[net-next-2.6.git] / arch / cris / arch-v10 / drivers / ds1302.c

/*!***************************************************************************
*!
*! FILE NAME  : ds1302.c
*!
*! DESCRIPTION: Implements an interface for the DS1302 RTC through Etrax I/O
*!
*! Functions exported: ds1302_readreg, ds1302_writereg, ds1302_init
*!
*! ---------------------------------------------------------------------------
*!
*! (C) Copyright 1999-2007 Axis Communications AB, LUND, SWEDEN
*!
*!***************************************************************************/


#include <linux/fs.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/miscdevice.h>
#include <linux/delay.h>
#include <linux/bcd.h>
#include <linux/capability.h>

#include <asm/uaccess.h>
#include <asm/system.h>
#include <arch/svinto.h>
#include <asm/io.h>
#include <asm/rtc.h>
#include <arch/io_interface_mux.h>

#include "i2c.h"

#define RTC_MAJOR_NR 121 /* local major, change later */

static const char ds1302_name[] = "ds1302";

/* The DS1302 might be connected to different bits on different products. 
 * It has three signals - SDA, SCL and RST. RST and SCL are always outputs,
 * but SDA can have a selected direction.
 * For now, only PORT_PB is hardcoded.
 */

/* The RST bit may be on either the Generic Port or Port PB. */
#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
#define TK_RST_OUT(x) REG_SHADOW_SET(R_PORT_G_DATA,  port_g_data_shadow,  CONFIG_ETRAX_DS1302_RSTBIT, x)
#define TK_RST_DIR(x)
#else
#define TK_RST_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_RSTBIT, x)
#define TK_RST_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR,  port_pb_dir_shadow,  CONFIG_ETRAX_DS1302_RSTBIT, x)
#endif


#define TK_SDA_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_SDABIT, x)
#define TK_SCL_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_SCLBIT, x)

#define TK_SDA_IN()   ((*R_PORT_PB_READ >> CONFIG_ETRAX_DS1302_SDABIT) & 1)
/* 1 is out, 0 is in */
#define TK_SDA_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR,  port_pb_dir_shadow,  CONFIG_ETRAX_DS1302_SDABIT, x)
#define TK_SCL_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR,  port_pb_dir_shadow,  CONFIG_ETRAX_DS1302_SCLBIT, x)


/*
 * The reason for tempudelay and not udelay is that loops_per_usec
 * (used in udelay) is not set when functions here are called from time.c 
 */

static void tempudelay(int usecs) 
{
	volatile int loops;

	for(loops = usecs * 12; loops > 0; loops--)
		/* nothing */;	
}


/* Send 8 bits. */
static void
out_byte(unsigned char x) 
{
	int i;
	TK_SDA_DIR(1);
	for (i = 8; i--;) {
		/* The chip latches incoming bits on the rising edge of SCL. */
		TK_SCL_OUT(0);
		TK_SDA_OUT(x & 1);
		tempudelay(1);
		TK_SCL_OUT(1);
		tempudelay(1);
		x >>= 1;
	}
	TK_SDA_DIR(0);
}

static unsigned char
in_byte(void) 
{
	unsigned char x = 0;
	int i;

	/* Read byte. Bits come LSB first, on the falling edge of SCL.
	 * Assume SDA is in input direction already.
	 */
	TK_SDA_DIR(0);

	for (i = 8; i--;) {
		TK_SCL_OUT(0);
		tempudelay(1);
		x >>= 1;
		x |= (TK_SDA_IN() << 7);
		TK_SCL_OUT(1);
		tempudelay(1);
	}

	return x;
}

/* Prepares for a transaction by de-activating RST (active-low). */

static void
start(void) 
{
	TK_SCL_OUT(0);
	tempudelay(1);
	TK_RST_OUT(0);
	tempudelay(5);
	TK_RST_OUT(1);	
}

/* Ends a transaction by taking RST active again. */

static void
stop(void) 
{
	tempudelay(2);
	TK_RST_OUT(0);
}

/* Enable writing. */

static void
ds1302_wenable(void) 
{
	start(); 	
	out_byte(0x8e); /* Write control register  */
	out_byte(0x00); /* Disable write protect bit 7 = 0 */
	stop();
}

/* Disable writing. */

static void
ds1302_wdisable(void) 
{
	start();
	out_byte(0x8e); /* Write control register  */
	out_byte(0x80); /* Disable write protect bit 7 = 0 */
	stop();
}


/* Read a byte from the selected register in the DS1302. */

unsigned char
ds1302_readreg(int reg) 
{
	unsigned char x;

	start();
	out_byte(0x81 | (reg << 1)); /* read register */
	x = in_byte();
	stop();

	return x;
}

/* Write a byte to the selected register. */

void
ds1302_writereg(int reg, unsigned char val) 
{
#ifndef CONFIG_ETRAX_RTC_READONLY
	int do_writereg = 1;
#else
	int do_writereg = 0;

	if (reg == RTC_TRICKLECHARGER)
		do_writereg = 1;
#endif

	if (do_writereg) {
		ds1302_wenable();
		start();
		out_byte(0x80 | (reg << 1)); /* write register */
		out_byte(val);
		stop();
		ds1302_wdisable();
	}
}

void
get_rtc_time(struct rtc_time *rtc_tm) 
{
	unsigned long flags;

	local_irq_save(flags);

	rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS);
	rtc_tm->tm_min = CMOS_READ(RTC_MINUTES);
	rtc_tm->tm_hour = CMOS_READ(RTC_HOURS);
	rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
	rtc_tm->tm_mon = CMOS_READ(RTC_MONTH);
	rtc_tm->tm_year = CMOS_READ(RTC_YEAR);

	local_irq_restore(flags);
	
	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);

	/*
	 * Account for differences between how the RTC uses the values
	 * and how they are defined in a struct rtc_time;
	 */

	if (rtc_tm->tm_year <= 69)
		rtc_tm->tm_year += 100;

	rtc_tm->tm_mon--;
}

static unsigned char days_in_mo[] = 
    {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

/* ioctl that supports RTC_RD_TIME and RTC_SET_TIME (read and set time/date). */

static int
rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
	  unsigned long arg) 
{
	unsigned long flags;

	switch(cmd) {
		case RTC_RD_TIME:	/* read the time/date from RTC	*/
		{
			struct rtc_time rtc_tm;
						
			memset(&rtc_tm, 0, sizeof (struct rtc_time));
			get_rtc_time(&rtc_tm);						
			if (copy_to_user((struct rtc_time*)arg, &rtc_tm, sizeof(struct rtc_time)))
				return -EFAULT;	
			return 0;
		}

		case RTC_SET_TIME:	/* set the RTC */
		{
			struct rtc_time rtc_tm;
			unsigned char mon, day, hrs, min, sec, leap_yr;
			unsigned int yrs;

			if (!capable(CAP_SYS_TIME))
				return -EPERM;

			if (copy_from_user(&rtc_tm, (struct rtc_time*)arg, sizeof(struct rtc_time)))
				return -EFAULT;

			yrs = rtc_tm.tm_year + 1900;
			mon = rtc_tm.tm_mon + 1;   /* tm_mon starts at zero */
			day = rtc_tm.tm_mday;
			hrs = rtc_tm.tm_hour;
			min = rtc_tm.tm_min;
			sec = rtc_tm.tm_sec;
			
			
			if ((yrs < 1970) || (yrs > 2069))
				return -EINVAL;

			leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));

			if ((mon > 12) || (day == 0))
				return -EINVAL;

			if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
				return -EINVAL;
			
			if ((hrs >= 24) || (min >= 60) || (sec >= 60))
				return -EINVAL;

			if (yrs >= 2000)
				yrs -= 2000;	/* RTC (0, 1, ... 69) */
			else
				yrs -= 1900;	/* RTC (70, 71, ... 99) */

			sec = bin2bcd(sec);
			min = bin2bcd(min);
			hrs = bin2bcd(hrs);
			day = bin2bcd(day);
			mon = bin2bcd(mon);
			yrs = bin2bcd(yrs);

			local_irq_save(flags);
			CMOS_WRITE(yrs, RTC_YEAR);
			CMOS_WRITE(mon, RTC_MONTH);
			CMOS_WRITE(day, RTC_DAY_OF_MONTH);
			CMOS_WRITE(hrs, RTC_HOURS);
			CMOS_WRITE(min, RTC_MINUTES);
			CMOS_WRITE(sec, RTC_SECONDS);
			local_irq_restore(flags);

			/* Notice that at this point, the RTC is updated but
			 * the kernel is still running with the old time.
			 * You need to set that separately with settimeofday
			 * or adjtimex.
			 */
			return 0;
		}

		case RTC_SET_CHARGE: /* set the RTC TRICKLE CHARGE register */
		{
			int tcs_val;

			if (!capable(CAP_SYS_TIME))
				return -EPERM;
			
			if(copy_from_user(&tcs_val, (int*)arg, sizeof(int)))
				return -EFAULT;

			tcs_val = RTC_TCR_PATTERN | (tcs_val & 0x0F);
			ds1302_writereg(RTC_TRICKLECHARGER, tcs_val);
			return 0;
		}
		case RTC_VL_READ:
		{
			/* TODO:
			 * Implement voltage low detection support
			 */
			printk(KERN_WARNING "DS1302: RTC Voltage Low detection"
			       " is not supported\n");
			return 0;
		}
		case RTC_VL_CLR:
		{
			/* TODO:
			 * Nothing to do since Voltage Low detection is not supported
			 */
			return 0;
		}
		default:
			return -ENOIOCTLCMD;
	}
}

static void
print_rtc_status(void)
{
	struct rtc_time tm;

	get_rtc_time(&tm);

	/*
	 * There is no way to tell if the luser has the RTC set for local
	 * time or for Universal Standard Time (GMT). Probably local though.
	 */

	printk(KERN_INFO "rtc_time\t: %02d:%02d:%02d\n",
	       tm.tm_hour, tm.tm_min, tm.tm_sec);
	printk(KERN_INFO "rtc_date\t: %04d-%02d-%02d\n",
	       tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
}

/* The various file operations we support. */

static const struct file_operations rtc_fops = {
	.owner =	THIS_MODULE,
	.ioctl =	rtc_ioctl,
}; 

/* Probe for the chip by writing something to its RAM and try reading it back. */

#define MAGIC_PATTERN 0x42

static int __init
ds1302_probe(void) 
{
	int retval, res; 

	TK_RST_DIR(1);
	TK_SCL_DIR(1);
	TK_SDA_DIR(0);
	
	/* Try to talk to timekeeper. */

	ds1302_wenable();  
	start();
	out_byte(0xc0); /* write RAM byte 0 */	
	out_byte(MAGIC_PATTERN); /* write something magic */
	start();
	out_byte(0xc1); /* read RAM byte 0 */

	if((res = in_byte()) == MAGIC_PATTERN) {
		stop();
		ds1302_wdisable();
		printk(KERN_INFO "%s: RTC found.\n", ds1302_name);
		printk(KERN_INFO "%s: SDA, SCL, RST on PB%i, PB%i, %s%i\n",
		       ds1302_name,
		       CONFIG_ETRAX_DS1302_SDABIT,
		       CONFIG_ETRAX_DS1302_SCLBIT,
#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
		       "GENIO",
#else
		       "PB",
#endif
		       CONFIG_ETRAX_DS1302_RSTBIT);
		       print_rtc_status();
		retval = 1;
	} else {
		stop();
		retval = 0;
	}

	return retval;
}


/* Just probe for the RTC and register the device to handle the ioctl needed. */

int __init
ds1302_init(void) 
{
#ifdef CONFIG_ETRAX_I2C
	i2c_init();
#endif

	if (!ds1302_probe()) {
#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
#if CONFIG_ETRAX_DS1302_RSTBIT == 27
		/*
		 * The only way to set g27 to output is to enable ATA.
		 *
		 * Make sure that R_GEN_CONFIG is setup correct.
		 */
		/* Allocating the ATA interface will grab almost all
		 * pins in I/O groups a, b, c and d.  A consequence of
		 * allocating the ATA interface is that the fixed
		 * interfaces shared RAM, parallel port 0, parallel
		 * port 1, parallel port W, SCSI-8 port 0, SCSI-8 port
		 * 1, SCSI-W, serial port 2, serial port 3,
		 * synchronous serial port 3 and USB port 2 and almost
		 * all GPIO pins on port g cannot be used.
		 */
		if (cris_request_io_interface(if_ata, "ds1302/ATA")) {
			printk(KERN_WARNING "ds1302: Failed to get IO interface\n");
			return -1;
		}

#elif CONFIG_ETRAX_DS1302_RSTBIT == 0
		if (cris_io_interface_allocate_pins(if_gpio_grp_a,
						    'g',
						    CONFIG_ETRAX_DS1302_RSTBIT,
						    CONFIG_ETRAX_DS1302_RSTBIT)) {
			printk(KERN_WARNING "ds1302: Failed to get IO interface\n");
			return -1;
		}

		/* Set the direction of this bit to out. */
		genconfig_shadow = ((genconfig_shadow &
 				     ~IO_MASK(R_GEN_CONFIG, g0dir)) |
 				   (IO_STATE(R_GEN_CONFIG, g0dir, out)));
		*R_GEN_CONFIG = genconfig_shadow;
#endif
		if (!ds1302_probe()) {
			printk(KERN_WARNING "%s: RTC not found.\n", ds1302_name);
			return -1;
		}
#else
		printk(KERN_WARNING "%s: RTC not found.\n", ds1302_name);
		return -1;
#endif
  	}
	/* Initialise trickle charger */
	ds1302_writereg(RTC_TRICKLECHARGER,
			RTC_TCR_PATTERN |(CONFIG_ETRAX_DS1302_TRICKLE_CHARGE & 0x0F));
        /* Start clock by resetting CLOCK_HALT */
	ds1302_writereg(RTC_SECONDS, (ds1302_readreg(RTC_SECONDS) & 0x7F));
	return 0;
}

static int __init ds1302_register(void)
{
	ds1302_init();
	if (register_chrdev(RTC_MAJOR_NR, ds1302_name, &rtc_fops)) {
		printk(KERN_INFO "%s: unable to get major %d for rtc\n", 
		       ds1302_name, RTC_MAJOR_NR);
		return -1;
	}
        return 0;

}

module_init(ds1302_register);
Commit	Line	Data
1da177e4 LT	1	/!**************************************************************************
	2	*!
	3	*! FILE NAME : ds1302.c
	4	*!
	5	*! DESCRIPTION: Implements an interface for the DS1302 RTC through Etrax I/O
	6	*!
	7	*! Functions exported: ds1302_readreg, ds1302_writereg, ds1302_init
	8	*!
1da177e4 LT	9	*! ---------------------------------------------------------------------------
1da177e4 LT	10	*!
bbde25b1	11	*! (C) Copyright 1999-2007 Axis Communications AB, LUND, SWEDEN
1da177e4 LT	12	*!
	13	!**************************************************************************/
	14
1da177e4 LT	15
	16	#include <linux/fs.h>
	17	#include <linux/init.h>
	18	#include <linux/mm.h>
	19	#include <linux/module.h>
	20	#include <linux/miscdevice.h>
	21	#include <linux/delay.h>
	22	#include <linux/bcd.h>
a9415644	23	#include <linux/capability.h>
1da177e4 LT	24
	25	#include <asm/uaccess.h>
	26	#include <asm/system.h>
556dcee7	27	#include <arch/svinto.h>
1da177e4 LT	28	#include <asm/io.h>
1da177e4 LT	29	#include <asm/rtc.h>
556dcee7	30	#include <arch/io_interface_mux.h>
1da177e4	31
bbde25b1 JN	32	#include "i2c.h"
bbde25b1 JN	33
1da177e4 LT	34	#define RTC_MAJOR_NR 121 /* local major, change later */
	35
	36	static const char ds1302_name[] = "ds1302";
	37
	38	/* The DS1302 might be connected to different bits on different products.
	39	* It has three signals - SDA, SCL and RST. RST and SCL are always outputs,
	40	* but SDA can have a selected direction.
	41	* For now, only PORT_PB is hardcoded.
	42	*/
	43
	44	/* The RST bit may be on either the Generic Port or Port PB. */
	45	#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
	46	#define TK_RST_OUT(x) REG_SHADOW_SET(R_PORT_G_DATA, port_g_data_shadow, CONFIG_ETRAX_DS1302_RSTBIT, x)
	47	#define TK_RST_DIR(x)
	48	#else
	49	#define TK_RST_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_RSTBIT, x)
	50	#define TK_RST_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, CONFIG_ETRAX_DS1302_RSTBIT, x)
	51	#endif
	52
	53
	54	#define TK_SDA_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_SDABIT, x)
	55	#define TK_SCL_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_SCLBIT, x)
	56
	57	#define TK_SDA_IN() ((*R_PORT_PB_READ >> CONFIG_ETRAX_DS1302_SDABIT) & 1)
	58	/* 1 is out, 0 is in */
	59	#define TK_SDA_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, CONFIG_ETRAX_DS1302_SDABIT, x)
	60	#define TK_SCL_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, CONFIG_ETRAX_DS1302_SCLBIT, x)
	61
	62
	63	/*
	64	* The reason for tempudelay and not udelay is that loops_per_usec
	65	* (used in udelay) is not set when functions here are called from time.c
	66	*/
	67
	68	static void tempudelay(int usecs)
	69	{
	70	volatile int loops;
	71
	72	for(loops = usecs * 12; loops > 0; loops--)
	73	/* nothing */;
	74	}
	75
	76
	77	/* Send 8 bits. */
	78	static void
	79	out_byte(unsigned char x)
	80	{
	81	int i;
	82	TK_SDA_DIR(1);
	83	for (i = 8; i--;) {
	84	/* The chip latches incoming bits on the rising edge of SCL. */
	85	TK_SCL_OUT(0);
	86	TK_SDA_OUT(x & 1);
	87	tempudelay(1);
	88	TK_SCL_OUT(1);
	89	tempudelay(1);
	90	x >>= 1;
	91	}
	92	TK_SDA_DIR(0);
	93	}
	94
	95	static unsigned char
	96	in_byte(void)
	97	{
98	unsigned char x = 0;
99	int i;
100
101	/* Read byte. Bits come LSB first, on the falling edge of SCL.
102	* Assume SDA is in input direction already.
103	*/
104	TK_SDA_DIR(0);
105
106	for (i = 8; i--;) {
107	TK_SCL_OUT(0);
108	tempudelay(1);
109	x >>= 1;
110	x \|= (TK_SDA_IN() << 7);
111	TK_SCL_OUT(1);
112	tempudelay(1);
113	}
114
115	return x;
116	}
117
118	/* Prepares for a transaction by de-activating RST (active-low). */
119
120	static void
121	start(void)
122	{
123	TK_SCL_OUT(0);
124	tempudelay(1);
125	TK_RST_OUT(0);
126	tempudelay(5);
127	TK_RST_OUT(1);
128	}
129
130	/* Ends a transaction by taking RST active again. */
131
132	static void
133	stop(void)
134	{
135	tempudelay(2);
136	TK_RST_OUT(0);
137	}
138
139	/* Enable writing. */
140
141	static void
142	ds1302_wenable(void)
143	{
144	start();
145	out_byte(0x8e); /* Write control register */
146	out_byte(0x00); /* Disable write protect bit 7 = 0 */
147	stop();
148	}
149
150	/* Disable writing. */
151
152	static void
153	ds1302_wdisable(void)
154	{
155	start();
156	out_byte(0x8e); /* Write control register */
157	out_byte(0x80); /* Disable write protect bit 7 = 0 */
158	stop();
159	}
160
161
162
163	/* Read a byte from the selected register in the DS1302. */
164
165	unsigned char
166	ds1302_readreg(int reg)
167	{
168	unsigned char x;
169
170	start();
171	out_byte(0x81 \| (reg << 1)); /* read register */
172	x = in_byte();
173	stop();
174
175	return x;
176	}
177
178	/* Write a byte to the selected register. */
179
180	void
181	ds1302_writereg(int reg, unsigned char val)
182	{
183	#ifndef CONFIG_ETRAX_RTC_READONLY
184	int do_writereg = 1;
185	#else
186	int do_writereg = 0;
187
188	if (reg == RTC_TRICKLECHARGER)
189	do_writereg = 1;
190	#endif
191
192	if (do_writereg) {
193	ds1302_wenable();
194	start();
195	out_byte(0x80 \| (reg << 1)); /* write register */
196	out_byte(val);
197	stop();
198	ds1302_wdisable();
199	}
200	}
201
202	void
203	get_rtc_time(struct rtc_time *rtc_tm)
204	{
205	unsigned long flags;
206
207	local_irq_save(flags);
1da177e4 LT	208
	209	rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS);
	210	rtc_tm->tm_min = CMOS_READ(RTC_MINUTES);
	211	rtc_tm->tm_hour = CMOS_READ(RTC_HOURS);
	212	rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
	213	rtc_tm->tm_mon = CMOS_READ(RTC_MONTH);
	214	rtc_tm->tm_year = CMOS_READ(RTC_YEAR);
	215
	216	local_irq_restore(flags);
	217
4110a0d6 AB	218	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
	219	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
	220	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
	221	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
	222	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
	223	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
1da177e4 LT	224
	225	/*
	226	* Account for differences between how the RTC uses the values
	227	* and how they are defined in a struct rtc_time;
	228	*/
	229
	230	if (rtc_tm->tm_year <= 69)
	231	rtc_tm->tm_year += 100;
	232
	233	rtc_tm->tm_mon--;
	234	}
	235
	236	static unsigned char days_in_mo[] =
	237	{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
	238
	239	/* ioctl that supports RTC_RD_TIME and RTC_SET_TIME (read and set time/date). */
	240
	241	static int
	242	rtc_ioctl(struct inode inode, struct file file, unsigned int cmd,
	243	unsigned long arg)
	244	{
7e920426	245	unsigned long flags;
1da177e4 LT	246
	247	switch(cmd) {
	248	case RTC_RD_TIME: /* read the time/date from RTC */
	249	{
	250	struct rtc_time rtc_tm;
	251
	252	memset(&rtc_tm, 0, sizeof (struct rtc_time));
	253	get_rtc_time(&rtc_tm);
	254	if (copy_to_user((struct rtc_time*)arg, &rtc_tm, sizeof(struct rtc_time)))
	255	return -EFAULT;
	256	return 0;
	257	}
	258
	259	case RTC_SET_TIME: /* set the RTC */
	260	{
	261	struct rtc_time rtc_tm;
	262	unsigned char mon, day, hrs, min, sec, leap_yr;
	263	unsigned int yrs;
	264
	265	if (!capable(CAP_SYS_TIME))
	266	return -EPERM;
	267
	268	if (copy_from_user(&rtc_tm, (struct rtc_time*)arg, sizeof(struct rtc_time)))
7e920426	269	return -EFAULT;
1da177e4 LT	270
	271	yrs = rtc_tm.tm_year + 1900;
	272	mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
	273	day = rtc_tm.tm_mday;
	274	hrs = rtc_tm.tm_hour;
	275	min = rtc_tm.tm_min;
	276	sec = rtc_tm.tm_sec;
	277
	278
	279	if ((yrs < 1970) \|\| (yrs > 2069))
	280	return -EINVAL;
	281
	282	leap_yr = ((!(yrs % 4) && (yrs % 100)) \|\| !(yrs % 400));
	283
	284	if ((mon > 12) \|\| (day == 0))
	285	return -EINVAL;
	286
	287	if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
	288	return -EINVAL;
	289
	290	if ((hrs >= 24) \|\| (min >= 60) \|\| (sec >= 60))
	291	return -EINVAL;
	292
	293	if (yrs >= 2000)
	294	yrs -= 2000; /* RTC (0, 1, ... 69) */
	295	else
	296	yrs -= 1900; /* RTC (70, 71, ... 99) */
	297
4110a0d6 AB	298	sec = bin2bcd(sec);
	299	min = bin2bcd(min);
	300	hrs = bin2bcd(hrs);
	301	day = bin2bcd(day);
	302	mon = bin2bcd(mon);
	303	yrs = bin2bcd(yrs);
1da177e4 LT	304
1da177e4 LT	305	local_irq_save(flags);
1da177e4 LT	306	CMOS_WRITE(yrs, RTC_YEAR);
	307	CMOS_WRITE(mon, RTC_MONTH);
	308	CMOS_WRITE(day, RTC_DAY_OF_MONTH);
	309	CMOS_WRITE(hrs, RTC_HOURS);
	310	CMOS_WRITE(min, RTC_MINUTES);
	311	CMOS_WRITE(sec, RTC_SECONDS);
	312	local_irq_restore(flags);
	313
	314	/* Notice that at this point, the RTC is updated but
	315	* the kernel is still running with the old time.
	316	* You need to set that separately with settimeofday
	317	* or adjtimex.
	318	*/
	319	return 0;
	320	}
	321
	322	case RTC_SET_CHARGE: /* set the RTC TRICKLE CHARGE register */
	323	{
7e920426	324	int tcs_val;
1da177e4 LT	325
	326	if (!capable(CAP_SYS_TIME))
	327	return -EPERM;
	328
	329	if(copy_from_user(&tcs_val, (int*)arg, sizeof(int)))
	330	return -EFAULT;
	331
	332	tcs_val = RTC_TCR_PATTERN \| (tcs_val & 0x0F);
	333	ds1302_writereg(RTC_TRICKLECHARGER, tcs_val);
	334	return 0;
	335	}
8f297252	336	case RTC_VL_READ:
1da177e4 LT	337	{
	338	/* TODO:
	339	* Implement voltage low detection support
	340	*/
	341	printk(KERN_WARNING "DS1302: RTC Voltage Low detection"
	342	" is not supported\n");
	343	return 0;
	344	}
8f297252	345	case RTC_VL_CLR:
1da177e4 LT	346	{
	347	/* TODO:
	348	* Nothing to do since Voltage Low detection is not supported
	349	*/
	350	return 0;
	351	}
	352	default:
	353	return -ENOIOCTLCMD;
	354	}
	355	}
	356
	357	static void
	358	print_rtc_status(void)
	359	{
	360	struct rtc_time tm;
	361
	362	get_rtc_time(&tm);
	363
	364	/*
	365	* There is no way to tell if the luser has the RTC set for local
	366	* time or for Universal Standard Time (GMT). Probably local though.
	367	*/
	368
	369	printk(KERN_INFO "rtc_time\t: %02d:%02d:%02d\n",
	370	tm.tm_hour, tm.tm_min, tm.tm_sec);
	371	printk(KERN_INFO "rtc_date\t: %04d-%02d-%02d\n",
	372	tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
	373	}
	374
	375	/* The various file operations we support. */
	376
5dfe4c96	377	static const struct file_operations rtc_fops = {
7e920426 MS	378	.owner = THIS_MODULE,
7e920426 MS	379	.ioctl = rtc_ioctl,
1da177e4 LT	380	};
	381
	382	/* Probe for the chip by writing something to its RAM and try reading it back. */
	383
	384	#define MAGIC_PATTERN 0x42
	385
	386	static int __init
	387	ds1302_probe(void)
	388	{
	389	int retval, res;
	390
	391	TK_RST_DIR(1);
	392	TK_SCL_DIR(1);
	393	TK_SDA_DIR(0);
	394
	395	/* Try to talk to timekeeper. */
	396
	397	ds1302_wenable();
	398	start();
	399	out_byte(0xc0); /* write RAM byte 0 */
	400	out_byte(MAGIC_PATTERN); /* write something magic */
	401	start();
	402	out_byte(0xc1); /* read RAM byte 0 */
	403
	404	if((res = in_byte()) == MAGIC_PATTERN) {
	405	stop();
	406	ds1302_wdisable();
	407	printk(KERN_INFO "%s: RTC found.\n", ds1302_name);
	408	printk(KERN_INFO "%s: SDA, SCL, RST on PB%i, PB%i, %s%i\n",
	409	ds1302_name,
	410	CONFIG_ETRAX_DS1302_SDABIT,
	411	CONFIG_ETRAX_DS1302_SCLBIT,
	412	#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
	413	"GENIO",
	414	#else
	415	"PB",
	416	#endif
	417	CONFIG_ETRAX_DS1302_RSTBIT);
7e920426	418	print_rtc_status();
1da177e4 LT	419	retval = 1;
	420	} else {
	421	stop();
	422	retval = 0;
	423	}
	424
	425	return retval;
	426	}
	427
	428
	429	/* Just probe for the RTC and register the device to handle the ioctl needed. */
	430
	431	int __init
	432	ds1302_init(void)
	433	{
7e920426	434	#ifdef CONFIG_ETRAX_I2C
1da177e4	435	i2c_init();
7e920426	436	#endif
1da177e4 LT	437
	438	if (!ds1302_probe()) {
	439	#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
	440	#if CONFIG_ETRAX_DS1302_RSTBIT == 27
	441	/*
	442	* The only way to set g27 to output is to enable ATA.
	443	*
	444	* Make sure that R_GEN_CONFIG is setup correct.
	445	*/
7e920426 MS	446	/* Allocating the ATA interface will grab almost all
	447	* pins in I/O groups a, b, c and d. A consequence of
	448	* allocating the ATA interface is that the fixed
	449	* interfaces shared RAM, parallel port 0, parallel
	450	* port 1, parallel port W, SCSI-8 port 0, SCSI-8 port
	451	* 1, SCSI-W, serial port 2, serial port 3,
	452	* synchronous serial port 3 and USB port 2 and almost
	453	* all GPIO pins on port g cannot be used.
	454	*/
	455	if (cris_request_io_interface(if_ata, "ds1302/ATA")) {
	456	printk(KERN_WARNING "ds1302: Failed to get IO interface\n");
	457	return -1;
	458	}
	459
1da177e4	460	#elif CONFIG_ETRAX_DS1302_RSTBIT == 0
7e920426 MS	461	if (cris_io_interface_allocate_pins(if_gpio_grp_a,
	462	'g',
	463	CONFIG_ETRAX_DS1302_RSTBIT,
	464	CONFIG_ETRAX_DS1302_RSTBIT)) {
	465	printk(KERN_WARNING "ds1302: Failed to get IO interface\n");
	466	return -1;
	467	}
	468
	469	/* Set the direction of this bit to out. */
	470	genconfig_shadow = ((genconfig_shadow &
	471	~IO_MASK(R_GEN_CONFIG, g0dir)) \|
	472	(IO_STATE(R_GEN_CONFIG, g0dir, out)));
	473	*R_GEN_CONFIG = genconfig_shadow;
1da177e4 LT	474	#endif
	475	if (!ds1302_probe()) {
	476	printk(KERN_WARNING "%s: RTC not found.\n", ds1302_name);
7e920426	477	return -1;
1da177e4 LT	478	}
	479	#else
	480	printk(KERN_WARNING "%s: RTC not found.\n", ds1302_name);
7e920426	481	return -1;
1da177e4 LT	482	#endif
	483	}
	484	/* Initialise trickle charger */
	485	ds1302_writereg(RTC_TRICKLECHARGER,
	486	RTC_TCR_PATTERN \|(CONFIG_ETRAX_DS1302_TRICKLE_CHARGE & 0x0F));
	487	/* Start clock by resetting CLOCK_HALT */
	488	ds1302_writereg(RTC_SECONDS, (ds1302_readreg(RTC_SECONDS) & 0x7F));
	489	return 0;
	490	}
	491
	492	static int __init ds1302_register(void)
	493	{
	494	ds1302_init();
	495	if (register_chrdev(RTC_MAJOR_NR, ds1302_name, &rtc_fops)) {
	496	printk(KERN_INFO "%s: unable to get major %d for rtc\n",
	497	ds1302_name, RTC_MAJOR_NR);
	498	return -1;
	499	}
	500	return 0;
	501
	502	}
	503
	504	module_init(ds1302_register);