[linux-2.6-block.git] / drivers / rtc / rtc-pcf8563.c

/*
 * 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>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/err.h>

#define DRV_VERSION "0.4.3"

#define PCF8563_REG_ST1		0x00 /* status */
#define PCF8563_REG_ST2		0x01
#define PCF8563_BIT_AIE		(1 << 1)
#define PCF8563_BIT_AF		(1 << 3)
#define PCF8563_BITS_ST2_N	(7 << 5)

#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_CLKO	0x0D /* clock out */
#define PCF8563_REG_TMRC	0x0E /* timer control */
#define PCF8563_TMRC_ENABLE	BIT(7)
#define PCF8563_TMRC_4096	0
#define PCF8563_TMRC_64		1
#define PCF8563_TMRC_1		2
#define PCF8563_TMRC_1_60	3
#define PCF8563_TMRC_MASK	3

#define PCF8563_REG_TMR		0x0F /* timer */

#define PCF8563_SC_LV		0x80 /* low voltage */
#define PCF8563_MO_C		0x80 /* century */

static struct i2c_driver pcf8563_driver;

struct pcf8563 {
	struct rtc_device *rtc;
	/*
	 * 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 */
	int voltage_low; /* incicates if a low_voltage was detected */

	struct i2c_client *client;
};

static int pcf8563_read_block_data(struct i2c_client *client, unsigned char reg,
				   unsigned char length, unsigned char *buf)
{
	struct i2c_msg msgs[] = {
		{/* setup read ptr */
			.addr = client->addr,
			.len = 1,
			.buf = &reg,
		},
		{
			.addr = client->addr,
			.flags = I2C_M_RD,
			.len = length,
			.buf = buf
		},
	};

	if ((i2c_transfer(client->adapter, msgs, 2)) != 2) {
		dev_err(&client->dev, "%s: read error\n", __func__);
		return -EIO;
	}

	return 0;
}

static int pcf8563_write_block_data(struct i2c_client *client,
				   unsigned char reg, unsigned char length,
				   unsigned char *buf)
{
	int i, err;

	for (i = 0; i < length; i++) {
		unsigned char data[2] = { reg + i, buf[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",
				__func__, err, data[0], data[1]);
			return -EIO;
		}
	}

	return 0;
}

static int pcf8563_set_alarm_mode(struct i2c_client *client, bool on)
{
	unsigned char buf;
	int err;

	err = pcf8563_read_block_data(client, PCF8563_REG_ST2, 1, &buf);
	if (err < 0)
		return err;

	if (on)
		buf |= PCF8563_BIT_AIE;
	else
		buf &= ~PCF8563_BIT_AIE;

	buf &= ~(PCF8563_BIT_AF | PCF8563_BITS_ST2_N);

	err = pcf8563_write_block_data(client, PCF8563_REG_ST2, 1, &buf);
	if (err < 0) {
		dev_err(&client->dev, "%s: write error\n", __func__);
		return -EIO;
	}

	return 0;
}

static int pcf8563_get_alarm_mode(struct i2c_client *client, unsigned char *en,
				  unsigned char *pen)
{
	unsigned char buf;
	int err;

	err = pcf8563_read_block_data(client, PCF8563_REG_ST2, 1, &buf);
	if (err)
		return err;

	if (en)
		*en = !!(buf & PCF8563_BIT_AIE);
	if (pen)
		*pen = !!(buf & PCF8563_BIT_AF);

	return 0;
}

static irqreturn_t pcf8563_irq(int irq, void *dev_id)
{
	struct pcf8563 *pcf8563 = i2c_get_clientdata(dev_id);
	int err;
	char pending;

	err = pcf8563_get_alarm_mode(pcf8563->client, NULL, &pending);
	if (err)
		return IRQ_NONE;

	if (pending) {
		rtc_update_irq(pcf8563->rtc, 1, RTC_IRQF | RTC_AF);
		pcf8563_set_alarm_mode(pcf8563->client, 1);
		return IRQ_HANDLED;
	}

	return IRQ_NONE;
}

/*
 * 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 = i2c_get_clientdata(client);
	unsigned char buf[9];
	int err;

	err = pcf8563_read_block_data(client, PCF8563_REG_ST1, 9, buf);
	if (err)
		return err;

	if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) {
		pcf8563->voltage_low = 1;
		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",
		__func__,
		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",
		__func__,
		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 = i2c_get_clientdata(client);
	int 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",
		__func__,
		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;

	err = pcf8563_write_block_data(client, PCF8563_REG_SC,
				9 - PCF8563_REG_SC, buf + PCF8563_REG_SC);
	if (err)
		return err;

	return 0;
}

#ifdef CONFIG_RTC_INTF_DEV
static int pcf8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
	struct pcf8563 *pcf8563 = i2c_get_clientdata(to_i2c_client(dev));
	struct rtc_time tm;

	switch (cmd) {
	case RTC_VL_READ:
		if (pcf8563->voltage_low)
			dev_info(dev, "low voltage detected, date/time is not reliable.\n");

		if (copy_to_user((void __user *)arg, &pcf8563->voltage_low,
					sizeof(int)))
			return -EFAULT;
		return 0;
	case RTC_VL_CLR:
		/*
		 * Clear the VL bit in the seconds register in case
		 * the time has not been set already (which would
		 * have cleared it). This does not really matter
		 * because of the cached voltage_low value but do it
		 * anyway for consistency.
		 */
		if (pcf8563_get_datetime(to_i2c_client(dev), &tm))
			pcf8563_set_datetime(to_i2c_client(dev), &tm);

		/* Clear the cached value. */
		pcf8563->voltage_low = 0;

		return 0;
	default:
		return -ENOIOCTLCMD;
	}
}
#else
#define pcf8563_rtc_ioctl NULL
#endif

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 int pcf8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned char buf[4];
	int err;

	err = pcf8563_read_block_data(client, PCF8563_REG_AMN, 4, buf);
	if (err)
		return err;

	dev_dbg(&client->dev,
		"%s: raw data is min=%02x, hr=%02x, mday=%02x, wday=%02x\n",
		__func__, buf[0], buf[1], buf[2], buf[3]);

	tm->time.tm_min = bcd2bin(buf[0] & 0x7F);
	tm->time.tm_hour = bcd2bin(buf[1] & 0x3F);
	tm->time.tm_mday = bcd2bin(buf[2] & 0x3F);
	tm->time.tm_wday = bcd2bin(buf[3] & 0x7);
	tm->time.tm_mon = -1;
	tm->time.tm_year = -1;
	tm->time.tm_yday = -1;
	tm->time.tm_isdst = -1;

	err = pcf8563_get_alarm_mode(client, &tm->enabled, &tm->pending);
	if (err < 0)
		return err;

	dev_dbg(&client->dev, "%s: tm is mins=%d, hours=%d, mday=%d, wday=%d,"
		" enabled=%d, pending=%d\n", __func__, tm->time.tm_min,
		tm->time.tm_hour, tm->time.tm_mday, tm->time.tm_wday,
		tm->enabled, tm->pending);

	return 0;
}

static int pcf8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned char buf[4];
	int err;
	unsigned long alarm_time;

	/* The alarm has no seconds, round up to nearest minute */
	if (tm->time.tm_sec) {
		rtc_tm_to_time(&tm->time, &alarm_time);
		alarm_time += 60-tm->time.tm_sec;
		rtc_time_to_tm(alarm_time, &tm->time);
	}

	dev_dbg(dev, "%s, min=%d hour=%d wday=%d mday=%d "
		"enabled=%d pending=%d\n", __func__,
		tm->time.tm_min, tm->time.tm_hour, tm->time.tm_wday,
		tm->time.tm_mday, tm->enabled, tm->pending);

	buf[0] = bin2bcd(tm->time.tm_min);
	buf[1] = bin2bcd(tm->time.tm_hour);
	buf[2] = bin2bcd(tm->time.tm_mday);
	buf[3] = tm->time.tm_wday & 0x07;

	err = pcf8563_write_block_data(client, PCF8563_REG_AMN, 4, buf);
	if (err)
		return err;

	return pcf8563_set_alarm_mode(client, 1);
}

static int pcf8563_irq_enable(struct device *dev, unsigned int enabled)
{
	dev_dbg(dev, "%s: en=%d\n", __func__, enabled);
	return pcf8563_set_alarm_mode(to_i2c_client(dev), !!enabled);
}

static const struct rtc_class_ops pcf8563_rtc_ops = {
	.ioctl		= pcf8563_rtc_ioctl,
	.read_time	= pcf8563_rtc_read_time,
	.set_time	= pcf8563_rtc_set_time,
	.read_alarm	= pcf8563_rtc_read_alarm,
	.set_alarm	= pcf8563_rtc_set_alarm,
	.alarm_irq_enable = pcf8563_irq_enable,
};

static int pcf8563_probe(struct i2c_client *client,
				const struct i2c_device_id *id)
{
	struct pcf8563 *pcf8563;
	int err;
	unsigned char buf;
	unsigned char alm_pending;

	dev_dbg(&client->dev, "%s\n", __func__);

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
		return -ENODEV;

	pcf8563 = devm_kzalloc(&client->dev, sizeof(struct pcf8563),
				GFP_KERNEL);
	if (!pcf8563)
		return -ENOMEM;

	dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");

	i2c_set_clientdata(client, pcf8563);
	pcf8563->client = client;
	device_set_wakeup_capable(&client->dev, 1);

	/* Set timer to lowest frequency to save power (ref Haoyu datasheet) */
	buf = PCF8563_TMRC_1_60;
	err = pcf8563_write_block_data(client, PCF8563_REG_TMRC, 1, &buf);
	if (err < 0) {
		dev_err(&client->dev, "%s: write error\n", __func__);
		return err;
	}

	err = pcf8563_get_alarm_mode(client, NULL, &alm_pending);
	if (err < 0) {
		dev_err(&client->dev, "%s: read error\n", __func__);
		return err;
	}
	if (alm_pending)
		pcf8563_set_alarm_mode(client, 0);

	pcf8563->rtc = devm_rtc_device_register(&client->dev,
				pcf8563_driver.driver.name,
				&pcf8563_rtc_ops, THIS_MODULE);

	if (IS_ERR(pcf8563->rtc))
		return PTR_ERR(pcf8563->rtc);

	if (client->irq > 0) {
		err = devm_request_threaded_irq(&client->dev, client->irq,
				NULL, pcf8563_irq,
				IRQF_SHARED|IRQF_ONESHOT|IRQF_TRIGGER_FALLING,
				pcf8563->rtc->name, client);
		if (err) {
			dev_err(&client->dev, "unable to request IRQ %d\n",
								client->irq);
			return err;
		}

	}

	/* the pcf8563 alarm only supports a minute accuracy */
	pcf8563->rtc->uie_unsupported = 1;

	return 0;
}

static const struct i2c_device_id pcf8563_id[] = {
	{ "pcf8563", 0 },
	{ "rtc8564", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, pcf8563_id);

#ifdef CONFIG_OF
static const struct of_device_id pcf8563_of_match[] = {
	{ .compatible = "nxp,pcf8563" },
	{}
};
MODULE_DEVICE_TABLE(of, pcf8563_of_match);
#endif

static struct i2c_driver pcf8563_driver = {
	.driver		= {
		.name	= "rtc-pcf8563",
		.owner	= THIS_MODULE,
		.of_match_table = of_match_ptr(pcf8563_of_match),
	},
	.probe		= pcf8563_probe,
	.id_table	= pcf8563_id,
};

module_i2c_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);
Commit	Line	Data
b5a82d62 AZ	1	/*
	2	* An I2C driver for the Philips PCF8563 RTC
	3	* Copyright 2005-06 Tower Technologies
	4	*
	5	* Author: Alessandro Zummo <a.zummo@towertech.it>
	6	* Maintainers: http://www.nslu2-linux.org/
	7	*
	8	* based on the other drivers in this same directory.
	9	*
	10	* http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf
	11	*
	12	* This program is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU General Public License version 2 as
	14	* published by the Free Software Foundation.
	15	*/
	16
	17	#include <linux/i2c.h>
	18	#include <linux/bcd.h>
	19	#include <linux/rtc.h>
5a0e3ad6	20	#include <linux/slab.h>
2113852b	21	#include <linux/module.h>
8dccaf06	22	#include <linux/of.h>
23f809ee	23	#include <linux/err.h>
b5a82d62	24
e5fc9cc0	25	#define DRV_VERSION "0.4.3"
b5a82d62 AZ	26
	27	#define PCF8563_REG_ST1 0x00 /* status */
	28	#define PCF8563_REG_ST2 0x01
ede3e9d4 VD	29	#define PCF8563_BIT_AIE (1 << 1)
ede3e9d4 VD	30	#define PCF8563_BIT_AF (1 << 3)
45ef0458	31	#define PCF8563_BITS_ST2_N (7 << 5)
b5a82d62 AZ	32
	33	#define PCF8563_REG_SC 0x02 /* datetime */
	34	#define PCF8563_REG_MN 0x03
	35	#define PCF8563_REG_HR 0x04
	36	#define PCF8563_REG_DM 0x05
	37	#define PCF8563_REG_DW 0x06
	38	#define PCF8563_REG_MO 0x07
	39	#define PCF8563_REG_YR 0x08
	40
	41	#define PCF8563_REG_AMN 0x09 /* alarm */
b5a82d62 AZ	42
	43	#define PCF8563_REG_CLKO 0x0D /* clock out */
	44	#define PCF8563_REG_TMRC 0x0E /* timer control */
ff0bc501 JK	45	#define PCF8563_TMRC_ENABLE BIT(7)
	46	#define PCF8563_TMRC_4096 0
	47	#define PCF8563_TMRC_64 1
	48	#define PCF8563_TMRC_1 2
	49	#define PCF8563_TMRC_1_60 3
	50	#define PCF8563_TMRC_MASK 3
	51
b5a82d62 AZ	52	#define PCF8563_REG_TMR 0x0F /* timer */
	53
	54	#define PCF8563_SC_LV 0x80 /* low voltage */
	55	#define PCF8563_MO_C 0x80 /* century */
	56
e5fc9cc0 AZ	57	static struct i2c_driver pcf8563_driver;
e5fc9cc0 AZ	58
cbb94502	59	struct pcf8563 {
e5fc9cc0	60	struct rtc_device *rtc;
cbb94502 AN	61	/*
	62	* The meaning of MO_C bit varies by the chip type.
	63	* From PCF8563 datasheet: this bit is toggled when the years
	64	* register overflows from 99 to 00
	65	* 0 indicates the century is 20xx
	66	* 1 indicates the century is 19xx
	67	* From RTC8564 datasheet: this bit indicates change of
	68	* century. When the year digit data overflows from 99 to 00,
	69	* this bit is set. By presetting it to 0 while still in the
	70	* 20th century, it will be set in year 2000, ...
	71	* There seems no reliable way to know how the system use this
	72	* bit. So let's do it heuristically, assuming we are live in
	73	* 1970...2069.
	74	*/
	75	int c_polarity; /* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */
0f20b767	76	int voltage_low; /* incicates if a low_voltage was detected */
ede3e9d4 VD	77
ede3e9d4 VD	78	struct i2c_client *client;
cbb94502 AN	79	};
cbb94502 AN	80
2784366c VD	81	static int pcf8563_read_block_data(struct i2c_client *client, unsigned char reg,
2784366c VD	82	unsigned char length, unsigned char *buf)
b5a82d62	83	{
b5a82d62	84	struct i2c_msg msgs[] = {
755e4a4b S	85	{/* setup read ptr */
	86	.addr = client->addr,
	87	.len = 1,
2784366c	88	.buf = &reg,
755e4a4b	89	},
2784366c	90	{
755e4a4b S	91	.addr = client->addr,
755e4a4b S	92	.flags = I2C_M_RD,
2784366c	93	.len = length,
755e4a4b S	94	.buf = buf
755e4a4b S	95	},
b5a82d62 AZ	96	};
b5a82d62 AZ	97
b5a82d62	98	if ((i2c_transfer(client->adapter, msgs, 2)) != 2) {
2a4e2b87	99	dev_err(&client->dev, "%s: read error\n", __func__);
b5a82d62 AZ	100	return -EIO;
	101	}
	102
2784366c VD	103	return 0;
	104	}
	105
	106	static int pcf8563_write_block_data(struct i2c_client *client,
	107	unsigned char reg, unsigned char length,
	108	unsigned char *buf)
	109	{
	110	int i, err;
	111
	112	for (i = 0; i < length; i++) {
	113	unsigned char data[2] = { reg + i, buf[i] };
	114
	115	err = i2c_master_send(client, data, sizeof(data));
	116	if (err != sizeof(data)) {
	117	dev_err(&client->dev,
	118	"%s: err=%d addr=%02x, data=%02x\n",
	119	__func__, err, data[0], data[1]);
	120	return -EIO;
	121	}
	122	}
	123
	124	return 0;
	125	}
	126
ede3e9d4 VD	127	static int pcf8563_set_alarm_mode(struct i2c_client *client, bool on)
ede3e9d4 VD	128	{
17a1e5e8	129	unsigned char buf;
ede3e9d4 VD	130	int err;
ede3e9d4 VD	131
17a1e5e8	132	err = pcf8563_read_block_data(client, PCF8563_REG_ST2, 1, &buf);
ede3e9d4 VD	133	if (err < 0)
	134	return err;
	135
	136	if (on)
17a1e5e8	137	buf \|= PCF8563_BIT_AIE;
ede3e9d4	138	else
17a1e5e8	139	buf &= ~PCF8563_BIT_AIE;
ede3e9d4	140
45ef0458	141	buf &= ~(PCF8563_BIT_AF \| PCF8563_BITS_ST2_N);
ede3e9d4	142
17a1e5e8	143	err = pcf8563_write_block_data(client, PCF8563_REG_ST2, 1, &buf);
ede3e9d4 VD	144	if (err < 0) {
	145	dev_err(&client->dev, "%s: write error\n", __func__);
	146	return -EIO;
	147	}
	148
	149	return 0;
	150	}
	151
	152	static int pcf8563_get_alarm_mode(struct i2c_client client, unsigned char en,
	153	unsigned char *pen)
	154	{
	155	unsigned char buf;
	156	int err;
	157
	158	err = pcf8563_read_block_data(client, PCF8563_REG_ST2, 1, &buf);
	159	if (err)
	160	return err;
	161
	162	if (en)
	163	*en = !!(buf & PCF8563_BIT_AIE);
	164	if (pen)
	165	*pen = !!(buf & PCF8563_BIT_AF);
	166
	167	return 0;
	168	}
	169
	170	static irqreturn_t pcf8563_irq(int irq, void *dev_id)
	171	{
	172	struct pcf8563 *pcf8563 = i2c_get_clientdata(dev_id);
	173	int err;
	174	char pending;
	175
	176	err = pcf8563_get_alarm_mode(pcf8563->client, NULL, &pending);
e698a512	177	if (err)
3ff38237	178	return IRQ_NONE;
ede3e9d4 VD	179
	180	if (pending) {
	181	rtc_update_irq(pcf8563->rtc, 1, RTC_IRQF \| RTC_AF);
	182	pcf8563_set_alarm_mode(pcf8563->client, 1);
	183	return IRQ_HANDLED;
	184	}
	185
	186	return IRQ_NONE;
	187	}
	188
2784366c VD	189	/*
	190	* In the routines that deal directly with the pcf8563 hardware, we use
	191	* rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch.
	192	*/
	193	static int pcf8563_get_datetime(struct i2c_client client, struct rtc_time tm)
	194	{
	195	struct pcf8563 *pcf8563 = i2c_get_clientdata(client);
	196	unsigned char buf[9];
	197	int err;
	198
	199	err = pcf8563_read_block_data(client, PCF8563_REG_ST1, 9, buf);
	200	if (err)
	201	return err;
	202
0f20b767 AS	203	if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) {
0f20b767 AS	204	pcf8563->voltage_low = 1;
b5a82d62 AZ	205	dev_info(&client->dev,
b5a82d62 AZ	206	"low voltage detected, date/time is not reliable.\n");
0f20b767	207	}
b5a82d62 AZ	208
	209	dev_dbg(&client->dev,
	210	"%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, "
	211	"mday=%02x, wday=%02x, mon=%02x, year=%02x\n",
2a4e2b87	212	__func__,
b5a82d62 AZ	213	buf[0], buf[1], buf[2], buf[3],
	214	buf[4], buf[5], buf[6], buf[7],
	215	buf[8]);
	216
	217
fe20ba70 AB	218	tm->tm_sec = bcd2bin(buf[PCF8563_REG_SC] & 0x7F);
	219	tm->tm_min = bcd2bin(buf[PCF8563_REG_MN] & 0x7F);
	220	tm->tm_hour = bcd2bin(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */
	221	tm->tm_mday = bcd2bin(buf[PCF8563_REG_DM] & 0x3F);
b5a82d62	222	tm->tm_wday = buf[PCF8563_REG_DW] & 0x07;
fe20ba70 AB	223	tm->tm_mon = bcd2bin(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */
fe20ba70 AB	224	tm->tm_year = bcd2bin(buf[PCF8563_REG_YR]);
cbb94502 AN	225	if (tm->tm_year < 70)
	226	tm->tm_year += 100; /* assume we are in 1970...2069 */
	227	/* detect the polarity heuristically. see note above. */
	228	pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ?
	229	(tm->tm_year >= 100) : (tm->tm_year < 100);
b5a82d62 AZ	230
	231	dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
	232	"mday=%d, mon=%d, year=%d, wday=%d\n",
2a4e2b87	233	__func__,
b5a82d62 AZ	234	tm->tm_sec, tm->tm_min, tm->tm_hour,
	235	tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
	236
	237	/* the clock can give out invalid datetime, but we cannot return
	238	* -EINVAL otherwise hwclock will refuse to set the time on bootup.
	239	*/
	240	if (rtc_valid_tm(tm) < 0)
	241	dev_err(&client->dev, "retrieved date/time is not valid.\n");
	242
	243	return 0;
	244	}
	245
	246	static int pcf8563_set_datetime(struct i2c_client client, struct rtc_time tm)
	247	{
e5fc9cc0	248	struct pcf8563 *pcf8563 = i2c_get_clientdata(client);
2784366c	249	int err;
b5a82d62 AZ	250	unsigned char buf[9];
	251
	252	dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, "
	253	"mday=%d, mon=%d, year=%d, wday=%d\n",
2a4e2b87	254	__func__,
b5a82d62 AZ	255	tm->tm_sec, tm->tm_min, tm->tm_hour,
	256	tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
	257
	258	/* hours, minutes and seconds */
fe20ba70 AB	259	buf[PCF8563_REG_SC] = bin2bcd(tm->tm_sec);
	260	buf[PCF8563_REG_MN] = bin2bcd(tm->tm_min);
	261	buf[PCF8563_REG_HR] = bin2bcd(tm->tm_hour);
b5a82d62	262
fe20ba70	263	buf[PCF8563_REG_DM] = bin2bcd(tm->tm_mday);
b5a82d62 AZ	264
b5a82d62 AZ	265	/* month, 1 - 12 */
fe20ba70	266	buf[PCF8563_REG_MO] = bin2bcd(tm->tm_mon + 1);
b5a82d62 AZ	267
b5a82d62 AZ	268	/* year and century */
fe20ba70	269	buf[PCF8563_REG_YR] = bin2bcd(tm->tm_year % 100);
cbb94502	270	if (pcf8563->c_polarity ? (tm->tm_year >= 100) : (tm->tm_year < 100))
b5a82d62 AZ	271	buf[PCF8563_REG_MO] \|= PCF8563_MO_C;
	272
	273	buf[PCF8563_REG_DW] = tm->tm_wday & 0x07;
	274
2784366c VD	275	err = pcf8563_write_block_data(client, PCF8563_REG_SC,
	276	9 - PCF8563_REG_SC, buf + PCF8563_REG_SC);
	277	if (err)
	278	return err;
b5a82d62 AZ	279
	280	return 0;
	281	}
	282
0f20b767 AS	283	#ifdef CONFIG_RTC_INTF_DEV
	284	static int pcf8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
	285	{
	286	struct pcf8563 *pcf8563 = i2c_get_clientdata(to_i2c_client(dev));
	287	struct rtc_time tm;
	288
	289	switch (cmd) {
	290	case RTC_VL_READ:
	291	if (pcf8563->voltage_low)
	292	dev_info(dev, "low voltage detected, date/time is not reliable.\n");
	293
	294	if (copy_to_user((void __user *)arg, &pcf8563->voltage_low,
	295	sizeof(int)))
	296	return -EFAULT;
	297	return 0;
	298	case RTC_VL_CLR:
	299	/*
	300	* Clear the VL bit in the seconds register in case
	301	* the time has not been set already (which would
	302	* have cleared it). This does not really matter
	303	* because of the cached voltage_low value but do it
	304	* anyway for consistency.
	305	*/
	306	if (pcf8563_get_datetime(to_i2c_client(dev), &tm))
	307	pcf8563_set_datetime(to_i2c_client(dev), &tm);
	308
	309	/* Clear the cached value. */
	310	pcf8563->voltage_low = 0;
	311
	312	return 0;
	313	default:
	314	return -ENOIOCTLCMD;
	315	}
	316	}
	317	#else
	318	#define pcf8563_rtc_ioctl NULL
	319	#endif
	320
b5a82d62 AZ	321	static int pcf8563_rtc_read_time(struct device dev, struct rtc_time tm)
	322	{
	323	return pcf8563_get_datetime(to_i2c_client(dev), tm);
	324	}
	325
	326	static int pcf8563_rtc_set_time(struct device dev, struct rtc_time tm)
	327	{
	328	return pcf8563_set_datetime(to_i2c_client(dev), tm);
	329	}
	330
ede3e9d4 VD	331	static int pcf8563_rtc_read_alarm(struct device dev, struct rtc_wkalrm tm)
	332	{
	333	struct i2c_client *client = to_i2c_client(dev);
	334	unsigned char buf[4];
	335	int err;
	336
	337	err = pcf8563_read_block_data(client, PCF8563_REG_AMN, 4, buf);
	338	if (err)
	339	return err;
	340
	341	dev_dbg(&client->dev,
	342	"%s: raw data is min=%02x, hr=%02x, mday=%02x, wday=%02x\n",
	343	__func__, buf[0], buf[1], buf[2], buf[3]);
	344
	345	tm->time.tm_min = bcd2bin(buf[0] & 0x7F);
c7aef4f8 JK	346	tm->time.tm_hour = bcd2bin(buf[1] & 0x3F);
c7aef4f8 JK	347	tm->time.tm_mday = bcd2bin(buf[2] & 0x3F);
ede3e9d4 VD	348	tm->time.tm_wday = bcd2bin(buf[3] & 0x7);
	349	tm->time.tm_mon = -1;
	350	tm->time.tm_year = -1;
	351	tm->time.tm_yday = -1;
	352	tm->time.tm_isdst = -1;
	353
	354	err = pcf8563_get_alarm_mode(client, &tm->enabled, &tm->pending);
	355	if (err < 0)
	356	return err;
	357
	358	dev_dbg(&client->dev, "%s: tm is mins=%d, hours=%d, mday=%d, wday=%d,"
	359	" enabled=%d, pending=%d\n", __func__, tm->time.tm_min,
	360	tm->time.tm_hour, tm->time.tm_mday, tm->time.tm_wday,
	361	tm->enabled, tm->pending);
	362
	363	return 0;
	364	}
	365
	366	static int pcf8563_rtc_set_alarm(struct device dev, struct rtc_wkalrm tm)
	367	{
	368	struct i2c_client *client = to_i2c_client(dev);
	369	unsigned char buf[4];
	370	int err;
599cda55 JK	371	unsigned long alarm_time;
	372
	373	/* The alarm has no seconds, round up to nearest minute */
	374	if (tm->time.tm_sec) {
	375	rtc_tm_to_time(&tm->time, &alarm_time);
	376	alarm_time += 60-tm->time.tm_sec;
	377	rtc_time_to_tm(alarm_time, &tm->time);
	378	}
ede3e9d4 VD	379
	380	dev_dbg(dev, "%s, min=%d hour=%d wday=%d mday=%d "
	381	"enabled=%d pending=%d\n", __func__,
	382	tm->time.tm_min, tm->time.tm_hour, tm->time.tm_wday,
	383	tm->time.tm_mday, tm->enabled, tm->pending);
	384
	385	buf[0] = bin2bcd(tm->time.tm_min);
	386	buf[1] = bin2bcd(tm->time.tm_hour);
	387	buf[2] = bin2bcd(tm->time.tm_mday);
	388	buf[3] = tm->time.tm_wday & 0x07;
	389
	390	err = pcf8563_write_block_data(client, PCF8563_REG_AMN, 4, buf);
	391	if (err)
	392	return err;
	393
	394	return pcf8563_set_alarm_mode(client, 1);
	395	}
	396
	397	static int pcf8563_irq_enable(struct device *dev, unsigned int enabled)
	398	{
a45d528a	399	dev_dbg(dev, "%s: en=%d\n", __func__, enabled);
ede3e9d4 VD	400	return pcf8563_set_alarm_mode(to_i2c_client(dev), !!enabled);
	401	}
	402
ff8371ac	403	static const struct rtc_class_ops pcf8563_rtc_ops = {
0f20b767	404	.ioctl = pcf8563_rtc_ioctl,
b5a82d62 AZ	405	.read_time = pcf8563_rtc_read_time,
b5a82d62 AZ	406	.set_time = pcf8563_rtc_set_time,
ede3e9d4 VD	407	.read_alarm = pcf8563_rtc_read_alarm,
	408	.set_alarm = pcf8563_rtc_set_alarm,
	409	.alarm_irq_enable = pcf8563_irq_enable,
b5a82d62 AZ	410	};
b5a82d62 AZ	411
d2653e92 JD	412	static int pcf8563_probe(struct i2c_client *client,
d2653e92 JD	413	const struct i2c_device_id *id)
b5a82d62	414	{
cbb94502	415	struct pcf8563 *pcf8563;
ede3e9d4	416	int err;
ff0bc501	417	unsigned char buf;
a45d528a	418	unsigned char alm_pending;
b5a82d62	419
e5fc9cc0	420	dev_dbg(&client->dev, "%s\n", __func__);
b5a82d62	421
e5fc9cc0 AZ	422	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
e5fc9cc0 AZ	423	return -ENODEV;
b5a82d62	424
d6fbdc34 JH	425	pcf8563 = devm_kzalloc(&client->dev, sizeof(struct pcf8563),
d6fbdc34 JH	426	GFP_KERNEL);
e5fc9cc0 AZ	427	if (!pcf8563)
e5fc9cc0 AZ	428	return -ENOMEM;
b5a82d62	429
b5a82d62 AZ	430	dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");
b5a82d62 AZ	431
b74d2caa	432	i2c_set_clientdata(client, pcf8563);
ede3e9d4 VD	433	pcf8563->client = client;
ede3e9d4 VD	434	device_set_wakeup_capable(&client->dev, 1);
b74d2caa	435
ff0bc501 JK	436	/* Set timer to lowest frequency to save power (ref Haoyu datasheet) */
	437	buf = PCF8563_TMRC_1_60;
	438	err = pcf8563_write_block_data(client, PCF8563_REG_TMRC, 1, &buf);
	439	if (err < 0) {
	440	dev_err(&client->dev, "%s: write error\n", __func__);
	441	return err;
	442	}
	443
a45d528a JK	444	err = pcf8563_get_alarm_mode(client, NULL, &alm_pending);
	445	if (err < 0) {
	446	dev_err(&client->dev, "%s: read error\n", __func__);
	447	return err;
	448	}
	449	if (alm_pending)
	450	pcf8563_set_alarm_mode(client, 0);
	451
d6fbdc34 JH	452	pcf8563->rtc = devm_rtc_device_register(&client->dev,
	453	pcf8563_driver.driver.name,
	454	&pcf8563_rtc_ops, THIS_MODULE);
b5a82d62	455
ede3e9d4 VD	456	if (IS_ERR(pcf8563->rtc))
	457	return PTR_ERR(pcf8563->rtc);
	458
	459	if (client->irq > 0) {
	460	err = devm_request_threaded_irq(&client->dev, client->irq,
	461	NULL, pcf8563_irq,
	462	IRQF_SHARED\|IRQF_ONESHOT\|IRQF_TRIGGER_FALLING,
	463	pcf8563->rtc->name, client);
	464	if (err) {
	465	dev_err(&client->dev, "unable to request IRQ %d\n",
	466	client->irq);
	467	return err;
	468	}
	469
	470	}
	471
599cda55 JK	472	/* the pcf8563 alarm only supports a minute accuracy */
	473	pcf8563->rtc->uie_unsupported = 1;
	474
ede3e9d4	475	return 0;
b5a82d62 AZ	476	}
b5a82d62 AZ	477
3760f736 JD	478	static const struct i2c_device_id pcf8563_id[] = {
3760f736 JD	479	{ "pcf8563", 0 },
8ea9212c	480	{ "rtc8564", 0 },
3760f736 JD	481	{ }
	482	};
	483	MODULE_DEVICE_TABLE(i2c, pcf8563_id);
	484
8dccaf06	485	#ifdef CONFIG_OF
5a167f45	486	static const struct of_device_id pcf8563_of_match[] = {
8dccaf06 NB	487	{ .compatible = "nxp,pcf8563" },
	488	{}
	489	};
	490	MODULE_DEVICE_TABLE(of, pcf8563_of_match);
	491	#endif
	492
e5fc9cc0 AZ	493	static struct i2c_driver pcf8563_driver = {
	494	.driver = {
	495	.name = "rtc-pcf8563",
0a25bf40	496	.owner = THIS_MODULE,
8dccaf06	497	.of_match_table = of_match_ptr(pcf8563_of_match),
e5fc9cc0 AZ	498	},
e5fc9cc0 AZ	499	.probe = pcf8563_probe,
3760f736	500	.id_table = pcf8563_id,
e5fc9cc0 AZ	501	};
e5fc9cc0 AZ	502
0abc9201	503	module_i2c_driver(pcf8563_driver);
b5a82d62 AZ	504
	505	MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
	506	MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver");
	507	MODULE_LICENSE("GPL");
	508	MODULE_VERSION(DRV_VERSION);