/* * ds1302.c - Support for the Dallas Semiconductor DS1302 Timekeeping Chip * * Rex G. Feany <rfeany@zumanetworks.com> * */#include <common.h>#include <command.h>#include <rtc.h>#if defined(CONFIG_RTC_DS1302) && (CONFIG_COMMANDS & CFG_CMD_DATE)/* GPP Pins */#define DATA		0x200#define SCLK		0x400#define RST		0x800/* Happy Fun Defines(tm) */#define RESET		rtc_go_low(RST), rtc_go_low(SCLK)#define N_RESET		rtc_go_high(RST), rtc_go_low(SCLK)#define CLOCK_HIGH	rtc_go_high(SCLK)#define CLOCK_LOW	rtc_go_low(SCLK)#define DATA_HIGH	rtc_go_high(DATA)#define DATA_LOW	rtc_go_low(DATA)#define DATA_READ	(GTREGREAD(GPP_VALUE) & DATA)#undef RTC_DEBUG#ifdef RTC_DEBUG#  define DPRINTF(x,args...)	printf("ds1302: " x , ##args)static inline void DUMP(const char *ptr, int num){	while (num--) printf("%x ", *ptr++);	printf("]\n");}#else#  define DPRINTF(x,args...)#  define DUMP(ptr, num)#endif/* time data format for DS1302 */struct ds1302_st{	unsigned char CH:1;		/* clock halt 1=stop 0=start */	unsigned char sec10:3;	unsigned char sec:4;	unsigned char zero0:1;	unsigned char min10:3;	unsigned char min:4;	unsigned char fmt:1;		/* 1=12 hour 0=24 hour */	unsigned char zero1:1;	unsigned char hr10:2;	/* 10 (0-2) or am/pm (am/pm, 0-1) */	unsigned char hr:4;	unsigned char zero2:2;	unsigned char date10:2;	unsigned char date:4;	unsigned char zero3:3;	unsigned char month10:1;	unsigned char month:4;	unsigned char zero4:5;	unsigned char day:3; 		/* day of week */	unsigned char year10:4;	unsigned char year:4;	unsigned char WP:1;		/* write protect 1=protect 0=unprot */	unsigned char zero5:7;};static int ds1302_initted=0;/* Pin control */static inline voidrtc_go_high(unsigned int mask){	unsigned int f = GTREGREAD(GPP_VALUE) | mask;	GT_REG_WRITE(GPP_VALUE, f);}static inline voidrtc_go_low(unsigned int mask){	unsigned int f = GTREGREAD(GPP_VALUE) & ~mask;	GT_REG_WRITE(GPP_VALUE, f);}static inline voidrtc_go_input(unsigned int mask){	unsigned int f = GTREGREAD(GPP_IO_CONTROL) & ~mask;	GT_REG_WRITE(GPP_IO_CONTROL, f);}static inline voidrtc_go_output(unsigned int mask){	unsigned int f = GTREGREAD(GPP_IO_CONTROL) | mask;	GT_REG_WRITE(GPP_IO_CONTROL, f);}/* Access data in RTC */static voidwrite_byte(unsigned char b){	int i;	unsigned char mask=1;	for(i=0;i<8;i++) {		CLOCK_LOW;			/* Lower clock */		(b&mask)?DATA_HIGH:DATA_LOW;	/* set data */		udelay(1);		CLOCK_HIGH;		/* latch data with rising clock */		udelay(1);		mask=mask<<1;	}}static unsigned charread_byte(void){	int i;	unsigned char mask=1;	unsigned char b=0;	for(i=0;i<8;i++) {		CLOCK_LOW;		udelay(1);		if (DATA_READ) b|=mask;	/* if this bit is high, set in b */		CLOCK_HIGH;		/* clock out next bit */		udelay(1);		mask=mask<<1;	}	return b;}static voidread_ser_drv(unsigned char addr, unsigned char *buf, int count){	int i;#ifdef RTC_DEBUG	char *foo = buf;#endif	DPRINTF("READ 0x%x bytes @ 0x%x [ ", count, addr);	addr|=1;	/* READ */	N_RESET;	udelay(4);	write_byte(addr);	rtc_go_input(DATA); /* Put gpp pin into input mode */	udelay(1);	for(i=0;i<count;i++) *(buf++)=read_byte();	RESET;	rtc_go_output(DATA);/* Reset gpp for output */	udelay(4);	DUMP(foo, count);}static voidwrite_ser_drv(unsigned char addr, unsigned char *buf, int count){	int i;	DPRINTF("WRITE 0x%x bytes @ 0x%x [ ", count, addr);	DUMP(buf, count);	addr&=~1;	/* WRITE */	N_RESET;	udelay(4);	write_byte(addr);	for(i=0;i<count;i++) write_byte(*(buf++));	RESET;	udelay(4);}voidrtc_init(void){    	struct ds1302_st bbclk;	unsigned char b;	int mod;	DPRINTF("init\n");	rtc_go_output(DATA|SCLK|RST);	/* disable write protect */	b = 0;	write_ser_drv(0x8e,&b,1);	/* enable trickle */	b = 0xa5;	/* 1010.0101 */	write_ser_drv(0x90,&b,1);	/* read burst */	read_ser_drv(0xbe, (unsigned char *)&bbclk, 8);	/* Sanity checks */	mod = 0;	if (bbclk.CH) {		printf("ds1302: Clock was halted, starting clock\n");		bbclk.CH=0;		mod=1;	}	if (bbclk.fmt) {		printf("ds1302: Clock was in 12 hour mode, fixing\n");		bbclk.fmt=0;		mod=1;	}	if (bbclk.year>9) {		printf("ds1302: Year was corrupted, fixing\n");		bbclk.year10=100/10;	/* 2000 - why not? ;) */		bbclk.year=0;		mod=1;	}	/* Write out the changes if needed */	if (mod) {		/* enable write protect */		bbclk.WP = 1;		write_ser_drv(0xbe,(unsigned char *)&bbclk,8);	} else {		/* Else just turn write protect on */		b = 0x80;		write_ser_drv(0x8e,&b,1);	}	DPRINTF("init done\n");	ds1302_initted=1;}voidrtc_reset(void){	if(!ds1302_initted) rtc_init();	/* TODO */}voidrtc_get(struct rtc_time *tmp){	struct ds1302_st bbclk;	if(!ds1302_initted) rtc_init();	read_ser_drv(0xbe,(unsigned char *)&bbclk, 8);      /* read burst */	if (bbclk.CH) {		printf("ds1302: rtc_get: Clock was halted, clock probably "			"corrupt\n");	}	tmp->tm_sec=10*bbclk.sec10+bbclk.sec;	tmp->tm_min=10*bbclk.min10+bbclk.min;	tmp->tm_hour=10*bbclk.hr10+bbclk.hr;	tmp->tm_wday=bbclk.day;	tmp->tm_mday=10*bbclk.date10+bbclk.date;	tmp->tm_mon=10*bbclk.month10+bbclk.month;	tmp->tm_year=10*bbclk.year10+bbclk.year + 1900;	tmp->tm_yday = 0;	tmp->tm_isdst= 0;	DPRINTF("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 );}voidrtc_set(struct rtc_time *tmp){	struct ds1302_st bbclk;	unsigned char b=0;	if(!ds1302_initted) rtc_init();	DPRINTF("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);	memset(&bbclk,0,sizeof(bbclk));	bbclk.CH=0; /* dont halt */	bbclk.WP=1; /* write protect when we're done */	bbclk.sec10=tmp->tm_sec/10;	bbclk.sec=tmp->tm_sec%10;	bbclk.min10=tmp->tm_min/10;	bbclk.min=tmp->tm_min%10;	bbclk.hr10=tmp->tm_hour/10;	bbclk.hr=tmp->tm_hour%10;	bbclk.day=tmp->tm_wday;	bbclk.date10=tmp->tm_mday/10;	bbclk.date=tmp->tm_mday%10;	bbclk.month10=tmp->tm_mon/10;	bbclk.month=tmp->tm_mon%10;	tmp->tm_year -= 1900;	bbclk.year10=tmp->tm_year/10;	bbclk.year=tmp->tm_year%10;	write_ser_drv(0x8e,&b,1);           /* disable write protect */	write_ser_drv(0xbe,(unsigned char *)&bbclk, 8);     /* write burst */}#endif