[linux-2.6-block.git] / drivers / rtc / rtc-isl12057.c

/*
 * rtc-isl12057 - Driver for Intersil ISL12057 I2C Real Time Clock
 *
 * Copyright (C) 2013, Arnaud EBALARD <arno@natisbad.org>
 *
 * This work is largely based on Intersil ISL1208 driver developed by
 * Hebert Valerio Riedel <hvr@gnu.org>.
 *
 * Detailed datasheet on which this development is based is available here:
 *
 *  http://natisbad.org/NAS2/refs/ISL12057.pdf
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/rtc.h>
#include <linux/i2c.h>
#include <linux/bcd.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/regmap.h>

#define DRV_NAME "rtc-isl12057"

/* RTC section */
#define ISL12057_REG_RTC_SC	0x00	/* Seconds */
#define ISL12057_REG_RTC_MN	0x01	/* Minutes */
#define ISL12057_REG_RTC_HR	0x02	/* Hours */
#define ISL12057_REG_RTC_HR_PM	BIT(5)	/* AM/PM bit in 12h format */
#define ISL12057_REG_RTC_HR_MIL BIT(6)	/* 24h/12h format */
#define ISL12057_REG_RTC_DW	0x03	/* Day of the Week */
#define ISL12057_REG_RTC_DT	0x04	/* Date */
#define ISL12057_REG_RTC_MO	0x05	/* Month */
#define ISL12057_REG_RTC_MO_CEN	BIT(7)	/* Century bit */
#define ISL12057_REG_RTC_YR	0x06	/* Year */
#define ISL12057_RTC_SEC_LEN	7

/* Alarm 1 section */
#define ISL12057_REG_A1_SC	0x07	/* Alarm 1 Seconds */
#define ISL12057_REG_A1_MN	0x08	/* Alarm 1 Minutes */
#define ISL12057_REG_A1_HR	0x09	/* Alarm 1 Hours */
#define ISL12057_REG_A1_HR_PM	BIT(5)	/* AM/PM bit in 12h format */
#define ISL12057_REG_A1_HR_MIL	BIT(6)	/* 24h/12h format */
#define ISL12057_REG_A1_DWDT	0x0A	/* Alarm 1 Date / Day of the week */
#define ISL12057_REG_A1_DWDT_B	BIT(6)	/* DW / DT selection bit */
#define ISL12057_A1_SEC_LEN	4

/* Alarm 2 section */
#define ISL12057_REG_A2_MN	0x0B	/* Alarm 2 Minutes */
#define ISL12057_REG_A2_HR	0x0C	/* Alarm 2 Hours */
#define ISL12057_REG_A2_DWDT	0x0D	/* Alarm 2 Date / Day of the week */
#define ISL12057_A2_SEC_LEN	3

/* Control/Status registers */
#define ISL12057_REG_INT	0x0E
#define ISL12057_REG_INT_A1IE	BIT(0)	/* Alarm 1 interrupt enable bit */
#define ISL12057_REG_INT_A2IE	BIT(1)	/* Alarm 2 interrupt enable bit */
#define ISL12057_REG_INT_INTCN	BIT(2)	/* Interrupt control enable bit */
#define ISL12057_REG_INT_RS1	BIT(3)	/* Freq out control bit 1 */
#define ISL12057_REG_INT_RS2	BIT(4)	/* Freq out control bit 2 */
#define ISL12057_REG_INT_EOSC	BIT(7)	/* Oscillator enable bit */

#define ISL12057_REG_SR		0x0F
#define ISL12057_REG_SR_A1F	BIT(0)	/* Alarm 1 interrupt bit */
#define ISL12057_REG_SR_A2F	BIT(1)	/* Alarm 2 interrupt bit */
#define ISL12057_REG_SR_OSF	BIT(7)	/* Oscillator failure bit */

/* Register memory map length */
#define ISL12057_MEM_MAP_LEN	0x10

struct isl12057_rtc_data {
	struct rtc_device *rtc;
	struct regmap *regmap;
	struct mutex lock;
	int irq;
};

static void isl12057_rtc_regs_to_tm(struct rtc_time *tm, u8 *regs)
{
	tm->tm_sec = bcd2bin(regs[ISL12057_REG_RTC_SC]);
	tm->tm_min = bcd2bin(regs[ISL12057_REG_RTC_MN]);

	if (regs[ISL12057_REG_RTC_HR] & ISL12057_REG_RTC_HR_MIL) { /* AM/PM */
		tm->tm_hour = bcd2bin(regs[ISL12057_REG_RTC_HR] & 0x1f);
		if (regs[ISL12057_REG_RTC_HR] & ISL12057_REG_RTC_HR_PM)
			tm->tm_hour += 12;
	} else {					    /* 24 hour mode */
		tm->tm_hour = bcd2bin(regs[ISL12057_REG_RTC_HR] & 0x3f);
	}

	tm->tm_mday = bcd2bin(regs[ISL12057_REG_RTC_DT]);
	tm->tm_wday = bcd2bin(regs[ISL12057_REG_RTC_DW]) - 1; /* starts at 1 */
	tm->tm_mon  = bcd2bin(regs[ISL12057_REG_RTC_MO] & 0x1f) - 1; /* ditto */
	tm->tm_year = bcd2bin(regs[ISL12057_REG_RTC_YR]) + 100;

	/* Check if years register has overflown from 99 to 00 */
	if (regs[ISL12057_REG_RTC_MO] & ISL12057_REG_RTC_MO_CEN)
		tm->tm_year += 100;
}

static int isl12057_rtc_tm_to_regs(u8 *regs, struct rtc_time *tm)
{
	u8 century_bit;

	/*
	 * The clock has an 8 bit wide bcd-coded register for the year.
	 * It also has a century bit encoded in MO flag which provides
	 * information about overflow of year register from 99 to 00.
	 * tm_year is an offset from 1900 and we are interested in the
	 * 2000-2199 range, so any value less than 100 or larger than
	 * 299 is invalid.
	 */
	if (tm->tm_year < 100 || tm->tm_year > 299)
		return -EINVAL;

	century_bit = (tm->tm_year > 199) ? ISL12057_REG_RTC_MO_CEN : 0;

	regs[ISL12057_REG_RTC_SC] = bin2bcd(tm->tm_sec);
	regs[ISL12057_REG_RTC_MN] = bin2bcd(tm->tm_min);
	regs[ISL12057_REG_RTC_HR] = bin2bcd(tm->tm_hour); /* 24-hour format */
	regs[ISL12057_REG_RTC_DT] = bin2bcd(tm->tm_mday);
	regs[ISL12057_REG_RTC_MO] = bin2bcd(tm->tm_mon + 1) | century_bit;
	regs[ISL12057_REG_RTC_YR] = bin2bcd(tm->tm_year % 100);
	regs[ISL12057_REG_RTC_DW] = bin2bcd(tm->tm_wday + 1);

	return 0;
}

/*
 * Try and match register bits w/ fixed null values to see whether we
 * are dealing with an ISL12057. Note: this function is called early
 * during init and hence does need mutex protection.
 */
static int isl12057_i2c_validate_chip(struct regmap *regmap)
{
	u8 regs[ISL12057_MEM_MAP_LEN];
	static const u8 mask[ISL12057_MEM_MAP_LEN] = { 0x80, 0x80, 0x80, 0xf8,
						       0xc0, 0x60, 0x00, 0x00,
						       0x00, 0x00, 0x00, 0x00,
						       0x00, 0x00, 0x60, 0x7c };
	int ret, i;

	ret = regmap_bulk_read(regmap, 0, regs, ISL12057_MEM_MAP_LEN);
	if (ret)
		return ret;

	for (i = 0; i < ISL12057_MEM_MAP_LEN; ++i) {
		if (regs[i] & mask[i])	/* check if bits are cleared */
			return -ENODEV;
	}

	return 0;
}

static int _isl12057_rtc_clear_alarm(struct device *dev)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	int ret;

	ret = regmap_update_bits(data->regmap, ISL12057_REG_SR,
				 ISL12057_REG_SR_A1F, 0);
	if (ret)
		dev_err(dev, "%s: clearing alarm failed (%d)\n", __func__, ret);

	return ret;
}

static int _isl12057_rtc_update_alarm(struct device *dev, int enable)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	int ret;

	ret = regmap_update_bits(data->regmap, ISL12057_REG_INT,
				 ISL12057_REG_INT_A1IE,
				 enable ? ISL12057_REG_INT_A1IE : 0);
	if (ret)
		dev_err(dev, "%s: changing alarm interrupt flag failed (%d)\n",
			__func__, ret);

	return ret;
}

/*
 * Note: as we only read from device and do not perform any update, there is
 * no need for an equivalent function which would try and get driver's main
 * lock. Here, it is safe for everyone if we just use regmap internal lock
 * on the device when reading.
 */
static int _isl12057_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	u8 regs[ISL12057_RTC_SEC_LEN];
	unsigned int sr;
	int ret;

	ret = regmap_read(data->regmap, ISL12057_REG_SR, &sr);
	if (ret) {
		dev_err(dev, "%s: unable to read oscillator status flag (%d)\n",
			__func__, ret);
		goto out;
	} else {
		if (sr & ISL12057_REG_SR_OSF) {
			ret = -ENODATA;
			goto out;
		}
	}

	ret = regmap_bulk_read(data->regmap, ISL12057_REG_RTC_SC, regs,
			       ISL12057_RTC_SEC_LEN);
	if (ret)
		dev_err(dev, "%s: unable to read RTC time section (%d)\n",
			__func__, ret);

out:
	if (ret)
		return ret;

	isl12057_rtc_regs_to_tm(tm, regs);

	return rtc_valid_tm(tm);
}

static int isl12057_rtc_update_alarm(struct device *dev, int enable)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	int ret;

	mutex_lock(&data->lock);
	ret = _isl12057_rtc_update_alarm(dev, enable);
	mutex_unlock(&data->lock);

	return ret;
}

static int isl12057_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	struct rtc_time *alarm_tm = &alarm->time;
	u8 regs[ISL12057_A1_SEC_LEN];
	unsigned int ir;
	int ret;

	mutex_lock(&data->lock);
	ret = regmap_bulk_read(data->regmap, ISL12057_REG_A1_SC, regs,
			       ISL12057_A1_SEC_LEN);
	if (ret) {
		dev_err(dev, "%s: reading alarm section failed (%d)\n",
			__func__, ret);
		goto err_unlock;
	}

	alarm_tm->tm_sec  = bcd2bin(regs[0] & 0x7f);
	alarm_tm->tm_min  = bcd2bin(regs[1] & 0x7f);
	alarm_tm->tm_hour = bcd2bin(regs[2] & 0x3f);
	alarm_tm->tm_mday = bcd2bin(regs[3] & 0x3f);

	ret = regmap_read(data->regmap, ISL12057_REG_INT, &ir);
	if (ret) {
		dev_err(dev, "%s: reading alarm interrupt flag failed (%d)\n",
			__func__, ret);
		goto err_unlock;
	}

	alarm->enabled = !!(ir & ISL12057_REG_INT_A1IE);

err_unlock:
	mutex_unlock(&data->lock);

	return ret;
}

static int isl12057_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	struct rtc_time *alarm_tm = &alarm->time;
	unsigned long rtc_secs, alarm_secs;
	u8 regs[ISL12057_A1_SEC_LEN];
	struct rtc_time rtc_tm;
	int ret, enable = 1;

	mutex_lock(&data->lock);
	ret = _isl12057_rtc_read_time(dev, &rtc_tm);
	if (ret)
		goto err_unlock;

	ret = rtc_tm_to_time(&rtc_tm, &rtc_secs);
	if (ret)
		goto err_unlock;

	ret = rtc_tm_to_time(alarm_tm, &alarm_secs);
	if (ret)
		goto err_unlock;

	/* If alarm time is before current time, disable the alarm */
	if (!alarm->enabled || alarm_secs <= rtc_secs) {
		enable = 0;
	} else {
		/*
		 * Chip only support alarms up to one month in the future. Let's
		 * return an error if we get something after that limit.
		 * Comparison is done by incrementing rtc_tm month field by one
		 * and checking alarm value is still below.
		 */
		if (rtc_tm.tm_mon == 11) { /* handle year wrapping */
			rtc_tm.tm_mon = 0;
			rtc_tm.tm_year += 1;
		} else {
			rtc_tm.tm_mon += 1;
		}

		ret = rtc_tm_to_time(&rtc_tm, &rtc_secs);
		if (ret)
			goto err_unlock;

		if (alarm_secs > rtc_secs) {
			dev_err(dev, "%s: max for alarm is one month (%d)\n",
				__func__, ret);
			ret = -EINVAL;
			goto err_unlock;
		}
	}

	/* Disable the alarm before modifying it */
	ret = _isl12057_rtc_update_alarm(dev, 0);
	if (ret < 0) {
		dev_err(dev, "%s: unable to disable the alarm (%d)\n",
			__func__, ret);
		goto err_unlock;
	}

	/* Program alarm registers */
	regs[0] = bin2bcd(alarm_tm->tm_sec) & 0x7f;
	regs[1] = bin2bcd(alarm_tm->tm_min) & 0x7f;
	regs[2] = bin2bcd(alarm_tm->tm_hour) & 0x3f;
	regs[3] = bin2bcd(alarm_tm->tm_mday) & 0x3f;

	ret = regmap_bulk_write(data->regmap, ISL12057_REG_A1_SC, regs,
				ISL12057_A1_SEC_LEN);
	if (ret < 0) {
		dev_err(dev, "%s: writing alarm section failed (%d)\n",
			__func__, ret);
		goto err_unlock;
	}

	/* Enable or disable alarm */
	ret = _isl12057_rtc_update_alarm(dev, enable);

err_unlock:
	mutex_unlock(&data->lock);

	return ret;
}

static int isl12057_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	u8 regs[ISL12057_RTC_SEC_LEN];
	int ret;

	ret = isl12057_rtc_tm_to_regs(regs, tm);
	if (ret)
		return ret;

	mutex_lock(&data->lock);
	ret = regmap_bulk_write(data->regmap, ISL12057_REG_RTC_SC, regs,
				ISL12057_RTC_SEC_LEN);
	if (ret) {
		dev_err(dev, "%s: unable to write RTC time section (%d)\n",
			__func__, ret);
		goto out;
	}

	/*
	 * Now that RTC time has been updated, let's clear oscillator
	 * failure flag, if needed.
	 */
	ret = regmap_update_bits(data->regmap, ISL12057_REG_SR,
				 ISL12057_REG_SR_OSF, 0);
	if (ret < 0)
		dev_err(dev, "%s: unable to clear osc. failure bit (%d)\n",
			__func__, ret);

out:
	mutex_unlock(&data->lock);

	return ret;
}

/*
 * Check current RTC status and enable/disable what needs to be. Return 0 if
 * everything went ok and a negative value upon error. Note: this function
 * is called early during init and hence does need mutex protection.
 */
static int isl12057_check_rtc_status(struct device *dev, struct regmap *regmap)
{
	int ret;

	/* Enable oscillator if not already running */
	ret = regmap_update_bits(regmap, ISL12057_REG_INT,
				 ISL12057_REG_INT_EOSC, 0);
	if (ret < 0) {
		dev_err(dev, "%s: unable to enable oscillator (%d)\n",
			__func__, ret);
		return ret;
	}

	/* Clear alarm bit if needed */
	ret = regmap_update_bits(regmap, ISL12057_REG_SR,
				 ISL12057_REG_SR_A1F, 0);
	if (ret < 0) {
		dev_err(dev, "%s: unable to clear alarm bit (%d)\n",
			__func__, ret);
		return ret;
	}

	return 0;
}

#ifdef CONFIG_OF
/*
 * One would expect the device to be marked as a wakeup source only
 * when an IRQ pin of the RTC is routed to an interrupt line of the
 * CPU. In practice, such an IRQ pin can be connected to a PMIC and
 * this allows the device to be powered up when RTC alarm rings. This
 * is for instance the case on ReadyNAS 102, 104 and 2120. On those
 * devices with no IRQ driectly connected to the SoC, the RTC chip
 * can be forced as a wakeup source by stating that explicitly in
 * the device's .dts file using the "wakeup-source" boolean property.
 * This will guarantee 'wakealarm' sysfs entry is available on the device.
 *
 * The function below returns 1, i.e. the capability of the chip to
 * wakeup the device, based on IRQ availability or if the boolean
 * property has been set in the .dts file. Otherwise, it returns 0.
 */

static bool isl12057_can_wakeup_machine(struct device *dev)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);

	return data->irq || of_property_read_bool(dev->of_node, "wakeup-source")
		|| of_property_read_bool(dev->of_node, /* legacy */
					 "isil,irq2-can-wakeup-machine");
}
#else
static bool isl12057_can_wakeup_machine(struct device *dev)
{
	struct isl12057_rtc_data *data = dev_get_drvdata(dev);

	return !!data->irq;
}
#endif

static int isl12057_rtc_alarm_irq_enable(struct device *dev,
					 unsigned int enable)
{
	struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);
	int ret = -ENOTTY;

	if (rtc_data->irq)
		ret = isl12057_rtc_update_alarm(dev, enable);

	return ret;
}

static irqreturn_t isl12057_rtc_interrupt(int irq, void *data)
{
	struct i2c_client *client = data;
	struct isl12057_rtc_data *rtc_data = dev_get_drvdata(&client->dev);
	struct rtc_device *rtc = rtc_data->rtc;
	int ret, handled = IRQ_NONE;
	unsigned int sr;

	ret = regmap_read(rtc_data->regmap, ISL12057_REG_SR, &sr);
	if (!ret && (sr & ISL12057_REG_SR_A1F)) {
		dev_dbg(&client->dev, "RTC alarm!\n");

		rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);

		/* Acknowledge and disable the alarm */
		_isl12057_rtc_clear_alarm(&client->dev);
		_isl12057_rtc_update_alarm(&client->dev, 0);

		handled = IRQ_HANDLED;
	}

	return handled;
}

static const struct rtc_class_ops rtc_ops = {
	.read_time = _isl12057_rtc_read_time,
	.set_time = isl12057_rtc_set_time,
	.read_alarm = isl12057_rtc_read_alarm,
	.set_alarm = isl12057_rtc_set_alarm,
	.alarm_irq_enable = isl12057_rtc_alarm_irq_enable,
};

static const struct regmap_config isl12057_rtc_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
};

static int isl12057_probe(struct i2c_client *client,
			  const struct i2c_device_id *id)
{
	struct device *dev = &client->dev;
	struct isl12057_rtc_data *data;
	struct regmap *regmap;
	int ret;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
				     I2C_FUNC_SMBUS_BYTE_DATA |
				     I2C_FUNC_SMBUS_I2C_BLOCK))
		return -ENODEV;

	regmap = devm_regmap_init_i2c(client, &isl12057_rtc_regmap_config);
	if (IS_ERR(regmap)) {
		ret = PTR_ERR(regmap);
		dev_err(dev, "%s: regmap allocation failed (%d)\n",
			__func__, ret);
		return ret;
	}

	ret = isl12057_i2c_validate_chip(regmap);
	if (ret)
		return ret;

	ret = isl12057_check_rtc_status(dev, regmap);
	if (ret)
		return ret;

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	mutex_init(&data->lock);
	data->regmap = regmap;
	dev_set_drvdata(dev, data);

	if (client->irq > 0) {
		ret = devm_request_threaded_irq(dev, client->irq, NULL,
						isl12057_rtc_interrupt,
						IRQF_SHARED|IRQF_ONESHOT,
						DRV_NAME, client);
		if (!ret)
			data->irq = client->irq;
		else
			dev_err(dev, "%s: irq %d unavailable (%d)\n", __func__,
				client->irq, ret);
	}

	if (isl12057_can_wakeup_machine(dev))
		device_init_wakeup(dev, true);

	data->rtc = devm_rtc_device_register(dev, DRV_NAME, &rtc_ops,
					     THIS_MODULE);
	ret = PTR_ERR_OR_ZERO(data->rtc);
	if (ret) {
		dev_err(dev, "%s: unable to register RTC device (%d)\n",
			__func__, ret);
		goto err;
	}

	/* We cannot support UIE mode if we do not have an IRQ line */
	if (!data->irq)
		data->rtc->uie_unsupported = 1;

err:
	return ret;
}

static int isl12057_remove(struct i2c_client *client)
{
	if (isl12057_can_wakeup_machine(&client->dev))
		device_init_wakeup(&client->dev, false);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int isl12057_rtc_suspend(struct device *dev)
{
	struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);

	if (rtc_data->irq && device_may_wakeup(dev))
		return enable_irq_wake(rtc_data->irq);

	return 0;
}

static int isl12057_rtc_resume(struct device *dev)
{
	struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);

	if (rtc_data->irq && device_may_wakeup(dev))
		return disable_irq_wake(rtc_data->irq);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(isl12057_rtc_pm_ops, isl12057_rtc_suspend,
			 isl12057_rtc_resume);

#ifdef CONFIG_OF
static const struct of_device_id isl12057_dt_match[] = {
	{ .compatible = "isl,isl12057" }, /* for backward compat., don't use */
	{ .compatible = "isil,isl12057" },
	{ },
};
MODULE_DEVICE_TABLE(of, isl12057_dt_match);
#endif

static const struct i2c_device_id isl12057_id[] = {
	{ "isl12057", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, isl12057_id);

static struct i2c_driver isl12057_driver = {
	.driver = {
		.name = DRV_NAME,
		.pm = &isl12057_rtc_pm_ops,
		.of_match_table = of_match_ptr(isl12057_dt_match),
	},
	.probe	  = isl12057_probe,
	.remove	  = isl12057_remove,
	.id_table = isl12057_id,
};
module_i2c_driver(isl12057_driver);

MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>");
MODULE_DESCRIPTION("Intersil ISL12057 RTC driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
70e12337 AE	1	/*
	2	* rtc-isl12057 - Driver for Intersil ISL12057 I2C Real Time Clock
	3	*
	4	* Copyright (C) 2013, Arnaud EBALARD <arno@natisbad.org>
	5	*
	6	* This work is largely based on Intersil ISL1208 driver developed by
	7	* Hebert Valerio Riedel <hvr@gnu.org>.
	8	*
	9	* Detailed datasheet on which this development is based is available here:
	10	*
	11	* http://natisbad.org/NAS2/refs/ISL12057.pdf
	12	*
	13	* This program is free software; you can redistribute it and/or modify
	14	* it under the terms of the GNU General Public License as published by
	15	* the Free Software Foundation; either version 2 of the License, or
	16	* (at your option) any later version.
	17	*
	18	* This program is distributed in the hope that it will be useful,
	19	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	20	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	21	* GNU General Public License for more details.
	22	*/
	23
	24	#include <linux/module.h>
	25	#include <linux/mutex.h>
	26	#include <linux/rtc.h>
	27	#include <linux/i2c.h>
	28	#include <linux/bcd.h>
70e12337 AE	29	#include <linux/of.h>
	30	#include <linux/of_device.h>
	31	#include <linux/regmap.h>
	32
	33	#define DRV_NAME "rtc-isl12057"
	34
	35	/* RTC section */
	36	#define ISL12057_REG_RTC_SC 0x00 /* Seconds */
	37	#define ISL12057_REG_RTC_MN 0x01 /* Minutes */
	38	#define ISL12057_REG_RTC_HR 0x02 /* Hours */
	39	#define ISL12057_REG_RTC_HR_PM BIT(5) /* AM/PM bit in 12h format */
	40	#define ISL12057_REG_RTC_HR_MIL BIT(6) /* 24h/12h format */
	41	#define ISL12057_REG_RTC_DW 0x03 /* Day of the Week */
	42	#define ISL12057_REG_RTC_DT 0x04 /* Date */
	43	#define ISL12057_REG_RTC_MO 0x05 /* Month */
b5f4184d	44	#define ISL12057_REG_RTC_MO_CEN BIT(7) /* Century bit */
70e12337 AE	45	#define ISL12057_REG_RTC_YR 0x06 /* Year */
	46	#define ISL12057_RTC_SEC_LEN 7
	47
	48	/* Alarm 1 section */
	49	#define ISL12057_REG_A1_SC 0x07 /* Alarm 1 Seconds */
	50	#define ISL12057_REG_A1_MN 0x08 /* Alarm 1 Minutes */
	51	#define ISL12057_REG_A1_HR 0x09 /* Alarm 1 Hours */
	52	#define ISL12057_REG_A1_HR_PM BIT(5) /* AM/PM bit in 12h format */
	53	#define ISL12057_REG_A1_HR_MIL BIT(6) /* 24h/12h format */
	54	#define ISL12057_REG_A1_DWDT 0x0A /* Alarm 1 Date / Day of the week */
	55	#define ISL12057_REG_A1_DWDT_B BIT(6) /* DW / DT selection bit */
	56	#define ISL12057_A1_SEC_LEN 4
	57
	58	/* Alarm 2 section */
	59	#define ISL12057_REG_A2_MN 0x0B /* Alarm 2 Minutes */
	60	#define ISL12057_REG_A2_HR 0x0C /* Alarm 2 Hours */
	61	#define ISL12057_REG_A2_DWDT 0x0D /* Alarm 2 Date / Day of the week */
	62	#define ISL12057_A2_SEC_LEN 3
	63
	64	/* Control/Status registers */
	65	#define ISL12057_REG_INT 0x0E
	66	#define ISL12057_REG_INT_A1IE BIT(0) /* Alarm 1 interrupt enable bit */
	67	#define ISL12057_REG_INT_A2IE BIT(1) /* Alarm 2 interrupt enable bit */
	68	#define ISL12057_REG_INT_INTCN BIT(2) /* Interrupt control enable bit */
	69	#define ISL12057_REG_INT_RS1 BIT(3) /* Freq out control bit 1 */
	70	#define ISL12057_REG_INT_RS2 BIT(4) /* Freq out control bit 2 */
	71	#define ISL12057_REG_INT_EOSC BIT(7) /* Oscillator enable bit */
	72
	73	#define ISL12057_REG_SR 0x0F
	74	#define ISL12057_REG_SR_A1F BIT(0) /* Alarm 1 interrupt bit */
	75	#define ISL12057_REG_SR_A2F BIT(1) /* Alarm 2 interrupt bit */
	76	#define ISL12057_REG_SR_OSF BIT(7) /* Oscillator failure bit */
	77
	78	/* Register memory map length */
	79	#define ISL12057_MEM_MAP_LEN 0x10
	80
	81	struct isl12057_rtc_data {
fd71493d	82	struct rtc_device *rtc;
70e12337 AE	83	struct regmap *regmap;
70e12337 AE	84	struct mutex lock;
fd71493d	85	int irq;
70e12337 AE	86	};
	87
	88	static void isl12057_rtc_regs_to_tm(struct rtc_time tm, u8 regs)
	89	{
	90	tm->tm_sec = bcd2bin(regs[ISL12057_REG_RTC_SC]);
	91	tm->tm_min = bcd2bin(regs[ISL12057_REG_RTC_MN]);
	92
	93	if (regs[ISL12057_REG_RTC_HR] & ISL12057_REG_RTC_HR_MIL) { /* AM/PM */
5945b288	94	tm->tm_hour = bcd2bin(regs[ISL12057_REG_RTC_HR] & 0x1f);
70e12337 AE	95	if (regs[ISL12057_REG_RTC_HR] & ISL12057_REG_RTC_HR_PM)
	96	tm->tm_hour += 12;
	97	} else { /* 24 hour mode */
	98	tm->tm_hour = bcd2bin(regs[ISL12057_REG_RTC_HR] & 0x3f);
	99	}
	100
	101	tm->tm_mday = bcd2bin(regs[ISL12057_REG_RTC_DT]);
	102	tm->tm_wday = bcd2bin(regs[ISL12057_REG_RTC_DW]) - 1; /* starts at 1 */
5945b288	103	tm->tm_mon = bcd2bin(regs[ISL12057_REG_RTC_MO] & 0x1f) - 1; /* ditto */
70e12337	104	tm->tm_year = bcd2bin(regs[ISL12057_REG_RTC_YR]) + 100;
b5f4184d AE	105
	106	/* Check if years register has overflown from 99 to 00 */
	107	if (regs[ISL12057_REG_RTC_MO] & ISL12057_REG_RTC_MO_CEN)
	108	tm->tm_year += 100;
70e12337 AE	109	}
	110
	111	static int isl12057_rtc_tm_to_regs(u8 regs, struct rtc_time tm)
	112	{
b5f4184d AE	113	u8 century_bit;
b5f4184d AE	114
70e12337 AE	115	/*
70e12337 AE	116	* The clock has an 8 bit wide bcd-coded register for the year.
b5f4184d AE	117	* It also has a century bit encoded in MO flag which provides
b5f4184d AE	118	* information about overflow of year register from 99 to 00.
70e12337	119	* tm_year is an offset from 1900 and we are interested in the
b5f4184d AE	120	* 2000-2199 range, so any value less than 100 or larger than
b5f4184d AE	121	* 299 is invalid.
70e12337	122	*/
b5f4184d	123	if (tm->tm_year < 100 \|\| tm->tm_year > 299)
70e12337 AE	124	return -EINVAL;
70e12337 AE	125
b5f4184d AE	126	century_bit = (tm->tm_year > 199) ? ISL12057_REG_RTC_MO_CEN : 0;
b5f4184d AE	127
70e12337 AE	128	regs[ISL12057_REG_RTC_SC] = bin2bcd(tm->tm_sec);
	129	regs[ISL12057_REG_RTC_MN] = bin2bcd(tm->tm_min);
	130	regs[ISL12057_REG_RTC_HR] = bin2bcd(tm->tm_hour); /* 24-hour format */
	131	regs[ISL12057_REG_RTC_DT] = bin2bcd(tm->tm_mday);
b5f4184d AE	132	regs[ISL12057_REG_RTC_MO] = bin2bcd(tm->tm_mon + 1) \| century_bit;
b5f4184d AE	133	regs[ISL12057_REG_RTC_YR] = bin2bcd(tm->tm_year % 100);
70e12337 AE	134	regs[ISL12057_REG_RTC_DW] = bin2bcd(tm->tm_wday + 1);
	135
	136	return 0;
	137	}
	138
	139	/*
	140	* Try and match register bits w/ fixed null values to see whether we
	141	* are dealing with an ISL12057. Note: this function is called early
	142	* during init and hence does need mutex protection.
	143	*/
	144	static int isl12057_i2c_validate_chip(struct regmap *regmap)
	145	{
	146	u8 regs[ISL12057_MEM_MAP_LEN];
	147	static const u8 mask[ISL12057_MEM_MAP_LEN] = { 0x80, 0x80, 0x80, 0xf8,
	148	0xc0, 0x60, 0x00, 0x00,
	149	0x00, 0x00, 0x00, 0x00,
	150	0x00, 0x00, 0x60, 0x7c };
	151	int ret, i;
	152
	153	ret = regmap_bulk_read(regmap, 0, regs, ISL12057_MEM_MAP_LEN);
	154	if (ret)
	155	return ret;
	156
	157	for (i = 0; i < ISL12057_MEM_MAP_LEN; ++i) {
	158	if (regs[i] & mask[i]) /* check if bits are cleared */
	159	return -ENODEV;
	160	}
	161
	162	return 0;
	163	}
	164
fd71493d AE	165	static int _isl12057_rtc_clear_alarm(struct device *dev)
	166	{
	167	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	168	int ret;
	169
	170	ret = regmap_update_bits(data->regmap, ISL12057_REG_SR,
	171	ISL12057_REG_SR_A1F, 0);
	172	if (ret)
	173	dev_err(dev, "%s: clearing alarm failed (%d)\n", __func__, ret);
	174
	175	return ret;
	176	}
	177
	178	static int _isl12057_rtc_update_alarm(struct device *dev, int enable)
	179	{
	180	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	181	int ret;
	182
	183	ret = regmap_update_bits(data->regmap, ISL12057_REG_INT,
	184	ISL12057_REG_INT_A1IE,
	185	enable ? ISL12057_REG_INT_A1IE : 0);
	186	if (ret)
	187	dev_err(dev, "%s: changing alarm interrupt flag failed (%d)\n",
	188	__func__, ret);
	189
	190	return ret;
	191	}
	192
	193	/*
	194	* Note: as we only read from device and do not perform any update, there is
	195	* no need for an equivalent function which would try and get driver's main
	196	* lock. Here, it is safe for everyone if we just use regmap internal lock
	197	* on the device when reading.
	198	*/
	199	static int _isl12057_rtc_read_time(struct device dev, struct rtc_time tm)
70e12337 AE	200	{
	201	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	202	u8 regs[ISL12057_RTC_SEC_LEN];
10df1e67	203	unsigned int sr;
70e12337 AE	204	int ret;
70e12337 AE	205
10df1e67 AE	206	ret = regmap_read(data->regmap, ISL12057_REG_SR, &sr);
10df1e67 AE	207	if (ret) {
cf67d0b6 AE	208	dev_err(dev, "%s: unable to read oscillator status flag (%d)\n",
cf67d0b6 AE	209	__func__, ret);
10df1e67 AE	210	goto out;
	211	} else {
	212	if (sr & ISL12057_REG_SR_OSF) {
	213	ret = -ENODATA;
	214	goto out;
	215	}
	216	}
	217
70e12337 AE	218	ret = regmap_bulk_read(data->regmap, ISL12057_REG_RTC_SC, regs,
70e12337 AE	219	ISL12057_RTC_SEC_LEN);
10df1e67	220	if (ret)
cf67d0b6 AE	221	dev_err(dev, "%s: unable to read RTC time section (%d)\n",
cf67d0b6 AE	222	__func__, ret);
10df1e67 AE	223
10df1e67 AE	224	out:
10df1e67	225	if (ret)
70e12337	226	return ret;
70e12337 AE	227
	228	isl12057_rtc_regs_to_tm(tm, regs);
	229
	230	return rtc_valid_tm(tm);
	231	}
	232
fd71493d AE	233	static int isl12057_rtc_update_alarm(struct device *dev, int enable)
	234	{
	235	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	236	int ret;
	237
	238	mutex_lock(&data->lock);
	239	ret = _isl12057_rtc_update_alarm(dev, enable);
	240	mutex_unlock(&data->lock);
	241
	242	return ret;
	243	}
	244
	245	static int isl12057_rtc_read_alarm(struct device dev, struct rtc_wkalrm alarm)
	246	{
	247	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
bea9db3d	248	struct rtc_time *alarm_tm = &alarm->time;
fd71493d AE	249	u8 regs[ISL12057_A1_SEC_LEN];
	250	unsigned int ir;
	251	int ret;
	252
	253	mutex_lock(&data->lock);
	254	ret = regmap_bulk_read(data->regmap, ISL12057_REG_A1_SC, regs,
	255	ISL12057_A1_SEC_LEN);
	256	if (ret) {
	257	dev_err(dev, "%s: reading alarm section failed (%d)\n",
	258	__func__, ret);
	259	goto err_unlock;
	260	}
	261
	262	alarm_tm->tm_sec = bcd2bin(regs[0] & 0x7f);
	263	alarm_tm->tm_min = bcd2bin(regs[1] & 0x7f);
	264	alarm_tm->tm_hour = bcd2bin(regs[2] & 0x3f);
	265	alarm_tm->tm_mday = bcd2bin(regs[3] & 0x3f);
fd71493d AE	266
	267	ret = regmap_read(data->regmap, ISL12057_REG_INT, &ir);
	268	if (ret) {
	269	dev_err(dev, "%s: reading alarm interrupt flag failed (%d)\n",
	270	__func__, ret);
	271	goto err_unlock;
	272	}
	273
	274	alarm->enabled = !!(ir & ISL12057_REG_INT_A1IE);
	275
	276	err_unlock:
	277	mutex_unlock(&data->lock);
	278
	279	return ret;
	280	}
	281
	282	static int isl12057_rtc_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	283	{
	284	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	285	struct rtc_time *alarm_tm = &alarm->time;
	286	unsigned long rtc_secs, alarm_secs;
	287	u8 regs[ISL12057_A1_SEC_LEN];
	288	struct rtc_time rtc_tm;
	289	int ret, enable = 1;
	290
	291	mutex_lock(&data->lock);
	292	ret = _isl12057_rtc_read_time(dev, &rtc_tm);
	293	if (ret)
	294	goto err_unlock;
	295
	296	ret = rtc_tm_to_time(&rtc_tm, &rtc_secs);
	297	if (ret)
	298	goto err_unlock;
	299
	300	ret = rtc_tm_to_time(alarm_tm, &alarm_secs);
	301	if (ret)
	302	goto err_unlock;
	303
	304	/* If alarm time is before current time, disable the alarm */
	305	if (!alarm->enabled \|\| alarm_secs <= rtc_secs) {
	306	enable = 0;
	307	} else {
	308	/*
	309	* Chip only support alarms up to one month in the future. Let's
	310	* return an error if we get something after that limit.
	311	* Comparison is done by incrementing rtc_tm month field by one
	312	* and checking alarm value is still below.
	313	*/
	314	if (rtc_tm.tm_mon == 11) { /* handle year wrapping */
	315	rtc_tm.tm_mon = 0;
	316	rtc_tm.tm_year += 1;
	317	} else {
	318	rtc_tm.tm_mon += 1;
	319	}
	320
	321	ret = rtc_tm_to_time(&rtc_tm, &rtc_secs);
	322	if (ret)
	323	goto err_unlock;
	324
	325	if (alarm_secs > rtc_secs) {
	326	dev_err(dev, "%s: max for alarm is one month (%d)\n",
	327	__func__, ret);
	328	ret = -EINVAL;
	329	goto err_unlock;
330	}
331	}
332
333	/* Disable the alarm before modifying it */
334	ret = _isl12057_rtc_update_alarm(dev, 0);
335	if (ret < 0) {
336	dev_err(dev, "%s: unable to disable the alarm (%d)\n",
337	__func__, ret);
338	goto err_unlock;
339	}
340
341	/* Program alarm registers */
342	regs[0] = bin2bcd(alarm_tm->tm_sec) & 0x7f;
343	regs[1] = bin2bcd(alarm_tm->tm_min) & 0x7f;
344	regs[2] = bin2bcd(alarm_tm->tm_hour) & 0x3f;
345	regs[3] = bin2bcd(alarm_tm->tm_mday) & 0x3f;
346
347	ret = regmap_bulk_write(data->regmap, ISL12057_REG_A1_SC, regs,
348	ISL12057_A1_SEC_LEN);
349	if (ret < 0) {
350	dev_err(dev, "%s: writing alarm section failed (%d)\n",
351	__func__, ret);
352	goto err_unlock;
353	}
354
355	/* Enable or disable alarm */
356	ret = _isl12057_rtc_update_alarm(dev, enable);
357
358	err_unlock:
359	mutex_unlock(&data->lock);
360
361	return ret;
362	}
363
70e12337 AE	364	static int isl12057_rtc_set_time(struct device dev, struct rtc_time tm)
	365	{
	366	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	367	u8 regs[ISL12057_RTC_SEC_LEN];
	368	int ret;
	369
	370	ret = isl12057_rtc_tm_to_regs(regs, tm);
	371	if (ret)
	372	return ret;
	373
	374	mutex_lock(&data->lock);
	375	ret = regmap_bulk_write(data->regmap, ISL12057_REG_RTC_SC, regs,
	376	ISL12057_RTC_SEC_LEN);
10df1e67	377	if (ret) {
cf67d0b6 AE	378	dev_err(dev, "%s: unable to write RTC time section (%d)\n",
cf67d0b6 AE	379	__func__, ret);
10df1e67 AE	380	goto out;
10df1e67 AE	381	}
70e12337	382
10df1e67 AE	383	/*
	384	* Now that RTC time has been updated, let's clear oscillator
	385	* failure flag, if needed.
	386	*/
	387	ret = regmap_update_bits(data->regmap, ISL12057_REG_SR,
	388	ISL12057_REG_SR_OSF, 0);
	389	if (ret < 0)
cf67d0b6 AE	390	dev_err(dev, "%s: unable to clear osc. failure bit (%d)\n",
cf67d0b6 AE	391	__func__, ret);
10df1e67 AE	392
	393	out:
	394	mutex_unlock(&data->lock);
70e12337 AE	395
	396	return ret;
	397	}
	398
	399	/*
	400	* Check current RTC status and enable/disable what needs to be. Return 0 if
	401	* everything went ok and a negative value upon error. Note: this function
	402	* is called early during init and hence does need mutex protection.
	403	*/
	404	static int isl12057_check_rtc_status(struct device dev, struct regmap regmap)
	405	{
	406	int ret;
	407
	408	/* Enable oscillator if not already running */
	409	ret = regmap_update_bits(regmap, ISL12057_REG_INT,
	410	ISL12057_REG_INT_EOSC, 0);
	411	if (ret < 0) {
cf67d0b6 AE	412	dev_err(dev, "%s: unable to enable oscillator (%d)\n",
cf67d0b6 AE	413	__func__, ret);
70e12337 AE	414	return ret;
	415	}
	416
	417	/* Clear alarm bit if needed */
	418	ret = regmap_update_bits(regmap, ISL12057_REG_SR,
	419	ISL12057_REG_SR_A1F, 0);
	420	if (ret < 0) {
cf67d0b6 AE	421	dev_err(dev, "%s: unable to clear alarm bit (%d)\n",
cf67d0b6 AE	422	__func__, ret);
70e12337 AE	423	return ret;
	424	}
	425
	426	return 0;
	427	}
	428
298ff012 AE	429	#ifdef CONFIG_OF
	430	/*
	431	* One would expect the device to be marked as a wakeup source only
	432	* when an IRQ pin of the RTC is routed to an interrupt line of the
	433	* CPU. In practice, such an IRQ pin can be connected to a PMIC and
	434	* this allows the device to be powered up when RTC alarm rings. This
	435	* is for instance the case on ReadyNAS 102, 104 and 2120. On those
	436	* devices with no IRQ driectly connected to the SoC, the RTC chip
	437	* can be forced as a wakeup source by stating that explicitly in
f4b67222 SH	438	* the device's .dts file using the "wakeup-source" boolean property.
f4b67222 SH	439	* This will guarantee 'wakealarm' sysfs entry is available on the device.
298ff012 AE	440	*
	441	* The function below returns 1, i.e. the capability of the chip to
	442	* wakeup the device, based on IRQ availability or if the boolean
	443	* property has been set in the .dts file. Otherwise, it returns 0.
	444	*/
	445
	446	static bool isl12057_can_wakeup_machine(struct device *dev)
	447	{
	448	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	449
f4b67222 SH	450	return data->irq \|\| of_property_read_bool(dev->of_node, "wakeup-source")
	451	\|\| of_property_read_bool(dev->of_node, /* legacy */
	452	"isil,irq2-can-wakeup-machine");
298ff012 AE	453	}
	454	#else
	455	static bool isl12057_can_wakeup_machine(struct device *dev)
	456	{
	457	struct isl12057_rtc_data *data = dev_get_drvdata(dev);
	458
	459	return !!data->irq;
	460	}
	461	#endif
	462
fd71493d AE	463	static int isl12057_rtc_alarm_irq_enable(struct device *dev,
	464	unsigned int enable)
	465	{
	466	struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);
	467	int ret = -ENOTTY;
	468
	469	if (rtc_data->irq)
	470	ret = isl12057_rtc_update_alarm(dev, enable);
	471
	472	return ret;
	473	}
	474
	475	static irqreturn_t isl12057_rtc_interrupt(int irq, void *data)
	476	{
	477	struct i2c_client *client = data;
	478	struct isl12057_rtc_data *rtc_data = dev_get_drvdata(&client->dev);
	479	struct rtc_device *rtc = rtc_data->rtc;
	480	int ret, handled = IRQ_NONE;
	481	unsigned int sr;
	482
	483	ret = regmap_read(rtc_data->regmap, ISL12057_REG_SR, &sr);
	484	if (!ret && (sr & ISL12057_REG_SR_A1F)) {
	485	dev_dbg(&client->dev, "RTC alarm!\n");
	486
	487	rtc_update_irq(rtc, 1, RTC_IRQF \| RTC_AF);
	488
	489	/* Acknowledge and disable the alarm */
	490	_isl12057_rtc_clear_alarm(&client->dev);
	491	_isl12057_rtc_update_alarm(&client->dev, 0);
	492
	493	handled = IRQ_HANDLED;
	494	}
	495
	496	return handled;
	497	}
	498
70e12337	499	static const struct rtc_class_ops rtc_ops = {
fd71493d	500	.read_time = _isl12057_rtc_read_time,
70e12337	501	.set_time = isl12057_rtc_set_time,
fd71493d AE	502	.read_alarm = isl12057_rtc_read_alarm,
	503	.set_alarm = isl12057_rtc_set_alarm,
	504	.alarm_irq_enable = isl12057_rtc_alarm_irq_enable,
70e12337 AE	505	};
70e12337 AE	506
1ef2816f	507	static const struct regmap_config isl12057_rtc_regmap_config = {
70e12337 AE	508	.reg_bits = 8,
	509	.val_bits = 8,
	510	};
	511
	512	static int isl12057_probe(struct i2c_client *client,
	513	const struct i2c_device_id *id)
	514	{
	515	struct device *dev = &client->dev;
	516	struct isl12057_rtc_data *data;
70e12337 AE	517	struct regmap *regmap;
	518	int ret;
	519
	520	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C \|
	521	I2C_FUNC_SMBUS_BYTE_DATA \|
	522	I2C_FUNC_SMBUS_I2C_BLOCK))
	523	return -ENODEV;
	524
	525	regmap = devm_regmap_init_i2c(client, &isl12057_rtc_regmap_config);
	526	if (IS_ERR(regmap)) {
	527	ret = PTR_ERR(regmap);
cf67d0b6 AE	528	dev_err(dev, "%s: regmap allocation failed (%d)\n",
cf67d0b6 AE	529	__func__, ret);
70e12337 AE	530	return ret;
	531	}
	532
	533	ret = isl12057_i2c_validate_chip(regmap);
	534	if (ret)
	535	return ret;
	536
	537	ret = isl12057_check_rtc_status(dev, regmap);
	538	if (ret)
	539	return ret;
	540
	541	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	542	if (!data)
	543	return -ENOMEM;
	544
	545	mutex_init(&data->lock);
	546	data->regmap = regmap;
	547	dev_set_drvdata(dev, data);
	548
fd71493d AE	549	if (client->irq > 0) {
	550	ret = devm_request_threaded_irq(dev, client->irq, NULL,
	551	isl12057_rtc_interrupt,
	552	IRQF_SHARED\|IRQF_ONESHOT,
	553	DRV_NAME, client);
	554	if (!ret)
	555	data->irq = client->irq;
	556	else
	557	dev_err(dev, "%s: irq %d unavailable (%d)\n", __func__,
	558	client->irq, ret);
	559	}
	560
298ff012 AE	561	if (isl12057_can_wakeup_machine(dev))
298ff012 AE	562	device_init_wakeup(dev, true);
fd71493d AE	563
	564	data->rtc = devm_rtc_device_register(dev, DRV_NAME, &rtc_ops,
	565	THIS_MODULE);
	566	ret = PTR_ERR_OR_ZERO(data->rtc);
	567	if (ret) {
	568	dev_err(dev, "%s: unable to register RTC device (%d)\n",
	569	__func__, ret);
	570	goto err;
	571	}
	572
	573	/* We cannot support UIE mode if we do not have an IRQ line */
	574	if (!data->irq)
	575	data->rtc->uie_unsupported = 1;
	576
	577	err:
	578	return ret;
	579	}
	580
	581	static int isl12057_remove(struct i2c_client *client)
	582	{
298ff012	583	if (isl12057_can_wakeup_machine(&client->dev))
fd71493d AE	584	device_init_wakeup(&client->dev, false);
	585
	586	return 0;
	587	}
	588
	589	#ifdef CONFIG_PM_SLEEP
	590	static int isl12057_rtc_suspend(struct device *dev)
	591	{
	592	struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);
	593
298ff012	594	if (rtc_data->irq && device_may_wakeup(dev))
fd71493d AE	595	return enable_irq_wake(rtc_data->irq);
	596
	597	return 0;
70e12337 AE	598	}
70e12337 AE	599
fd71493d AE	600	static int isl12057_rtc_resume(struct device *dev)
	601	{
	602	struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);
	603
298ff012	604	if (rtc_data->irq && device_may_wakeup(dev))
fd71493d AE	605	return disable_irq_wake(rtc_data->irq);
	606
	607	return 0;
	608	}
	609	#endif
	610
	611	static SIMPLE_DEV_PM_OPS(isl12057_rtc_pm_ops, isl12057_rtc_suspend,
	612	isl12057_rtc_resume);
	613
70e12337	614	#ifdef CONFIG_OF
8c5bfac0	615	static const struct of_device_id isl12057_dt_match[] = {
401b3c6a AE	616	{ .compatible = "isl,isl12057" }, /* for backward compat., don't use */
401b3c6a AE	617	{ .compatible = "isil,isl12057" },
70e12337 AE	618	{ },
70e12337 AE	619	};
1c4fc295	620	MODULE_DEVICE_TABLE(of, isl12057_dt_match);
70e12337 AE	621	#endif
	622
	623	static const struct i2c_device_id isl12057_id[] = {
	624	{ "isl12057", 0 },
	625	{ }
	626	};
	627	MODULE_DEVICE_TABLE(i2c, isl12057_id);
	628
	629	static struct i2c_driver isl12057_driver = {
	630	.driver = {
	631	.name = DRV_NAME,
fd71493d	632	.pm = &isl12057_rtc_pm_ops,
70e12337 AE	633	.of_match_table = of_match_ptr(isl12057_dt_match),
	634	},
	635	.probe = isl12057_probe,
fd71493d	636	.remove = isl12057_remove,
70e12337 AE	637	.id_table = isl12057_id,
	638	};
	639	module_i2c_driver(isl12057_driver);
	640
	641	MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>");
	642	MODULE_DESCRIPTION("Intersil ISL12057 RTC driver");
	643	MODULE_LICENSE("GPL");