[linux-2.6-block.git] / drivers / rtc / rtc-abx80x.c

/*
 * A driver for the I2C members of the Abracon AB x8xx RTC family,
 * and compatible: AB 1805 and AB 0805
 *
 * Copyright 2014-2015 Macq S.A.
 *
 * Author: Philippe De Muyter <phdm@macqel.be>
 * Author: Alexandre Belloni <alexandre.belloni@free-electrons.com>
 *
 * 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/bcd.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/rtc.h>

#define ABX8XX_REG_HTH		0x00
#define ABX8XX_REG_SC		0x01
#define ABX8XX_REG_MN		0x02
#define ABX8XX_REG_HR		0x03
#define ABX8XX_REG_DA		0x04
#define ABX8XX_REG_MO		0x05
#define ABX8XX_REG_YR		0x06
#define ABX8XX_REG_WD		0x07

#define ABX8XX_REG_AHTH		0x08
#define ABX8XX_REG_ASC		0x09
#define ABX8XX_REG_AMN		0x0a
#define ABX8XX_REG_AHR		0x0b
#define ABX8XX_REG_ADA		0x0c
#define ABX8XX_REG_AMO		0x0d
#define ABX8XX_REG_AWD		0x0e

#define ABX8XX_REG_STATUS	0x0f
#define ABX8XX_STATUS_AF	BIT(2)

#define ABX8XX_REG_CTRL1	0x10
#define ABX8XX_CTRL_WRITE	BIT(0)
#define ABX8XX_CTRL_ARST	BIT(2)
#define ABX8XX_CTRL_12_24	BIT(6)

#define ABX8XX_REG_IRQ		0x12
#define ABX8XX_IRQ_AIE		BIT(2)
#define ABX8XX_IRQ_IM_1_4	(0x3 << 5)

#define ABX8XX_REG_CD_TIMER_CTL	0x18

#define ABX8XX_REG_CFG_KEY	0x1f
#define ABX8XX_CFG_KEY_MISC	0x9d

#define ABX8XX_REG_ID0		0x28

#define ABX8XX_REG_TRICKLE	0x20
#define ABX8XX_TRICKLE_CHARGE_ENABLE	0xa0
#define ABX8XX_TRICKLE_STANDARD_DIODE	0x8
#define ABX8XX_TRICKLE_SCHOTTKY_DIODE	0x4

static u8 trickle_resistors[] = {0, 3, 6, 11};

enum abx80x_chip {AB0801, AB0803, AB0804, AB0805,
	AB1801, AB1803, AB1804, AB1805, ABX80X};

struct abx80x_cap {
	u16 pn;
	bool has_tc;
};

static struct abx80x_cap abx80x_caps[] = {
	[AB0801] = {.pn = 0x0801},
	[AB0803] = {.pn = 0x0803},
	[AB0804] = {.pn = 0x0804, .has_tc = true},
	[AB0805] = {.pn = 0x0805, .has_tc = true},
	[AB1801] = {.pn = 0x1801},
	[AB1803] = {.pn = 0x1803},
	[AB1804] = {.pn = 0x1804, .has_tc = true},
	[AB1805] = {.pn = 0x1805, .has_tc = true},
	[ABX80X] = {.pn = 0}
};

static int abx80x_enable_trickle_charger(struct i2c_client *client,
					 u8 trickle_cfg)
{
	int err;

	/*
	 * Write the configuration key register to enable access to the Trickle
	 * register
	 */
	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY,
					ABX8XX_CFG_KEY_MISC);
	if (err < 0) {
		dev_err(&client->dev, "Unable to write configuration key\n");
		return -EIO;
	}

	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE,
					ABX8XX_TRICKLE_CHARGE_ENABLE |
					trickle_cfg);
	if (err < 0) {
		dev_err(&client->dev, "Unable to write trickle register\n");
		return -EIO;
	}

	return 0;
}

static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned char buf[8];
	int err;

	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH,
					    sizeof(buf), buf);
	if (err < 0) {
		dev_err(&client->dev, "Unable to read date\n");
		return -EIO;
	}

	tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F);
	tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F);
	tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F);
	tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7;
	tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F);
	tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1;
	tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100;

	err = rtc_valid_tm(tm);
	if (err < 0)
		dev_err(&client->dev, "retrieved date/time is not valid.\n");

	return err;
}

static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned char buf[8];
	int err;

	if (tm->tm_year < 100)
		return -EINVAL;

	buf[ABX8XX_REG_HTH] = 0;
	buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec);
	buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min);
	buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour);
	buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday);
	buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1);
	buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100);
	buf[ABX8XX_REG_WD] = tm->tm_wday;

	err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH,
					     sizeof(buf), buf);
	if (err < 0) {
		dev_err(&client->dev, "Unable to write to date registers\n");
		return -EIO;
	}

	return 0;
}

static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)
{
	struct i2c_client *client = dev_id;
	struct rtc_device *rtc = i2c_get_clientdata(client);
	int status;

	status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
	if (status < 0)
		return IRQ_NONE;

	if (status & ABX8XX_STATUS_AF)
		rtc_update_irq(rtc, 1, RTC_AF | RTC_IRQF);

	i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);

	return IRQ_HANDLED;
}

static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned char buf[7];

	int irq_mask, err;

	if (client->irq <= 0)
		return -EINVAL;

	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC,
					    sizeof(buf), buf);
	if (err)
		return err;

	irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ);
	if (irq_mask < 0)
		return irq_mask;

	t->time.tm_sec = bcd2bin(buf[0] & 0x7F);
	t->time.tm_min = bcd2bin(buf[1] & 0x7F);
	t->time.tm_hour = bcd2bin(buf[2] & 0x3F);
	t->time.tm_mday = bcd2bin(buf[3] & 0x3F);
	t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1;
	t->time.tm_wday = buf[5] & 0x7;

	t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE);
	t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled;

	return err;
}

static int abx80x_set_alarm(struct device *dev, struct rtc_wkalrm *t)
{
	struct i2c_client *client = to_i2c_client(dev);
	u8 alarm[6];
	int err;

	if (client->irq <= 0)
		return -EINVAL;

	alarm[0] = 0x0;
	alarm[1] = bin2bcd(t->time.tm_sec);
	alarm[2] = bin2bcd(t->time.tm_min);
	alarm[3] = bin2bcd(t->time.tm_hour);
	alarm[4] = bin2bcd(t->time.tm_mday);
	alarm[5] = bin2bcd(t->time.tm_mon + 1);

	err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH,
					     sizeof(alarm), alarm);
	if (err < 0) {
		dev_err(&client->dev, "Unable to write alarm registers\n");
		return -EIO;
	}

	if (t->enabled) {
		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
						(ABX8XX_IRQ_IM_1_4 |
						 ABX8XX_IRQ_AIE));
		if (err)
			return err;
	}

	return 0;
}

static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
	struct i2c_client *client = to_i2c_client(dev);
	int err;

	if (enabled)
		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
						(ABX8XX_IRQ_IM_1_4 |
						 ABX8XX_IRQ_AIE));
	else
		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
						ABX8XX_IRQ_IM_1_4);
	return err;
}

static const struct rtc_class_ops abx80x_rtc_ops = {
	.read_time	= abx80x_rtc_read_time,
	.set_time	= abx80x_rtc_set_time,
	.read_alarm	= abx80x_read_alarm,
	.set_alarm	= abx80x_set_alarm,
	.alarm_irq_enable = abx80x_alarm_irq_enable,
};

static int abx80x_dt_trickle_cfg(struct device_node *np)
{
	const char *diode;
	int trickle_cfg = 0;
	int i, ret;
	u32 tmp;

	ret = of_property_read_string(np, "abracon,tc-diode", &diode);
	if (ret)
		return ret;

	if (!strcmp(diode, "standard"))
		trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE;
	else if (!strcmp(diode, "schottky"))
		trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE;
	else
		return -EINVAL;

	ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp);
	if (ret)
		return ret;

	for (i = 0; i < sizeof(trickle_resistors); i++)
		if (trickle_resistors[i] == tmp)
			break;

	if (i == sizeof(trickle_resistors))
		return -EINVAL;

	return (trickle_cfg | i);
}

static int abx80x_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct device_node *np = client->dev.of_node;
	struct rtc_device *rtc;
	int i, data, err, trickle_cfg = -EINVAL;
	char buf[7];
	unsigned int part = id->driver_data;
	unsigned int partnumber;
	unsigned int majrev, minrev;
	unsigned int lot;
	unsigned int wafer;
	unsigned int uid;

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

	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0,
					    sizeof(buf), buf);
	if (err < 0) {
		dev_err(&client->dev, "Unable to read partnumber\n");
		return -EIO;
	}

	partnumber = (buf[0] << 8) | buf[1];
	majrev = buf[2] >> 3;
	minrev = buf[2] & 0x7;
	lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3];
	uid = ((buf[4] & 0x7f) << 8) | buf[5];
	wafer = (buf[6] & 0x7c) >> 2;
	dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n",
		 partnumber, majrev, minrev, lot, wafer, uid);

	data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1);
	if (data < 0) {
		dev_err(&client->dev, "Unable to read control register\n");
		return -EIO;
	}

	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1,
					((data & ~(ABX8XX_CTRL_12_24 |
						   ABX8XX_CTRL_ARST)) |
					 ABX8XX_CTRL_WRITE));
	if (err < 0) {
		dev_err(&client->dev, "Unable to write control register\n");
		return -EIO;
	}

	/* part autodetection */
	if (part == ABX80X) {
		for (i = 0; abx80x_caps[i].pn; i++)
			if (partnumber == abx80x_caps[i].pn)
				break;
		if (abx80x_caps[i].pn == 0) {
			dev_err(&client->dev, "Unknown part: %04x\n",
				partnumber);
			return -EINVAL;
		}
		part = i;
	}

	if (partnumber != abx80x_caps[part].pn) {
		dev_err(&client->dev, "partnumber mismatch %04x != %04x\n",
			partnumber, abx80x_caps[part].pn);
		return -EINVAL;
	}

	if (np && abx80x_caps[part].has_tc)
		trickle_cfg = abx80x_dt_trickle_cfg(np);

	if (trickle_cfg > 0) {
		dev_info(&client->dev, "Enabling trickle charger: %02x\n",
			 trickle_cfg);
		abx80x_enable_trickle_charger(client, trickle_cfg);
	}

	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL,
					BIT(2));
	if (err)
		return err;

	rtc = devm_rtc_device_register(&client->dev, "abx8xx",
				       &abx80x_rtc_ops, THIS_MODULE);

	if (IS_ERR(rtc))
		return PTR_ERR(rtc);

	i2c_set_clientdata(client, rtc);

	if (client->irq > 0) {
		dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
		err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
						abx80x_handle_irq,
						IRQF_SHARED | IRQF_ONESHOT,
						"abx8xx",
						client);
		if (err) {
			dev_err(&client->dev, "unable to request IRQ, alarms disabled\n");
			client->irq = 0;
		}
	}

	return 0;
}

static int abx80x_remove(struct i2c_client *client)
{
	return 0;
}

static const struct i2c_device_id abx80x_id[] = {
	{ "abx80x", ABX80X },
	{ "ab0801", AB0801 },
	{ "ab0803", AB0803 },
	{ "ab0804", AB0804 },
	{ "ab0805", AB0805 },
	{ "ab1801", AB1801 },
	{ "ab1803", AB1803 },
	{ "ab1804", AB1804 },
	{ "ab1805", AB1805 },
	{ "rv1805", AB1805 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, abx80x_id);

static struct i2c_driver abx80x_driver = {
	.driver		= {
		.name	= "rtc-abx80x",
	},
	.probe		= abx80x_probe,
	.remove		= abx80x_remove,
	.id_table	= abx80x_id,
};

module_i2c_driver(abx80x_driver);

MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>");
MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
MODULE_DESCRIPTION("Abracon ABX80X RTC driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
4d61ff6b PDM	1	/*
	2	* A driver for the I2C members of the Abracon AB x8xx RTC family,
	3	* and compatible: AB 1805 and AB 0805
	4	*
	5	* Copyright 2014-2015 Macq S.A.
	6	*
	7	* Author: Philippe De Muyter <phdm@macqel.be>
	8	* Author: Alexandre Belloni <alexandre.belloni@free-electrons.com>
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License version 2 as
	12	* published by the Free Software Foundation.
	13	*
	14	*/
	15
	16	#include <linux/bcd.h>
	17	#include <linux/i2c.h>
	18	#include <linux/module.h>
	19	#include <linux/rtc.h>
	20
	21	#define ABX8XX_REG_HTH 0x00
	22	#define ABX8XX_REG_SC 0x01
	23	#define ABX8XX_REG_MN 0x02
	24	#define ABX8XX_REG_HR 0x03
	25	#define ABX8XX_REG_DA 0x04
	26	#define ABX8XX_REG_MO 0x05
	27	#define ABX8XX_REG_YR 0x06
	28	#define ABX8XX_REG_WD 0x07
	29
718a820a AB	30	#define ABX8XX_REG_AHTH 0x08
	31	#define ABX8XX_REG_ASC 0x09
	32	#define ABX8XX_REG_AMN 0x0a
	33	#define ABX8XX_REG_AHR 0x0b
	34	#define ABX8XX_REG_ADA 0x0c
	35	#define ABX8XX_REG_AMO 0x0d
	36	#define ABX8XX_REG_AWD 0x0e
	37
	38	#define ABX8XX_REG_STATUS 0x0f
	39	#define ABX8XX_STATUS_AF BIT(2)
	40
4d61ff6b	41	#define ABX8XX_REG_CTRL1 0x10
5f1b2f77	42	#define ABX8XX_CTRL_WRITE BIT(0)
718a820a	43	#define ABX8XX_CTRL_ARST BIT(2)
4d61ff6b PDM	44	#define ABX8XX_CTRL_12_24 BIT(6)
4d61ff6b PDM	45
718a820a AB	46	#define ABX8XX_REG_IRQ 0x12
	47	#define ABX8XX_IRQ_AIE BIT(2)
	48	#define ABX8XX_IRQ_IM_1_4 (0x3 << 5)
	49
	50	#define ABX8XX_REG_CD_TIMER_CTL 0x18
	51
4d61ff6b PDM	52	#define ABX8XX_REG_CFG_KEY 0x1f
	53	#define ABX8XX_CFG_KEY_MISC 0x9d
	54
	55	#define ABX8XX_REG_ID0 0x28
	56
	57	#define ABX8XX_REG_TRICKLE 0x20
	58	#define ABX8XX_TRICKLE_CHARGE_ENABLE 0xa0
	59	#define ABX8XX_TRICKLE_STANDARD_DIODE 0x8
	60	#define ABX8XX_TRICKLE_SCHOTTKY_DIODE 0x4
	61
	62	static u8 trickle_resistors[] = {0, 3, 6, 11};
	63
	64	enum abx80x_chip {AB0801, AB0803, AB0804, AB0805,
	65	AB1801, AB1803, AB1804, AB1805, ABX80X};
	66
	67	struct abx80x_cap {
	68	u16 pn;
	69	bool has_tc;
	70	};
	71
	72	static struct abx80x_cap abx80x_caps[] = {
	73	[AB0801] = {.pn = 0x0801},
	74	[AB0803] = {.pn = 0x0803},
	75	[AB0804] = {.pn = 0x0804, .has_tc = true},
	76	[AB0805] = {.pn = 0x0805, .has_tc = true},
	77	[AB1801] = {.pn = 0x1801},
	78	[AB1803] = {.pn = 0x1803},
	79	[AB1804] = {.pn = 0x1804, .has_tc = true},
	80	[AB1805] = {.pn = 0x1805, .has_tc = true},
	81	[ABX80X] = {.pn = 0}
	82	};
	83
4d61ff6b PDM	84	static int abx80x_enable_trickle_charger(struct i2c_client *client,
	85	u8 trickle_cfg)
	86	{
	87	int err;
	88
	89	/*
	90	* Write the configuration key register to enable access to the Trickle
	91	* register
	92	*/
	93	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY,
	94	ABX8XX_CFG_KEY_MISC);
	95	if (err < 0) {
	96	dev_err(&client->dev, "Unable to write configuration key\n");
	97	return -EIO;
	98	}
	99
	100	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE,
	101	ABX8XX_TRICKLE_CHARGE_ENABLE \|
	102	trickle_cfg);
	103	if (err < 0) {
	104	dev_err(&client->dev, "Unable to write trickle register\n");
	105	return -EIO;
	106	}
	107
	108	return 0;
	109	}
	110
	111	static int abx80x_rtc_read_time(struct device dev, struct rtc_time tm)
	112	{
	113	struct i2c_client *client = to_i2c_client(dev);
	114	unsigned char buf[8];
	115	int err;
	116
	117	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH,
	118	sizeof(buf), buf);
	119	if (err < 0) {
	120	dev_err(&client->dev, "Unable to read date\n");
	121	return -EIO;
	122	}
	123
	124	tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F);
	125	tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F);
	126	tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F);
	127	tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7;
	128	tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F);
	129	tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1;
	130	tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100;
	131
	132	err = rtc_valid_tm(tm);
	133	if (err < 0)
	134	dev_err(&client->dev, "retrieved date/time is not valid.\n");
	135
	136	return err;
	137	}
	138
	139	static int abx80x_rtc_set_time(struct device dev, struct rtc_time tm)
	140	{
	141	struct i2c_client *client = to_i2c_client(dev);
	142	unsigned char buf[8];
	143	int err;
	144
	145	if (tm->tm_year < 100)
	146	return -EINVAL;
	147
148	buf[ABX8XX_REG_HTH] = 0;
149	buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec);
150	buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min);
151	buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour);
152	buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday);
153	buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1);
154	buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100);
155	buf[ABX8XX_REG_WD] = tm->tm_wday;
156
157	err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH,
158	sizeof(buf), buf);
159	if (err < 0) {
160	dev_err(&client->dev, "Unable to write to date registers\n");
161	return -EIO;
162	}
163
164	return 0;
165	}
166
718a820a AB	167	static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)
	168	{
	169	struct i2c_client *client = dev_id;
	170	struct rtc_device *rtc = i2c_get_clientdata(client);
	171	int status;
	172
	173	status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
	174	if (status < 0)
	175	return IRQ_NONE;
	176
	177	if (status & ABX8XX_STATUS_AF)
	178	rtc_update_irq(rtc, 1, RTC_AF \| RTC_IRQF);
	179
	180	i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);
	181
	182	return IRQ_HANDLED;
	183	}
	184
	185	static int abx80x_read_alarm(struct device dev, struct rtc_wkalrm t)
	186	{
	187	struct i2c_client *client = to_i2c_client(dev);
	188	unsigned char buf[7];
	189
	190	int irq_mask, err;
	191
	192	if (client->irq <= 0)
	193	return -EINVAL;
	194
	195	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC,
	196	sizeof(buf), buf);
	197	if (err)
	198	return err;
	199
	200	irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ);
	201	if (irq_mask < 0)
	202	return irq_mask;
	203
	204	t->time.tm_sec = bcd2bin(buf[0] & 0x7F);
	205	t->time.tm_min = bcd2bin(buf[1] & 0x7F);
	206	t->time.tm_hour = bcd2bin(buf[2] & 0x3F);
	207	t->time.tm_mday = bcd2bin(buf[3] & 0x3F);
	208	t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1;
	209	t->time.tm_wday = buf[5] & 0x7;
	210
	211	t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE);
	212	t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled;
	213
	214	return err;
	215	}
	216
	217	static int abx80x_set_alarm(struct device dev, struct rtc_wkalrm t)
	218	{
	219	struct i2c_client *client = to_i2c_client(dev);
	220	u8 alarm[6];
	221	int err;
	222
	223	if (client->irq <= 0)
	224	return -EINVAL;
	225
	226	alarm[0] = 0x0;
	227	alarm[1] = bin2bcd(t->time.tm_sec);
	228	alarm[2] = bin2bcd(t->time.tm_min);
	229	alarm[3] = bin2bcd(t->time.tm_hour);
	230	alarm[4] = bin2bcd(t->time.tm_mday);
231	alarm[5] = bin2bcd(t->time.tm_mon + 1);
232
233	err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH,
234	sizeof(alarm), alarm);
235	if (err < 0) {
236	dev_err(&client->dev, "Unable to write alarm registers\n");
237	return -EIO;
238	}
239
240	if (t->enabled) {
241	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
242	(ABX8XX_IRQ_IM_1_4 \|
243	ABX8XX_IRQ_AIE));
244	if (err)
245	return err;
246	}
247
248	return 0;
249	}
250
251	static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled)
252	{
253	struct i2c_client *client = to_i2c_client(dev);
254	int err;
255
256	if (enabled)
257	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
258	(ABX8XX_IRQ_IM_1_4 \|
259	ABX8XX_IRQ_AIE));
260	else
261	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
262	ABX8XX_IRQ_IM_1_4);
263	return err;
264	}
265
4d61ff6b PDM	266	static const struct rtc_class_ops abx80x_rtc_ops = {
	267	.read_time = abx80x_rtc_read_time,
	268	.set_time = abx80x_rtc_set_time,
718a820a AB	269	.read_alarm = abx80x_read_alarm,
	270	.set_alarm = abx80x_set_alarm,
	271	.alarm_irq_enable = abx80x_alarm_irq_enable,
4d61ff6b PDM	272	};
	273
	274	static int abx80x_dt_trickle_cfg(struct device_node *np)
	275	{
	276	const char *diode;
	277	int trickle_cfg = 0;
	278	int i, ret;
	279	u32 tmp;
	280
	281	ret = of_property_read_string(np, "abracon,tc-diode", &diode);
	282	if (ret)
	283	return ret;
	284
	285	if (!strcmp(diode, "standard"))
	286	trickle_cfg \|= ABX8XX_TRICKLE_STANDARD_DIODE;
	287	else if (!strcmp(diode, "schottky"))
	288	trickle_cfg \|= ABX8XX_TRICKLE_SCHOTTKY_DIODE;
	289	else
	290	return -EINVAL;
	291
	292	ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp);
	293	if (ret)
	294	return ret;
	295
	296	for (i = 0; i < sizeof(trickle_resistors); i++)
	297	if (trickle_resistors[i] == tmp)
	298	break;
	299
	300	if (i == sizeof(trickle_resistors))
	301	return -EINVAL;
	302
	303	return (trickle_cfg \| i);
	304	}
	305
	306	static int abx80x_probe(struct i2c_client *client,
	307	const struct i2c_device_id *id)
	308	{
	309	struct device_node *np = client->dev.of_node;
	310	struct rtc_device *rtc;
	311	int i, data, err, trickle_cfg = -EINVAL;
	312	char buf[7];
	313	unsigned int part = id->driver_data;
	314	unsigned int partnumber;
	315	unsigned int majrev, minrev;
	316	unsigned int lot;
	317	unsigned int wafer;
	318	unsigned int uid;
	319
	320	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
	321	return -ENODEV;
	322
	323	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0,
	324	sizeof(buf), buf);
	325	if (err < 0) {
	326	dev_err(&client->dev, "Unable to read partnumber\n");
	327	return -EIO;
	328	}
	329
	330	partnumber = (buf[0] << 8) \| buf[1];
	331	majrev = buf[2] >> 3;
	332	minrev = buf[2] & 0x7;
	333	lot = ((buf[4] & 0x80) << 2) \| ((buf[6] & 0x80) << 1) \| buf[3];
	334	uid = ((buf[4] & 0x7f) << 8) \| buf[5];
	335	wafer = (buf[6] & 0x7c) >> 2;
336	dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n",
337	partnumber, majrev, minrev, lot, wafer, uid);
338
339	data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1);
340	if (data < 0) {
341	dev_err(&client->dev, "Unable to read control register\n");
342	return -EIO;
343	}
344
345	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1,
718a820a AB	346	((data & ~(ABX8XX_CTRL_12_24 \|
718a820a AB	347	ABX8XX_CTRL_ARST)) \|
4d61ff6b PDM	348	ABX8XX_CTRL_WRITE));
	349	if (err < 0) {
	350	dev_err(&client->dev, "Unable to write control register\n");
	351	return -EIO;
	352	}
	353
	354	/* part autodetection */
	355	if (part == ABX80X) {
	356	for (i = 0; abx80x_caps[i].pn; i++)
	357	if (partnumber == abx80x_caps[i].pn)
	358	break;
	359	if (abx80x_caps[i].pn == 0) {
	360	dev_err(&client->dev, "Unknown part: %04x\n",
	361	partnumber);
	362	return -EINVAL;
	363	}
	364	part = i;
	365	}
	366
	367	if (partnumber != abx80x_caps[part].pn) {
	368	dev_err(&client->dev, "partnumber mismatch %04x != %04x\n",
	369	partnumber, abx80x_caps[part].pn);
	370	return -EINVAL;
	371	}
	372
	373	if (np && abx80x_caps[part].has_tc)
	374	trickle_cfg = abx80x_dt_trickle_cfg(np);
	375
	376	if (trickle_cfg > 0) {
	377	dev_info(&client->dev, "Enabling trickle charger: %02x\n",
	378	trickle_cfg);
	379	abx80x_enable_trickle_charger(client, trickle_cfg);
	380	}
	381
718a820a AB	382	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL,
	383	BIT(2));
	384	if (err)
	385	return err;
	386
	387	rtc = devm_rtc_device_register(&client->dev, "abx8xx",
4d61ff6b PDM	388	&abx80x_rtc_ops, THIS_MODULE);
	389
	390	if (IS_ERR(rtc))
	391	return PTR_ERR(rtc);
	392
	393	i2c_set_clientdata(client, rtc);
	394
718a820a AB	395	if (client->irq > 0) {
	396	dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
	397	err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
	398	abx80x_handle_irq,
	399	IRQF_SHARED \| IRQF_ONESHOT,
	400	"abx8xx",
	401	client);
	402	if (err) {
	403	dev_err(&client->dev, "unable to request IRQ, alarms disabled\n");
	404	client->irq = 0;
	405	}
	406	}
	407
4d61ff6b PDM	408	return 0;
	409	}
	410
	411	static int abx80x_remove(struct i2c_client *client)
	412	{
	413	return 0;
	414	}
	415
	416	static const struct i2c_device_id abx80x_id[] = {
	417	{ "abx80x", ABX80X },
	418	{ "ab0801", AB0801 },
	419	{ "ab0803", AB0803 },
	420	{ "ab0804", AB0804 },
	421	{ "ab0805", AB0805 },
	422	{ "ab1801", AB1801 },
	423	{ "ab1803", AB1803 },
	424	{ "ab1804", AB1804 },
	425	{ "ab1805", AB1805 },
fca733a1	426	{ "rv1805", AB1805 },
4d61ff6b PDM	427	{ }
	428	};
	429	MODULE_DEVICE_TABLE(i2c, abx80x_id);
	430
	431	static struct i2c_driver abx80x_driver = {
	432	.driver = {
	433	.name = "rtc-abx80x",
	434	},
	435	.probe = abx80x_probe,
	436	.remove = abx80x_remove,
	437	.id_table = abx80x_id,
	438	};
	439
	440	module_i2c_driver(abx80x_driver);
	441
	442	MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>");
	443	MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
	444	MODULE_DESCRIPTION("Abracon ABX80X RTC driver");
	445	MODULE_LICENSE("GPL v2");