[mirror_ubuntu-bionic-kernel.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_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_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;

	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] & 0x7F);
	tm->time.tm_mday = bcd2bin(buf[2] & 0x1F);
	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;

	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)
{
	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;

	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);

	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;
		}

	}

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