/*

   * max77686.c - mfd core driver for the Maxim 77686/802

   *
   * Copyright (C) 2012 Samsung Electronics

   * Chiwoong Byun <woong.byun@samsung.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>

  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 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_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 of_device_id max77686_pmic_dt_match[] = {

  	{
  		.compatible = "maxim,max77686",
  		.data = (void *)TYPE_MAX77686,
  	},
  	{
  		.compatible = "maxim,max77802",
  		.data = (void *)TYPE_MAX77802,
  	},
  	{ },

  };

  MODULE_DEVICE_TABLE(of, max77686_pmic_dt_match);

  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 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;

  		cells =  max77686_devs;
  		n_devs = ARRAY_SIZE(max77686_devs);
  	} else {
  		config = &max77802_regmap_config;
  		irq_chip = &max77802_irq_chip;

  		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
  ",
  				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)
  ");

  		return -ENODEV;

  	}

  	ret = devm_regmap_add_irq_chip(&i2c->dev, max77686->regmap,
  				       max77686->irq,
  				       IRQF_TRIGGER_FALLING | IRQF_ONESHOT |
  				       IRQF_SHARED, 0, irq_chip,
  				       &max77686->irq_data);

  	if (ret < 0) {

  		dev_err(&i2c->dev, "failed to add PMIC irq chip: %d
  ", ret);

  		return ret;

  	}

  	ret = devm_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
  ", ret);

  		return ret;

  	}

  	return 0;

  }
  
  static const struct i2c_device_id max77686_i2c_id[] = {
  	{ "max77686", TYPE_MAX77686 },

  	{ "max77802", TYPE_MAX77802 },

  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, max77686_i2c_id);

  #ifdef CONFIG_PM_SLEEP
  static int max77686_suspend(struct device *dev)
  {

  	struct i2c_client *i2c = to_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 = to_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,

  	.id_table = max77686_i2c_id,
  };

  module_i2c_driver(max77686_i2c_driver);

  MODULE_DESCRIPTION("MAXIM 77686/802 multi-function core driver");

  MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
  MODULE_LICENSE("GPL");