon) | (buf[M41T62_REG_MON] & ~0x1f);
124 /* assume 20YY not 19YY */
125 buf[M41T62_REG_YEAR] = bin2bcd(tm->tm_year % 100);
127 if (i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, buf, M41T62_DATETIME_REG_SIZE)) {
128 printf("I2C write failed in %s()\n", __func__);
140 * M41T82: Make sure HT (Halt Update) bit is cleared.
141 * This bit is 0 in M41T62 so its save to clear it always.
143 i2c_read(CONFIG_SYS_I2C_RTC_ADDR, M41T62_REG_ALARM_HOUR, 1, &val, 1);
144 val &= ~M41T80_ALHOUR_HT;
145 i2c_write(CONFIG_SYS_I2C_RTC_ADDR, M41T62_REG_ALARM_HOUR, 1, &val, 1);