[z180-stamp.git] / avr / pcf8583.c

/*
 * (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * Date & Time support for Philips PCF8583 RTC
 */

#include "common.h"
#include <stdlib.h>
#include "time.h"
#include "rtc.h"
#include "i2c.h"
#include "command.h"
#include "debug.h"

#define  DEBUG_RTC 0

#define debug_rtc(fmt, args...)			\
	debug_cond(DEBUG_RTC, fmt, ##args)

#define REG_CS		0x00	/* control/status */
#define REG_CSEC	0x01	/* hundredth of a second */
#define REG_SEC		0x02	/* seconds */
#define REG_MIN		0x03	/* minutes */
#define REG_HOUR	0x04	/* hours */
#define REG_YRDATE	0x05	/* year/date */
#define REG_WDMON	0x06	/* weekdays/months */
#define NR_OF_REGS	7


/* ------------------------------------------------------------------------- */

static uint_fast8_t bcd2bin(uint8_t val)
{
	return (val >> 4) * 10 + (val & 0x0f);
}

static uint8_t bin2bcd (uint_fast8_t val)
{
	div_t d = div(val, 10);

	return (d.quot << 4) | d.rem;
}


int rtc_get (struct tm *tmp)
{
	uint8_t rtcbuf[NR_OF_REGS];
	int16_t year;

	i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, rtcbuf, NR_OF_REGS);
	i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0x10, 1, (uint8_t *) &year, 2);

	debug_rtc("Get RTC year: %u, wdays/month: %02x, year/date: %02x, "
		"hour: %02x, min: %02x, sec: %02x, (stat: %02x)\n", year,
		rtcbuf[6], rtcbuf[5], rtcbuf[4], rtcbuf[3], rtcbuf[2], rtcbuf[0]);

	tmp->tm_sec  = bcd2bin (rtcbuf[REG_SEC]    & 0x7F);
	tmp->tm_min  = bcd2bin (rtcbuf[REG_MIN]    & 0x7F);
	tmp->tm_hour = bcd2bin (rtcbuf[REG_HOUR]   & 0x3F);
	tmp->tm_mday = bcd2bin (rtcbuf[REG_YRDATE] & 0x3F);
	tmp->tm_mon  = bcd2bin (rtcbuf[REG_WDMON]  & 0x1F) - 1;
	while (year%4 != (rtcbuf[REG_YRDATE]>>6)) {
		year++;
		i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0x10, 1, (uint8_t *) &year, 2);
	}
	tmp->tm_year  = year - 1900;
	tmp->tm_wday = rtcbuf[REG_WDMON] >> 5;
	tmp->tm_yday = 0;
	tmp->tm_isdst= 0;

	debug_rtc( "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 rtcbuf[REG_CS] == 0x04 ? 0 : 1;
}

int rtc_set (struct tm *tmp)
{
	uint8_t rtcbuf[NR_OF_REGS];
	int16_t year = tmp->tm_year + 1900;

	debug_rtc("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);

	rtcbuf[REG_CS] = 0x84;
	rtcbuf[REG_CSEC] = 0x00;
	rtcbuf[REG_WDMON ] = (bin2bcd(tmp->tm_mon) + 1) | ((tmp->tm_wday) << 5);
	rtcbuf[REG_YRDATE] = ((year % 4) << 6) | bin2bcd(tmp->tm_mday);
	rtcbuf[REG_HOUR  ] = bin2bcd(tmp->tm_hour);
	rtcbuf[REG_MIN   ] = bin2bcd(tmp->tm_min);
	rtcbuf[REG_SEC   ] = bin2bcd(tmp->tm_sec);

	i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0,    1, rtcbuf, NR_OF_REGS);
	i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0x10, 1, (uint8_t *) &year, 2);
	rtcbuf[REG_CS] = 0x04;
	i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, rtcbuf, 1);

	return 0;
}
Commit	Line	Data
35edb766 L	1	/*
	2	* (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
	3	*
	4	* SPDX-License-Identifier: GPL-2.0+
	5	*/
	6
61b0cfe9 L	7	/*
	8	* Date & Time support for Philips PCF8583 RTC
	9	*/
	10
61b0cfe9 L	11	#include "common.h"
61b0cfe9 L	12	#include <stdlib.h>
e63b2f75	13	#include "time.h"
61b0cfe9 L	14	#include "rtc.h"
61b0cfe9 L	15	#include "i2c.h"
e63b2f75 L	16	#include "command.h"
e63b2f75 L	17	#include "debug.h"
61b0cfe9	18
f14850db L	19	#define DEBUG_RTC 0
	20
	21	#define debug_rtc(fmt, args...) \
	22	debug_cond(DEBUG_RTC, fmt, ##args)
	23
61b0cfe9 L	24	#define REG_CS 0x00 /* control/status */
	25	#define REG_CSEC 0x01 /* hundredth of a second */
	26	#define REG_SEC 0x02 /* seconds */
	27	#define REG_MIN 0x03 /* minutes */
	28	#define REG_HOUR 0x04 /* hours */
	29	#define REG_YRDATE 0x05 /* year/date */
	30	#define REG_WDMON 0x06 /* weekdays/months */
	31	#define NR_OF_REGS 7
	32
	33
	34	/* ------------------------------------------------------------------------- */
	35
	36	static uint_fast8_t bcd2bin(uint8_t val)
	37	{
	38	return (val >> 4) * 10 + (val & 0x0f);
	39	}
	40
	41	static uint8_t bin2bcd (uint_fast8_t val)
	42	{
	43	div_t d = div(val, 10);
e63b2f75	44
61b0cfe9 L	45	return (d.quot << 4) \| d.rem;
	46	}
	47
	48
e63b2f75	49	int rtc_get (struct tm *tmp)
61b0cfe9	50	{
61b0cfe9	51	uint8_t rtcbuf[NR_OF_REGS];
e63b2f75 L	52	int16_t year;
e63b2f75 L	53
61b0cfe9 L	54	i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, rtcbuf, NR_OF_REGS);
	55	i2c_read(CONFIG_SYS_I2C_RTC_ADDR, 0x10, 1, (uint8_t *) &year, 2);
	56
85046f8c	57	debug_rtc("Get RTC year: %u, wdays/month: %02x, year/date: %02x, "
61b0cfe9 L	58	"hour: %02x, min: %02x, sec: %02x, (stat: %02x)\n", year,
	59	rtcbuf[6], rtcbuf[5], rtcbuf[4], rtcbuf[3], rtcbuf[2], rtcbuf[0]);
	60
	61	tmp->tm_sec = bcd2bin (rtcbuf[REG_SEC] & 0x7F);
	62	tmp->tm_min = bcd2bin (rtcbuf[REG_MIN] & 0x7F);
	63	tmp->tm_hour = bcd2bin (rtcbuf[REG_HOUR] & 0x3F);
	64	tmp->tm_mday = bcd2bin (rtcbuf[REG_YRDATE] & 0x3F);
e63b2f75	65	tmp->tm_mon = bcd2bin (rtcbuf[REG_WDMON] & 0x1F) - 1;
85046f8c	66	while (year%4 != (rtcbuf[REG_YRDATE]>>6)) {
61b0cfe9	67	year++;
85046f8c	68	i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0x10, 1, (uint8_t *) &year, 2);
61b0cfe9	69	}
85046f8c	70	tmp->tm_year = year - 1900;
61b0cfe9 L	71	tmp->tm_wday = rtcbuf[REG_WDMON] >> 5;
	72	tmp->tm_yday = 0;
	73	tmp->tm_isdst= 0;
	74
f14850db	75	debug_rtc( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
61b0cfe9 L	76	tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
	77	tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
	78
85046f8c	79	return rtcbuf[REG_CS] == 0x04 ? 0 : 1;
61b0cfe9 L	80	}
61b0cfe9 L	81
e63b2f75	82	int rtc_set (struct tm *tmp)
61b0cfe9 L	83	{
61b0cfe9 L	84	uint8_t rtcbuf[NR_OF_REGS];
85046f8c	85	int16_t year = tmp->tm_year + 1900;
61b0cfe9	86
f14850db	87	debug_rtc("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
61b0cfe9 L	88	tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
	89	tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
	90
	91	rtcbuf[REG_CS] = 0x84;
	92	rtcbuf[REG_CSEC] = 0x00;
e63b2f75	93	rtcbuf[REG_WDMON ] = (bin2bcd(tmp->tm_mon) + 1) \| ((tmp->tm_wday) << 5);
85046f8c	94	rtcbuf[REG_YRDATE] = ((year % 4) << 6) \| bin2bcd(tmp->tm_mday);
61b0cfe9 L	95	rtcbuf[REG_HOUR ] = bin2bcd(tmp->tm_hour);
	96	rtcbuf[REG_MIN ] = bin2bcd(tmp->tm_min);
	97	rtcbuf[REG_SEC ] = bin2bcd(tmp->tm_sec);
	98
	99	i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, rtcbuf, NR_OF_REGS);
85046f8c	100	i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0x10, 1, (uint8_t *) &year, 2);
61b0cfe9 L	101	rtcbuf[REG_CS] = 0x04;
	102	i2c_write(CONFIG_SYS_I2C_RTC_ADDR, 0, 1, rtcbuf, 1);
	103
61b0cfe9 L	104	return 0;
61b0cfe9 L	105	}