/* * An I2C driver for the Philips PCF8563 RTC * Copyright 2005-06 Tower Technologies * * Author: Alessandro Zummo <a.zummo@towertech.it> * Maintainers: http://www.nslu2-linux.org/ * * based on the other drivers in this same directory. * * http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/i2c.h>#include <linux/bcd.h>#include <linux/rtc.h> #define DRV_VERSION "0.4.2" /* Addresses to scan: none * This chip cannot be reliably autodetected. An empty eeprom * located at 0x51 will pass the validation routine due to * the way the registers are implemented. */static unsigned short normal_i2c[] = { I2C_CLIENT_END }; /* Module parameters */I2C_CLIENT_INSMOD; #define PCF8563_REG_ST1		0x00 /* status */#define PCF8563_REG_ST2		0x01 #define PCF8563_REG_SC		0x02 /* datetime */#define PCF8563_REG_MN		0x03#define PCF8563_REG_HR		0x04#define PCF8563_REG_DM		0x05#define PCF8563_REG_DW		0x06#define PCF8563_REG_MO		0x07#define PCF8563_REG_YR		0x08 #define PCF8563_REG_AMN		0x09 /* alarm */#define PCF8563_REG_AHR		0x0A#define PCF8563_REG_ADM		0x0B#define PCF8563_REG_ADW		0x0C #define PCF8563_REG_CLKO	0x0D /* clock out */#define PCF8563_REG_TMRC	0x0E /* timer control */#define PCF8563_REG_TMR		0x0F /* timer */ #define PCF8563_SC_LV		0x80 /* low voltage */#define PCF8563_MO_C		0x80 /* century */ struct pcf8563 {	struct i2c_client client;	/*	 * The meaning of MO_C bit varies by the chip type.	 * From PCF8563 datasheet: this bit is toggled when the years	 * register overflows from 99 to 00	 *   0 indicates the century is 20xx	 *   1 indicates the century is 19xx	 * From RTC8564 datasheet: this bit indicates change of	 * century. When the year digit data overflows from 99 to 00,	 * this bit is set. By presetting it to 0 while still in the	 * 20th century, it will be set in year 2000, ...	 * There seems no reliable way to know how the system use this	 * bit.  So let's do it heuristically, assuming we are live in	 * 1970...2069.	 */	int c_polarity;	/* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */}; static int pcf8563_probe(struct i2c_adapter *adapter, int address, int kind);static int pcf8563_detach(struct i2c_client *client); /* * In the routines that deal directly with the pcf8563 hardware, we use * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. */static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm){	struct pcf8563 *pcf8563 = container_of(client, struct pcf8563, client);	unsigned char buf[13] = { PCF8563_REG_ST1 }; 	struct i2c_msg msgs[] = {		{ client->addr, 0, 1, buf },	/* setup read ptr */		{ client->addr, I2C_M_RD, 13, buf },	/* read status + date */	}; 	/* read registers */	if ((i2c_transfer(client->adapter, msgs, 2)) != 2) {		dev_err(&client->dev, "%s: read error\n", __FUNCTION__);		return -EIO;	} 	if (buf[PCF8563_REG_SC] & PCF8563_SC_LV)		dev_info(&client->dev,			"low voltage detected, date/time is not reliable.\n"); 	dev_dbg(&client->dev,		"%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, "		"mday=%02x, wday=%02x, mon=%02x, year=%02x\n",		__FUNCTION__,		buf[0], buf[1], buf[2], buf[3],		buf[4], buf[5], buf[6], buf[7],		buf[8]);  	tm->tm_sec = BCD2BIN(buf[PCF8563_REG_SC] & 0x7F);	tm->tm_min = BCD2BIN(buf[PCF8563_REG_MN] & 0x7F);	tm->tm_hour = BCD2BIN(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */	tm->tm_mday = BCD2BIN(buf[PCF8563_REG_DM] & 0x3F);	tm->tm_wday = buf[PCF8563_REG_DW] & 0x07;	tm->tm_mon = BCD2BIN(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */	tm->tm_year = BCD2BIN(buf[PCF8563_REG_YR]);	if (tm->tm_year < 70)		tm->tm_year += 100;	/* assume we are in 1970...2069 */	/* detect the polarity heuristically. see note above. */	pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ?		(tm->tm_year >= 100) : (tm->tm_year < 100); 	dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "		"mday=%d, mon=%d, year=%d, wday=%d\n",		__FUNCTION__,		tm->tm_sec, tm->tm_min, tm->tm_hour,		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 	/* the clock can give out invalid datetime, but we cannot return	 * -EINVAL otherwise hwclock will refuse to set the time on bootup.	 */	if (rtc_valid_tm(tm) < 0)		dev_err(&client->dev, "retrieved date/time is not valid.\n"); 	return 0;} static int pcf8563_set_datetime(struct i2c_client *client, struct rtc_time *tm){	struct pcf8563 *pcf8563 = container_of(client, struct pcf8563, client);	int i, err;	unsigned char buf[9]; 	dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, "		"mday=%d, mon=%d, year=%d, wday=%d\n",		__FUNCTION__,		tm->tm_sec, tm->tm_min, tm->tm_hour,		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 	/* hours, minutes and seconds */	buf[PCF8563_REG_SC] = BIN2BCD(tm->tm_sec);	buf[PCF8563_REG_MN] = BIN2BCD(tm->tm_min);	buf[PCF8563_REG_HR] = BIN2BCD(tm->tm_hour); 	buf[PCF8563_REG_DM] = BIN2BCD(tm->tm_mday); 	/* month, 1 - 12 */	buf[PCF8563_REG_MO] = BIN2BCD(tm->tm_mon + 1); 	/* year and century */	buf[PCF8563_REG_YR] = BIN2BCD(tm->tm_year % 100);	if (pcf8563->c_polarity ? (tm->tm_year >= 100) : (tm->tm_year < 100))		buf[PCF8563_REG_MO] |= PCF8563_MO_C; 	buf[PCF8563_REG_DW] = tm->tm_wday & 0x07; 	/* write register's data */	for (i = 0; i < 7; i++) {		unsigned char data[2] = { PCF8563_REG_SC + i,						buf[PCF8563_REG_SC + i] }; 		err = i2c_master_send(client, data, sizeof(data));		if (err != sizeof(data)) {			dev_err(&client->dev,				"%s: err=%d addr=%02x, data=%02x\n",				__FUNCTION__, err, data[0], data[1]);			return -EIO;		}	}; 	return 0;} struct pcf8563_limit{	unsigned char reg;	unsigned char mask;	unsigned char min;	unsigned char max;}; static int pcf8563_validate_client(struct i2c_client *client){	int i; 	static const struct pcf8563_limit pattern[] = {		/* register, mask, min, max */		{ PCF8563_REG_SC,	0x7F,	0,	59	},		{ PCF8563_REG_MN,	0x7F,	0,	59	},		{ PCF8563_REG_HR,	0x3F,	0,	23	},		{ PCF8563_REG_DM,	0x3F,	0,	31	},		{ PCF8563_REG_MO,	0x1F,	0,	12	},	}; 	/* check limits (only registers with bcd values) */	for (i = 0; i < ARRAY_SIZE(pattern); i++) {		int xfer;		unsigned char value;		unsigned char buf = pattern[i].reg; 		struct i2c_msg msgs[] = {			{ client->addr, 0, 1, &buf },			{ client->addr, I2C_M_RD, 1, &buf },		}; 		xfer = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); 		if (xfer != ARRAY_SIZE(msgs)) {			dev_err(&client->dev,				"%s: could not read register 0x%02X\n",				__FUNCTION__, pattern[i].reg); 			return -EIO;		} 		value = BCD2BIN(buf & pattern[i].mask); 		if (value > pattern[i].max ||			value < pattern[i].min) {			dev_dbg(&client->dev,				"%s: pattern=%d, reg=%x, mask=0x%02x, min=%d, "				"max=%d, value=%d, raw=0x%02X\n",				__FUNCTION__, i, pattern[i].reg, pattern[i].mask,				pattern[i].min, pattern[i].max,				value, buf); 			return -ENODEV;		}	} 	return 0;} static int pcf8563_rtc_read_time(struct device *dev, struct rtc_time *tm){	return pcf8563_get_datetime(to_i2c_client(dev), tm);} static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm){	return pcf8563_set_datetime(to_i2c_client(dev), tm);} static const struct rtc_class_ops pcf8563_rtc_ops = {	.read_time	= pcf8563_rtc_read_time,	.set_time	= pcf8563_rtc_set_time,}; static int pcf8563_attach(struct i2c_adapter *adapter){	return i2c_probe(adapter, &addr_data, pcf8563_probe);} static struct i2c_driver pcf8563_driver = {	.driver		= {		.name	= "pcf8563",	},	.id		= I2C_DRIVERID_PCF8563,	.attach_adapter = &pcf8563_attach,	.detach_client	= &pcf8563_detach,}; static int pcf8563_probe(struct i2c_adapter *adapter, int address, int kind){	struct pcf8563 *pcf8563;	struct i2c_client *client;	struct rtc_device *rtc; 	int err = 0; 	dev_dbg(&adapter->dev, "%s\n", __FUNCTION__); 	if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {		err = -ENODEV;		goto exit;	} 	if (!(pcf8563 = kzalloc(sizeof(struct pcf8563), GFP_KERNEL))) {		err = -ENOMEM;		goto exit;	} 	client = &pcf8563->client;	client->addr = address;	client->driver = &pcf8563_driver;	client->adapter	= adapter; 	strlcpy(client->name, pcf8563_driver.driver.name, I2C_NAME_SIZE); 	/* Verify the chip is really an PCF8563 */	if (kind < 0) {		if (pcf8563_validate_client(client) < 0) {			err = -ENODEV;			goto exit_kfree;		}	} 	/* Inform the i2c layer */	if ((err = i2c_attach_client(client)))		goto exit_kfree; 	dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); 	rtc = rtc_device_register(pcf8563_driver.driver.name, &client->dev,				&pcf8563_rtc_ops, THIS_MODULE); 	if (IS_ERR(rtc)) {		err = PTR_ERR(rtc);		goto exit_detach;	} 	i2c_set_clientdata(client, rtc); 	return 0; exit_detach:	i2c_detach_client(client); exit_kfree:	kfree(pcf8563); exit:	return err;} static int pcf8563_detach(struct i2c_client *client){	struct pcf8563 *pcf8563 = container_of(client, struct pcf8563, client);	int err;	struct rtc_device *rtc = i2c_get_clientdata(client); 	if (rtc)		rtc_device_unregister(rtc); 	if ((err = i2c_detach_client(client)))		return err; 	kfree(pcf8563); 	return 0;} static int __init pcf8563_init(void){	return i2c_add_driver(&pcf8563_driver);} static void __exit pcf8563_exit(void){	i2c_del_driver(&pcf8563_driver);} MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver");MODULE_LICENSE("GPL");MODULE_VERSION(DRV_VERSION); module_init(pcf8563_init);module_exit(pcf8563_exit);