/*
   * Core driver for TI TPS6586x PMIC family
   *
   * Copyright (c) 2010 CompuLab Ltd.
   * Mike Rapoport <mike@compulab.co.il>
   *
   * Based on da903x.c.
   * Copyright (C) 2008 Compulab, Ltd.
   * Mike Rapoport <mike@compulab.co.il>
   * Copyright (C) 2006-2008 Marvell International Ltd.
   * Eric Miao <eric.miao@marvell.com>
   *
   * 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/interrupt.h>
  #include <linux/irq.h>
  #include <linux/irqdomain.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/mutex.h>
  #include <linux/slab.h>
  #include <linux/err.h>
  #include <linux/i2c.h>
  #include <linux/platform_device.h>
  #include <linux/regmap.h>
  #include <linux/of.h>
  
  #include <linux/mfd/core.h>
  #include <linux/mfd/tps6586x.h>
  
  #define TPS6586X_SUPPLYENE	0x14
  #define EXITSLREQ_BIT		BIT(1)
  #define SLEEP_MODE_BIT		BIT(3)
  
  /* interrupt control registers */
  #define TPS6586X_INT_ACK1	0xb5
  #define TPS6586X_INT_ACK2	0xb6
  #define TPS6586X_INT_ACK3	0xb7
  #define TPS6586X_INT_ACK4	0xb8
  
  /* interrupt mask registers */
  #define TPS6586X_INT_MASK1	0xb0
  #define TPS6586X_INT_MASK2	0xb1
  #define TPS6586X_INT_MASK3	0xb2
  #define TPS6586X_INT_MASK4	0xb3
  #define TPS6586X_INT_MASK5	0xb4
  
  /* device id */
  #define TPS6586X_VERSIONCRC	0xcd
  
  /* Maximum register */
  #define TPS6586X_MAX_REGISTER	(TPS6586X_VERSIONCRC + 1)
  
  struct tps6586x_irq_data {
  	u8	mask_reg;
  	u8	mask_mask;
  };
  
  #define TPS6586X_IRQ(_reg, _mask)				\
  	{							\
  		.mask_reg = (_reg) - TPS6586X_INT_MASK1,	\
  		.mask_mask = (_mask),				\
  	}
  
  static const struct tps6586x_irq_data tps6586x_irqs[] = {
  	[TPS6586X_INT_PLDO_0]	= TPS6586X_IRQ(TPS6586X_INT_MASK1, 1 << 0),
  	[TPS6586X_INT_PLDO_1]	= TPS6586X_IRQ(TPS6586X_INT_MASK1, 1 << 1),
  	[TPS6586X_INT_PLDO_2]	= TPS6586X_IRQ(TPS6586X_INT_MASK1, 1 << 2),
  	[TPS6586X_INT_PLDO_3]	= TPS6586X_IRQ(TPS6586X_INT_MASK1, 1 << 3),
  	[TPS6586X_INT_PLDO_4]	= TPS6586X_IRQ(TPS6586X_INT_MASK1, 1 << 4),
  	[TPS6586X_INT_PLDO_5]	= TPS6586X_IRQ(TPS6586X_INT_MASK1, 1 << 5),
  	[TPS6586X_INT_PLDO_6]	= TPS6586X_IRQ(TPS6586X_INT_MASK1, 1 << 6),
  	[TPS6586X_INT_PLDO_7]	= TPS6586X_IRQ(TPS6586X_INT_MASK1, 1 << 7),
  	[TPS6586X_INT_COMP_DET]	= TPS6586X_IRQ(TPS6586X_INT_MASK4, 1 << 0),
  	[TPS6586X_INT_ADC]	= TPS6586X_IRQ(TPS6586X_INT_MASK2, 1 << 1),
  	[TPS6586X_INT_PLDO_8]	= TPS6586X_IRQ(TPS6586X_INT_MASK2, 1 << 2),
  	[TPS6586X_INT_PLDO_9]	= TPS6586X_IRQ(TPS6586X_INT_MASK2, 1 << 3),
  	[TPS6586X_INT_PSM_0]	= TPS6586X_IRQ(TPS6586X_INT_MASK2, 1 << 4),
  	[TPS6586X_INT_PSM_1]	= TPS6586X_IRQ(TPS6586X_INT_MASK2, 1 << 5),
  	[TPS6586X_INT_PSM_2]	= TPS6586X_IRQ(TPS6586X_INT_MASK2, 1 << 6),
  	[TPS6586X_INT_PSM_3]	= TPS6586X_IRQ(TPS6586X_INT_MASK2, 1 << 7),
  	[TPS6586X_INT_RTC_ALM1]	= TPS6586X_IRQ(TPS6586X_INT_MASK5, 1 << 4),
  	[TPS6586X_INT_ACUSB_OVP] = TPS6586X_IRQ(TPS6586X_INT_MASK5, 0x03),
  	[TPS6586X_INT_USB_DET]	= TPS6586X_IRQ(TPS6586X_INT_MASK5, 1 << 2),
  	[TPS6586X_INT_AC_DET]	= TPS6586X_IRQ(TPS6586X_INT_MASK5, 1 << 3),
  	[TPS6586X_INT_BAT_DET]	= TPS6586X_IRQ(TPS6586X_INT_MASK3, 1 << 0),
  	[TPS6586X_INT_CHG_STAT]	= TPS6586X_IRQ(TPS6586X_INT_MASK4, 0xfc),
  	[TPS6586X_INT_CHG_TEMP]	= TPS6586X_IRQ(TPS6586X_INT_MASK3, 0x06),
  	[TPS6586X_INT_PP]	= TPS6586X_IRQ(TPS6586X_INT_MASK3, 0xf0),
  	[TPS6586X_INT_RESUME]	= TPS6586X_IRQ(TPS6586X_INT_MASK5, 1 << 5),
  	[TPS6586X_INT_LOW_SYS]	= TPS6586X_IRQ(TPS6586X_INT_MASK5, 1 << 6),
  	[TPS6586X_INT_RTC_ALM2] = TPS6586X_IRQ(TPS6586X_INT_MASK4, 1 << 1),
  };
  
  static struct resource tps6586x_rtc_resources[] = {
  	{
  		.start  = TPS6586X_INT_RTC_ALM1,
  		.end	= TPS6586X_INT_RTC_ALM1,
  		.flags	= IORESOURCE_IRQ,
  	},
  };
  
  static const struct mfd_cell tps6586x_cell[] = {
  	{
  		.name = "tps6586x-gpio",
  	},
  	{
  		.name = "tps6586x-regulator",
  	},
  	{
  		.name = "tps6586x-rtc",
  		.num_resources = ARRAY_SIZE(tps6586x_rtc_resources),
  		.resources = &tps6586x_rtc_resources[0],
  	},
  	{
  		.name = "tps6586x-onkey",
  	},
  };
  
  struct tps6586x {
  	struct device		*dev;
  	struct i2c_client	*client;
  	struct regmap		*regmap;
  	int			version;
  
  	int			irq;
  	struct irq_chip		irq_chip;
  	struct mutex		irq_lock;
  	int			irq_base;
  	u32			irq_en;
  	u8			mask_reg[5];
  	struct irq_domain	*irq_domain;
  };
  
  static inline struct tps6586x *dev_to_tps6586x(struct device *dev)
  {
  	return i2c_get_clientdata(to_i2c_client(dev));
  }
  
  int tps6586x_write(struct device *dev, int reg, uint8_t val)
  {
  	struct tps6586x *tps6586x = dev_to_tps6586x(dev);
  
  	return regmap_write(tps6586x->regmap, reg, val);
  }
  EXPORT_SYMBOL_GPL(tps6586x_write);
  
  int tps6586x_writes(struct device *dev, int reg, int len, uint8_t *val)
  {
  	struct tps6586x *tps6586x = dev_to_tps6586x(dev);
  
  	return regmap_bulk_write(tps6586x->regmap, reg, val, len);
  }
  EXPORT_SYMBOL_GPL(tps6586x_writes);
  
  int tps6586x_read(struct device *dev, int reg, uint8_t *val)
  {
  	struct tps6586x *tps6586x = dev_to_tps6586x(dev);
  	unsigned int rval;
  	int ret;
  
  	ret = regmap_read(tps6586x->regmap, reg, &rval);
  	if (!ret)
  		*val = rval;
  	return ret;
  }
  EXPORT_SYMBOL_GPL(tps6586x_read);
  
  int tps6586x_reads(struct device *dev, int reg, int len, uint8_t *val)
  {
  	struct tps6586x *tps6586x = dev_to_tps6586x(dev);
  
  	return regmap_bulk_read(tps6586x->regmap, reg, val, len);
  }
  EXPORT_SYMBOL_GPL(tps6586x_reads);
  
  int tps6586x_set_bits(struct device *dev, int reg, uint8_t bit_mask)
  {
  	struct tps6586x *tps6586x = dev_to_tps6586x(dev);
  
  	return regmap_update_bits(tps6586x->regmap, reg, bit_mask, bit_mask);
  }
  EXPORT_SYMBOL_GPL(tps6586x_set_bits);
  
  int tps6586x_clr_bits(struct device *dev, int reg, uint8_t bit_mask)
  {
  	struct tps6586x *tps6586x = dev_to_tps6586x(dev);
  
  	return regmap_update_bits(tps6586x->regmap, reg, bit_mask, 0);
  }
  EXPORT_SYMBOL_GPL(tps6586x_clr_bits);
  
  int tps6586x_update(struct device *dev, int reg, uint8_t val, uint8_t mask)
  {
  	struct tps6586x *tps6586x = dev_to_tps6586x(dev);
  
  	return regmap_update_bits(tps6586x->regmap, reg, mask, val);
  }
  EXPORT_SYMBOL_GPL(tps6586x_update);
  
  int tps6586x_irq_get_virq(struct device *dev, int irq)
  {
  	struct tps6586x *tps6586x = dev_to_tps6586x(dev);
  
  	return irq_create_mapping(tps6586x->irq_domain, irq);
  }
  EXPORT_SYMBOL_GPL(tps6586x_irq_get_virq);
  
  int tps6586x_get_version(struct device *dev)
  {
  	struct tps6586x *tps6586x = dev_get_drvdata(dev);
  
  	return tps6586x->version;
  }
  EXPORT_SYMBOL_GPL(tps6586x_get_version);
  
  static int __remove_subdev(struct device *dev, void *unused)
  {
  	platform_device_unregister(to_platform_device(dev));
  	return 0;
  }
  
  static int tps6586x_remove_subdevs(struct tps6586x *tps6586x)
  {
  	return device_for_each_child(tps6586x->dev, NULL, __remove_subdev);
  }
  
  static void tps6586x_irq_lock(struct irq_data *data)
  {
  	struct tps6586x *tps6586x = irq_data_get_irq_chip_data(data);
  
  	mutex_lock(&tps6586x->irq_lock);
  }
  
  static void tps6586x_irq_enable(struct irq_data *irq_data)
  {
  	struct tps6586x *tps6586x = irq_data_get_irq_chip_data(irq_data);
  	unsigned int __irq = irq_data->hwirq;
  	const struct tps6586x_irq_data *data = &tps6586x_irqs[__irq];
  
  	tps6586x->mask_reg[data->mask_reg] &= ~data->mask_mask;
  	tps6586x->irq_en |= (1 << __irq);
  }
  
  static void tps6586x_irq_disable(struct irq_data *irq_data)
  {
  	struct tps6586x *tps6586x = irq_data_get_irq_chip_data(irq_data);
  
  	unsigned int __irq = irq_data->hwirq;
  	const struct tps6586x_irq_data *data = &tps6586x_irqs[__irq];
  
  	tps6586x->mask_reg[data->mask_reg] |= data->mask_mask;
  	tps6586x->irq_en &= ~(1 << __irq);
  }
  
  static void tps6586x_irq_sync_unlock(struct irq_data *data)
  {
  	struct tps6586x *tps6586x = irq_data_get_irq_chip_data(data);
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(tps6586x->mask_reg); i++) {
  		int ret;
  		ret = tps6586x_write(tps6586x->dev,
  					    TPS6586X_INT_MASK1 + i,
  					    tps6586x->mask_reg[i]);
  		WARN_ON(ret);
  	}
  
  	mutex_unlock(&tps6586x->irq_lock);
  }
  
  #ifdef CONFIG_PM_SLEEP
  static int tps6586x_irq_set_wake(struct irq_data *irq_data, unsigned int on)
  {
  	struct tps6586x *tps6586x = irq_data_get_irq_chip_data(irq_data);
  	return irq_set_irq_wake(tps6586x->irq, on);
  }
  #else
  #define tps6586x_irq_set_wake NULL
  #endif
  
  static struct irq_chip tps6586x_irq_chip = {
  	.name = "tps6586x",
  	.irq_bus_lock = tps6586x_irq_lock,
  	.irq_bus_sync_unlock = tps6586x_irq_sync_unlock,
  	.irq_disable = tps6586x_irq_disable,
  	.irq_enable = tps6586x_irq_enable,
  	.irq_set_wake = tps6586x_irq_set_wake,
  };
  
  static int tps6586x_irq_map(struct irq_domain *h, unsigned int virq,
  				irq_hw_number_t hw)
  {
  	struct tps6586x *tps6586x = h->host_data;
  
  	irq_set_chip_data(virq, tps6586x);
  	irq_set_chip_and_handler(virq, &tps6586x_irq_chip, handle_simple_irq);
  	irq_set_nested_thread(virq, 1);
  
  	/* ARM needs us to explicitly flag the IRQ as valid
  	 * and will set them noprobe when we do so. */
  #ifdef CONFIG_ARM
  	set_irq_flags(virq, IRQF_VALID);
  #else
  	irq_set_noprobe(virq);
  #endif
  
  	return 0;
  }
  
  static struct irq_domain_ops tps6586x_domain_ops = {
  	.map    = tps6586x_irq_map,
  	.xlate  = irq_domain_xlate_twocell,
  };
  
  static irqreturn_t tps6586x_irq(int irq, void *data)
  {
  	struct tps6586x *tps6586x = data;
  	u32 acks;
  	int ret = 0;
  
  	ret = tps6586x_reads(tps6586x->dev, TPS6586X_INT_ACK1,
  			     sizeof(acks), (uint8_t *)&acks);
  
  	if (ret < 0) {
  		dev_err(tps6586x->dev, "failed to read interrupt status
  ");
  		return IRQ_NONE;
  	}
  
  	acks = le32_to_cpu(acks);
  
  	while (acks) {
  		int i = __ffs(acks);
  
  		if (tps6586x->irq_en & (1 << i))
  			handle_nested_irq(
  				irq_find_mapping(tps6586x->irq_domain, i));
  
  		acks &= ~(1 << i);
  	}
  
  	return IRQ_HANDLED;
  }
  
  static int tps6586x_irq_init(struct tps6586x *tps6586x, int irq,
  				       int irq_base)
  {
  	int i, ret;
  	u8 tmp[4];
  	int new_irq_base;
  	int irq_num = ARRAY_SIZE(tps6586x_irqs);
  
  	tps6586x->irq = irq;
  
  	mutex_init(&tps6586x->irq_lock);
  	for (i = 0; i < 5; i++) {
  		tps6586x->mask_reg[i] = 0xff;
  		tps6586x_write(tps6586x->dev, TPS6586X_INT_MASK1 + i, 0xff);
  	}
  
  	tps6586x_reads(tps6586x->dev, TPS6586X_INT_ACK1, sizeof(tmp), tmp);
  
  	if  (irq_base > 0) {
  		new_irq_base = irq_alloc_descs(irq_base, 0, irq_num, -1);
  		if (new_irq_base < 0) {
  			dev_err(tps6586x->dev,
  				"Failed to alloc IRQs: %d
  ", new_irq_base);
  			return new_irq_base;
  		}
  	} else {
  		new_irq_base = 0;
  	}
  
  	tps6586x->irq_domain = irq_domain_add_simple(tps6586x->dev->of_node,
  				irq_num, new_irq_base, &tps6586x_domain_ops,
  				tps6586x);
  	if (!tps6586x->irq_domain) {
  		dev_err(tps6586x->dev, "Failed to create IRQ domain
  ");
  		return -ENOMEM;
  	}
  	ret = request_threaded_irq(irq, NULL, tps6586x_irq, IRQF_ONESHOT,
  				   "tps6586x", tps6586x);
  
  	if (!ret)
  		device_init_wakeup(tps6586x->dev, 1);
  
  	return ret;
  }
  
  static int tps6586x_add_subdevs(struct tps6586x *tps6586x,
  					  struct tps6586x_platform_data *pdata)
  {
  	struct tps6586x_subdev_info *subdev;
  	struct platform_device *pdev;
  	int i, ret = 0;
  
  	for (i = 0; i < pdata->num_subdevs; i++) {
  		subdev = &pdata->subdevs[i];
  
  		pdev = platform_device_alloc(subdev->name, subdev->id);
  		if (!pdev) {
  			ret = -ENOMEM;
  			goto failed;
  		}
  
  		pdev->dev.parent = tps6586x->dev;
  		pdev->dev.platform_data = subdev->platform_data;
  		pdev->dev.of_node = subdev->of_node;
  
  		ret = platform_device_add(pdev);
  		if (ret) {
  			platform_device_put(pdev);
  			goto failed;
  		}
  	}
  	return 0;
  
  failed:
  	tps6586x_remove_subdevs(tps6586x);
  	return ret;
  }
  
  #ifdef CONFIG_OF
  static struct tps6586x_platform_data *tps6586x_parse_dt(struct i2c_client *client)
  {
  	struct device_node *np = client->dev.of_node;
  	struct tps6586x_platform_data *pdata;
  
  	pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
  	if (!pdata) {
  		dev_err(&client->dev, "Memory allocation failed
  ");
  		return NULL;
  	}
  
  	pdata->num_subdevs = 0;
  	pdata->subdevs = NULL;
  	pdata->gpio_base = -1;
  	pdata->irq_base = -1;
  	pdata->pm_off = of_property_read_bool(np, "ti,system-power-controller");
  
  	return pdata;
  }
  
  static struct of_device_id tps6586x_of_match[] = {
  	{ .compatible = "ti,tps6586x", },
  	{ },
  };
  #else
  static struct tps6586x_platform_data *tps6586x_parse_dt(struct i2c_client *client)
  {
  	return NULL;
  }
  #endif
  
  static bool is_volatile_reg(struct device *dev, unsigned int reg)
  {
  	/* Cache all interrupt mask register */
  	if ((reg >= TPS6586X_INT_MASK1) && (reg <= TPS6586X_INT_MASK5))
  		return false;
  
  	return true;
  }
  
  static const struct regmap_config tps6586x_regmap_config = {
  	.reg_bits = 8,
  	.val_bits = 8,
  	.max_register = TPS6586X_MAX_REGISTER - 1,
  	.volatile_reg = is_volatile_reg,
  	.cache_type = REGCACHE_RBTREE,
  };
  
  static struct device *tps6586x_dev;
  static void tps6586x_power_off(void)
  {
  	if (tps6586x_clr_bits(tps6586x_dev, TPS6586X_SUPPLYENE, EXITSLREQ_BIT))
  		return;
  
  	tps6586x_set_bits(tps6586x_dev, TPS6586X_SUPPLYENE, SLEEP_MODE_BIT);
  }
  
  static void tps6586x_print_version(struct i2c_client *client, int version)
  {
  	const char *name;
  
  	switch (version) {
  	case TPS658621A:
  		name = "TPS658621A";
  		break;
  	case TPS658621CD:
  		name = "TPS658621C/D";
  		break;
  	case TPS658623:
  		name = "TPS658623";
  		break;
  	case TPS658643:
  		name = "TPS658643";
  		break;
  	default:
  		name = "TPS6586X";
  		break;
  	}
  
  	dev_info(&client->dev, "Found %s, VERSIONCRC is %02x
  ", name, version);
  }
  
  static int tps6586x_i2c_probe(struct i2c_client *client,
  					const struct i2c_device_id *id)
  {
  	struct tps6586x_platform_data *pdata = dev_get_platdata(&client->dev);
  	struct tps6586x *tps6586x;
  	int ret;
  	int version;
  
  	if (!pdata && client->dev.of_node)
  		pdata = tps6586x_parse_dt(client);
  
  	if (!pdata) {
  		dev_err(&client->dev, "tps6586x requires platform data
  ");
  		return -ENOTSUPP;
  	}
  
  	version = i2c_smbus_read_byte_data(client, TPS6586X_VERSIONCRC);
  	if (version < 0) {
  		dev_err(&client->dev, "Chip ID read failed: %d
  ", version);
  		return -EIO;
  	}
  
  	tps6586x = devm_kzalloc(&client->dev, sizeof(*tps6586x), GFP_KERNEL);
  	if (!tps6586x)
  		return -ENOMEM;
  
  	tps6586x->version = version;
  	tps6586x_print_version(client, tps6586x->version);
  
  	tps6586x->client = client;
  	tps6586x->dev = &client->dev;
  	i2c_set_clientdata(client, tps6586x);
  
  	tps6586x->regmap = devm_regmap_init_i2c(client,
  					&tps6586x_regmap_config);
  	if (IS_ERR(tps6586x->regmap)) {
  		ret = PTR_ERR(tps6586x->regmap);
  		dev_err(&client->dev, "regmap init failed: %d
  ", ret);
  		return ret;
  	}
  
  
  	if (client->irq) {
  		ret = tps6586x_irq_init(tps6586x, client->irq,
  					pdata->irq_base);
  		if (ret) {
  			dev_err(&client->dev, "IRQ init failed: %d
  ", ret);
  			return ret;
  		}
  	}
  
  	ret = mfd_add_devices(tps6586x->dev, -1,
  			      tps6586x_cell, ARRAY_SIZE(tps6586x_cell),
  			      NULL, 0, tps6586x->irq_domain);
  	if (ret < 0) {
  		dev_err(&client->dev, "mfd_add_devices failed: %d
  ", ret);
  		goto err_mfd_add;
  	}
  
  	ret = tps6586x_add_subdevs(tps6586x, pdata);
  	if (ret) {
  		dev_err(&client->dev, "add devices failed: %d
  ", ret);
  		goto err_add_devs;
  	}
  
  	if (pdata->pm_off && !pm_power_off) {
  		tps6586x_dev = &client->dev;
  		pm_power_off = tps6586x_power_off;
  	}
  
  	return 0;
  
  err_add_devs:
  	mfd_remove_devices(tps6586x->dev);
  err_mfd_add:
  	if (client->irq)
  		free_irq(client->irq, tps6586x);
  	return ret;
  }
  
  static int tps6586x_i2c_remove(struct i2c_client *client)
  {
  	struct tps6586x *tps6586x = i2c_get_clientdata(client);
  
  	tps6586x_remove_subdevs(tps6586x);
  	mfd_remove_devices(tps6586x->dev);
  	if (client->irq)
  		free_irq(client->irq, tps6586x);
  	return 0;
  }
  
  static const struct i2c_device_id tps6586x_id_table[] = {
  	{ "tps6586x", 0 },
  	{ },
  };
  MODULE_DEVICE_TABLE(i2c, tps6586x_id_table);
  
  static struct i2c_driver tps6586x_driver = {
  	.driver	= {
  		.name	= "tps6586x",
  		.owner	= THIS_MODULE,
  		.of_match_table = of_match_ptr(tps6586x_of_match),
  	},
  	.probe		= tps6586x_i2c_probe,
  	.remove		= tps6586x_i2c_remove,
  	.id_table	= tps6586x_id_table,
  };
  
  static int __init tps6586x_init(void)
  {
  	return i2c_add_driver(&tps6586x_driver);
  }
  subsys_initcall(tps6586x_init);
  
  static void __exit tps6586x_exit(void)
  {
  	i2c_del_driver(&tps6586x_driver);
  }
  module_exit(tps6586x_exit);
  
  MODULE_DESCRIPTION("TPS6586X core driver");
  MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
  MODULE_LICENSE("GPL");