[people/ms/u-boot.git] / drivers / rtc / 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 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 and DS1338 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) || defined(CONFIG_RTC_DS1338) ) && \
    defined(CONFIG_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 defined(CONFIG_RTC_DS1307) && (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
 */
int rtc_get (struct rtc_time *tmp)
{
	int rel = 0;
	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);
		rel = -1;
	}

	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);

	return rel;
}


/*
 * 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
Commit	Line	Data
1cb8e980 WD	1	/*
	2	* (C) Copyright 2001, 2002, 2003
	3	* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
	4	* Keith Outwater, keith_outwater@mvis.com`
	5	* Steven Scholz, steven.scholz@imc-berlin.de
	6	*
	7	* See file CREDITS for list of people who contributed to this
	8	* project.
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public License as
	12	* published by the Free Software Foundation; either version 2 of
	13	* the License, or (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	* GNU General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to the Free Software
	22	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	23	* MA 02111-1307 USA
	24	*/
	25
	26	/*
	27	* Date & Time support (no alarms) for Dallas Semiconductor (now Maxim)
7f70e853	28	* DS1307 and DS1338 Real Time Clock (RTC).
1cb8e980 WD	29	*
	30	* based on ds1337.c
	31	*/
	32
	33	#include <common.h>
	34	#include <command.h>
	35	#include <rtc.h>
	36	#include <i2c.h>
	37
7f70e853	38	#if (defined(CONFIG_RTC_DS1307) \|\| defined(CONFIG_RTC_DS1338) ) && \
a593814f	39	defined(CONFIG_CMD_DATE)
1cb8e980 WD	40
	41	/---------------------------------------------------------------------/
	42	#undef DEBUG_RTC
	43
	44	#ifdef DEBUG_RTC
	45	#define DEBUGR(fmt,args...) printf(fmt ,##args)
	46	#else
	47	#define DEBUGR(fmt,args...)
	48	#endif
	49	/---------------------------------------------------------------------/
	50
	51	#ifndef CFG_I2C_RTC_ADDR
	52	# define CFG_I2C_RTC_ADDR 0x68
	53	#endif
	54
3d3befa7	55	#if defined(CONFIG_RTC_DS1307) && (CFG_I2C_SPEED > 100000)
1cb8e980 WD	56	# error The DS1307 is specified only up to 100kHz!
	57	#endif
	58
	59	/*
	60	* RTC register addresses
	61	*/
	62	#define RTC_SEC_REG_ADDR 0x00
	63	#define RTC_MIN_REG_ADDR 0x01
	64	#define RTC_HR_REG_ADDR 0x02
	65	#define RTC_DAY_REG_ADDR 0x03
	66	#define RTC_DATE_REG_ADDR 0x04
	67	#define RTC_MON_REG_ADDR 0x05
	68	#define RTC_YR_REG_ADDR 0x06
	69	#define RTC_CTL_REG_ADDR 0x07
	70
	71	#define RTC_SEC_BIT_CH 0x80 /* Clock Halt (in Register 0) */
	72
	73	#define RTC_CTL_BIT_RS0 0x01 /* Rate select 0 */
	74	#define RTC_CTL_BIT_RS1 0x02 /* Rate select 1 */
	75	#define RTC_CTL_BIT_SQWE 0x10 /* Square Wave Enable */
	76	#define RTC_CTL_BIT_OUT 0x80 /* Output Control */
	77
	78	static uchar rtc_read (uchar reg);
	79	static void rtc_write (uchar reg, uchar val);
	80	static uchar bin2bcd (unsigned int n);
	81	static unsigned bcd2bin (uchar c);
	82
	83	/*
	84	* Get the current time from the RTC
	85	*/
b73a19e1	86	int rtc_get (struct rtc_time *tmp)
1cb8e980	87	{
b73a19e1	88	int rel = 0;
1cb8e980 WD	89	uchar sec, min, hour, mday, wday, mon, year;
	90
	91	sec = rtc_read (RTC_SEC_REG_ADDR);
	92	min = rtc_read (RTC_MIN_REG_ADDR);
	93	hour = rtc_read (RTC_HR_REG_ADDR);
	94	wday = rtc_read (RTC_DAY_REG_ADDR);
	95	mday = rtc_read (RTC_DATE_REG_ADDR);
	96	mon = rtc_read (RTC_MON_REG_ADDR);
	97	year = rtc_read (RTC_YR_REG_ADDR);
	98
	99	DEBUGR ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x "
	100	"hr: %02x min: %02x sec: %02x\n",
	101	year, mon, mday, wday, hour, min, sec);
	102
	103	if (sec & RTC_SEC_BIT_CH) {
	104	printf ("### Warning: RTC oscillator has stopped\n");
	105	/* clear the CH flag */
	106	rtc_write (RTC_SEC_REG_ADDR,
	107	rtc_read (RTC_SEC_REG_ADDR) & ~RTC_SEC_BIT_CH);
b73a19e1	108	rel = -1;
1cb8e980	109	}
8bde7f77	110
1cb8e980 WD	111	tmp->tm_sec = bcd2bin (sec & 0x7F);
	112	tmp->tm_min = bcd2bin (min & 0x7F);
	113	tmp->tm_hour = bcd2bin (hour & 0x3F);
	114	tmp->tm_mday = bcd2bin (mday & 0x3F);
	115	tmp->tm_mon = bcd2bin (mon & 0x1F);
	116	tmp->tm_year = bcd2bin (year) + ( bcd2bin (year) >= 70 ? 1900 : 2000);
	117	tmp->tm_wday = bcd2bin ((wday - 1) & 0x07);
	118	tmp->tm_yday = 0;
	119	tmp->tm_isdst= 0;
	120
	121	DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
	122	tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
	123	tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
b73a19e1 YT	124
b73a19e1 YT	125	return rel;
1cb8e980 WD	126	}
	127
	128
	129	/*
	130	* Set the RTC
	131	*/
	132	void rtc_set (struct rtc_time *tmp)
	133	{
	134	DEBUGR ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
	135	tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
	136	tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
	137
	138	if (tmp->tm_year < 1970 \|\| tmp->tm_year > 2069)
	139	printf("WARNING: year should be between 1970 and 2069!\n");
8bde7f77	140
1cb8e980 WD	141	rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100));
	142	rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon));
	143	rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday + 1));
	144	rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday));
	145	rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour));
	146	rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min));
	147	rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec));
	148	}
	149
	150
	151	/*
8bde7f77 WD	152	* Reset the RTC. We setting the date back to 1970-01-01.
8bde7f77 WD	153	* We also enable the oscillator output on the SQW/OUT pin and program
1cb8e980 WD	154	* it for 32,768 Hz output. Note that according to the datasheet, turning
	155	* on the square wave output increases the current drain on the backup
	156	* battery to something between 480nA and 800nA.
	157	*/
	158	void rtc_reset (void)
	159	{
	160	struct rtc_time tmp;
	161
	162	rtc_write (RTC_SEC_REG_ADDR, 0x00); /* clearing Clock Halt */
	163	rtc_write (RTC_CTL_REG_ADDR, RTC_CTL_BIT_SQWE \| RTC_CTL_BIT_RS1 \| RTC_CTL_BIT_RS0);
	164
	165	tmp.tm_year = 1970;
	166	tmp.tm_mon = 1;
	167	tmp.tm_mday= 1;
	168	tmp.tm_hour = 0;
	169	tmp.tm_min = 0;
	170	tmp.tm_sec = 0;
	171
	172	rtc_set(&tmp);
	173
	174	printf ( "RTC: %4d-%02d-%02d %2d:%02d:%02d UTC\n",
	175	tmp.tm_year, tmp.tm_mon, tmp.tm_mday,
	176	tmp.tm_hour, tmp.tm_min, tmp.tm_sec);
	177
	178	return;
	179	}
	180
	181
	182	/*
	183	* Helper functions
	184	*/
	185
	186	static
	187	uchar rtc_read (uchar reg)
	188	{
	189	return (i2c_reg_read (CFG_I2C_RTC_ADDR, reg));
	190	}
	191
	192
	193	static void rtc_write (uchar reg, uchar val)
	194	{
	195	i2c_reg_write (CFG_I2C_RTC_ADDR, reg, val);
	196	}
	197
	198	static unsigned bcd2bin (uchar n)
	199	{
	200	return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F));
	201	}
	202
	203	static unsigned char bin2bcd (unsigned int n)
	204	{
	205	return (((n / 10) << 4) \| (n % 10));
	206	}
	207
068b60a0	208	#endif