Code Cleanup

Patch by Gary Jennejohn, 04 Oct 2004:
- fix I2C on at91rm9200
- add support for Ricoh RS5C372A RTC

1 files changed, 303 insertions, 0 deletions

diff --git a/rtc/rs5c372.c b/rtc/rs5c372.c
new file mode 100644
index 0000000..0f8ec62
--- /dev/null
+++ b/rtc/rs5c372.c
@@ -0,0 +1,303 @@
+/*
+ * rs5c372.c
+ *
+ * Device driver for Ricoh's Real Time Controller RS5C372A.
+ *
+ * Copyright (C) 2004 Gary Jennejohn garyj@denx.de
+ *
+ * Based in part in ds1307.c -
+ * (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 version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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
+ */
+
+#include <common.h>
+#include <command.h>
+#include <rtc.h>
+#include <i2c.h>
+
+#if defined(CONFIG_RTC_RS5C372A) && (CONFIG_COMMANDS & CFG_CMD_DATE)
+/*
+ * Reads are always done starting with register 15, which requires some
+ * jumping-through-hoops to access the data correctly.
+ *
+ * Writes are always done starting with register 0.
+ */
+
+#define DEBUG 0
+
+#if DEBUG
+static unsigned int rtc_debug = DEBUG;
+#else
+#define rtc_debug 0	/* gcc will remove all the debug code for us */
+#endif
+
+#ifndef CFG_I2C_RTC_ADDR
+#define CFG_I2C_RTC_ADDR 0x32
+#endif
+
+#define RS5C372_RAM_SIZE 0x10
+#define RATE_32000HZ	0x80	/* Rate Select 32.000KHz */
+#define RATE_32768HZ	0x00	/* Rate Select 32.768KHz */
+
+#define STATUS_XPT  0x10    /* data invalid because voltage was 0 */
+
+#define USE_24HOUR_MODE 0x20
+#define TWELVE_HOUR_MODE(n) ((((n) >> 5) & 1) == 0)
+#define HOURS_AP(n)	(((n) >> 5) & 1)
+#define HOURS_12(n)	bcd2bin((n) & 0x1F)
+#define HOURS_24(n)	bcd2bin((n) & 0x3F)
+
+
+static uchar bin2bcd (unsigned int n);
+static unsigned bcd2bin (uchar c);
+
+static int setup_done = 0;
+
+static int
+rs5c372_readram(char *buf, int len)
+{
+	int ret;
+
+	ret = i2c_read(CFG_I2C_RTC_ADDR, 0, 0, buf, len);
+	if (ret != 0) {
+		printf("%s: failed to read\n", __FUNCTION__);
+		return ret;
+	}
+
+	if (buf[0] & STATUS_XPT)
+		printf("### Warning: RTC lost power\n");
+
+	return ret;
+}
+
+static void
+rs5c372_enable(void)
+{
+	unsigned char buf[RS5C372_RAM_SIZE + 1];
+	int ret;
+
+
+	/* note that this returns reg. 15 in buf[1] */
+	ret = rs5c372_readram(&buf[1], RS5C372_RAM_SIZE);
+	if (ret != 0) {
+		printf("%s: failed\n", __FUNCTION__);
+		return;
+	}
+
+	buf[0] = 0;
+	/* we want to start writing at register 0 so we have to copy the */
+	/* register contents up one slot */
+	for (ret = 2; ret < 9; ret++)
+		buf[ret - 1] = buf[ret];
+	/* registers 0 to 6 (time values) are not touched */
+	buf[8] = RATE_32768HZ; /* reg. 7 */
+	buf[9] = 0; /* reg. 8 */
+	buf[10] = 0; /* reg. 9 */
+	buf[11] = 0; /* reg. 10 */
+	buf[12] = 0; /* reg. 11 */
+	buf[13] = 0; /* reg. 12 */
+	buf[14] = 0; /* reg. 13 */
+	buf[15] = 0; /* reg. 14 */
+	buf[16] = USE_24HOUR_MODE; /* reg. 15 */
+	ret = i2c_write(CFG_I2C_RTC_ADDR, 0, 0, buf, RS5C372_RAM_SIZE+1);
+	if (ret != 0) {
+		printf("%s: failed\n", __FUNCTION__);
+		return;
+	}
+	setup_done = 1;
+
+	return;
+}
+
+static void
+rs5c372_convert_to_time(struct rtc_time *dt, char *buf)
+{
+	/* buf[0] is register 15 */
+	dt->tm_sec = bcd2bin(buf[1]);
+	dt->tm_min = bcd2bin(buf[2]);
+
+	if (TWELVE_HOUR_MODE(buf[0])) {
+		dt->tm_hour = HOURS_12(buf[3]);
+		if (HOURS_AP(buf[3])) /* PM */
+			dt->tm_hour += 12;
+	} else /* 24-hour-mode */
+		dt->tm_hour = HOURS_24(buf[3]);
+
+	dt->tm_mday = bcd2bin(buf[5]);
+	dt->tm_mon = bcd2bin(buf[6]);
+	dt->tm_year = bcd2bin(buf[7]);
+	if (dt->tm_year >= 70)
+		dt->tm_year += 1900;
+	else
+		dt->tm_year += 2000;
+	/* 0 is Sunday */
+	dt->tm_wday = bcd2bin(buf[4] & 0x07);
+	dt->tm_yday = 0;
+	dt->tm_isdst= 0;
+
+	if(rtc_debug > 2) {
+		printf("rs5c372_convert_to_time: year = %d\n", dt->tm_year);
+		printf("rs5c372_convert_to_time: mon  = %d\n", dt->tm_mon);
+		printf("rs5c372_convert_to_time: mday = %d\n", dt->tm_mday);
+		printf("rs5c372_convert_to_time: hour = %d\n", dt->tm_hour);
+		printf("rs5c372_convert_to_time: min  = %d\n", dt->tm_min);
+		printf("rs5c372_convert_to_time: sec  = %d\n", dt->tm_sec);
+	}
+}
+
+/*
+ * Get the current time from the RTC
+ */
+void
+rtc_get (struct rtc_time *tmp)
+{
+	unsigned char buf[RS5C372_RAM_SIZE];
+	int ret;
+
+	if (!setup_done)
+		rs5c372_enable();
+
+	if (!setup_done)
+		return;
+
+	memset(buf, 0, sizeof(buf));
+
+	/* note that this returns reg. 15 in buf[0] */
+	ret = rs5c372_readram(buf, RS5C372_RAM_SIZE);
+	if (ret != 0) {
+		printf("%s: failed\n", __FUNCTION__);
+		return;
+	}
+
+	rs5c372_convert_to_time(tmp, buf);
+
+	return;
+}
+
+/*
+ * Set the RTC
+ */
+void
+rtc_set (struct rtc_time *tmp)
+{
+	unsigned char buf[8], reg15;
+	int ret;
+
+	if (!setup_done)
+		rs5c372_enable();
+
+	if (!setup_done)
+		return;
+
+	if(rtc_debug > 2) {
+		printf("rtc_set: tm_year = %d\n", tmp->tm_year);
+		printf("rtc_set: tm_mon	 = %d\n", tmp->tm_mon);
+		printf("rtc_set: tm_mday = %d\n", tmp->tm_mday);
+		printf("rtc_set: tm_hour = %d\n", tmp->tm_hour);
+		printf("rtc_set: tm_min	 = %d\n", tmp->tm_min);
+		printf("rtc_set: tm_sec	 = %d\n", tmp->tm_sec);
+	}
+
+	memset(buf, 0, sizeof(buf));
+
+	/* only read register 15 */
+	ret = i2c_read(CFG_I2C_RTC_ADDR, 0, 0, buf, 1);
+
+	if (ret == 0) {
+		/* need to save register 15 */
+		reg15 = buf[0];
+		buf[0] = 0;	/* register address on RS5C372 */
+		buf[1] = bin2bcd(tmp->tm_sec);
+		buf[2] = bin2bcd(tmp->tm_min);
+		/* need to handle 12 hour mode */
+		if (TWELVE_HOUR_MODE(reg15)) {
+			if (tmp->tm_hour >= 12) { /* PM */
+				/* 12 PM is a special case */
+				if (tmp->tm_hour == 12)
+					buf[3] = bin2bcd(tmp->tm_hour);
+				else
+					buf[3] = bin2bcd(tmp->tm_hour - 12);
+				buf[3] |= 0x20;
+			}
+		} else {
+			buf[3] = bin2bcd(tmp->tm_hour);
+		}
+
+		buf[4] = bin2bcd(tmp->tm_wday);
+		buf[5] = bin2bcd(tmp->tm_mday);
+		buf[6] = bin2bcd(tmp->tm_mon);
+		if (tmp->tm_year < 1970 || tmp->tm_year > 2069)
+			printf("WARNING: year should be between 1970 and 2069!\n");
+		buf[7] = bin2bcd(tmp->tm_year % 100);
+
+		ret = i2c_write(CFG_I2C_RTC_ADDR, 0, 0, buf, 8);
+		if (ret != 0)
+			printf("rs5c372_set_datetime(), i2c_master_send() returned %d\n",ret);
+	}
+
+	return;
+}
+
+/*
+ * Reset the RTC. We set the date back to 1970-01-01.
+ */
+void
+rtc_reset (void)
+{
+	struct rtc_time tmp;
+
+	if (!setup_done)
+		rs5c372_enable();
+
+	if (!setup_done)
+		return;
+
+	tmp.tm_year = 1970;
+	tmp.tm_mon = 1;
+	/* Jan. 1, 1970 was a Thursday */
+	tmp.tm_wday= 4;
+	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;
+}
+
+static unsigned int
+bcd2bin (unsigned char n)
+{
+	return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F));
+}
+
+static unsigned char
+bin2bcd (unsigned int n)
+{
+	return (((n / 10) << 4) | (n % 10));
+}
+#endif /* defined(CONFIG_RTC_RS5C372A) && (CONFIG_COMMANDS & CFG_CMD_DATE) */