/* * (C) Copyright 2004 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. * * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ /* * Date & Time support for MAXIM MAX6900 RTC */ /* #define DEBUG */ #include <common.h> #include <command.h> #include <rtc.h> #include <i2c.h> #if defined(CONFIG_RTC_MAX6900) && ((CONFIG_COMMANDS & CFG_CMD_DATE) || defined(CONFIG_CMD_DATE)) #ifndef CFG_I2C_RTC_ADDR #define CFG_I2C_RTC_ADDR 0x50 #endif /* ------------------------------------------------------------------------- */ static uchar rtc_read (uchar reg) { return (i2c_reg_read (CFG_I2C_RTC_ADDR, reg)); } static void rtc_write (uchar reg, uchar val) { i2c_reg_write (CFG_I2C_RTC_ADDR, reg, val); udelay(2500); } static unsigned bcd2bin (uchar n) { return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F)); } static unsigned char bin2bcd (unsigned int n) { return (((n / 10) << 4) | (n % 10)); } /* ------------------------------------------------------------------------- */ void rtc_get (struct rtc_time *tmp) { uchar sec, min, hour, mday, wday, mon, cent, year; int retry = 1; do { sec = rtc_read (0x80); min = rtc_read (0x82); hour = rtc_read (0x84); mday = rtc_read (0x86); mon = rtc_read (0x88); wday = rtc_read (0x8a); year = rtc_read (0x8c); cent = rtc_read (0x92); /* * Check for seconds rollover */ if ((sec != 59) || (rtc_read(0x80) == sec)){ retry = 0; } } while (retry); debug ( "Get RTC year: %02x mon: %02x cent: %02x mday: %02x wday: %02x " "hr: %02x min: %02x sec: %02x\n", year, mon, cent, mday, wday, hour, min, sec ); tmp->tm_sec = bcd2bin (sec & 0x7F); tmp->tm_min = bcd2bin (min & 0x7F); tmp->tm_hour = bcd2bin (hour & 0x3F); tmp->tm_mday = bcd2bin (mday & 0x3F); tmp->tm_mon = bcd2bin (mon & 0x1F); tmp->tm_year = bcd2bin (year) + bcd2bin(cent) * 100; tmp->tm_wday = bcd2bin (wday & 0x07); tmp->tm_yday = 0; tmp->tm_isdst= 0; debug ( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, tmp->tm_hour, tmp->tm_min, tmp->tm_sec); } void rtc_set (struct rtc_time *tmp) { debug ( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, tmp->tm_hour, tmp->tm_min, tmp->tm_sec); rtc_write (0x9E, 0x00); rtc_write (0x80, 0); /* Clear seconds to ensure no rollover */ rtc_write (0x92, bin2bcd(tmp->tm_year / 100)); rtc_write (0x8c, bin2bcd(tmp->tm_year % 100)); rtc_write (0x8a, bin2bcd(tmp->tm_wday)); rtc_write (0x88, bin2bcd(tmp->tm_mon)); rtc_write (0x86, bin2bcd(tmp->tm_mday)); rtc_write (0x84, bin2bcd(tmp->tm_hour)); rtc_write (0x82, bin2bcd(tmp->tm_min )); rtc_write (0x80, bin2bcd(tmp->tm_sec )); } void rtc_reset (void) { } #endif /* CONFIG_RTC_MAX6900 && CFG_CMD_DATE */