// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Copyright (C) ST-Ericsson SA 2010
   *

   * Author: Hanumath Prasad <hanumath.prasad@stericsson.com> for ST-Ericsson
   * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
   */
  
  #include <linux/module.h>
  #include <linux/interrupt.h>
  #include <linux/irq.h>

  #include <linux/irqdomain.h>

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

  #include <linux/of.h>

  #include <linux/of_device.h>

  #include <linux/mfd/core.h>

  #include <linux/mfd/tc3589x.h>

  #include <linux/err.h>

  /**
   * enum tc3589x_version - indicates the TC3589x version
   */
  enum tc3589x_version {
  	TC3589X_TC35890,
  	TC3589X_TC35892,
  	TC3589X_TC35893,
  	TC3589X_TC35894,
  	TC3589X_TC35895,
  	TC3589X_TC35896,
  	TC3589X_UNKNOWN,
  };

  #define TC3589x_CLKMODE_MODCTL_SLEEP		0x0
  #define TC3589x_CLKMODE_MODCTL_OPERATION	(1 << 0)

  /**

   * tc3589x_reg_read() - read a single TC3589x register
   * @tc3589x:	Device to read from

   * @reg:	Register to read
   */

  int tc3589x_reg_read(struct tc3589x *tc3589x, u8 reg)

  {
  	int ret;

  	ret = i2c_smbus_read_byte_data(tc3589x->i2c, reg);

  	if (ret < 0)

  		dev_err(tc3589x->dev, "failed to read reg %#x: %d
  ",

  			reg, ret);
  
  	return ret;
  }

  EXPORT_SYMBOL_GPL(tc3589x_reg_read);

  
  /**

   * tc3589x_reg_write() - write a single TC3589x register

   * @tc3589x:	Device to write to

   * @reg:	Register to read
   * @data:	Value to write
   */

  int tc3589x_reg_write(struct tc3589x *tc3589x, u8 reg, u8 data)

  {
  	int ret;

  	ret = i2c_smbus_write_byte_data(tc3589x->i2c, reg, data);

  	if (ret < 0)

  		dev_err(tc3589x->dev, "failed to write reg %#x: %d
  ",

  			reg, ret);
  
  	return ret;
  }

  EXPORT_SYMBOL_GPL(tc3589x_reg_write);

  
  /**

   * tc3589x_block_read() - read multiple TC3589x registers
   * @tc3589x:	Device to read from

   * @reg:	First register
   * @length:	Number of registers
   * @values:	Buffer to write to
   */

  int tc3589x_block_read(struct tc3589x *tc3589x, u8 reg, u8 length, u8 *values)

  {
  	int ret;

  	ret = i2c_smbus_read_i2c_block_data(tc3589x->i2c, reg, length, values);

  	if (ret < 0)

  		dev_err(tc3589x->dev, "failed to read regs %#x: %d
  ",

  			reg, ret);
  
  	return ret;
  }

  EXPORT_SYMBOL_GPL(tc3589x_block_read);

  
  /**

   * tc3589x_block_write() - write multiple TC3589x registers
   * @tc3589x:	Device to write to

   * @reg:	First register
   * @length:	Number of registers
   * @values:	Values to write
   */

  int tc3589x_block_write(struct tc3589x *tc3589x, u8 reg, u8 length,

  			const u8 *values)
  {
  	int ret;

  	ret = i2c_smbus_write_i2c_block_data(tc3589x->i2c, reg, length,

  					     values);
  	if (ret < 0)

  		dev_err(tc3589x->dev, "failed to write regs %#x: %d
  ",

  			reg, ret);
  
  	return ret;
  }

  EXPORT_SYMBOL_GPL(tc3589x_block_write);

  
  /**

   * tc3589x_set_bits() - set the value of a bitfield in a TC3589x register
   * @tc3589x:	Device to write to

   * @reg:	Register to write
   * @mask:	Mask of bits to set

   * @val:	Value to set

   */

  int tc3589x_set_bits(struct tc3589x *tc3589x, u8 reg, u8 mask, u8 val)

  {
  	int ret;

  	mutex_lock(&tc3589x->lock);

  	ret = tc3589x_reg_read(tc3589x, reg);

  	if (ret < 0)
  		goto out;
  
  	ret &= ~mask;
  	ret |= val;

  	ret = tc3589x_reg_write(tc3589x, reg, ret);

  
  out:

  	mutex_unlock(&tc3589x->lock);

  	return ret;
  }

  EXPORT_SYMBOL_GPL(tc3589x_set_bits);

  
  static struct resource gpio_resources[] = {
  	{

  		.start	= TC3589x_INT_GPIIRQ,
  		.end	= TC3589x_INT_GPIIRQ,

  		.flags	= IORESOURCE_IRQ,
  	},
  };

  static struct resource keypad_resources[] = {
  	{
  		.start  = TC3589x_INT_KBDIRQ,
  		.end    = TC3589x_INT_KBDIRQ,
  		.flags  = IORESOURCE_IRQ,
  	},
  };

  static const struct mfd_cell tc3589x_dev_gpio[] = {

  	{

  		.name		= "tc3589x-gpio",

  		.num_resources	= ARRAY_SIZE(gpio_resources),
  		.resources	= &gpio_resources[0],

  		.of_compatible	= "toshiba,tc3589x-gpio",

  	},
  };

  static const struct mfd_cell tc3589x_dev_keypad[] = {

  	{
  		.name           = "tc3589x-keypad",
  		.num_resources  = ARRAY_SIZE(keypad_resources),
  		.resources      = &keypad_resources[0],

  		.of_compatible	= "toshiba,tc3589x-keypad",

  	},
  };

  static irqreturn_t tc3589x_irq(int irq, void *data)

  {

  	struct tc3589x *tc3589x = data;

  	int status;

  again:

  	status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);

  	if (status < 0)
  		return IRQ_NONE;
  
  	while (status) {
  		int bit = __ffs(status);

  		int virq = irq_create_mapping(tc3589x->domain, bit);

  		handle_nested_irq(virq);

  		status &= ~(1 << bit);
  	}
  
  	/*
  	 * A dummy read or write (to any register) appears to be necessary to
  	 * have the last interrupt clear (for example, GPIO IC write) take

  	 * effect. In such a case, recheck for any interrupt which is still
  	 * pending.

  	 */

  	status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
  	if (status)
  		goto again;

  
  	return IRQ_HANDLED;
  }

  static int tc3589x_irq_map(struct irq_domain *d, unsigned int virq,
  				irq_hw_number_t hwirq)

  {

  	struct tc3589x *tc3589x = d->host_data;

  	irq_set_chip_data(virq, tc3589x);
  	irq_set_chip_and_handler(virq, &dummy_irq_chip,
  				handle_edge_irq);
  	irq_set_nested_thread(virq, 1);

  	irq_set_noprobe(virq);

  
  	return 0;
  }

  static void tc3589x_irq_unmap(struct irq_domain *d, unsigned int virq)

  {

  	irq_set_chip_and_handler(virq, NULL, NULL);
  	irq_set_chip_data(virq, NULL);
  }

  static const struct irq_domain_ops tc3589x_irq_ops = {

  	.map    = tc3589x_irq_map,

  	.unmap  = tc3589x_irq_unmap,

  	.xlate  = irq_domain_xlate_onecell,

  };

  static int tc3589x_irq_init(struct tc3589x *tc3589x, struct device_node *np)

  {

  	tc3589x->domain = irq_domain_add_simple(

  		np, TC3589x_NR_INTERNAL_IRQS, 0,

  		&tc3589x_irq_ops, tc3589x);

  
  	if (!tc3589x->domain) {
  		dev_err(tc3589x->dev, "Failed to create irqdomain
  ");
  		return -ENOSYS;
  	}
  
  	return 0;

  }

  static int tc3589x_chip_init(struct tc3589x *tc3589x)

  {
  	int manf, ver, ret;

  	manf = tc3589x_reg_read(tc3589x, TC3589x_MANFCODE);

  	if (manf < 0)
  		return manf;

  	ver = tc3589x_reg_read(tc3589x, TC3589x_VERSION);

  	if (ver < 0)
  		return ver;

  	if (manf != TC3589x_MANFCODE_MAGIC) {
  		dev_err(tc3589x->dev, "unknown manufacturer: %#x
  ", manf);

  		return -EINVAL;
  	}

  	dev_info(tc3589x->dev, "manufacturer: %#x, version: %#x
  ", manf, ver);

  	/*
  	 * Put everything except the IRQ module into reset;
  	 * also spare the GPIO module for any pin initialization
  	 * done during pre-kernel boot
  	 */

  	ret = tc3589x_reg_write(tc3589x, TC3589x_RSTCTRL,
  				TC3589x_RSTCTRL_TIMRST
  				| TC3589x_RSTCTRL_ROTRST

  				| TC3589x_RSTCTRL_KBDRST);

  	if (ret < 0)
  		return ret;
  
  	/* Clear the reset interrupt. */

  	return tc3589x_reg_write(tc3589x, TC3589x_RSTINTCLR, 0x1);

  }

  static int tc3589x_device_init(struct tc3589x *tc3589x)

  {
  	int ret = 0;
  	unsigned int blocks = tc3589x->pdata->block;
  
  	if (blocks & TC3589x_BLOCK_GPIO) {
  		ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_gpio,

  				      ARRAY_SIZE(tc3589x_dev_gpio), NULL,

  				      0, tc3589x->domain);

  		if (ret) {
  			dev_err(tc3589x->dev, "failed to add gpio child
  ");
  			return ret;
  		}
  		dev_info(tc3589x->dev, "added gpio block
  ");
  	}

  	if (blocks & TC3589x_BLOCK_KEYPAD) {
  		ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_keypad,

  				      ARRAY_SIZE(tc3589x_dev_keypad), NULL,

  				      0, tc3589x->domain);

  		if (ret) {
  			dev_err(tc3589x->dev, "failed to keypad child
  ");
  			return ret;
  		}
  		dev_info(tc3589x->dev, "added keypad block
  ");
  	}

  	return ret;

  }

  static const struct of_device_id tc3589x_match[] = {
  	/* Legacy compatible string */
  	{ .compatible = "tc3589x", .data = (void *) TC3589X_UNKNOWN },
  	{ .compatible = "toshiba,tc35890", .data = (void *) TC3589X_TC35890 },
  	{ .compatible = "toshiba,tc35892", .data = (void *) TC3589X_TC35892 },
  	{ .compatible = "toshiba,tc35893", .data = (void *) TC3589X_TC35893 },
  	{ .compatible = "toshiba,tc35894", .data = (void *) TC3589X_TC35894 },
  	{ .compatible = "toshiba,tc35895", .data = (void *) TC3589X_TC35895 },
  	{ .compatible = "toshiba,tc35896", .data = (void *) TC3589X_TC35896 },
  	{ }
  };
  
  MODULE_DEVICE_TABLE(of, tc3589x_match);
  
  static struct tc3589x_platform_data *
  tc3589x_of_probe(struct device *dev, enum tc3589x_version *version)

  {

  	struct device_node *np = dev->of_node;
  	struct tc3589x_platform_data *pdata;

  	struct device_node *child;

  	const struct of_device_id *of_id;
  
  	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
  	if (!pdata)
  		return ERR_PTR(-ENOMEM);
  
  	of_id = of_match_device(tc3589x_match, dev);
  	if (!of_id)
  		return ERR_PTR(-ENODEV);
  	*version = (enum tc3589x_version) of_id->data;

  
  	for_each_child_of_node(np, child) {

  		if (of_device_is_compatible(child, "toshiba,tc3589x-gpio"))

  			pdata->block |= TC3589x_BLOCK_GPIO;

  		if (of_device_is_compatible(child, "toshiba,tc3589x-keypad"))

  			pdata->block |= TC3589x_BLOCK_KEYPAD;

  	}

  	return pdata;

  }

  static int tc3589x_probe(struct i2c_client *i2c,

  				   const struct i2c_device_id *id)
  {

  	struct device_node *np = i2c->dev.of_node;

  	struct tc3589x_platform_data *pdata = dev_get_platdata(&i2c->dev);

  	struct tc3589x *tc3589x;

  	enum tc3589x_version version;

  	int ret;

  	if (!pdata) {

  		pdata = tc3589x_of_probe(&i2c->dev, &version);
  		if (IS_ERR(pdata)) {

  			dev_err(&i2c->dev, "No platform data or DT found
  ");

  			return PTR_ERR(pdata);

  		}

  	} else {
  		/* When not probing from device tree we have this ID */
  		version = id->driver_data;

  	}

  	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
  				     | I2C_FUNC_SMBUS_I2C_BLOCK))
  		return -EIO;

  	tc3589x = devm_kzalloc(&i2c->dev, sizeof(struct tc3589x),
  				GFP_KERNEL);

  	if (!tc3589x)

  		return -ENOMEM;

  	mutex_init(&tc3589x->lock);

  	tc3589x->dev = &i2c->dev;
  	tc3589x->i2c = i2c;
  	tc3589x->pdata = pdata;

  	switch (version) {

  	case TC3589X_TC35893:
  	case TC3589X_TC35895:
  	case TC3589X_TC35896:
  		tc3589x->num_gpio = 20;
  		break;
  	case TC3589X_TC35890:
  	case TC3589X_TC35892:
  	case TC3589X_TC35894:
  	case TC3589X_UNKNOWN:
  	default:
  		tc3589x->num_gpio = 24;
  		break;
  	}

  	i2c_set_clientdata(i2c, tc3589x);

  	ret = tc3589x_chip_init(tc3589x);

  	if (ret)

  		return ret;

  	ret = tc3589x_irq_init(tc3589x, np);

  	if (ret)

  		return ret;

  	ret = request_threaded_irq(tc3589x->i2c->irq, NULL, tc3589x_irq,

  				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,

  				   "tc3589x", tc3589x);

  	if (ret) {

  		dev_err(tc3589x->dev, "failed to request IRQ: %d
  ", ret);

  		return ret;

  	}

  	ret = tc3589x_device_init(tc3589x);

  	if (ret) {

  		dev_err(tc3589x->dev, "failed to add child devices
  ");

  		return ret;

  	}
  
  	return 0;

  }

  static int tc3589x_remove(struct i2c_client *client)

  {

  	struct tc3589x *tc3589x = i2c_get_clientdata(client);

  	mfd_remove_devices(tc3589x->dev);

  	return 0;
  }

  #ifdef CONFIG_PM_SLEEP

  static int tc3589x_suspend(struct device *dev)
  {
  	struct tc3589x *tc3589x = dev_get_drvdata(dev);
  	struct i2c_client *client = tc3589x->i2c;
  	int ret = 0;
  
  	/* put the system to sleep mode */
  	if (!device_may_wakeup(&client->dev))
  		ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
  				TC3589x_CLKMODE_MODCTL_SLEEP);
  
  	return ret;
  }
  
  static int tc3589x_resume(struct device *dev)
  {
  	struct tc3589x *tc3589x = dev_get_drvdata(dev);
  	struct i2c_client *client = tc3589x->i2c;
  	int ret = 0;
  
  	/* enable the system into operation */
  	if (!device_may_wakeup(&client->dev))
  		ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
  				TC3589x_CLKMODE_MODCTL_OPERATION);
  
  	return ret;
  }

  #endif

  static SIMPLE_DEV_PM_OPS(tc3589x_dev_pm_ops, tc3589x_suspend, tc3589x_resume);

  static const struct i2c_device_id tc3589x_id[] = {

  	{ "tc35890", TC3589X_TC35890 },
  	{ "tc35892", TC3589X_TC35892 },
  	{ "tc35893", TC3589X_TC35893 },
  	{ "tc35894", TC3589X_TC35894 },
  	{ "tc35895", TC3589X_TC35895 },
  	{ "tc35896", TC3589X_TC35896 },
  	{ "tc3589x", TC3589X_UNKNOWN },

  	{ }
  };

  MODULE_DEVICE_TABLE(i2c, tc3589x_id);

  static struct i2c_driver tc3589x_driver = {

  	.driver = {
  		.name	= "tc3589x",

  		.pm	= &tc3589x_dev_pm_ops,
  		.of_match_table = of_match_ptr(tc3589x_match),
  	},

  	.probe		= tc3589x_probe,

  	.remove		= tc3589x_remove,

  	.id_table	= tc3589x_id,

  };

  static int __init tc3589x_init(void)

  {

  	return i2c_add_driver(&tc3589x_driver);

  }

  subsys_initcall(tc3589x_init);

  static void __exit tc3589x_exit(void)

  {

  	i2c_del_driver(&tc3589x_driver);

  }

  module_exit(tc3589x_exit);

  
  MODULE_LICENSE("GPL v2");

  MODULE_DESCRIPTION("TC3589x MFD core driver");

  MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");