/*
   * max14577.c - mfd core driver for the Maxim 14577
   *
   * Copyright (C) 2013 Samsung Electrnoics
   * Chanwoo Choi <cw00.choi@samsung.com>
   * Krzysztof Kozlowski <k.kozlowski@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.
   *
   * This driver is based on max8997.c
   */
  
  #include <linux/module.h>
  #include <linux/interrupt.h>
  #include <linux/mfd/core.h>
  #include <linux/mfd/max14577.h>
  #include <linux/mfd/max14577-private.h>
  
  static struct mfd_cell max14577_devs[] = {
  	{ .name = "max14577-muic", },
  	{
  		.name = "max14577-regulator",
  		.of_compatible = "maxim,max14577-regulator",
  	},
  	{ .name = "max14577-charger", },
  };
  
  static bool max14577_volatile_reg(struct device *dev, unsigned int reg)
  {
  	switch (reg) {
  	case MAX14577_REG_INT1 ... MAX14577_REG_STATUS3:
  		return true;
  	default:
  		break;
  	}
  	return false;
  }
  
  static const struct regmap_config max14577_regmap_config = {
  	.reg_bits	= 8,
  	.val_bits	= 8,
  	.volatile_reg	= max14577_volatile_reg,
  	.max_register	= MAX14577_REG_END,
  };
  
  static const struct regmap_irq max14577_irqs[] = {
  	/* INT1 interrupts */
  	{ .reg_offset = 0, .mask = INT1_ADC_MASK, },
  	{ .reg_offset = 0, .mask = INT1_ADCLOW_MASK, },
  	{ .reg_offset = 0, .mask = INT1_ADCERR_MASK, },
  	/* INT2 interrupts */
  	{ .reg_offset = 1, .mask = INT2_CHGTYP_MASK, },
  	{ .reg_offset = 1, .mask = INT2_CHGDETRUN_MASK, },
  	{ .reg_offset = 1, .mask = INT2_DCDTMR_MASK, },
  	{ .reg_offset = 1, .mask = INT2_DBCHG_MASK, },
  	{ .reg_offset = 1, .mask = INT2_VBVOLT_MASK, },
  	/* INT3 interrupts */
  	{ .reg_offset = 2, .mask = INT3_EOC_MASK, },
  	{ .reg_offset = 2, .mask = INT3_CGMBC_MASK, },
  	{ .reg_offset = 2, .mask = INT3_OVP_MASK, },
  	{ .reg_offset = 2, .mask = INT3_MBCCHGERR_MASK, },
  };
  
  static const struct regmap_irq_chip max14577_irq_chip = {
  	.name			= "max14577",
  	.status_base		= MAX14577_REG_INT1,
  	.mask_base		= MAX14577_REG_INTMASK1,
  	.mask_invert		= 1,
  	.num_regs		= 3,
  	.irqs			= max14577_irqs,
  	.num_irqs		= ARRAY_SIZE(max14577_irqs),
  };
  
  static int max14577_i2c_probe(struct i2c_client *i2c,
  			      const struct i2c_device_id *id)
  {
  	struct max14577 *max14577;
  	struct max14577_platform_data *pdata = dev_get_platdata(&i2c->dev);
  	struct device_node *np = i2c->dev.of_node;
  	u8 reg_data;
  	int ret = 0;
  
  	if (np) {
  		pdata = devm_kzalloc(&i2c->dev, sizeof(*pdata), GFP_KERNEL);
  		if (!pdata)
  			return -ENOMEM;
  		i2c->dev.platform_data = pdata;
  	}
  
  	if (!pdata) {
  		dev_err(&i2c->dev, "No platform data found.
  ");
  		return -EINVAL;
  	}
  
  	max14577 = devm_kzalloc(&i2c->dev, sizeof(*max14577), GFP_KERNEL);
  	if (!max14577)
  		return -ENOMEM;
  
  	i2c_set_clientdata(i2c, max14577);
  	max14577->dev = &i2c->dev;
  	max14577->i2c = i2c;
  	max14577->irq = i2c->irq;
  
  	max14577->regmap = devm_regmap_init_i2c(i2c, &max14577_regmap_config);
  	if (IS_ERR(max14577->regmap)) {
  		ret = PTR_ERR(max14577->regmap);
  		dev_err(max14577->dev, "Failed to allocate register map: %d
  ",
  				ret);
  		return ret;
  	}
  
  	ret = max14577_read_reg(max14577->regmap, MAX14577_REG_DEVICEID,
  			&reg_data);
  	if (ret) {
  		dev_err(max14577->dev, "Device not found on this channel: %d
  ",
  				ret);
  		return ret;
  	}
  	max14577->vendor_id = ((reg_data & DEVID_VENDORID_MASK) >>
  				DEVID_VENDORID_SHIFT);
  	max14577->device_id = ((reg_data & DEVID_DEVICEID_MASK) >>
  				DEVID_DEVICEID_SHIFT);
  	dev_info(max14577->dev, "Device ID: 0x%x, vendor: 0x%x
  ",
  			max14577->device_id, max14577->vendor_id);
  
  	ret = regmap_add_irq_chip(max14577->regmap, max14577->irq,
  				  IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 0,
  				  &max14577_irq_chip,
  				  &max14577->irq_data);
  	if (ret != 0) {
  		dev_err(&i2c->dev, "Failed to request IRQ %d: %d
  ",
  				max14577->irq, ret);
  		return ret;
  	}
  
  	ret = mfd_add_devices(max14577->dev, -1, max14577_devs,
  			ARRAY_SIZE(max14577_devs), NULL, 0,
  			regmap_irq_get_domain(max14577->irq_data));
  	if (ret < 0)
  		goto err_mfd;
  
  	device_init_wakeup(max14577->dev, 1);
  
  	return 0;
  
  err_mfd:
  	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
  
  	return ret;
  }
  
  static int max14577_i2c_remove(struct i2c_client *i2c)
  {
  	struct max14577 *max14577 = i2c_get_clientdata(i2c);
  
  	mfd_remove_devices(max14577->dev);
  	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
  
  	return 0;
  }
  
  static const struct i2c_device_id max14577_i2c_id[] = {
  	{ "max14577", 0 },
  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, max14577_i2c_id);
  
  #ifdef CONFIG_PM_SLEEP
  static int max14577_suspend(struct device *dev)
  {
  	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
  	struct max14577 *max14577 = i2c_get_clientdata(i2c);
  
  	if (device_may_wakeup(dev)) {
  		enable_irq_wake(max14577->irq);
  		/*
  		 * MUIC IRQ must be disabled during suspend if this is
  		 * a wake up source because it will be handled before
  		 * resuming I2C.
  		 *
  		 * When device is woken up from suspend (e.g. by ADC change),
  		 * 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(max14577->irq);
  	}
  
  	return 0;
  }
  
  static int max14577_resume(struct device *dev)
  {
  	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
  	struct max14577 *max14577 = i2c_get_clientdata(i2c);
  
  	if (device_may_wakeup(dev)) {
  		disable_irq_wake(max14577->irq);
  		enable_irq(max14577->irq);
  	}
  
  	return 0;
  }
  #endif /* CONFIG_PM_SLEEP */
  
  static struct of_device_id max14577_dt_match[] = {
  	{ .compatible = "maxim,max14577", },
  	{},
  };
  
  static SIMPLE_DEV_PM_OPS(max14577_pm, max14577_suspend, max14577_resume);
  
  static struct i2c_driver max14577_i2c_driver = {
  	.driver = {
  		.name = "max14577",
  		.owner = THIS_MODULE,
  		.pm = &max14577_pm,
  		.of_match_table = max14577_dt_match,
  	},
  	.probe = max14577_i2c_probe,
  	.remove = max14577_i2c_remove,
  	.id_table = max14577_i2c_id,
  };
  
  static int __init max14577_i2c_init(void)
  {
  	return i2c_add_driver(&max14577_i2c_driver);
  }
  subsys_initcall(max14577_i2c_init);
  
  static void __exit max14577_i2c_exit(void)
  {
  	i2c_del_driver(&max14577_i2c_driver);
  }
  module_exit(max14577_i2c_exit);
  
  MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>, Krzysztof Kozlowski <k.kozlowski@samsung.com>");
  MODULE_DESCRIPTION("MAXIM 14577 multi-function core driver");
  MODULE_LICENSE("GPL");