// SPDX-License-Identifier: GPL-2.0+
  //
  // max8998.c - mfd core driver for the Maxim 8998
  //
  //  Copyright (C) 2009-2010 Samsung Electronics
  //  Kyungmin Park <kyungmin.park@samsung.com>
  //  Marek Szyprowski <m.szyprowski@samsung.com>

  #include <linux/err.h>

  #include <linux/init.h>
  #include <linux/slab.h>
  #include <linux/i2c.h>

  #include <linux/interrupt.h>

  #include <linux/of.h>
  #include <linux/of_irq.h>

  #include <linux/pm_runtime.h>

  #include <linux/mutex.h>
  #include <linux/mfd/core.h>
  #include <linux/mfd/max8998.h>
  #include <linux/mfd/max8998-private.h>

  #define RTC_I2C_ADDR		(0x0c >> 1)

  static const struct mfd_cell max8998_devs[] = {

  	{
  		.name = "max8998-pmic",

  	}, {
  		.name = "max8998-rtc",

  	}, {
  		.name = "max8998-battery",

  	},

  };

  static const struct mfd_cell lp3974_devs[] = {

  	{
  		.name = "lp3974-pmic",
  	}, {
  		.name = "lp3974-rtc",
  	},
  };

  int max8998_read_reg(struct i2c_client *i2c, u8 reg, u8 *dest)

  {

  	struct max8998_dev *max8998 = i2c_get_clientdata(i2c);

  	int ret;
  
  	mutex_lock(&max8998->iolock);

  	ret = i2c_smbus_read_byte_data(i2c, reg);

  	mutex_unlock(&max8998->iolock);
  	if (ret < 0)
  		return ret;
  
  	ret &= 0xff;
  	*dest = ret;
  	return 0;
  }

  EXPORT_SYMBOL(max8998_read_reg);

  int max8998_bulk_read(struct i2c_client *i2c, u8 reg, int count, u8 *buf)
  {
  	struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
  	int ret;
  
  	mutex_lock(&max8998->iolock);
  	ret = i2c_smbus_read_i2c_block_data(i2c, reg, count, buf);
  	mutex_unlock(&max8998->iolock);
  	if (ret < 0)
  		return ret;
  
  	return 0;
  }
  EXPORT_SYMBOL(max8998_bulk_read);

  int max8998_write_reg(struct i2c_client *i2c, u8 reg, u8 value)

  {

  	struct max8998_dev *max8998 = i2c_get_clientdata(i2c);

  	int ret;
  
  	mutex_lock(&max8998->iolock);

  	ret = i2c_smbus_write_byte_data(i2c, reg, value);

  	mutex_unlock(&max8998->iolock);
  	return ret;
  }

  EXPORT_SYMBOL(max8998_write_reg);

  int max8998_bulk_write(struct i2c_client *i2c, u8 reg, int count, u8 *buf)
  {
  	struct max8998_dev *max8998 = i2c_get_clientdata(i2c);
  	int ret;
  
  	mutex_lock(&max8998->iolock);
  	ret = i2c_smbus_write_i2c_block_data(i2c, reg, count, buf);
  	mutex_unlock(&max8998->iolock);
  	if (ret < 0)
  		return ret;
  
  	return 0;
  }
  EXPORT_SYMBOL(max8998_bulk_write);

  int max8998_update_reg(struct i2c_client *i2c, u8 reg, u8 val, u8 mask)

  {

  	struct max8998_dev *max8998 = i2c_get_clientdata(i2c);

  	int ret;
  
  	mutex_lock(&max8998->iolock);

  	ret = i2c_smbus_read_byte_data(i2c, reg);

  	if (ret >= 0) {
  		u8 old_val = ret & 0xff;
  		u8 new_val = (val & mask) | (old_val & (~mask));

  		ret = i2c_smbus_write_byte_data(i2c, reg, new_val);

  	}
  	mutex_unlock(&max8998->iolock);
  	return ret;
  }

  EXPORT_SYMBOL(max8998_update_reg);

  #ifdef CONFIG_OF

  static const struct of_device_id max8998_dt_match[] = {

  	{ .compatible = "maxim,max8998", .data = (void *)TYPE_MAX8998 },
  	{ .compatible = "national,lp3974", .data = (void *)TYPE_LP3974 },
  	{ .compatible = "ti,lp3974", .data = (void *)TYPE_LP3974 },
  	{},
  };

  #endif
  
  /*
   * Only the common platform data elements for max8998 are parsed here from the
   * device tree. Other sub-modules of max8998 such as pmic, rtc and others have
   * to parse their own platform data elements from device tree.
   *
   * The max8998 platform data structure is instantiated here and the drivers for
   * the sub-modules need not instantiate another instance while parsing their
   * platform data.
   */
  static struct max8998_platform_data *max8998_i2c_parse_dt_pdata(
  							struct device *dev)
  {
  	struct max8998_platform_data *pd;
  
  	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
  	if (!pd)
  		return ERR_PTR(-ENOMEM);
  
  	pd->ono = irq_of_parse_and_map(dev->of_node, 1);
  
  	/*
  	 * ToDo: the 'wakeup' member in the platform data is more of a linux
  	 * specfic information. Hence, there is no binding for that yet and
  	 * not parsed here.
  	 */
  	return pd;
  }

  static inline unsigned long max8998_i2c_get_driver_data(struct i2c_client *i2c,

  						const struct i2c_device_id *id)
  {
  	if (IS_ENABLED(CONFIG_OF) && i2c->dev.of_node) {
  		const struct of_device_id *match;
  		match = of_match_node(max8998_dt_match, i2c->dev.of_node);

  		return (unsigned long)match->data;

  	}

  	return id->driver_data;

  }

  static int max8998_i2c_probe(struct i2c_client *i2c,
  			    const struct i2c_device_id *id)
  {

  	struct max8998_platform_data *pdata = dev_get_platdata(&i2c->dev);

  	struct max8998_dev *max8998;
  	int ret = 0;

  	max8998 = devm_kzalloc(&i2c->dev, sizeof(struct max8998_dev),
  				GFP_KERNEL);

  	if (max8998 == NULL)

  		return -ENOMEM;

  	if (IS_ENABLED(CONFIG_OF) && i2c->dev.of_node) {
  		pdata = max8998_i2c_parse_dt_pdata(&i2c->dev);

  		if (IS_ERR(pdata))
  			return PTR_ERR(pdata);

  	}

  	i2c_set_clientdata(i2c, max8998);
  	max8998->dev = &i2c->dev;

  	max8998->i2c = i2c;

  	max8998->irq = i2c->irq;

  	max8998->type = max8998_i2c_get_driver_data(i2c, id);
  	max8998->pdata = pdata;

  	if (pdata) {
  		max8998->ono = pdata->ono;
  		max8998->irq_base = pdata->irq_base;

  		max8998->wakeup = pdata->wakeup;

  	}

  	mutex_init(&max8998->iolock);

  	max8998->rtc = i2c_new_dummy_device(i2c->adapter, RTC_I2C_ADDR);
  	if (IS_ERR(max8998->rtc)) {

  		dev_err(&i2c->dev, "Failed to allocate I2C device for RTC
  ");

  		return PTR_ERR(max8998->rtc);

  	}

  	i2c_set_clientdata(max8998->rtc, max8998);

  	max8998_irq_init(max8998);

  	pm_runtime_set_active(max8998->dev);

  	switch (max8998->type) {

  	case TYPE_LP3974:
  		ret = mfd_add_devices(max8998->dev, -1,

  				      lp3974_devs, ARRAY_SIZE(lp3974_devs),
  				      NULL, 0, NULL);

  		break;
  	case TYPE_MAX8998:
  		ret = mfd_add_devices(max8998->dev, -1,

  				      max8998_devs, ARRAY_SIZE(max8998_devs),
  				      NULL, 0, NULL);

  		break;
  	default:
  		ret = -EINVAL;
  	}

  	if (ret < 0)
  		goto err;

  	device_init_wakeup(max8998->dev, max8998->wakeup);

  	return ret;
  
  err:
  	mfd_remove_devices(max8998->dev);

  	max8998_irq_exit(max8998);
  	i2c_unregister_device(max8998->rtc);

  	return ret;
  }

  static const struct i2c_device_id max8998_i2c_id[] = {

  	{ "max8998", TYPE_MAX8998 },
  	{ "lp3974", TYPE_LP3974},

  	{ }

  };

  static int max8998_suspend(struct device *dev)
  {

  	struct i2c_client *i2c = to_i2c_client(dev);

  	struct max8998_dev *max8998 = i2c_get_clientdata(i2c);

  	if (device_may_wakeup(dev))

  		irq_set_irq_wake(max8998->irq, 1);

  	return 0;
  }
  
  static int max8998_resume(struct device *dev)
  {

  	struct i2c_client *i2c = to_i2c_client(dev);

  	struct max8998_dev *max8998 = i2c_get_clientdata(i2c);

  	if (device_may_wakeup(dev))

  		irq_set_irq_wake(max8998->irq, 0);

  	/*
  	 * In LP3974, if IRQ registers are not "read & clear"
  	 * when it's set during sleep, the interrupt becomes
  	 * disabled.
  	 */
  	return max8998_irq_resume(i2c_get_clientdata(i2c));
  }
  
  struct max8998_reg_dump {
  	u8	addr;
  	u8	val;
  };
  #define SAVE_ITEM(x)	{ .addr = (x), .val = 0x0, }

  static struct max8998_reg_dump max8998_dump[] = {

  	SAVE_ITEM(MAX8998_REG_IRQM1),
  	SAVE_ITEM(MAX8998_REG_IRQM2),
  	SAVE_ITEM(MAX8998_REG_IRQM3),
  	SAVE_ITEM(MAX8998_REG_IRQM4),
  	SAVE_ITEM(MAX8998_REG_STATUSM1),
  	SAVE_ITEM(MAX8998_REG_STATUSM2),
  	SAVE_ITEM(MAX8998_REG_CHGR1),
  	SAVE_ITEM(MAX8998_REG_CHGR2),
  	SAVE_ITEM(MAX8998_REG_LDO_ACTIVE_DISCHARGE1),
  	SAVE_ITEM(MAX8998_REG_LDO_ACTIVE_DISCHARGE1),
  	SAVE_ITEM(MAX8998_REG_BUCK_ACTIVE_DISCHARGE3),
  	SAVE_ITEM(MAX8998_REG_ONOFF1),
  	SAVE_ITEM(MAX8998_REG_ONOFF2),
  	SAVE_ITEM(MAX8998_REG_ONOFF3),
  	SAVE_ITEM(MAX8998_REG_ONOFF4),
  	SAVE_ITEM(MAX8998_REG_BUCK1_VOLTAGE1),
  	SAVE_ITEM(MAX8998_REG_BUCK1_VOLTAGE2),
  	SAVE_ITEM(MAX8998_REG_BUCK1_VOLTAGE3),
  	SAVE_ITEM(MAX8998_REG_BUCK1_VOLTAGE4),
  	SAVE_ITEM(MAX8998_REG_BUCK2_VOLTAGE1),
  	SAVE_ITEM(MAX8998_REG_BUCK2_VOLTAGE2),
  	SAVE_ITEM(MAX8998_REG_LDO2_LDO3),
  	SAVE_ITEM(MAX8998_REG_LDO4),
  	SAVE_ITEM(MAX8998_REG_LDO5),
  	SAVE_ITEM(MAX8998_REG_LDO6),
  	SAVE_ITEM(MAX8998_REG_LDO7),
  	SAVE_ITEM(MAX8998_REG_LDO8_LDO9),
  	SAVE_ITEM(MAX8998_REG_LDO10_LDO11),
  	SAVE_ITEM(MAX8998_REG_LDO12),
  	SAVE_ITEM(MAX8998_REG_LDO13),
  	SAVE_ITEM(MAX8998_REG_LDO14),
  	SAVE_ITEM(MAX8998_REG_LDO15),
  	SAVE_ITEM(MAX8998_REG_LDO16),
  	SAVE_ITEM(MAX8998_REG_LDO17),
  	SAVE_ITEM(MAX8998_REG_BKCHR),
  	SAVE_ITEM(MAX8998_REG_LBCNFG1),
  	SAVE_ITEM(MAX8998_REG_LBCNFG2),
  };
  /* Save registers before hibernation */
  static int max8998_freeze(struct device *dev)
  {

  	struct i2c_client *i2c = to_i2c_client(dev);

  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(max8998_dump); i++)
  		max8998_read_reg(i2c, max8998_dump[i].addr,
  				&max8998_dump[i].val);
  
  	return 0;
  }
  
  /* Restore registers after hibernation */
  static int max8998_restore(struct device *dev)
  {

  	struct i2c_client *i2c = to_i2c_client(dev);

  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(max8998_dump); i++)
  		max8998_write_reg(i2c, max8998_dump[i].addr,
  				max8998_dump[i].val);
  
  	return 0;
  }

  static const struct dev_pm_ops max8998_pm = {

  	.suspend = max8998_suspend,
  	.resume = max8998_resume,
  	.freeze = max8998_freeze,
  	.restore = max8998_restore,
  };

  static struct i2c_driver max8998_i2c_driver = {
  	.driver = {
  		   .name = "max8998",

  		   .pm = &max8998_pm,

  		   .suppress_bind_attrs = true,

  		   .of_match_table = of_match_ptr(max8998_dt_match),

  	},
  	.probe = max8998_i2c_probe,

  	.id_table = max8998_i2c_id,
  };
  
  static int __init max8998_i2c_init(void)
  {
  	return i2c_add_driver(&max8998_i2c_driver);
  }
  /* init early so consumer devices can complete system boot */
  subsys_initcall(max8998_i2c_init);