[people/ms/u-boot.git] / drivers / rtc / ds1337.c

/*
 * (C) Copyright 2001, 2002
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 * Keith Outwater, keith_outwater@mvis.com`
 *
 * 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)
 * DS1337 Real Time Clock (RTC).
 */

#include <common.h>
#include <command.h>
#include <rtc.h>
#include <i2c.h>

#if defined(CONFIG_RTC_DS1337) && defined(CONFIG_CMD_DATE)

/*---------------------------------------------------------------------*/
#undef DEBUG_RTC

#ifdef DEBUG_RTC
#define DEBUGR(fmt,args...) printf(fmt ,##args)
#else
#define DEBUGR(fmt,args...)
#endif
/*---------------------------------------------------------------------*/

/*
 * RTC register addresses
 */
#define RTC_SEC_REG_ADDR	0x0
#define RTC_MIN_REG_ADDR	0x1
#define RTC_HR_REG_ADDR		0x2
#define RTC_DAY_REG_ADDR	0x3
#define RTC_DATE_REG_ADDR	0x4
#define RTC_MON_REG_ADDR	0x5
#define RTC_YR_REG_ADDR		0x6
#define RTC_CTL_REG_ADDR	0x0e
#define RTC_STAT_REG_ADDR	0x0f

/*
 * RTC control register bits
 */
#define RTC_CTL_BIT_A1IE	0x1	/* Alarm 1 interrupt enable     */
#define RTC_CTL_BIT_A2IE	0x2	/* Alarm 2 interrupt enable     */
#define RTC_CTL_BIT_INTCN	0x4	/* Interrupt control            */
#define RTC_CTL_BIT_RS1		0x8	/* Rate select 1                */
#define RTC_CTL_BIT_RS2		0x10	/* Rate select 2                */
#define RTC_CTL_BIT_DOSC	0x80	/* Disable Oscillator           */

/*
 * RTC status register bits
 */
#define RTC_STAT_BIT_A1F	0x1	/* Alarm 1 flag                 */
#define RTC_STAT_BIT_A2F	0x2	/* Alarm 2 flag                 */
#define RTC_STAT_BIT_OSF	0x80	/* Oscillator stop flag         */


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_cent, year, control, status;

	control = rtc_read (RTC_CTL_REG_ADDR);
	status = rtc_read (RTC_STAT_REG_ADDR);
	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_cent = rtc_read (RTC_MON_REG_ADDR);
	year = rtc_read (RTC_YR_REG_ADDR);

	DEBUGR ("Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
		"hr: %02x min: %02x sec: %02x control: %02x status: %02x\n",
		year, mon_cent, mday, wday, hour, min, sec, control, status);

	if (status & RTC_STAT_BIT_OSF) {
		printf ("### Warning: RTC oscillator has stopped\n");
		/* clear the OSF flag */
		rtc_write (RTC_STAT_REG_ADDR,
			   rtc_read (RTC_STAT_REG_ADDR) & ~RTC_STAT_BIT_OSF);
	}

	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_cent & 0x1F);
	tmp->tm_year = bcd2bin (year) + ((mon_cent & 0x80) ? 2000 : 1900);
	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)
{
	uchar century;

	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);

	rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100));

	century = (tmp->tm_year >= 2000) ? 0x80 : 0;
	rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon) | century);

	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 also enable the oscillator output on the
 * SQW/INTB* 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 from about
 * 600 nA to 2uA.
 */
void rtc_reset (void)
{
	rtc_write (RTC_CTL_REG_ADDR, RTC_CTL_BIT_RS1 | RTC_CTL_BIT_RS2);
}


/*
 * 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
5d3207da WD	1	/*
	2	* (C) Copyright 2001, 2002
	3	* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
	4	* Keith Outwater, keith_outwater@mvis.com`
	5	*
	6	* See file CREDITS for list of people who contributed to this
	7	* project.
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License as
	11	* published by the Free Software Foundation; either version 2 of
	12	* the License, or (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to the Free Software
	21	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	22	* MA 02111-1307 USA
	23	*/
	24
	25	/*
	26	* Date & Time support (no alarms) for Dallas Semiconductor (now Maxim)
	27	* DS1337 Real Time Clock (RTC).
	28	*/
	29
	30	#include <common.h>
	31	#include <command.h>
	32	#include <rtc.h>
	33	#include <i2c.h>
	34
a593814f	35	#if defined(CONFIG_RTC_DS1337) && defined(CONFIG_CMD_DATE)
5d3207da WD	36
	37	/---------------------------------------------------------------------/
	38	#undef DEBUG_RTC
	39
	40	#ifdef DEBUG_RTC
	41	#define DEBUGR(fmt,args...) printf(fmt ,##args)
	42	#else
	43	#define DEBUGR(fmt,args...)
	44	#endif
	45	/---------------------------------------------------------------------/
	46
	47	/*
	48	* RTC register addresses
	49	*/
	50	#define RTC_SEC_REG_ADDR 0x0
	51	#define RTC_MIN_REG_ADDR 0x1
	52	#define RTC_HR_REG_ADDR 0x2
	53	#define RTC_DAY_REG_ADDR 0x3
	54	#define RTC_DATE_REG_ADDR 0x4
	55	#define RTC_MON_REG_ADDR 0x5
	56	#define RTC_YR_REG_ADDR 0x6
	57	#define RTC_CTL_REG_ADDR 0x0e
	58	#define RTC_STAT_REG_ADDR 0x0f
	59
	60	/*
	61	* RTC control register bits
	62	*/
	63	#define RTC_CTL_BIT_A1IE 0x1 /* Alarm 1 interrupt enable */
	64	#define RTC_CTL_BIT_A2IE 0x2 /* Alarm 2 interrupt enable */
	65	#define RTC_CTL_BIT_INTCN 0x4 /* Interrupt control */
	66	#define RTC_CTL_BIT_RS1 0x8 /* Rate select 1 */
	67	#define RTC_CTL_BIT_RS2 0x10 /* Rate select 2 */
	68	#define RTC_CTL_BIT_DOSC 0x80 /* Disable Oscillator */
	69
	70	/*
	71	* RTC status register bits
	72	*/
	73	#define RTC_STAT_BIT_A1F 0x1 /* Alarm 1 flag */
	74	#define RTC_STAT_BIT_A2F 0x2 /* Alarm 2 flag */
	75	#define RTC_STAT_BIT_OSF 0x80 /* Oscillator stop flag */
	76
	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	/*
	85	* Get the current time from the RTC
	86	*/
	87	void rtc_get (struct rtc_time *tmp)
	88	{
	89	uchar sec, min, hour, mday, wday, mon_cent, year, control, status;
	90
	91	control = rtc_read (RTC_CTL_REG_ADDR);
	92	status = rtc_read (RTC_STAT_REG_ADDR);
	93	sec = rtc_read (RTC_SEC_REG_ADDR);
	94	min = rtc_read (RTC_MIN_REG_ADDR);
	95	hour = rtc_read (RTC_HR_REG_ADDR);
	96	wday = rtc_read (RTC_DAY_REG_ADDR);
	97	mday = rtc_read (RTC_DATE_REG_ADDR);
	98	mon_cent = rtc_read (RTC_MON_REG_ADDR);
	99	year = rtc_read (RTC_YR_REG_ADDR);
100
101	DEBUGR ("Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
102	"hr: %02x min: %02x sec: %02x control: %02x status: %02x\n",
103	year, mon_cent, mday, wday, hour, min, sec, control, status);
104
105	if (status & RTC_STAT_BIT_OSF) {
106	printf ("### Warning: RTC oscillator has stopped\n");
107	/* clear the OSF flag */
108	rtc_write (RTC_STAT_REG_ADDR,
109	rtc_read (RTC_STAT_REG_ADDR) & ~RTC_STAT_BIT_OSF);
110	}
111
112	tmp->tm_sec = bcd2bin (sec & 0x7F);
113	tmp->tm_min = bcd2bin (min & 0x7F);
114	tmp->tm_hour = bcd2bin (hour & 0x3F);
115	tmp->tm_mday = bcd2bin (mday & 0x3F);
116	tmp->tm_mon = bcd2bin (mon_cent & 0x1F);
117	tmp->tm_year = bcd2bin (year) + ((mon_cent & 0x80) ? 2000 : 1900);
118	tmp->tm_wday = bcd2bin ((wday - 1) & 0x07);
119	tmp->tm_yday = 0;
120	tmp->tm_isdst= 0;
121
122	DEBUGR ("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
123	tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
124	tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
125	}
126
127
128	/*
129	* Set the RTC
130	*/
131	void rtc_set (struct rtc_time *tmp)
132	{
133	uchar century;
134
135	DEBUGR ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
136	tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
137	tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
138
139	rtc_write (RTC_YR_REG_ADDR, bin2bcd (tmp->tm_year % 100));
140
141	century = (tmp->tm_year >= 2000) ? 0x80 : 0;
142	rtc_write (RTC_MON_REG_ADDR, bin2bcd (tmp->tm_mon) \| century);
143
144	rtc_write (RTC_DAY_REG_ADDR, bin2bcd (tmp->tm_wday + 1));
145	rtc_write (RTC_DATE_REG_ADDR, bin2bcd (tmp->tm_mday));
146	rtc_write (RTC_HR_REG_ADDR, bin2bcd (tmp->tm_hour));
147	rtc_write (RTC_MIN_REG_ADDR, bin2bcd (tmp->tm_min));
148	rtc_write (RTC_SEC_REG_ADDR, bin2bcd (tmp->tm_sec));
149	}
150
151
152	/*
153	* Reset the RTC. We also enable the oscillator output on the
154	* SQW/INTB* pin and program it for 32,768 Hz output. Note that
155	* according to the datasheet, turning on the square wave output
156	* increases the current drain on the backup battery from about
157	* 600 nA to 2uA.
158	*/
159	void rtc_reset (void)
160	{
161	rtc_write (RTC_CTL_REG_ADDR, RTC_CTL_BIT_RS1 \| RTC_CTL_BIT_RS2);
162	}
163
164
165	/*
166	* Helper functions
167	*/
168
169	static
170	uchar rtc_read (uchar reg)
171	{
172	return (i2c_reg_read (CFG_I2C_RTC_ADDR, reg));
173	}
174
175
176	static void rtc_write (uchar reg, uchar val)
177	{
178	i2c_reg_write (CFG_I2C_RTC_ADDR, reg, val);
179	}
180
181	static unsigned bcd2bin (uchar n)
182	{
183	return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F));
184	}
185
186	static unsigned char bin2bcd (unsigned int n)
187	{
188	return (((n / 10) << 4) \| (n % 10));
189	}
190
068b60a0	191	#endif