drivers/mfd/max77686.c - kernel/bruno - Git at Google

 /*
  * max77686.c - mfd core driver for the Maxim 77686/802
  *
  * Copyright (C) 2012 Samsung Electronics
  * Chiwoong Byun <woong.byun@smasung.com>
  * Jonghwa Lee <jonghwa3.lee@samsung.com>
  *
  * 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.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  *
  * This driver is based on max8997.c
  */

 #include <linux/export.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>
 #include <linux/pm_runtime.h>
 #include <linux/module.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/max77686.h>
 #include <linux/mfd/max77686-private.h>
 #include <linux/err.h>
 #include <linux/of.h>

 #define I2C_ADDR_RTC	(0x0C >> 1)

 static const struct mfd_cell max77686_devs[] = {
 	{ .name = "max77686-pmic", },
 	{ .name = "max77686-rtc", },
 	{ .name = "max77686-clk", },
 };

 static const struct mfd_cell max77802_devs[] = {
 	{ .name = "max77802-pmic", },
 	{ .name = "max77802-clk", },
 	{ .name = "max77802-rtc", },
 };

 static bool max77802_pmic_is_accessible_reg(struct device *dev,
 					    unsigned int reg)
 {
 	return reg < MAX77802_REG_PMIC_END;
 }

 static bool max77802_rtc_is_accessible_reg(struct device *dev,
 					   unsigned int reg)
 {
 	return (reg >= MAX77802_RTC_INT && reg < MAX77802_RTC_END);
 }

 static bool max77802_is_accessible_reg(struct device *dev, unsigned int reg)
 {
 	return (max77802_pmic_is_accessible_reg(dev, reg) ||
 		max77802_rtc_is_accessible_reg(dev, reg));
 }

 static bool max77802_pmic_is_precious_reg(struct device *dev, unsigned int reg)
 {
 	return (reg == MAX77802_REG_INTSRC || reg == MAX77802_REG_INT1 ||
 		reg == MAX77802_REG_INT2);
 }

 static bool max77802_rtc_is_precious_reg(struct device *dev, unsigned int reg)
 {
 	return (reg == MAX77802_RTC_INT ||
 		reg == MAX77802_RTC_UPDATE0 ||
 		reg == MAX77802_RTC_UPDATE1);
 }

 static bool max77802_is_precious_reg(struct device *dev, unsigned int reg)
 {
 	return (max77802_pmic_is_precious_reg(dev, reg) ||
 		max77802_rtc_is_precious_reg(dev, reg));
 }

 static bool max77802_pmic_is_volatile_reg(struct device *dev, unsigned int reg)
 {
 	return (max77802_is_precious_reg(dev, reg) ||
 		reg == MAX77802_REG_STATUS1 || reg == MAX77802_REG_STATUS2 ||
 		reg == MAX77802_REG_PWRON);
 }

 static bool max77802_rtc_is_volatile_reg(struct device *dev, unsigned int reg)
 {
 	return (max77802_rtc_is_precious_reg(dev, reg) ||
 		reg == MAX77802_RTC_SEC ||
 		reg == MAX77802_RTC_MIN ||
 		reg == MAX77802_RTC_HOUR ||
 		reg == MAX77802_RTC_WEEKDAY ||
 		reg == MAX77802_RTC_MONTH ||
 		reg == MAX77802_RTC_YEAR ||
 		reg == MAX77802_RTC_DATE);
 }

 static bool max77802_is_volatile_reg(struct device *dev, unsigned int reg)
 {
 	return (max77802_pmic_is_volatile_reg(dev, reg) ||
 		max77802_rtc_is_volatile_reg(dev, reg));
 }

 static const struct regmap_config max77686_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 };

 static const struct regmap_config max77686_rtc_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 };

 static const struct regmap_config max77802_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.writeable_reg = max77802_is_accessible_reg,
 	.readable_reg = max77802_is_accessible_reg,
 	.precious_reg = max77802_is_precious_reg,
 	.volatile_reg = max77802_is_volatile_reg,
 	.name = "max77802-pmic",
 	.cache_type = REGCACHE_RBTREE,
 };

 static const struct regmap_irq max77686_irqs[] = {
 	/* INT1 interrupts */
 	{ .reg_offset = 0, .mask = MAX77686_INT1_PWRONF_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_INT1_PWRONR_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_INT1_JIGONBF_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_INT1_JIGONBR_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_INT1_ACOKBF_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_INT1_ACOKBR_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_INT1_ONKEY1S_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_INT1_MRSTB_MSK, },
 	/* INT2 interrupts */
 	{ .reg_offset = 1, .mask = MAX77686_INT2_140C_MSK, },
 	{ .reg_offset = 1, .mask = MAX77686_INT2_120C_MSK, },
 };

 static const struct regmap_irq_chip max77686_irq_chip = {
 	.name			= "max77686-pmic",
 	.status_base		= MAX77686_REG_INT1,
 	.mask_base		= MAX77686_REG_INT1MSK,
 	.num_regs		= 2,
 	.irqs			= max77686_irqs,
 	.num_irqs		= ARRAY_SIZE(max77686_irqs),
 };

 static const struct regmap_irq max77686_rtc_irqs[] = {
 	/* RTC interrupts */
 	{ .reg_offset = 0, .mask = MAX77686_RTCINT_RTC60S_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_RTCINT_RTCA1_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_RTCINT_RTCA2_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_RTCINT_SMPL_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_RTCINT_RTC1S_MSK, },
 	{ .reg_offset = 0, .mask = MAX77686_RTCINT_WTSR_MSK, },
 };

 static const struct regmap_irq_chip max77686_rtc_irq_chip = {
 	.name			= "max77686-rtc",
 	.status_base		= MAX77686_RTC_INT,
 	.mask_base		= MAX77686_RTC_INTM,
 	.num_regs		= 1,
 	.irqs			= max77686_rtc_irqs,
 	.num_irqs		= ARRAY_SIZE(max77686_rtc_irqs),
 };

 static const struct regmap_irq_chip max77802_irq_chip = {
 	.name			= "max77802-pmic",
 	.status_base		= MAX77802_REG_INT1,
 	.mask_base		= MAX77802_REG_INT1MSK,
 	.num_regs		= 2,
 	.irqs			= max77686_irqs, /* same masks as 77686 */
 	.num_irqs		= ARRAY_SIZE(max77686_irqs),
 };

 static const struct regmap_irq_chip max77802_rtc_irq_chip = {
 	.name			= "max77802-rtc",
 	.status_base		= MAX77802_RTC_INT,
 	.mask_base		= MAX77802_RTC_INTM,
 	.num_regs		= 1,
 	.irqs			= max77686_rtc_irqs, /* same masks as 77686 */
 	.num_irqs		= ARRAY_SIZE(max77686_rtc_irqs),
 };

 static const struct of_device_id max77686_pmic_dt_match[] = {
 	{
 		.compatible = "maxim,max77686",
 		.data = (void *)TYPE_MAX77686,
 	},
 	{
 		.compatible = "maxim,max77802",
 		.data = (void *)TYPE_MAX77802,
 	},
 	{ },
 };

 static int max77686_i2c_probe(struct i2c_client *i2c,
 			      const struct i2c_device_id *id)
 {
 	struct max77686_dev *max77686 = NULL;
 	const struct of_device_id *match;
 	unsigned int data;
 	int ret = 0;
 	const struct regmap_config *config;
 	const struct regmap_irq_chip *irq_chip;
 	const struct regmap_irq_chip *rtc_irq_chip;
 	struct regmap **rtc_regmap;
 	const struct mfd_cell *cells;
 	int n_devs;

 	max77686 = devm_kzalloc(&i2c->dev,
 				sizeof(struct max77686_dev), GFP_KERNEL);
 	if (!max77686)
 		return -ENOMEM;

 	if (i2c->dev.of_node) {
 		match = of_match_node(max77686_pmic_dt_match, i2c->dev.of_node);
 		if (!match)
 			return -EINVAL;

 		max77686->type = (unsigned long)match->data;
 	} else
 		max77686->type = id->driver_data;

 	i2c_set_clientdata(i2c, max77686);
 	max77686->dev = &i2c->dev;
 	max77686->i2c = i2c;

 	max77686->irq = i2c->irq;

 	if (max77686->type == TYPE_MAX77686) {
 		config = &max77686_regmap_config;
 		irq_chip = &max77686_irq_chip;
 		rtc_irq_chip = &max77686_rtc_irq_chip;
 		rtc_regmap = &max77686->rtc_regmap;
 		cells =  max77686_devs;
 		n_devs = ARRAY_SIZE(max77686_devs);
 	} else {
 		config = &max77802_regmap_config;
 		irq_chip = &max77802_irq_chip;
 		rtc_irq_chip = &max77802_rtc_irq_chip;
 		rtc_regmap = &max77686->regmap;
 		cells =  max77802_devs;
 		n_devs = ARRAY_SIZE(max77802_devs);
 	}

 	max77686->regmap = devm_regmap_init_i2c(i2c, config);
 	if (IS_ERR(max77686->regmap)) {
 		ret = PTR_ERR(max77686->regmap);
 		dev_err(max77686->dev, "Failed to allocate register map: %d\n",
 				ret);
 		return ret;
 	}

 	ret = regmap_read(max77686->regmap, MAX77686_REG_DEVICE_ID, &data);
 	if (ret < 0) {
 		dev_err(max77686->dev,
 			"device not found on this channel (this is not an error)\n");
 		return -ENODEV;
 	}

 	if (max77686->type == TYPE_MAX77686) {
 		max77686->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC);
 		if (!max77686->rtc) {
 			dev_err(max77686->dev,
 				"Failed to allocate I2C device for RTC\n");
 			return -ENODEV;
 		}
 		i2c_set_clientdata(max77686->rtc, max77686);

 		max77686->rtc_regmap =
 			devm_regmap_init_i2c(max77686->rtc,
 					     &max77686_rtc_regmap_config);
 		if (IS_ERR(max77686->rtc_regmap)) {
 			ret = PTR_ERR(max77686->rtc_regmap);
 			dev_err(max77686->dev,
 				"failed to allocate RTC regmap: %d\n",
 				ret);
 			goto err_unregister_i2c;
 		}
 	}

 	ret = regmap_add_irq_chip(max77686->regmap, max77686->irq,
 				  IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
 				  IRQF_SHARED, 0, irq_chip,
 				  &max77686->irq_data);
 	if (ret) {
 		dev_err(&i2c->dev, "failed to add PMIC irq chip: %d\n", ret);
 		goto err_unregister_i2c;
 	}

 	ret = regmap_add_irq_chip(*rtc_regmap, max77686->irq,
 				  IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
 				  IRQF_SHARED, 0, rtc_irq_chip,
 				  &max77686->rtc_irq_data);
 	if (ret) {
 		dev_err(&i2c->dev, "failed to add RTC irq chip: %d\n", ret);
 		goto err_del_irqc;
 	}

 	ret = mfd_add_devices(max77686->dev, -1, cells, n_devs, NULL, 0, NULL);
 	if (ret < 0) {
 		dev_err(&i2c->dev, "failed to add MFD devices: %d\n", ret);
 		goto err_del_rtc_irqc;
 	}

 	return 0;

 err_del_rtc_irqc:
 	regmap_del_irq_chip(max77686->irq, max77686->rtc_irq_data);
 err_del_irqc:
 	regmap_del_irq_chip(max77686->irq, max77686->irq_data);
 err_unregister_i2c:
 	if (max77686->type == TYPE_MAX77686)
 		i2c_unregister_device(max77686->rtc);

 	return ret;
 }

 static int max77686_i2c_remove(struct i2c_client *i2c)
 {
 	struct max77686_dev *max77686 = i2c_get_clientdata(i2c);

 	mfd_remove_devices(max77686->dev);

 	regmap_del_irq_chip(max77686->irq, max77686->rtc_irq_data);
 	regmap_del_irq_chip(max77686->irq, max77686->irq_data);

 	if (max77686->type == TYPE_MAX77686)
 		i2c_unregister_device(max77686->rtc);

 	return 0;
 }

 static const struct i2c_device_id max77686_i2c_id[] = {
 	{ "max77686", TYPE_MAX77686 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, max77686_i2c_id);

 #ifdef CONFIG_PM_SLEEP
 static int max77686_suspend(struct device *dev)
 {
 	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
 	struct max77686_dev *max77686 = i2c_get_clientdata(i2c);

 	if (device_may_wakeup(dev))
 		enable_irq_wake(max77686->irq);

 	/*
 	 * IRQ must be disabled during suspend because if it happens
 	 * while suspended it will be handled before resuming I2C.
 	 *
 	 * When device is woken up from suspend (e.g. by RTC wake alarm),
 	 * an interrupt occurs before resuming I2C bus controller.
 	 * Interrupt handler tries to read registers but this read
 	 * will fail because I2C is still suspended.
 	 */
 	disable_irq(max77686->irq);

 	return 0;
 }

 static int max77686_resume(struct device *dev)
 {
 	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
 	struct max77686_dev *max77686 = i2c_get_clientdata(i2c);

 	if (device_may_wakeup(dev))
 		disable_irq_wake(max77686->irq);

 	enable_irq(max77686->irq);

 	return 0;
 }
 #endif /* CONFIG_PM_SLEEP */

 static SIMPLE_DEV_PM_OPS(max77686_pm, max77686_suspend, max77686_resume);

 static struct i2c_driver max77686_i2c_driver = {
 	.driver = {
 		   .name = "max77686",
 		   .pm = &max77686_pm,
 		   .of_match_table = of_match_ptr(max77686_pmic_dt_match),
 	},
 	.probe = max77686_i2c_probe,
 	.remove = max77686_i2c_remove,
 	.id_table = max77686_i2c_id,
 };

 static int __init max77686_i2c_init(void)
 {
 	return i2c_add_driver(&max77686_i2c_driver);
 }
 /* init early so consumer devices can complete system boot */
 subsys_initcall(max77686_i2c_init);

 static void __exit max77686_i2c_exit(void)
 {
 	i2c_del_driver(&max77686_i2c_driver);
 }
 module_exit(max77686_i2c_exit);

 MODULE_DESCRIPTION("MAXIM 77686/802 multi-function core driver");
 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
 MODULE_LICENSE("GPL");
	/*
	* max77686.c - mfd core driver for the Maxim 77686/802
	*
	* Copyright (C) 2012 Samsung Electronics
	* Chiwoong Byun <woong.byun@smasung.com>
	* Jonghwa Lee <jonghwa3.lee@samsung.com>
	*
	* 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.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*
	* This driver is based on max8997.c
	*/

	#include <linux/export.h>
	#include <linux/slab.h>
	#include <linux/i2c.h>
	#include <linux/irq.h>
	#include <linux/interrupt.h>
	#include <linux/pm_runtime.h>
	#include <linux/module.h>
	#include <linux/mfd/core.h>
	#include <linux/mfd/max77686.h>
	#include <linux/mfd/max77686-private.h>
	#include <linux/err.h>
	#include <linux/of.h>

	#define I2C_ADDR_RTC (0x0C >> 1)

	static const struct mfd_cell max77686_devs[] = {
	{ .name = "max77686-pmic", },
	{ .name = "max77686-rtc", },
	{ .name = "max77686-clk", },
	};

	static const struct mfd_cell max77802_devs[] = {
	{ .name = "max77802-pmic", },
	{ .name = "max77802-clk", },
	{ .name = "max77802-rtc", },
	};

	static bool max77802_pmic_is_accessible_reg(struct device *dev,
	unsigned int reg)
	{
	return reg < MAX77802_REG_PMIC_END;
	}

	static bool max77802_rtc_is_accessible_reg(struct device *dev,
	unsigned int reg)
	{
	return (reg >= MAX77802_RTC_INT && reg < MAX77802_RTC_END);
	}

	static bool max77802_is_accessible_reg(struct device *dev, unsigned int reg)
	{
	return (max77802_pmic_is_accessible_reg(dev, reg) \|\|
	max77802_rtc_is_accessible_reg(dev, reg));
	}

	static bool max77802_pmic_is_precious_reg(struct device *dev, unsigned int reg)
	{
	return (reg == MAX77802_REG_INTSRC \|\| reg == MAX77802_REG_INT1 \|\|
	reg == MAX77802_REG_INT2);
	}

	static bool max77802_rtc_is_precious_reg(struct device *dev, unsigned int reg)
	{
	return (reg == MAX77802_RTC_INT \|\|
	reg == MAX77802_RTC_UPDATE0 \|\|
	reg == MAX77802_RTC_UPDATE1);
	}

	static bool max77802_is_precious_reg(struct device *dev, unsigned int reg)
	{
	return (max77802_pmic_is_precious_reg(dev, reg) \|\|
	max77802_rtc_is_precious_reg(dev, reg));
	}

	static bool max77802_pmic_is_volatile_reg(struct device *dev, unsigned int reg)
	{
	return (max77802_is_precious_reg(dev, reg) \|\|
	reg == MAX77802_REG_STATUS1 \|\| reg == MAX77802_REG_STATUS2 \|\|
	reg == MAX77802_REG_PWRON);
	}

	static bool max77802_rtc_is_volatile_reg(struct device *dev, unsigned int reg)
	{
	return (max77802_rtc_is_precious_reg(dev, reg) \|\|
	reg == MAX77802_RTC_SEC \|\|
	reg == MAX77802_RTC_MIN \|\|
	reg == MAX77802_RTC_HOUR \|\|
	reg == MAX77802_RTC_WEEKDAY \|\|
	reg == MAX77802_RTC_MONTH \|\|
	reg == MAX77802_RTC_YEAR \|\|
	reg == MAX77802_RTC_DATE);
	}

	static bool max77802_is_volatile_reg(struct device *dev, unsigned int reg)
	{
	return (max77802_pmic_is_volatile_reg(dev, reg) \|\|
	max77802_rtc_is_volatile_reg(dev, reg));
	}

	static const struct regmap_config max77686_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	};

	static const struct regmap_config max77686_rtc_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	};

	static const struct regmap_config max77802_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.writeable_reg = max77802_is_accessible_reg,
	.readable_reg = max77802_is_accessible_reg,
	.precious_reg = max77802_is_precious_reg,
	.volatile_reg = max77802_is_volatile_reg,
	.name = "max77802-pmic",
	.cache_type = REGCACHE_RBTREE,
	};

	static const struct regmap_irq max77686_irqs[] = {
	/* INT1 interrupts */
	{ .reg_offset = 0, .mask = MAX77686_INT1_PWRONF_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_INT1_PWRONR_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_INT1_JIGONBF_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_INT1_JIGONBR_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_INT1_ACOKBF_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_INT1_ACOKBR_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_INT1_ONKEY1S_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_INT1_MRSTB_MSK, },
	/* INT2 interrupts */
	{ .reg_offset = 1, .mask = MAX77686_INT2_140C_MSK, },
	{ .reg_offset = 1, .mask = MAX77686_INT2_120C_MSK, },
	};

	static const struct regmap_irq_chip max77686_irq_chip = {
	.name = "max77686-pmic",
	.status_base = MAX77686_REG_INT1,
	.mask_base = MAX77686_REG_INT1MSK,
	.num_regs = 2,
	.irqs = max77686_irqs,
	.num_irqs = ARRAY_SIZE(max77686_irqs),
	};

	static const struct regmap_irq max77686_rtc_irqs[] = {
	/* RTC interrupts */
	{ .reg_offset = 0, .mask = MAX77686_RTCINT_RTC60S_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_RTCINT_RTCA1_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_RTCINT_RTCA2_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_RTCINT_SMPL_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_RTCINT_RTC1S_MSK, },
	{ .reg_offset = 0, .mask = MAX77686_RTCINT_WTSR_MSK, },
	};

	static const struct regmap_irq_chip max77686_rtc_irq_chip = {
	.name = "max77686-rtc",
	.status_base = MAX77686_RTC_INT,
	.mask_base = MAX77686_RTC_INTM,
	.num_regs = 1,
	.irqs = max77686_rtc_irqs,
	.num_irqs = ARRAY_SIZE(max77686_rtc_irqs),
	};

	static const struct regmap_irq_chip max77802_irq_chip = {
	.name = "max77802-pmic",
	.status_base = MAX77802_REG_INT1,
	.mask_base = MAX77802_REG_INT1MSK,
	.num_regs = 2,
	.irqs = max77686_irqs, /* same masks as 77686 */
	.num_irqs = ARRAY_SIZE(max77686_irqs),
	};

	static const struct regmap_irq_chip max77802_rtc_irq_chip = {
	.name = "max77802-rtc",
	.status_base = MAX77802_RTC_INT,
	.mask_base = MAX77802_RTC_INTM,
	.num_regs = 1,
	.irqs = max77686_rtc_irqs, /* same masks as 77686 */
	.num_irqs = ARRAY_SIZE(max77686_rtc_irqs),
	};

	static const struct of_device_id max77686_pmic_dt_match[] = {
	{
	.compatible = "maxim,max77686",
	.data = (void *)TYPE_MAX77686,
	},
	{
	.compatible = "maxim,max77802",
	.data = (void *)TYPE_MAX77802,
	},
	{ },
	};

	static int max77686_i2c_probe(struct i2c_client *i2c,
	const struct i2c_device_id *id)
	{
	struct max77686_dev *max77686 = NULL;
	const struct of_device_id *match;
	unsigned int data;
	int ret = 0;
	const struct regmap_config *config;
	const struct regmap_irq_chip *irq_chip;
	const struct regmap_irq_chip *rtc_irq_chip;
	struct regmap **rtc_regmap;
	const struct mfd_cell *cells;
	int n_devs;

	max77686 = devm_kzalloc(&i2c->dev,
	sizeof(struct max77686_dev), GFP_KERNEL);
	if (!max77686)
	return -ENOMEM;

	if (i2c->dev.of_node) {
	match = of_match_node(max77686_pmic_dt_match, i2c->dev.of_node);
	if (!match)
	return -EINVAL;

	max77686->type = (unsigned long)match->data;
	} else
	max77686->type = id->driver_data;

	i2c_set_clientdata(i2c, max77686);
	max77686->dev = &i2c->dev;
	max77686->i2c = i2c;

	max77686->irq = i2c->irq;

	if (max77686->type == TYPE_MAX77686) {
	config = &max77686_regmap_config;
	irq_chip = &max77686_irq_chip;
	rtc_irq_chip = &max77686_rtc_irq_chip;
	rtc_regmap = &max77686->rtc_regmap;
	cells = max77686_devs;
	n_devs = ARRAY_SIZE(max77686_devs);
	} else {
	config = &max77802_regmap_config;
	irq_chip = &max77802_irq_chip;
	rtc_irq_chip = &max77802_rtc_irq_chip;
	rtc_regmap = &max77686->regmap;
	cells = max77802_devs;
	n_devs = ARRAY_SIZE(max77802_devs);
	}

	max77686->regmap = devm_regmap_init_i2c(i2c, config);
	if (IS_ERR(max77686->regmap)) {
	ret = PTR_ERR(max77686->regmap);
	dev_err(max77686->dev, "Failed to allocate register map: %d\n",
	ret);
	return ret;
	}

	ret = regmap_read(max77686->regmap, MAX77686_REG_DEVICE_ID, &data);
	if (ret < 0) {
	dev_err(max77686->dev,
	"device not found on this channel (this is not an error)\n");
	return -ENODEV;
	}

	if (max77686->type == TYPE_MAX77686) {
	max77686->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC);
	if (!max77686->rtc) {
	dev_err(max77686->dev,
	"Failed to allocate I2C device for RTC\n");
	return -ENODEV;
	}
	i2c_set_clientdata(max77686->rtc, max77686);

	max77686->rtc_regmap =
	devm_regmap_init_i2c(max77686->rtc,
	&max77686_rtc_regmap_config);
	if (IS_ERR(max77686->rtc_regmap)) {
	ret = PTR_ERR(max77686->rtc_regmap);
	dev_err(max77686->dev,
	"failed to allocate RTC regmap: %d\n",
	ret);
	goto err_unregister_i2c;
	}
	}

	ret = regmap_add_irq_chip(max77686->regmap, max77686->irq,
	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT \|
	IRQF_SHARED, 0, irq_chip,
	&max77686->irq_data);
	if (ret) {
	dev_err(&i2c->dev, "failed to add PMIC irq chip: %d\n", ret);
	goto err_unregister_i2c;
	}

	ret = regmap_add_irq_chip(*rtc_regmap, max77686->irq,
	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT \|
	IRQF_SHARED, 0, rtc_irq_chip,
	&max77686->rtc_irq_data);
	if (ret) {
	dev_err(&i2c->dev, "failed to add RTC irq chip: %d\n", ret);
	goto err_del_irqc;
	}

	ret = mfd_add_devices(max77686->dev, -1, cells, n_devs, NULL, 0, NULL);
	if (ret < 0) {
	dev_err(&i2c->dev, "failed to add MFD devices: %d\n", ret);
	goto err_del_rtc_irqc;
	}

	return 0;

	err_del_rtc_irqc:
	regmap_del_irq_chip(max77686->irq, max77686->rtc_irq_data);
	err_del_irqc:
	regmap_del_irq_chip(max77686->irq, max77686->irq_data);
	err_unregister_i2c:
	if (max77686->type == TYPE_MAX77686)
	i2c_unregister_device(max77686->rtc);

	return ret;
	}

	static int max77686_i2c_remove(struct i2c_client *i2c)
	{
	struct max77686_dev *max77686 = i2c_get_clientdata(i2c);

	mfd_remove_devices(max77686->dev);

	regmap_del_irq_chip(max77686->irq, max77686->rtc_irq_data);
	regmap_del_irq_chip(max77686->irq, max77686->irq_data);

	if (max77686->type == TYPE_MAX77686)
	i2c_unregister_device(max77686->rtc);

	return 0;
	}

	static const struct i2c_device_id max77686_i2c_id[] = {
	{ "max77686", TYPE_MAX77686 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, max77686_i2c_id);

	#ifdef CONFIG_PM_SLEEP
	static int max77686_suspend(struct device *dev)
	{
	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
	struct max77686_dev *max77686 = i2c_get_clientdata(i2c);

	if (device_may_wakeup(dev))
	enable_irq_wake(max77686->irq);

	/*
	* IRQ must be disabled during suspend because if it happens
	* while suspended it will be handled before resuming I2C.
	*
	* When device is woken up from suspend (e.g. by RTC wake alarm),
	* an interrupt occurs before resuming I2C bus controller.
	* Interrupt handler tries to read registers but this read
	* will fail because I2C is still suspended.
	*/
	disable_irq(max77686->irq);

	return 0;
	}

	static int max77686_resume(struct device *dev)
	{
	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
	struct max77686_dev *max77686 = i2c_get_clientdata(i2c);

	if (device_may_wakeup(dev))
	disable_irq_wake(max77686->irq);

	enable_irq(max77686->irq);

	return 0;
	}
	#endif /* CONFIG_PM_SLEEP */

	static SIMPLE_DEV_PM_OPS(max77686_pm, max77686_suspend, max77686_resume);

	static struct i2c_driver max77686_i2c_driver = {
	.driver = {
	.name = "max77686",
	.pm = &max77686_pm,
	.of_match_table = of_match_ptr(max77686_pmic_dt_match),
	},
	.probe = max77686_i2c_probe,
	.remove = max77686_i2c_remove,
	.id_table = max77686_i2c_id,
	};

	static int __init max77686_i2c_init(void)
	{
	return i2c_add_driver(&max77686_i2c_driver);
	}
	/* init early so consumer devices can complete system boot */
	subsys_initcall(max77686_i2c_init);

	static void __exit max77686_i2c_exit(void)
	{
	i2c_del_driver(&max77686_i2c_driver);
	}
	module_exit(max77686_i2c_exit);

	MODULE_DESCRIPTION("MAXIM 77686/802 multi-function core driver");
	MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
	MODULE_LICENSE("GPL");