* Patches by David Müller, 31 Jan 2003:

  - minimal setup for CardBus bridges
  - add EEPROM read/write support in the CS8900 driver
  - add support for the builtin I2C controller in the Samsung s3c24x0 chips
  - add support for  MPL's VCMA9 (Samsung s3c2410 based) board

* Patch by Steven Scholz, 04 Feb 2003:
  add support for RTC DS1307

* Patch by Reinhard Meyer, 5 Feb 2003:
  fix PLPRCR/SCCR init sequence on 8xx to allow for
  changes of EBDF by software

* Patch by Vladimir Gurevich, 07 Feb 2003:
  "API-compatibility patch" for 4xx I2C driver

1 files changed, 203 insertions, 0 deletions

diff --git a/rtc/ds1307.c b/rtc/ds1307.c
new file mode 100644
index 0000000000..247494c34d
--- /dev/null
+++ b/rtc/ds1307.c
@@ -0,0 +1,203 @@
+/*
+ * (C) Copyright 2001, 2002, 2003
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ * Keith Outwater, keith_outwater@mvis.com`
+ * Steven Scholz, steven.scholz@imc-berlin.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 (no alarms) for Dallas Semiconductor (now Maxim)
+ * DS1307 Real Time Clock (RTC).
+ *
+ * based on ds1337.c
+ */
+
+#include <common.h>
+#include <command.h>
+#include <rtc.h>
+#include <i2c.h>
+
+#if defined(CONFIG_RTC_DS1307) && (CONFIG_COMMANDS & CFG_CMD_DATE)
+
+/*---------------------------------------------------------------------*/
+#undef DEBUG_RTC
+
+#ifdef DEBUG_RTC
+#define DEBUGR(fmt,args...) printf(fmt ,##args)
+#else
+#define DEBUGR(fmt,args...)
+#endif
+/*---------------------------------------------------------------------*/
+
+#ifndef CFG_I2C_RTC_ADDR
+# define CFG_I2C_RTC_ADDR	0x68
+#endif
+
+#if CFG_I2C_SPEED > 100000
+# error The DS1307 is specified only up to 100kHz!
+#endif
+
+/*
+ * RTC register addresses
+ */
+#define RTC_SEC_REG_ADDR	0x00
+#define RTC_MIN_REG_ADDR	0x01
+#define RTC_HR_REG_ADDR		0x02
+#define RTC_DAY_REG_ADDR	0x03
+#define RTC_DATE_REG_ADDR	0x04
+#define RTC_MON_REG_ADDR	0x05
+#define RTC_YR_REG_ADDR		0x06
+#define RTC_CTL_REG_ADDR	0x07
+
+#define RTC_SEC_BIT_CH		0x80	/* Clock Halt (in Register 0)   */
+
+#define RTC_CTL_BIT_RS0		0x01	/* Rate select 0                */
+#define RTC_CTL_BIT_RS1		0x02	/* Rate select 1                */
+#define RTC_CTL_BIT_SQWE	0x10	/* Square Wave Enable           */
+#define RTC_CTL_BIT_OUT		0x80	/* Output Control               */
+
+static uchar rtc_read (uchar reg);
+static void rtc_write (uchar reg, uchar val);
+static uchar bin2bcd (unsigned int n);
+static unsigned bcd2bin (uchar c);
+
+/*
+ * Get the current time from the RTC
+ */
+void rtc_get (struct rtc_time *tmp)
+{
+	uchar sec, min, hour, mday, wday, mon, year;
+
+	sec = rtc_read (RTC_SEC_REG_ADDR);
+	min = rtc_read (RTC_MIN_REG_ADDR);
+	hour = rtc_read (RTC_HR_REG_ADDR);
+	wday = rtc_read (RTC_DAY_REG_ADDR);
+	mday = rtc_read (RTC_DATE_REG_ADDR);
+	mon = rtc_read (RTC_MON_REG_ADDR);
+	year = rtc_read (RTC_YR_REG_ADDR);
+
+	DEBUGR ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x "
+		"hr: %02x min: %02x sec: %02x\n",
+		year, mon, mday, wday, hour, min, sec);
+
+	if (sec & RTC_SEC_BIT_CH) {
+		printf ("### Warning: RTC oscillator has stopped\n");
+		/* clear the CH flag */
+		rtc_write (RTC_SEC_REG_ADDR,
+			   rtc_read (RTC_SEC_REG_ADDR) & ~RTC_SEC_BIT_CH);
+	}
+	
+	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 (year) >= 70 ? 1900 : 2000);
+	tmp->tm_wday = bcd2bin ((wday - 1) & 0x07);
+	tmp->tm_yday = 0;
+	tmp->tm_isdst= 0;
+
+	DEBUGR ("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);
+}
+
+
+/*
+ * Set the RTC
+ */
+void rtc_set (struct rtc_time *tmp)
+{
+	DEBUGR ("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);
+
+	if (tmp->tm_year < 1970 || tmp->tm_year > 2069)
+		printf("WARNING: year should be between 1970 and 2069!\n");
+		
+	rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100));
+	rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon));
+	rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday + 1));
+	rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday));
+	rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour));
+	rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min));
+	rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec));
+}
+
+
+/*
+ * Reset the RTC. We setting the date back to 1970-01-01. 
+ * We also enable the oscillator output on the SQW/OUT pin and program 
+ * it for 32,768 Hz output. Note that according to the datasheet, turning
+ * on the square wave output increases the current drain on the backup
+ * battery to something between 480nA and 800nA.
+ */
+void rtc_reset (void)
+{
+	struct rtc_time tmp;
+
+	rtc_write (RTC_SEC_REG_ADDR, 0x00);	/* clearing Clock Halt	*/
+	rtc_write (RTC_CTL_REG_ADDR, RTC_CTL_BIT_SQWE | RTC_CTL_BIT_RS1 | RTC_CTL_BIT_RS0);
+
+	tmp.tm_year = 1970;
+	tmp.tm_mon = 1;
+	tmp.tm_mday= 1;
+	tmp.tm_hour = 0;
+	tmp.tm_min = 0;
+	tmp.tm_sec = 0;
+
+	rtc_set(&tmp);
+
+	printf ( "RTC:   %4d-%02d-%02d %2d:%02d:%02d UTC\n",
+		tmp.tm_year, tmp.tm_mon, tmp.tm_mday,
+		tmp.tm_hour, tmp.tm_min, tmp.tm_sec);
+
+	return;
+}
+
+
+/*
+ * Helper functions
+ */
+
+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);
+}
+
+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));
+}
+
+#endif /* CONFIG_RTC_DS1307 && (CFG_COMMANDS & CFG_CMD_DATE) */