/*
   * max8907.c - mfd driver for MAX8907
   *
   * Copyright (C) 2010 Gyungoh Yoo <jack.yoo@maxim-ic.com>
   * Copyright (C) 2010-2012, NVIDIA CORPORATION. All rights reserved.
   *
   * 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/err.h>
  #include <linux/i2c.h>
  #include <linux/init.h>
  #include <linux/interrupt.h>
  #include <linux/irq.h>
  #include <linux/mfd/core.h>
  #include <linux/mfd/max8907.h>
  #include <linux/module.h>
  #include <linux/of.h>
  #include <linux/of_device.h>
  #include <linux/regmap.h>
  #include <linux/slab.h>
  
  static const struct mfd_cell max8907_cells[] = {
  	{ .name = "max8907-regulator", },
  	{ .name = "max8907-rtc", },
  };
  
  static bool max8907_gen_is_volatile_reg(struct device *dev, unsigned int reg)
  {
  	switch (reg) {
  	case MAX8907_REG_ON_OFF_IRQ1:
  	case MAX8907_REG_ON_OFF_STAT:
  	case MAX8907_REG_ON_OFF_IRQ2:
  	case MAX8907_REG_CHG_IRQ1:
  	case MAX8907_REG_CHG_IRQ2:
  	case MAX8907_REG_CHG_STAT:
  		return true;
  	default:
  		return false;
  	}
  }
  
  static bool max8907_gen_is_precious_reg(struct device *dev, unsigned int reg)
  {
  	switch (reg) {
  	case MAX8907_REG_ON_OFF_IRQ1:
  	case MAX8907_REG_ON_OFF_IRQ2:
  	case MAX8907_REG_CHG_IRQ1:
  	case MAX8907_REG_CHG_IRQ2:
  		return true;
  	default:
  		return false;
  	}
  }
  
  static bool max8907_gen_is_writeable_reg(struct device *dev, unsigned int reg)
  {
  	return !max8907_gen_is_volatile_reg(dev, reg);
  }
  
  static const struct regmap_config max8907_regmap_gen_config = {
  	.reg_bits = 8,
  	.val_bits = 8,
  	.volatile_reg = max8907_gen_is_volatile_reg,
  	.precious_reg = max8907_gen_is_precious_reg,
  	.writeable_reg = max8907_gen_is_writeable_reg,
  	.max_register = MAX8907_REG_LDO20VOUT,
  	.cache_type = REGCACHE_RBTREE,
  };
  
  static bool max8907_rtc_is_volatile_reg(struct device *dev, unsigned int reg)
  {
  	if (reg <= MAX8907_REG_RTC_YEAR2)
  		return true;
  
  	switch (reg) {
  	case MAX8907_REG_RTC_STATUS:
  	case MAX8907_REG_RTC_IRQ:
  		return true;
  	default:
  		return false;
  	}
  }
  
  static bool max8907_rtc_is_precious_reg(struct device *dev, unsigned int reg)
  {
  	switch (reg) {
  	case MAX8907_REG_RTC_IRQ:
  		return true;
  	default:
  		return false;
  	}
  }
  
  static bool max8907_rtc_is_writeable_reg(struct device *dev, unsigned int reg)
  {
  	switch (reg) {
  	case MAX8907_REG_RTC_STATUS:
  	case MAX8907_REG_RTC_IRQ:
  		return false;
  	default:
  		return true;
  	}
  }
  
  static const struct regmap_config max8907_regmap_rtc_config = {
  	.reg_bits = 8,
  	.val_bits = 8,
  	.volatile_reg = max8907_rtc_is_volatile_reg,
  	.precious_reg = max8907_rtc_is_precious_reg,
  	.writeable_reg = max8907_rtc_is_writeable_reg,
  	.max_register = MAX8907_REG_MPL_CNTL,
  	.cache_type = REGCACHE_RBTREE,
  };
  
  static const struct regmap_irq max8907_chg_irqs[] = {
  	{ .reg_offset = 0, .mask = 1 << 0, },
  	{ .reg_offset = 0, .mask = 1 << 1, },
  	{ .reg_offset = 0, .mask = 1 << 2, },
  	{ .reg_offset = 1, .mask = 1 << 0, },
  	{ .reg_offset = 1, .mask = 1 << 1, },
  	{ .reg_offset = 1, .mask = 1 << 2, },
  	{ .reg_offset = 1, .mask = 1 << 3, },
  	{ .reg_offset = 1, .mask = 1 << 4, },
  	{ .reg_offset = 1, .mask = 1 << 5, },
  	{ .reg_offset = 1, .mask = 1 << 6, },
  	{ .reg_offset = 1, .mask = 1 << 7, },
  };
  
  static const struct regmap_irq_chip max8907_chg_irq_chip = {
  	.name = "max8907 chg",
  	.status_base = MAX8907_REG_CHG_IRQ1,
  	.mask_base = MAX8907_REG_CHG_IRQ1_MASK,
  	.wake_base = MAX8907_REG_CHG_IRQ1_MASK,
  	.irq_reg_stride = MAX8907_REG_CHG_IRQ2 - MAX8907_REG_CHG_IRQ1,
  	.num_regs = 2,
  	.irqs = max8907_chg_irqs,
  	.num_irqs = ARRAY_SIZE(max8907_chg_irqs),
  };
  
  static const struct regmap_irq max8907_on_off_irqs[] = {
  	{ .reg_offset = 0, .mask = 1 << 0, },
  	{ .reg_offset = 0, .mask = 1 << 1, },
  	{ .reg_offset = 0, .mask = 1 << 2, },
  	{ .reg_offset = 0, .mask = 1 << 3, },
  	{ .reg_offset = 0, .mask = 1 << 4, },
  	{ .reg_offset = 0, .mask = 1 << 5, },
  	{ .reg_offset = 0, .mask = 1 << 6, },
  	{ .reg_offset = 0, .mask = 1 << 7, },
  	{ .reg_offset = 1, .mask = 1 << 0, },
  	{ .reg_offset = 1, .mask = 1 << 1, },
  };
  
  static const struct regmap_irq_chip max8907_on_off_irq_chip = {
  	.name = "max8907 on_off",
  	.status_base = MAX8907_REG_ON_OFF_IRQ1,
  	.mask_base = MAX8907_REG_ON_OFF_IRQ1_MASK,
  	.irq_reg_stride = MAX8907_REG_ON_OFF_IRQ2 - MAX8907_REG_ON_OFF_IRQ1,
  	.num_regs = 2,
  	.irqs = max8907_on_off_irqs,
  	.num_irqs = ARRAY_SIZE(max8907_on_off_irqs),
  };
  
  static const struct regmap_irq max8907_rtc_irqs[] = {
  	{ .reg_offset = 0, .mask = 1 << 2, },
  	{ .reg_offset = 0, .mask = 1 << 3, },
  };
  
  static const struct regmap_irq_chip max8907_rtc_irq_chip = {
  	.name = "max8907 rtc",
  	.status_base = MAX8907_REG_RTC_IRQ,
  	.mask_base = MAX8907_REG_RTC_IRQ_MASK,
  	.num_regs = 1,
  	.irqs = max8907_rtc_irqs,
  	.num_irqs = ARRAY_SIZE(max8907_rtc_irqs),
  };
  
  static struct max8907 *max8907_pm_off;
  static void max8907_power_off(void)
  {
  	regmap_update_bits(max8907_pm_off->regmap_gen, MAX8907_REG_RESET_CNFG,
  			MAX8907_MASK_POWER_OFF, MAX8907_MASK_POWER_OFF);
  }
  
  static int max8907_i2c_probe(struct i2c_client *i2c,
  				       const struct i2c_device_id *id)
  {
  	struct max8907 *max8907;
  	int ret;
  	struct max8907_platform_data *pdata = dev_get_platdata(&i2c->dev);
  	bool pm_off = false;
  
  	if (pdata)
  		pm_off = pdata->pm_off;
  	else if (i2c->dev.of_node)
  		pm_off = of_property_read_bool(i2c->dev.of_node,
  					"maxim,system-power-controller");
  
  	max8907 = devm_kzalloc(&i2c->dev, sizeof(struct max8907), GFP_KERNEL);
  	if (!max8907) {
  		ret = -ENOMEM;
  		goto err_alloc_drvdata;
  	}
  
  	max8907->dev = &i2c->dev;
  	dev_set_drvdata(max8907->dev, max8907);
  
  	max8907->i2c_gen = i2c;
  	i2c_set_clientdata(i2c, max8907);
  	max8907->regmap_gen = devm_regmap_init_i2c(i2c,
  						&max8907_regmap_gen_config);
  	if (IS_ERR(max8907->regmap_gen)) {
  		ret = PTR_ERR(max8907->regmap_gen);
  		dev_err(&i2c->dev, "gen regmap init failed: %d
  ", ret);
  		goto err_regmap_gen;
  	}
  
  	max8907->i2c_rtc = i2c_new_dummy(i2c->adapter, MAX8907_RTC_I2C_ADDR);
  	if (!max8907->i2c_rtc) {
  		ret = -ENOMEM;
  		goto err_dummy_rtc;
  	}
  	i2c_set_clientdata(max8907->i2c_rtc, max8907);
  	max8907->regmap_rtc = devm_regmap_init_i2c(max8907->i2c_rtc,
  						&max8907_regmap_rtc_config);
  	if (IS_ERR(max8907->regmap_rtc)) {
  		ret = PTR_ERR(max8907->regmap_rtc);
  		dev_err(&i2c->dev, "rtc regmap init failed: %d
  ", ret);
  		goto err_regmap_rtc;
  	}
  
  	irq_set_status_flags(max8907->i2c_gen->irq, IRQ_NOAUTOEN);
  
  	ret = regmap_add_irq_chip(max8907->regmap_gen, max8907->i2c_gen->irq,
  				  IRQF_ONESHOT | IRQF_SHARED, -1,
  				  &max8907_chg_irq_chip,
  				  &max8907->irqc_chg);
  	if (ret != 0) {
  		dev_err(&i2c->dev, "failed to add chg irq chip: %d
  ", ret);
  		goto err_irqc_chg;
  	}
  	ret = regmap_add_irq_chip(max8907->regmap_gen, max8907->i2c_gen->irq,
  				  IRQF_ONESHOT | IRQF_SHARED, -1,
  				  &max8907_on_off_irq_chip,
  				  &max8907->irqc_on_off);
  	if (ret != 0) {
  		dev_err(&i2c->dev, "failed to add on off irq chip: %d
  ", ret);
  		goto err_irqc_on_off;
  	}
  	ret = regmap_add_irq_chip(max8907->regmap_rtc, max8907->i2c_gen->irq,
  				  IRQF_ONESHOT | IRQF_SHARED, -1,
  				  &max8907_rtc_irq_chip,
  				  &max8907->irqc_rtc);
  	if (ret != 0) {
  		dev_err(&i2c->dev, "failed to add rtc irq chip: %d
  ", ret);
  		goto err_irqc_rtc;
  	}
  
  	enable_irq(max8907->i2c_gen->irq);
  
  	ret = mfd_add_devices(max8907->dev, -1, max8907_cells,
  			      ARRAY_SIZE(max8907_cells), NULL, 0, NULL);
  	if (ret != 0) {
  		dev_err(&i2c->dev, "failed to add MFD devices %d
  ", ret);
  		goto err_add_devices;
  	}
  
  	if (pm_off && !pm_power_off) {
  		max8907_pm_off = max8907;
  		pm_power_off = max8907_power_off;
  	}
  
  	return 0;
  
  err_add_devices:
  	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_rtc);
  err_irqc_rtc:
  	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_on_off);
  err_irqc_on_off:
  	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_chg);
  err_irqc_chg:
  err_regmap_rtc:
  	i2c_unregister_device(max8907->i2c_rtc);
  err_dummy_rtc:
  err_regmap_gen:
  err_alloc_drvdata:
  	return ret;
  }
  
  static int max8907_i2c_remove(struct i2c_client *i2c)
  {
  	struct max8907 *max8907 = i2c_get_clientdata(i2c);
  
  	mfd_remove_devices(max8907->dev);
  
  	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_rtc);
  	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_on_off);
  	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_chg);
  
  	i2c_unregister_device(max8907->i2c_rtc);
  
  	return 0;
  }
  
  #ifdef CONFIG_OF
  static struct of_device_id max8907_of_match[] = {
  	{ .compatible = "maxim,max8907" },
  	{ },
  };
  MODULE_DEVICE_TABLE(of, max8907_of_match);
  #endif
  
  static const struct i2c_device_id max8907_i2c_id[] = {
  	{"max8907", 0},
  	{}
  };
  MODULE_DEVICE_TABLE(i2c, max8907_i2c_id);
  
  static struct i2c_driver max8907_i2c_driver = {
  	.driver = {
  		.name = "max8907",
  		.owner = THIS_MODULE,
  		.of_match_table = of_match_ptr(max8907_of_match),
  	},
  	.probe = max8907_i2c_probe,
  	.remove = max8907_i2c_remove,
  	.id_table = max8907_i2c_id,
  };
  
  static int __init max8907_i2c_init(void)
  {
  	int ret = -ENODEV;
  
  	ret = i2c_add_driver(&max8907_i2c_driver);
  	if (ret != 0)
  		pr_err("Failed to register I2C driver: %d
  ", ret);
  
  	return ret;
  }
  subsys_initcall(max8907_i2c_init);
  
  static void __exit max8907_i2c_exit(void)
  {
  	i2c_del_driver(&max8907_i2c_driver);
  }
  module_exit(max8907_i2c_exit);
  
  MODULE_DESCRIPTION("MAX8907 multi-function core driver");
  MODULE_AUTHOR("Gyungoh Yoo <jack.yoo@maxim-ic.com>");
  MODULE_LICENSE("GPL v2");