/*
 * extcon-max77843.c - Maxim MAX77843 extcon driver to support
 *			MUIC(Micro USB Interface Controller)
 *
 * Copyright (C) 2015 Samsung Electronics
 * Author: Jaewon Kim <jaewon02.kim@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.
 */

#include <linux/extcon.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mfd/max77843-private.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/workqueue.h>

#define DELAY_MS_DEFAULT		15000	/* unit: millisecond */

enum max77843_muic_status {
	MAX77843_MUIC_STATUS1 = 0,
	MAX77843_MUIC_STATUS2,
	MAX77843_MUIC_STATUS3,

	MAX77843_MUIC_STATUS_NUM,
};

struct max77843_muic_info {
	struct device *dev;
	struct max77843 *max77843;
	struct extcon_dev *edev;

	struct mutex mutex;
	struct work_struct irq_work;
	struct delayed_work wq_detcable;

	u8 status[MAX77843_MUIC_STATUS_NUM];
	int prev_cable_type;
	int prev_chg_type;
	int prev_gnd_type;

	bool irq_adc;
	bool irq_chg;
};

enum max77843_muic_cable_group {
	MAX77843_CABLE_GROUP_ADC = 0,
	MAX77843_CABLE_GROUP_ADC_GND,
	MAX77843_CABLE_GROUP_CHG,
};

enum max77843_muic_adc_debounce_time {
	MAX77843_DEBOUNCE_TIME_5MS = 0,
	MAX77843_DEBOUNCE_TIME_10MS,
	MAX77843_DEBOUNCE_TIME_25MS,
	MAX77843_DEBOUNCE_TIME_38_62MS,
};

/* Define accessory cable type */
enum max77843_muic_accessory_type {
	MAX77843_MUIC_ADC_GROUND = 0,
	MAX77843_MUIC_ADC_SEND_END_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S1_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S2_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S3_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S4_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S5_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S6_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S7_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S8_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S9_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S10_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S11_BUTTON,
	MAX77843_MUIC_ADC_REMOTE_S12_BUTTON,
	MAX77843_MUIC_ADC_RESERVED_ACC_1,
	MAX77843_MUIC_ADC_RESERVED_ACC_2,
	MAX77843_MUIC_ADC_RESERVED_ACC_3,
	MAX77843_MUIC_ADC_RESERVED_ACC_4,
	MAX77843_MUIC_ADC_RESERVED_ACC_5,
	MAX77843_MUIC_ADC_AUDIO_DEVICE_TYPE2,
	MAX77843_MUIC_ADC_PHONE_POWERED_DEV,
	MAX77843_MUIC_ADC_TTY_CONVERTER,
	MAX77843_MUIC_ADC_UART_CABLE,
	MAX77843_MUIC_ADC_CEA936A_TYPE1_CHG,
	MAX77843_MUIC_ADC_FACTORY_MODE_USB_OFF,
	MAX77843_MUIC_ADC_FACTORY_MODE_USB_ON,
	MAX77843_MUIC_ADC_AV_CABLE_NOLOAD,
	MAX77843_MUIC_ADC_CEA936A_TYPE2_CHG,
	MAX77843_MUIC_ADC_FACTORY_MODE_UART_OFF,
	MAX77843_MUIC_ADC_FACTORY_MODE_UART_ON,
	MAX77843_MUIC_ADC_AUDIO_DEVICE_TYPE1,
	MAX77843_MUIC_ADC_OPEN,

	/* The blow accessories should check
	   not only ADC value but also ADC1K and VBVolt value. */
						/* Offset|ADC1K|VBVolt| */
	MAX77843_MUIC_GND_USB_HOST = 0x100,	/*    0x1|    0|     0| */
	MAX77843_MUIC_GND_USB_HOST_VB = 0x101,	/*    0x1|    0|     1| */
	MAX77843_MUIC_GND_MHL = 0x102,		/*    0x1|    1|     0| */
	MAX77843_MUIC_GND_MHL_VB = 0x103,	/*    0x1|    1|     1| */
};

/* Define charger cable type */
enum max77843_muic_charger_type {
	MAX77843_MUIC_CHG_NONE = 0,
	MAX77843_MUIC_CHG_USB,
	MAX77843_MUIC_CHG_DOWNSTREAM,
	MAX77843_MUIC_CHG_DEDICATED,
	MAX77843_MUIC_CHG_SPECIAL_500MA,
	MAX77843_MUIC_CHG_SPECIAL_1A,
	MAX77843_MUIC_CHG_SPECIAL_BIAS,
	MAX77843_MUIC_CHG_RESERVED,
	MAX77843_MUIC_CHG_GND,
};

enum {
	MAX77843_CABLE_USB = 0,
	MAX77843_CABLE_USB_HOST,
	MAX77843_CABLE_TA,
	MAX77843_CABLE_CHARGE_DOWNSTREAM,
	MAX77843_CABLE_FAST_CHARGER,
	MAX77843_CABLE_SLOW_CHARGER,
	MAX77843_CABLE_MHL,
	MAX77843_CABLE_MHL_TA,
	MAX77843_CABLE_JIG_USB_ON,
	MAX77843_CABLE_JIG_USB_OFF,
	MAX77843_CABLE_JIG_UART_ON,
	MAX77843_CABLE_JIG_UART_OFF,

	MAX77843_CABLE_NUM,
};

static const char *max77843_extcon_cable[] = {
	[MAX77843_CABLE_USB]			= "USB",
	[MAX77843_CABLE_USB_HOST]		= "USB-HOST",
	[MAX77843_CABLE_TA]			= "TA",
	[MAX77843_CABLE_CHARGE_DOWNSTREAM]	= "CHARGER-DOWNSTREAM",
	[MAX77843_CABLE_FAST_CHARGER]		= "FAST-CHARGER",
	[MAX77843_CABLE_SLOW_CHARGER]		= "SLOW-CHARGER",
	[MAX77843_CABLE_MHL]			= "MHL",
	[MAX77843_CABLE_MHL_TA]			= "MHL-TA",
	[MAX77843_CABLE_JIG_USB_ON]		= "JIG-USB-ON",
	[MAX77843_CABLE_JIG_USB_OFF]		= "JIG-USB-OFF",
	[MAX77843_CABLE_JIG_UART_ON]		= "JIG-UART-ON",
	[MAX77843_CABLE_JIG_UART_OFF]		= "JIG-UART-OFF",
};

struct max77843_muic_irq {
	unsigned int irq;
	const char *name;
	unsigned int virq;
};

static struct max77843_muic_irq max77843_muic_irqs[] = {
	{ MAX77843_MUIC_IRQ_INT1_ADC,		"MUIC-ADC" },
	{ MAX77843_MUIC_IRQ_INT1_ADCERROR,	"MUIC-ADC_ERROR" },
	{ MAX77843_MUIC_IRQ_INT1_ADC1K,		"MUIC-ADC1K" },
	{ MAX77843_MUIC_IRQ_INT2_CHGTYP,	"MUIC-CHGTYP" },
	{ MAX77843_MUIC_IRQ_INT2_CHGDETRUN,	"MUIC-CHGDETRUN" },
	{ MAX77843_MUIC_IRQ_INT2_DCDTMR,	"MUIC-DCDTMR" },
	{ MAX77843_MUIC_IRQ_INT2_DXOVP,		"MUIC-DXOVP" },
	{ MAX77843_MUIC_IRQ_INT2_VBVOLT,	"MUIC-VBVOLT" },
	{ MAX77843_MUIC_IRQ_INT3_VBADC,		"MUIC-VBADC" },
	{ MAX77843_MUIC_IRQ_INT3_VDNMON,	"MUIC-VDNMON" },
	{ MAX77843_MUIC_IRQ_INT3_DNRES,		"MUIC-DNRES" },
	{ MAX77843_MUIC_IRQ_INT3_MPNACK,	"MUIC-MPNACK"},
	{ MAX77843_MUIC_IRQ_INT3_MRXBUFOW,	"MUIC-MRXBUFOW"},
	{ MAX77843_MUIC_IRQ_INT3_MRXTRF,	"MUIC-MRXTRF"},
	{ MAX77843_MUIC_IRQ_INT3_MRXPERR,	"MUIC-MRXPERR"},
	{ MAX77843_MUIC_IRQ_INT3_MRXRDY,	"MUIC-MRXRDY"},
};

static const struct regmap_config max77843_muic_regmap_config = {
	.reg_bits       = 8,
	.val_bits       = 8,
	.max_register   = MAX77843_MUIC_REG_END,
};

static const struct regmap_irq max77843_muic_irq[] = {
	/* INT1 interrupt */
	{ .reg_offset = 0, .mask = MAX77843_MUIC_ADC, },
	{ .reg_offset = 0, .mask = MAX77843_MUIC_ADCERROR, },
	{ .reg_offset = 0, .mask = MAX77843_MUIC_ADC1K, },

	/* INT2 interrupt */
	{ .reg_offset = 1, .mask = MAX77843_MUIC_CHGTYP, },
	{ .reg_offset = 1, .mask = MAX77843_MUIC_CHGDETRUN, },
	{ .reg_offset = 1, .mask = MAX77843_MUIC_DCDTMR, },
	{ .reg_offset = 1, .mask = MAX77843_MUIC_DXOVP, },
	{ .reg_offset = 1, .mask = MAX77843_MUIC_VBVOLT, },

	/* INT3 interrupt */
	{ .reg_offset = 2, .mask = MAX77843_MUIC_VBADC, },
	{ .reg_offset = 2, .mask = MAX77843_MUIC_VDNMON, },
	{ .reg_offset = 2, .mask = MAX77843_MUIC_DNRES, },
	{ .reg_offset = 2, .mask = MAX77843_MUIC_MPNACK, },
	{ .reg_offset = 2, .mask = MAX77843_MUIC_MRXBUFOW, },
	{ .reg_offset = 2, .mask = MAX77843_MUIC_MRXTRF, },
	{ .reg_offset = 2, .mask = MAX77843_MUIC_MRXPERR, },
	{ .reg_offset = 2, .mask = MAX77843_MUIC_MRXRDY, },
};

static const struct regmap_irq_chip max77843_muic_irq_chip = {
	.name           = "max77843-muic",
	.status_base    = MAX77843_MUIC_REG_INT1,
	.mask_base      = MAX77843_MUIC_REG_INTMASK1,
	.mask_invert    = true,
	.num_regs       = 3,
	.irqs           = max77843_muic_irq,
	.num_irqs       = ARRAY_SIZE(max77843_muic_irq),
};

static int max77843_muic_set_path(struct max77843_muic_info *info,
		u8 val, bool attached)
{
	struct max77843 *max77843 = info->max77843;
	int ret = 0;
	unsigned int ctrl1, ctrl2;

	if (attached)
		ctrl1 = val;
	else
		ctrl1 = CONTROL1_SW_OPEN;

	ret = regmap_update_bits(max77843->regmap_muic,
			MAX77843_MUIC_REG_CONTROL1,
			CONTROL1_COM_SW, ctrl1);
	if (ret < 0) {
		dev_err(info->dev, "Cannot switch MUIC port\n");
		return ret;
	}

	if (attached)
		ctrl2 = MAX77843_MUIC_CONTROL2_CPEN_MASK;
	else
		ctrl2 = MAX77843_MUIC_CONTROL2_LOWPWR_MASK;

	ret = regmap_update_bits(max77843->regmap_muic,
			MAX77843_MUIC_REG_CONTROL2,
			MAX77843_MUIC_CONTROL2_LOWPWR_MASK |
			MAX77843_MUIC_CONTROL2_CPEN_MASK, ctrl2);
	if (ret < 0) {
		dev_err(info->dev, "Cannot update lowpower mode\n");
		return ret;
	}

	dev_dbg(info->dev,
		"CONTROL1 : 0x%02x, CONTROL2 : 0x%02x, state : %s\n",
		ctrl1, ctrl2, attached ? "attached" : "detached");

	return 0;
}

static int max77843_muic_get_cable_type(struct max77843_muic_info *info,
		enum max77843_muic_cable_group group, bool *attached)
{
	int adc, chg_type, cable_type, gnd_type;

	adc = info->status[MAX77843_MUIC_STATUS1] &
			MAX77843_MUIC_STATUS1_ADC_MASK;
	adc >>= STATUS1_ADC_SHIFT;

	switch (group) {
	case MAX77843_CABLE_GROUP_ADC:
		if (adc == MAX77843_MUIC_ADC_OPEN) {
			*attached = false;
			cable_type = info->prev_cable_type;
			info->prev_cable_type = MAX77843_MUIC_ADC_OPEN;
		} else {
			*attached = true;
			cable_type = info->prev_cable_type = adc;
		}
		break;
	case MAX77843_CABLE_GROUP_CHG:
		chg_type = info->status[MAX77843_MUIC_STATUS2] &
				MAX77843_MUIC_STATUS2_CHGTYP_MASK;

		/* Check GROUND accessory with charger cable */
		if (adc == MAX77843_MUIC_ADC_GROUND) {
			if (chg_type == MAX77843_MUIC_CHG_NONE) {
				/* The following state when charger cable is
				 * disconnected but the GROUND accessory still
				 * connected */
				*attached = false;
				cable_type = info->prev_chg_type;
				info->prev_chg_type = MAX77843_MUIC_CHG_NONE;
			} else {

				/* The following state when charger cable is
				 * connected on the GROUND accessory */
				*attached = true;
				cable_type = MAX77843_MUIC_CHG_GND;
				info->prev_chg_type = MAX77843_MUIC_CHG_GND;
			}
			break;
		}

		if (chg_type == MAX77843_MUIC_CHG_NONE) {
			*attached = false;
			cable_type = info->prev_chg_type;
			info->prev_chg_type = MAX77843_MUIC_CHG_NONE;
		} else {
			*attached = true;
			cable_type = info->prev_chg_type = chg_type;
		}
		break;
	case MAX77843_CABLE_GROUP_ADC_GND:
		if (adc == MAX77843_MUIC_ADC_OPEN) {
			*attached = false;
			cable_type = info->prev_gnd_type;
			info->prev_gnd_type = MAX77843_MUIC_ADC_OPEN;
		} else {
			*attached = true;

			/* Offset|ADC1K|VBVolt|
			 *    0x1|    0|     0| USB-HOST
			 *    0x1|    0|     1| USB-HOST with VB
			 *    0x1|    1|     0| MHL
			 *    0x1|    1|     1| MHL with VB */
			/* Get ADC1K register bit */
			gnd_type = (info->status[MAX77843_MUIC_STATUS1] &
					MAX77843_MUIC_STATUS1_ADC1K_MASK);

			/* Get VBVolt register bit */
			gnd_type |= (info->status[MAX77843_MUIC_STATUS2] &
					MAX77843_MUIC_STATUS2_VBVOLT_MASK);
			gnd_type >>= STATUS2_VBVOLT_SHIFT;

			/* Offset of GND cable */
			gnd_type |= MAX77843_MUIC_GND_USB_HOST;
			cable_type = info->prev_gnd_type = gnd_type;
		}
		break;
	default:
		dev_err(info->dev, "Unknown cable group (%d)\n", group);
		cable_type = -EINVAL;
		break;
	}

	return cable_type;
}

static int max77843_muic_adc_gnd_handler(struct max77843_muic_info *info)
{
	int ret, gnd_cable_type;
	bool attached;

	gnd_cable_type = max77843_muic_get_cable_type(info,
			MAX77843_CABLE_GROUP_ADC_GND, &attached);
	dev_dbg(info->dev, "external connector is %s (gnd:0x%02x)\n",
			attached ? "attached" : "detached", gnd_cable_type);

	switch (gnd_cable_type) {
	case MAX77843_MUIC_GND_USB_HOST:
	case MAX77843_MUIC_GND_USB_HOST_VB:
		ret = max77843_muic_set_path(info, CONTROL1_SW_USB, attached);
		if (ret < 0)
			return ret;

		extcon_set_cable_state(info->edev, "USB-HOST", attached);
		break;
	case MAX77843_MUIC_GND_MHL_VB:
	case MAX77843_MUIC_GND_MHL:
		ret = max77843_muic_set_path(info, CONTROL1_SW_OPEN, attached);
		if (ret < 0)
			return ret;

		extcon_set_cable_state(info->edev, "MHL", attached);
		break;
	default:
		dev_err(info->dev, "failed to detect %s accessory(gnd:0x%x)\n",
			attached ? "attached" : "detached", gnd_cable_type);
		return -EINVAL;
	}

	return 0;
}

static int max77843_muic_jig_handler(struct max77843_muic_info *info,
		int cable_type, bool attached)
{
	int ret;

	dev_dbg(info->dev, "external connector is %s (adc:0x%02x)\n",
			attached ? "attached" : "detached", cable_type);

	switch (cable_type) {
	case MAX77843_MUIC_ADC_FACTORY_MODE_USB_OFF:
		ret = max77843_muic_set_path(info, CONTROL1_SW_USB, attached);
		if (ret < 0)
			return ret;
		extcon_set_cable_state(info->edev, "JIG-USB-OFF", attached);
		break;
	case MAX77843_MUIC_ADC_FACTORY_MODE_USB_ON:
		ret = max77843_muic_set_path(info, CONTROL1_SW_USB, attached);
		if (ret < 0)
			return ret;
		extcon_set_cable_state(info->edev, "JIG-USB-ON", attached);
		break;
	case MAX77843_MUIC_ADC_FACTORY_MODE_UART_OFF:
		ret = max77843_muic_set_path(info, CONTROL1_SW_UART, attached);
		if (ret < 0)
			return ret;
		extcon_set_cable_state(info->edev, "JIG-UART-OFF", attached);
		break;
	default:
		ret = max77843_muic_set_path(info, CONTROL1_SW_OPEN, attached);
		if (ret < 0)
			return ret;
		break;
	}

	return 0;
}

static int max77843_muic_adc_handler(struct max77843_muic_info *info)
{
	int ret, cable_type;
	bool attached;

	cable_type = max77843_muic_get_cable_type(info,
			MAX77843_CABLE_GROUP_ADC, &attached);

	dev_dbg(info->dev,
		"external connector is %s (adc:0x%02x, prev_adc:0x%x)\n",
		attached ? "attached" : "detached", cable_type,
		info->prev_cable_type);

	switch (cable_type) {
	case MAX77843_MUIC_ADC_GROUND:
		ret = max77843_muic_adc_gnd_handler(info);
		if (ret < 0)
			return ret;
		break;
	case MAX77843_MUIC_ADC_FACTORY_MODE_USB_OFF:
	case MAX77843_MUIC_ADC_FACTORY_MODE_USB_ON:
	case MAX77843_MUIC_ADC_FACTORY_MODE_UART_OFF:
		ret = max77843_muic_jig_handler(info, cable_type, attached);
		if (ret < 0)
			return ret;
		break;
	case MAX77843_MUIC_ADC_SEND_END_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S1_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S2_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S3_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S4_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S5_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S6_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S7_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S8_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S9_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S10_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S11_BUTTON:
	case MAX77843_MUIC_ADC_REMOTE_S12_BUTTON:
	case MAX77843_MUIC_ADC_RESERVED_ACC_1:
	case MAX77843_MUIC_ADC_RESERVED_ACC_2:
	case MAX77843_MUIC_ADC_RESERVED_ACC_3:
	case MAX77843_MUIC_ADC_RESERVED_ACC_4:
	case MAX77843_MUIC_ADC_RESERVED_ACC_5:
	case MAX77843_MUIC_ADC_AUDIO_DEVICE_TYPE2:
	case MAX77843_MUIC_ADC_PHONE_POWERED_DEV:
	case MAX77843_MUIC_ADC_TTY_CONVERTER:
	case MAX77843_MUIC_ADC_UART_CABLE:
	case MAX77843_MUIC_ADC_CEA936A_TYPE1_CHG:
	case MAX77843_MUIC_ADC_AV_CABLE_NOLOAD:
	case MAX77843_MUIC_ADC_CEA936A_TYPE2_CHG:
	case MAX77843_MUIC_ADC_FACTORY_MODE_UART_ON:
	case MAX77843_MUIC_ADC_AUDIO_DEVICE_TYPE1:
	case MAX77843_MUIC_ADC_OPEN:
		dev_err(info->dev,
			"accessory is %s but it isn't used (adc:0x%x)\n",
			attached ? "attached" : "detached", cable_type);
		return -EAGAIN;
	default:
		dev_err(info->dev,
			"failed to detect %s accessory (adc:0x%x)\n",
			attached ? "attached" : "detached", cable_type);
		return -EINVAL;
	}

	return 0;
}

static int max77843_muic_chg_handler(struct max77843_muic_info *info)
{
	int ret, chg_type, gnd_type;
	bool attached;

	chg_type = max77843_muic_get_cable_type(info,
			MAX77843_CABLE_GROUP_CHG, &attached);

	dev_dbg(info->dev,
		"external connector is %s(chg_type:0x%x, prev_chg_type:0x%x)\n",
		attached ? "attached" : "detached",
		chg_type, info->prev_chg_type);

	switch (chg_type) {
	case MAX77843_MUIC_CHG_USB:
		ret = max77843_muic_set_path(info, CONTROL1_SW_USB, attached);
		if (ret < 0)
			return ret;

		extcon_set_cable_state(info->edev, "USB", attached);
		break;
	case MAX77843_MUIC_CHG_DOWNSTREAM:
		ret = max77843_muic_set_path(info, CONTROL1_SW_OPEN, attached);
		if (ret < 0)
			return ret;

		extcon_set_cable_state(info->edev,
				"CHARGER-DOWNSTREAM", attached);
		break;
	case MAX77843_MUIC_CHG_DEDICATED:
		ret = max77843_muic_set_path(info, CONTROL1_SW_OPEN, attached);
		if (ret < 0)
			return ret;

		extcon_set_cable_state(info->edev, "TA", attached);
		break;
	case MAX77843_MUIC_CHG_SPECIAL_500MA:
		ret = max77843_muic_set_path(info, CONTROL1_SW_OPEN, attached);
		if (ret < 0)
			return ret;

		extcon_set_cable_state(info->edev, "SLOW-CHAREGER", attached);
		break;
	case MAX77843_MUIC_CHG_SPECIAL_1A:
		ret = max77843_muic_set_path(info, CONTROL1_SW_OPEN, attached);
		if (ret < 0)
			return ret;

		extcon_set_cable_state(info->edev, "FAST-CHARGER", attached);
		break;
	case MAX77843_MUIC_CHG_GND:
		gnd_type = max77843_muic_get_cable_type(info,
				MAX77843_CABLE_GROUP_ADC_GND, &attached);

		/* Charger cable on MHL accessory is attach or detach */
		if (gnd_type == MAX77843_MUIC_GND_MHL_VB)
			extcon_set_cable_state(info->edev, "MHL-TA", true);
		else if (gnd_type == MAX77843_MUIC_GND_MHL)
			extcon_set_cable_state(info->edev, "MHL-TA", false);
		break;
	case MAX77843_MUIC_CHG_NONE:
		break;
	default:
		dev_err(info->dev,
			"failed to detect %s accessory (chg_type:0x%x)\n",
			attached ? "attached" : "detached", chg_type);

		max77843_muic_set_path(info, CONTROL1_SW_OPEN, attached);
		return -EINVAL;
	}

	return 0;
}

static void max77843_muic_irq_work(struct work_struct *work)
{
	struct max77843_muic_info *info = container_of(work,
			struct max77843_muic_info, irq_work);
	struct max77843 *max77843 = info->max77843;
	int ret = 0;

	mutex_lock(&info->mutex);

	ret = regmap_bulk_read(max77843->regmap_muic,
			MAX77843_MUIC_REG_STATUS1, info->status,
			MAX77843_MUIC_STATUS_NUM);
	if (ret) {
		dev_err(info->dev, "Cannot read STATUS registers\n");
		mutex_unlock(&info->mutex);
		return;
	}

	if (info->irq_adc) {
		ret = max77843_muic_adc_handler(info);
		if (ret)
			dev_err(info->dev, "Unknown cable type\n");
		info->irq_adc = false;
	}

	if (info->irq_chg) {
		ret = max77843_muic_chg_handler(info);
		if (ret)
			dev_err(info->dev, "Unknown charger type\n");
		info->irq_chg = false;
	}

	mutex_unlock(&info->mutex);
}

static irqreturn_t max77843_muic_irq_handler(int irq, void *data)
{
	struct max77843_muic_info *info = data;
	int i, irq_type = -1;

	for (i = 0; i < ARRAY_SIZE(max77843_muic_irqs); i++)
		if (irq == max77843_muic_irqs[i].virq)
			irq_type = max77843_muic_irqs[i].irq;

	switch (irq_type) {
	case MAX77843_MUIC_IRQ_INT1_ADC:
	case MAX77843_MUIC_IRQ_INT1_ADCERROR:
	case MAX77843_MUIC_IRQ_INT1_ADC1K:
		info->irq_adc = true;
		break;
	case MAX77843_MUIC_IRQ_INT2_CHGTYP:
	case MAX77843_MUIC_IRQ_INT2_CHGDETRUN:
	case MAX77843_MUIC_IRQ_INT2_DCDTMR:
	case MAX77843_MUIC_IRQ_INT2_DXOVP:
	case MAX77843_MUIC_IRQ_INT2_VBVOLT:
		info->irq_chg = true;
		break;
	case MAX77843_MUIC_IRQ_INT3_VBADC:
	case MAX77843_MUIC_IRQ_INT3_VDNMON:
	case MAX77843_MUIC_IRQ_INT3_DNRES:
	case MAX77843_MUIC_IRQ_INT3_MPNACK:
	case MAX77843_MUIC_IRQ_INT3_MRXBUFOW:
	case MAX77843_MUIC_IRQ_INT3_MRXTRF:
	case MAX77843_MUIC_IRQ_INT3_MRXPERR:
	case MAX77843_MUIC_IRQ_INT3_MRXRDY:
		break;
	default:
		dev_err(info->dev, "Cannot recognize IRQ(%d)\n", irq_type);
		break;
	}

	schedule_work(&info->irq_work);

	return IRQ_HANDLED;
}

static void max77843_muic_detect_cable_wq(struct work_struct *work)
{
	struct max77843_muic_info *info = container_of(to_delayed_work(work),
			struct max77843_muic_info, wq_detcable);
	struct max77843 *max77843 = info->max77843;
	int chg_type, adc, ret;
	bool attached;

	mutex_lock(&info->mutex);

	ret = regmap_bulk_read(max77843->regmap_muic,
			MAX77843_MUIC_REG_STATUS1, info->status,
			MAX77843_MUIC_STATUS_NUM);
	if (ret) {
		dev_err(info->dev, "Cannot read STATUS registers\n");
		goto err_cable_wq;
	}

	adc = max77843_muic_get_cable_type(info,
			MAX77843_CABLE_GROUP_ADC, &attached);
	if (attached && adc != MAX77843_MUIC_ADC_OPEN) {
		ret = max77843_muic_adc_handler(info);
		if (ret < 0) {
			dev_err(info->dev, "Cannot detect accessory\n");
			goto err_cable_wq;
		}
	}

	chg_type = max77843_muic_get_cable_type(info,
			MAX77843_CABLE_GROUP_CHG, &attached);
	if (attached && chg_type != MAX77843_MUIC_CHG_NONE) {
		ret = max77843_muic_chg_handler(info);
		if (ret < 0) {
			dev_err(info->dev, "Cannot detect charger accessory\n");
			goto err_cable_wq;
		}
	}

err_cable_wq:
	mutex_unlock(&info->mutex);
}

static int max77843_muic_set_debounce_time(struct max77843_muic_info *info,
		enum max77843_muic_adc_debounce_time time)
{
	struct max77843 *max77843 = info->max77843;
	int ret;

	switch (time) {
	case MAX77843_DEBOUNCE_TIME_5MS:
	case MAX77843_DEBOUNCE_TIME_10MS:
	case MAX77843_DEBOUNCE_TIME_25MS:
	case MAX77843_DEBOUNCE_TIME_38_62MS:
		ret = regmap_update_bits(max77843->regmap_muic,
				MAX77843_MUIC_REG_CONTROL4,
				MAX77843_MUIC_CONTROL4_ADCDBSET_MASK,
				time << CONTROL4_ADCDBSET_SHIFT);
		if (ret < 0) {
			dev_err(info->dev, "Cannot write MUIC regmap\n");
			return ret;
		}
		break;
	default:
		dev_err(info->dev, "Invalid ADC debounce time\n");
		return -EINVAL;
	}

	return 0;
}

static int max77843_init_muic_regmap(struct max77843 *max77843)
{
	int ret;

	max77843->i2c_muic = i2c_new_dummy(max77843->i2c->adapter,
			I2C_ADDR_MUIC);
	if (!max77843->i2c_muic) {
		dev_err(&max77843->i2c->dev,
				"Cannot allocate I2C device for MUIC\n");
		return -ENOMEM;
	}

	i2c_set_clientdata(max77843->i2c_muic, max77843);

	max77843->regmap_muic = devm_regmap_init_i2c(max77843->i2c_muic,
			&max77843_muic_regmap_config);
	if (IS_ERR(max77843->regmap_muic)) {
		ret = PTR_ERR(max77843->regmap_muic);
		goto err_muic_i2c;
	}

	ret = regmap_add_irq_chip(max77843->regmap_muic, max77843->irq,
			IRQF_TRIGGER_LOW | IRQF_ONESHOT | IRQF_SHARED,
			0, &max77843_muic_irq_chip, &max77843->irq_data_muic);
	if (ret < 0) {
		dev_err(&max77843->i2c->dev, "Cannot add MUIC IRQ chip\n");
		goto err_muic_i2c;
	}

	return 0;

err_muic_i2c:
	i2c_unregister_device(max77843->i2c_muic);

	return ret;
}

static int max77843_muic_probe(struct platform_device *pdev)
{
	struct max77843 *max77843 = dev_get_drvdata(pdev->dev.parent);
	struct max77843_muic_info *info;
	unsigned int id;
	int i, ret;

	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	info->dev = &pdev->dev;
	info->max77843 = max77843;

	platform_set_drvdata(pdev, info);
	mutex_init(&info->mutex);

	/* Initialize i2c and regmap */
	ret = max77843_init_muic_regmap(max77843);
	if (ret) {
		dev_err(&pdev->dev, "Failed to init MUIC regmap\n");
		return ret;
	}

	/* Turn off auto detection configuration */
	ret = regmap_update_bits(max77843->regmap_muic,
			MAX77843_MUIC_REG_CONTROL4,
			MAX77843_MUIC_CONTROL4_USBAUTO_MASK |
			MAX77843_MUIC_CONTROL4_FCTAUTO_MASK,
			CONTROL4_AUTO_DISABLE);

	/* Initialize extcon device */
	info->edev = devm_extcon_dev_allocate(&pdev->dev,
			max77843_extcon_cable);
	if (IS_ERR(info->edev)) {
		dev_err(&pdev->dev, "Failed to allocate memory for extcon\n");
		ret = -ENODEV;
		goto err_muic_irq;
	}

	ret = devm_extcon_dev_register(&pdev->dev, info->edev);
	if (ret) {
		dev_err(&pdev->dev, "Failed to register extcon device\n");
		goto err_muic_irq;
	}

	/* Set ADC debounce time */
	max77843_muic_set_debounce_time(info, MAX77843_DEBOUNCE_TIME_25MS);

	/* Set initial path for UART */
	max77843_muic_set_path(info, CONTROL1_SW_UART, true);

	/* Check revision number of MUIC device */
	ret = regmap_read(max77843->regmap_muic, MAX77843_MUIC_REG_ID, &id);
	if (ret < 0) {
		dev_err(&pdev->dev, "Failed to read revision number\n");
		goto err_muic_irq;
	}
	dev_info(info->dev, "MUIC device ID : 0x%x\n", id);

	/* Support virtual irq domain for max77843 MUIC device */
	INIT_WORK(&info->irq_work, max77843_muic_irq_work);

	for (i = 0; i < ARRAY_SIZE(max77843_muic_irqs); i++) {
		struct max77843_muic_irq *muic_irq = &max77843_muic_irqs[i];
		unsigned int virq = 0;

		virq = regmap_irq_get_virq(max77843->irq_data_muic,
				muic_irq->irq);
		if (virq <= 0) {
			ret = -EINVAL;
			goto err_muic_irq;
		}
		muic_irq->virq = virq;

		ret = devm_request_threaded_irq(&pdev->dev, virq, NULL,
				max77843_muic_irq_handler, IRQF_NO_SUSPEND,
				muic_irq->name, info);
		if (ret) {
			dev_err(&pdev->dev,
				"Failed to request irq (IRQ: %d, error: %d)\n",
				muic_irq->irq, ret);
			goto err_muic_irq;
		}
	}

	/* Detect accessory after completing the initialization of platform */
	INIT_DELAYED_WORK(&info->wq_detcable, max77843_muic_detect_cable_wq);
	queue_delayed_work(system_power_efficient_wq,
			&info->wq_detcable, msecs_to_jiffies(DELAY_MS_DEFAULT));

	return 0;

err_muic_irq:
	regmap_del_irq_chip(max77843->irq, max77843->irq_data_muic);
	i2c_unregister_device(max77843->i2c_muic);

	return ret;
}

static int max77843_muic_remove(struct platform_device *pdev)
{
	struct max77843_muic_info *info = platform_get_drvdata(pdev);
	struct max77843 *max77843 = info->max77843;

	cancel_work_sync(&info->irq_work);
	regmap_del_irq_chip(max77843->irq, max77843->irq_data_muic);
	i2c_unregister_device(max77843->i2c_muic);

	return 0;
}

static const struct platform_device_id max77843_muic_id[] = {
	{ "max77843-muic", },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(platform, max77843_muic_id);

static struct platform_driver max77843_muic_driver = {
	.driver		= {
		.name		= "max77843-muic",
	},
	.probe		= max77843_muic_probe,
	.remove		= max77843_muic_remove,
	.id_table	= max77843_muic_id,
};

static int __init max77843_muic_init(void)
{
	return platform_driver_register(&max77843_muic_driver);
}
subsys_initcall(max77843_muic_init);

MODULE_DESCRIPTION("Maxim MAX77843 Extcon driver");
MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
MODULE_LICENSE("GPL");