+/*
+ * (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)
+
+#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 */
projects / karo-tx-uboot.git / commitdiff