extcon: MAX77693: Add extcon-max77693 driver to support Maxim MAX77693 MUIC device

This patch support Maxim MAX77693 MUIC device by using EXTCON Subsystem
to handle various external connector. The extcon-max77693 use regmap
method for i2c communication and support irq domain instead of previous
method of irq base.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 790 insertions, 0 deletions

diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
index bb385ac629a..16716356d1f 100644
--- a/drivers/extcon/Kconfig
+++ b/drivers/extcon/Kconfig
@@ -21,6 +21,16 @@ config EXTCON_GPIO
 	  Say Y here to enable GPIO based extcon support. Note that GPIO
 	  extcon supports single state per extcon instance.
 
+config EXTCON_MAX77693
+	tristate "MAX77693 EXTCON Support"
+	depends on MFD_MAX77693
+	select IRQ_DOMAIN
+	select REGMAP_I2C
+	help
+	  If you say yes here you get support for the MUIC device of
+	  Maxim MAX77693 PMIC. The MAX77693 MUIC is a USB port accessory
+	  detector and switch.
+
 config EXTCON_MAX8997
 	tristate "MAX8997 EXTCON Support"
 	depends on MFD_MAX8997
diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
index e932caaa311..88961b33234 100644
--- a/drivers/extcon/Makefile
+++ b/drivers/extcon/Makefile
@@ -4,5 +4,6 @@
 
 obj-$(CONFIG_EXTCON)		+= extcon_class.o
 obj-$(CONFIG_EXTCON_GPIO)	+= extcon_gpio.o
+obj-$(CONFIG_EXTCON_MAX77693)	+= extcon-max77693.o
 obj-$(CONFIG_EXTCON_MAX8997)	+= extcon-max8997.o
 obj-$(CONFIG_EXTCON_ARIZONA)	+= extcon-arizona.o
diff --git a/drivers/extcon/extcon-max77693.c b/drivers/extcon/extcon-max77693.c
new file mode 100644
index 00000000000..920a609b2c3
--- /dev/null
+++ b/drivers/extcon/extcon-max77693.c
@@ -0,0 +1,779 @@
+/*
+ * extcon-max77693.c - MAX77693 extcon driver to support MAX77693 MUIC
+ *
+ * Copyright (C) 2012 Samsung Electrnoics
+ * Chanwoo Choi <cw00.choi@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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/max77693.h>
+#include <linux/mfd/max77693-private.h>
+#include <linux/extcon.h>
+#include <linux/regmap.h>
+#include <linux/irqdomain.h>
+
+#define	DEV_NAME			"max77693-muic"
+
+/* MAX77693 MUIC - STATUS1~3 Register */
+#define STATUS1_ADC_SHIFT		(0)
+#define STATUS1_ADCLOW_SHIFT		(5)
+#define STATUS1_ADCERR_SHIFT		(6)
+#define STATUS1_ADC1K_SHIFT		(7)
+#define STATUS1_ADC_MASK		(0x1f << STATUS1_ADC_SHIFT)
+#define STATUS1_ADCLOW_MASK		(0x1 << STATUS1_ADCLOW_SHIFT)
+#define STATUS1_ADCERR_MASK		(0x1 << STATUS1_ADCERR_SHIFT)
+#define STATUS1_ADC1K_MASK		(0x1 << STATUS1_ADC1K_SHIFT)
+
+#define STATUS2_CHGTYP_SHIFT		(0)
+#define STATUS2_CHGDETRUN_SHIFT		(3)
+#define STATUS2_DCDTMR_SHIFT		(4)
+#define STATUS2_DXOVP_SHIFT		(5)
+#define STATUS2_VBVOLT_SHIFT		(6)
+#define STATUS2_VIDRM_SHIFT		(7)
+#define STATUS2_CHGTYP_MASK		(0x7 << STATUS2_CHGTYP_SHIFT)
+#define STATUS2_CHGDETRUN_MASK		(0x1 << STATUS2_CHGDETRUN_SHIFT)
+#define STATUS2_DCDTMR_MASK		(0x1 << STATUS2_DCDTMR_SHIFT)
+#define STATUS2_DXOVP_MASK		(0x1 << STATUS2_DXOVP_SHIFT)
+#define STATUS2_VBVOLT_MASK		(0x1 << STATUS2_VBVOLT_SHIFT)
+#define STATUS2_VIDRM_MASK		(0x1 << STATUS2_VIDRM_SHIFT)
+
+#define STATUS3_OVP_SHIFT		(2)
+#define STATUS3_OVP_MASK		(0x1 << STATUS3_OVP_SHIFT)
+
+/* MAX77693 CDETCTRL1~2 register */
+#define CDETCTRL1_CHGDETEN_SHIFT	(0)
+#define CDETCTRL1_CHGTYPMAN_SHIFT	(1)
+#define CDETCTRL1_DCDEN_SHIFT		(2)
+#define CDETCTRL1_DCD2SCT_SHIFT		(3)
+#define CDETCTRL1_CDDELAY_SHIFT		(4)
+#define CDETCTRL1_DCDCPL_SHIFT		(5)
+#define CDETCTRL1_CDPDET_SHIFT		(7)
+#define CDETCTRL1_CHGDETEN_MASK		(0x1 << CDETCTRL1_CHGDETEN_SHIFT)
+#define CDETCTRL1_CHGTYPMAN_MASK	(0x1 << CDETCTRL1_CHGTYPMAN_SHIFT)
+#define CDETCTRL1_DCDEN_MASK		(0x1 << CDETCTRL1_DCDEN_SHIFT)
+#define CDETCTRL1_DCD2SCT_MASK		(0x1 << CDETCTRL1_DCD2SCT_SHIFT)
+#define CDETCTRL1_CDDELAY_MASK		(0x1 << CDETCTRL1_CDDELAY_SHIFT)
+#define CDETCTRL1_DCDCPL_MASK		(0x1 << CDETCTRL1_DCDCPL_SHIFT)
+#define CDETCTRL1_CDPDET_MASK		(0x1 << CDETCTRL1_CDPDET_SHIFT)
+
+#define CDETCTRL2_VIDRMEN_SHIFT		(1)
+#define CDETCTRL2_DXOVPEN_SHIFT		(3)
+#define CDETCTRL2_VIDRMEN_MASK		(0x1 << CDETCTRL2_VIDRMEN_SHIFT)
+#define CDETCTRL2_DXOVPEN_MASK		(0x1 << CDETCTRL2_DXOVPEN_SHIFT)
+
+/* MAX77693 MUIC - CONTROL1~3 register */
+#define COMN1SW_SHIFT			(0)
+#define COMP2SW_SHIFT			(3)
+#define COMN1SW_MASK			(0x7 << COMN1SW_SHIFT)
+#define COMP2SW_MASK			(0x7 << COMP2SW_SHIFT)
+#define COMP_SW_MASK			(COMP2SW_MASK | COMN1SW_MASK)
+#define CONTROL1_SW_USB			((1 << COMP2SW_SHIFT) \
+						| (1 << COMN1SW_SHIFT))
+#define CONTROL1_SW_AUDIO		((2 << COMP2SW_SHIFT) \
+						| (2 << COMN1SW_SHIFT))
+#define CONTROL1_SW_UART		((3 << COMP2SW_SHIFT) \
+						| (3 << COMN1SW_SHIFT))
+#define CONTROL1_SW_OPEN		((0 << COMP2SW_SHIFT) \
+						| (0 << COMN1SW_SHIFT))
+
+#define CONTROL2_LOWPWR_SHIFT		(0)
+#define CONTROL2_ADCEN_SHIFT		(1)
+#define CONTROL2_CPEN_SHIFT		(2)
+#define CONTROL2_SFOUTASRT_SHIFT	(3)
+#define CONTROL2_SFOUTORD_SHIFT		(4)
+#define CONTROL2_ACCDET_SHIFT		(5)
+#define CONTROL2_USBCPINT_SHIFT		(6)
+#define CONTROL2_RCPS_SHIFT		(7)
+#define CONTROL2_LOWPWR_MASK		(0x1 << CONTROL2_LOWPWR_SHIFT)
+#define CONTROL2_ADCEN_MASK		(0x1 << CONTROL2_ADCEN_SHIFT)
+#define CONTROL2_CPEN_MASK		(0x1 << CONTROL2_CPEN_SHIFT)
+#define CONTROL2_SFOUTASRT_MASK		(0x1 << CONTROL2_SFOUTASRT_SHIFT)
+#define CONTROL2_SFOUTORD_MASK		(0x1 << CONTROL2_SFOUTORD_SHIFT)
+#define CONTROL2_ACCDET_MASK		(0x1 << CONTROL2_ACCDET_SHIFT)
+#define CONTROL2_USBCPINT_MASK		(0x1 << CONTROL2_USBCPINT_SHIFT)
+#define CONTROL2_RCPS_MASK		(0x1 << CONTROL2_RCPS_SHIFT)
+
+#define CONTROL3_JIGSET_SHIFT		(0)
+#define CONTROL3_BTLDSET_SHIFT		(2)
+#define CONTROL3_ADCDBSET_SHIFT		(4)
+#define CONTROL3_JIGSET_MASK		(0x3 << CONTROL3_JIGSET_SHIFT)
+#define CONTROL3_BTLDSET_MASK		(0x3 << CONTROL3_BTLDSET_SHIFT)
+#define CONTROL3_ADCDBSET_MASK		(0x3 << CONTROL3_ADCDBSET_SHIFT)
+
+enum max77693_muic_adc_debounce_time {
+	ADC_DEBOUNCE_TIME_5MS = 0,
+	ADC_DEBOUNCE_TIME_10MS,
+	ADC_DEBOUNCE_TIME_25MS,
+	ADC_DEBOUNCE_TIME_38_62MS,
+};
+
+struct max77693_muic_info {
+	struct device *dev;
+	struct max77693_dev *max77693;
+	struct extcon_dev *edev;
+	int prev_adc;
+	int prev_adc_gnd;
+	int prev_chg_type;
+	u8 status[2];
+
+	int irq;
+	struct work_struct irq_work;
+	struct mutex mutex;
+};
+
+enum max77693_muic_charger_type {
+	MAX77693_CHARGER_TYPE_NONE = 0,
+	MAX77693_CHARGER_TYPE_USB,
+	MAX77693_CHARGER_TYPE_DOWNSTREAM_PORT,
+	MAX77693_CHARGER_TYPE_DEDICATED_CHG,
+	MAX77693_CHARGER_TYPE_APPLE_500MA,
+	MAX77693_CHARGER_TYPE_APPLE_1A_2A,
+	MAX77693_CHARGER_TYPE_DEAD_BATTERY = 7,
+};
+
+/**
+ * struct max77693_muic_irq
+ * @irq: the index of irq list of MUIC device.
+ * @name: the name of irq.
+ * @virq: the virtual irq to use irq domain
+ */
+struct max77693_muic_irq {
+	unsigned int irq;
+	const char *name;
+	unsigned int virq;
+};
+
+static struct max77693_muic_irq muic_irqs[] = {
+	{ MAX77693_MUIC_IRQ_INT1_ADC,		"muic-ADC" },
+	{ MAX77693_MUIC_IRQ_INT1_ADC_LOW,	"muic-ADCLOW" },
+	{ MAX77693_MUIC_IRQ_INT1_ADC_ERR,	"muic-ADCError" },
+	{ MAX77693_MUIC_IRQ_INT1_ADC1K,		"muic-ADC1K" },
+	{ MAX77693_MUIC_IRQ_INT2_CHGTYP,	"muic-CHGTYP" },
+	{ MAX77693_MUIC_IRQ_INT2_CHGDETREUN,	"muic-CHGDETREUN" },
+	{ MAX77693_MUIC_IRQ_INT2_DCDTMR,	"muic-DCDTMR" },
+	{ MAX77693_MUIC_IRQ_INT2_DXOVP,		"muic-DXOVP" },
+	{ MAX77693_MUIC_IRQ_INT2_VBVOLT,	"muic-VBVOLT" },
+	{ MAX77693_MUIC_IRQ_INT2_VIDRM,		"muic-VIDRM" },
+	{ MAX77693_MUIC_IRQ_INT3_EOC,		"muic-EOC" },
+	{ MAX77693_MUIC_IRQ_INT3_CGMBC,		"muic-CGMBC" },
+	{ MAX77693_MUIC_IRQ_INT3_OVP,		"muic-OVP" },
+	{ MAX77693_MUIC_IRQ_INT3_MBCCHG_ERR,	"muic-MBCCHG_ERR" },
+	{ MAX77693_MUIC_IRQ_INT3_CHG_ENABLED,	"muic-CHG_ENABLED" },
+	{ MAX77693_MUIC_IRQ_INT3_BAT_DET,	"muic-BAT_DET" },
+};
+
+/* Define supported accessory type */
+enum max77693_muic_acc_type {
+	MAX77693_MUIC_ADC_GROUND = 0x0,
+	MAX77693_MUIC_ADC_SEND_END_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S1_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S2_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S3_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S4_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S5_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S6_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S7_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S8_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S9_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S10_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S11_BUTTON,
+	MAX77693_MUIC_ADC_REMOTE_S12_BUTTON,
+	MAX77693_MUIC_ADC_RESERVED_ACC_1,
+	MAX77693_MUIC_ADC_RESERVED_ACC_2,
+	MAX77693_MUIC_ADC_RESERVED_ACC_3,
+	MAX77693_MUIC_ADC_RESERVED_ACC_4,
+	MAX77693_MUIC_ADC_RESERVED_ACC_5,
+	MAX77693_MUIC_ADC_CEA936_AUDIO,
+	MAX77693_MUIC_ADC_PHONE_POWERED_DEV,
+	MAX77693_MUIC_ADC_TTY_CONVERTER,
+	MAX77693_MUIC_ADC_UART_CABLE,
+	MAX77693_MUIC_ADC_CEA936A_TYPE1_CHG,
+	MAX77693_MUIC_ADC_FACTORY_MODE_USB_OFF,
+	MAX77693_MUIC_ADC_FACTORY_MODE_USB_ON,
+	MAX77693_MUIC_ADC_AV_CABLE_NOLOAD,
+	MAX77693_MUIC_ADC_CEA936A_TYPE2_CHG,
+	MAX77693_MUIC_ADC_FACTORY_MODE_UART_OFF,
+	MAX77693_MUIC_ADC_FACTORY_MODE_UART_ON,
+	MAX77693_MUIC_ADC_AUDIO_MODE_REMOTE,
+	MAX77693_MUIC_ADC_OPEN,
+
+	/* The below accessories have same ADC value so ADCLow and
+	   ADC1K bit is used to separate specific accessory */
+	MAX77693_MUIC_GND_USB_OTG = 0x100,	/* ADC:0x0, ADCLow:0, ADC1K:0 */
+	MAX77693_MUIC_GND_AV_CABLE_LOAD = 0x102,/* ADC:0x0, ADCLow:1, ADC1K:0 */
+	MAX77693_MUIC_GND_MHL_CABLE = 0x103,	/* ADC:0x0, ADCLow:1, ADC1K:1 */
+};
+
+/* MAX77693 MUIC device support below list of accessories(external connector) */
+const char *max77693_extcon_cable[] = {
+	[0] = "USB",
+	[1] = "USB-Host",
+	[2] = "TA",
+	[3] = "Fast-charger",
+	[4] = "Slow-charger",
+	[5] = "Charge-downstream",
+	[6] = "MHL",
+	[7] = "Audio-video-load",
+	[8] = "Audio-video-noload",
+	[9] = "JIG",
+
+	NULL,
+};
+
+static int max77693_muic_set_debounce_time(struct max77693_muic_info *info,
+		enum max77693_muic_adc_debounce_time time)
+{
+	int ret = 0;
+	u8 ctrl3;
+
+	switch (time) {
+	case ADC_DEBOUNCE_TIME_5MS:
+	case ADC_DEBOUNCE_TIME_10MS:
+	case ADC_DEBOUNCE_TIME_25MS:
+	case ADC_DEBOUNCE_TIME_38_62MS:
+		ret = max77693_read_reg(info->max77693->regmap_muic,
+				MAX77693_MUIC_REG_CTRL3, &ctrl3);
+		ctrl3 &= ~CONTROL3_ADCDBSET_MASK;
+		ctrl3 |= (time << CONTROL3_ADCDBSET_SHIFT);
+
+		ret = max77693_write_reg(info->max77693->regmap_muic,
+				MAX77693_MUIC_REG_CTRL3, ctrl3);
+		if (ret) {
+			dev_err(info->dev, "failed to set ADC debounce time\n");
+			ret = -EINVAL;
+		}
+		break;
+	default:
+		dev_err(info->dev, "invalid ADC debounce time\n");
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+};
+
+static int max77693_muic_set_path(struct max77693_muic_info *info,
+		u8 val, bool attached)
+{
+	int ret = 0;
+	u8 ctrl1, ctrl2 = 0;
+
+	if (attached)
+		ctrl1 = val;
+	else
+		ctrl1 = CONTROL1_SW_OPEN;
+
+	ret = max77693_update_reg(info->max77693->regmap_muic,
+			MAX77693_MUIC_REG_CTRL1, ctrl1, COMP_SW_MASK);
+	if (ret < 0) {
+		dev_err(info->dev, "failed to update MUIC register\n");
+		goto out;
+	}
+
+	if (attached)
+		ctrl2 |= CONTROL2_CPEN_MASK;	/* LowPwr=0, CPEn=1 */
+	else
+		ctrl2 |= CONTROL2_LOWPWR_MASK;	/* LowPwr=1, CPEn=0 */
+
+	ret = max77693_update_reg(info->max77693->regmap_muic,
+			MAX77693_MUIC_REG_CTRL2, ctrl2,
+			CONTROL2_LOWPWR_MASK | CONTROL2_CPEN_MASK);
+	if (ret < 0) {
+		dev_err(info->dev, "failed to update MUIC register\n");
+		goto out;
+	}
+
+	dev_info(info->dev,
+		"CONTROL1 : 0x%02x, CONTROL2 : 0x%02x, state : %s\n",
+		ctrl1, ctrl2, attached ? "attached" : "detached");
+out:
+	return ret;
+}
+
+static int max77693_muic_adc_ground_handler(struct max77693_muic_info *info,
+		bool attached)
+{
+	int ret = 0;
+	int type;
+	int adc, adc1k, adclow;
+
+	if (attached) {
+		adc = info->status[0] & STATUS1_ADC_MASK;
+		adclow = info->status[0] & STATUS1_ADCLOW_MASK;
+		adclow >>= STATUS1_ADCLOW_SHIFT;
+		adc1k = info->status[0] & STATUS1_ADC1K_MASK;
+		adc1k >>= STATUS1_ADC1K_SHIFT;
+
+		/**
+		 * [0x1][ADCLow][ADC1K]
+		 * [0x1    0       0  ]	: USB_OTG
+		 * [0x1    1       0  ] : Audio Video Cable with load
+		 * [0x1    1       1  ] : MHL
+		 */
+		type = ((0x1 << 8) | (adclow << 1) | adc1k);
+
+		/* Store previous ADC value to handle accessory
+		   when accessory will be detached */
+		info->prev_adc = adc;
+		info->prev_adc_gnd = type;
+	} else
+		type = info->prev_adc_gnd;
+
+	switch (type) {
+	case MAX77693_MUIC_GND_USB_OTG:
+		/* USB_OTG */
+		ret = max77693_muic_set_path(info, CONTROL1_SW_USB, attached);
+		if (ret < 0)
+			goto out;
+		extcon_set_cable_state(info->edev, "USB-Host", attached);
+		break;
+	case MAX77693_MUIC_GND_AV_CABLE_LOAD:
+		/* Audio Video Cable with load */
+		ret = max77693_muic_set_path(info, CONTROL1_SW_AUDIO, attached);
+		if (ret < 0)
+			goto out;
+		extcon_set_cable_state(info->edev,
+				"Audio-video-load", attached);
+		break;
+	case MAX77693_MUIC_GND_MHL_CABLE:
+		/* MHL */
+		extcon_set_cable_state(info->edev, "MHL", attached);
+		break;
+	default:
+		dev_err(info->dev, "faild to detect %s accessory\n",
+			attached ? "attached" : "detached");
+		dev_err(info->dev, "- adc:0x%x, adclow:0x%x, adc1k:0x%x\n",
+			adc, adclow, adc1k);
+		ret = -EINVAL;
+		break;
+	}
+
+out:
+	return ret;
+}
+
+static int max77693_muic_adc_handler(struct max77693_muic_info *info,
+		int curr_adc, bool attached)
+{
+	int ret = 0;
+	int adc;
+
+	if (attached) {
+		/* Store ADC value to handle accessory
+		   when accessory will be detached */
+		info->prev_adc = curr_adc;
+		adc = curr_adc;
+	} else
+		adc = info->prev_adc;
+
+	dev_info(info->dev,
+		"external connector is %s (adc:0x%02x, prev_adc:0x%x)\n",
+		attached ? "attached" : "detached", curr_adc, info->prev_adc);
+
+	switch (adc) {
+	case MAX77693_MUIC_ADC_GROUND:
+		/* USB_OTG/MHL/Audio */
+		max77693_muic_adc_ground_handler(info, attached);
+		break;
+	case MAX77693_MUIC_ADC_FACTORY_MODE_USB_OFF:
+	case MAX77693_MUIC_ADC_FACTORY_MODE_USB_ON:
+		/* USB */
+		ret = max77693_muic_set_path(info, CONTROL1_SW_USB, attached);
+		if (ret < 0)
+			goto out;
+		extcon_set_cable_state(info->edev, "USB", attached);
+		break;
+	case MAX77693_MUIC_ADC_FACTORY_MODE_UART_OFF:
+	case MAX77693_MUIC_ADC_FACTORY_MODE_UART_ON:
+		/* JIG */
+		ret = max77693_muic_set_path(info, CONTROL1_SW_UART, attached);
+		if (ret < 0)
+			goto out;
+		extcon_set_cable_state(info->edev, "JIG", attached);
+		break;
+	case MAX77693_MUIC_ADC_AUDIO_MODE_REMOTE:
+		/* Audio Video cable with no-load */
+		ret = max77693_muic_set_path(info, CONTROL1_SW_AUDIO, attached);
+		if (ret < 0)
+			goto out;
+		extcon_set_cable_state(info->edev,
+				"Audio-video-noload", attached);
+		break;
+	case MAX77693_MUIC_ADC_SEND_END_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S1_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S2_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S3_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S4_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S5_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S6_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S7_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S8_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S9_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S10_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S11_BUTTON:
+	case MAX77693_MUIC_ADC_REMOTE_S12_BUTTON:
+	case MAX77693_MUIC_ADC_RESERVED_ACC_1:
+	case MAX77693_MUIC_ADC_RESERVED_ACC_2:
+	case MAX77693_MUIC_ADC_RESERVED_ACC_3:
+	case MAX77693_MUIC_ADC_RESERVED_ACC_4:
+	case MAX77693_MUIC_ADC_RESERVED_ACC_5:
+	case MAX77693_MUIC_ADC_CEA936_AUDIO:
+	case MAX77693_MUIC_ADC_PHONE_POWERED_DEV:
+	case MAX77693_MUIC_ADC_TTY_CONVERTER:
+	case MAX77693_MUIC_ADC_UART_CABLE:
+	case MAX77693_MUIC_ADC_CEA936A_TYPE1_CHG:
+	case MAX77693_MUIC_ADC_AV_CABLE_NOLOAD:
+	case MAX77693_MUIC_ADC_CEA936A_TYPE2_CHG:
+		/* This accessory isn't used in general case if it is specially
+		   needed to detect additional accessory, should implement
+		   proper operation when this accessory is attached/detached. */
+		dev_info(info->dev,
+			"accessory is %s but it isn't used (adc:0x%x)\n",
+			attached ? "attached" : "detached", adc);
+		goto out;
+	default:
+		dev_err(info->dev,
+			"failed to detect %s accessory (adc:0x%x)\n",
+			attached ? "attached" : "detached", adc);
+		ret = -EINVAL;
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
+static int max77693_muic_chg_handler(struct max77693_muic_info *info,
+		int curr_chg_type, bool attached)
+{
+	int ret = 0;
+	int chg_type;
+
+	if (attached) {
+		/* Store previous charger type to control
+		   when charger accessory will be detached */
+		info->prev_chg_type = curr_chg_type;
+		chg_type = curr_chg_type;
+	} else
+		chg_type = info->prev_chg_type;
+
+	dev_info(info->dev,
+		"external connector is %s(chg_type:0x%x, prev_chg_type:0x%x)\n",
+			attached ? "attached" : "detached",
+			curr_chg_type, info->prev_chg_type);
+
+	switch (chg_type) {
+	case MAX77693_CHARGER_TYPE_USB:
+		ret = max77693_muic_set_path(info, CONTROL1_SW_USB, attached);
+		if (ret < 0)
+			goto out;
+		extcon_set_cable_state(info->edev, "USB", attached);
+		break;
+	case MAX77693_CHARGER_TYPE_DOWNSTREAM_PORT:
+		extcon_set_cable_state(info->edev,
+				"Charge-downstream", attached);
+		break;
+	case MAX77693_CHARGER_TYPE_DEDICATED_CHG:
+		extcon_set_cable_state(info->edev, "TA", attached);
+		break;
+	case MAX77693_CHARGER_TYPE_APPLE_500MA:
+		extcon_set_cable_state(info->edev, "Slow-charger", attached);
+		break;
+	case MAX77693_CHARGER_TYPE_APPLE_1A_2A:
+		extcon_set_cable_state(info->edev, "Fast-charger", attached);
+		break;
+	case MAX77693_CHARGER_TYPE_DEAD_BATTERY:
+		break;
+	default:
+		dev_err(info->dev,
+			"failed to detect %s accessory (chg_type:0x%x)\n",
+			attached ? "attached" : "detached", chg_type);
+		ret = -EINVAL;
+		goto out;
+	}
+
+out:
+	return ret;
+}
+
+static void max77693_muic_irq_work(struct work_struct *work)
+{
+	struct max77693_muic_info *info = container_of(work,
+			struct max77693_muic_info, irq_work);
+	int curr_adc, curr_chg_type;
+	int irq_type = -1;
+	int i, ret = 0;
+	bool attached = true;
+
+	if (!info->edev)
+		return;
+
+	mutex_lock(&info->mutex);
+
+	for (i = 0 ; i < ARRAY_SIZE(muic_irqs) ; i++)
+		if (info->irq == muic_irqs[i].virq)
+			irq_type = muic_irqs[i].irq;
+
+	ret = max77693_bulk_read(info->max77693->regmap_muic,
+			MAX77693_MUIC_REG_STATUS1, 2, info->status);
+	if (ret) {
+		dev_err(info->dev, "failed to read MUIC register\n");
+		mutex_unlock(&info->mutex);
+		return;
+	}
+
+	switch (irq_type) {
+	case MAX77693_MUIC_IRQ_INT1_ADC:
+	case MAX77693_MUIC_IRQ_INT1_ADC_LOW:
+	case MAX77693_MUIC_IRQ_INT1_ADC_ERR:
+	case MAX77693_MUIC_IRQ_INT1_ADC1K:
+		/* Handle all of accessory except for
+		   type of charger accessory */
+		curr_adc = info->status[0] & STATUS1_ADC_MASK;
+		curr_adc >>= STATUS1_ADC_SHIFT;
+
+		/* Check accossory state which is either detached or attached */
+		if (curr_adc == MAX77693_MUIC_ADC_OPEN)
+			attached = false;
+
+		ret = max77693_muic_adc_handler(info, curr_adc, attached);
+		break;
+	case MAX77693_MUIC_IRQ_INT2_CHGTYP:
+	case MAX77693_MUIC_IRQ_INT2_CHGDETREUN:
+	case MAX77693_MUIC_IRQ_INT2_DCDTMR:
+	case MAX77693_MUIC_IRQ_INT2_DXOVP:
+	case MAX77693_MUIC_IRQ_INT2_VBVOLT:
+	case MAX77693_MUIC_IRQ_INT2_VIDRM:
+		/* Handle charger accessory */
+		curr_chg_type = info->status[1] & STATUS2_CHGTYP_MASK;
+		curr_chg_type >>= STATUS2_CHGTYP_SHIFT;
+
+		/* Check charger accossory state which
+		   is either detached or attached */
+		if (curr_chg_type == MAX77693_CHARGER_TYPE_NONE)
+			attached = false;
+
+		ret = max77693_muic_chg_handler(info, curr_chg_type, attached);
+		break;
+	case MAX77693_MUIC_IRQ_INT3_EOC:
+	case MAX77693_MUIC_IRQ_INT3_CGMBC:
+	case MAX77693_MUIC_IRQ_INT3_OVP:
+	case MAX77693_MUIC_IRQ_INT3_MBCCHG_ERR:
+	case MAX77693_MUIC_IRQ_INT3_CHG_ENABLED:
+	case MAX77693_MUIC_IRQ_INT3_BAT_DET:
+		break;
+	default:
+		dev_err(info->dev, "muic interrupt: irq %d occurred\n",
+				irq_type);
+		break;
+	}
+
+	if (ret < 0)
+		dev_err(info->dev, "failed to handle MUIC interrupt\n");
+
+	mutex_unlock(&info->mutex);
+
+	return;
+}
+
+static irqreturn_t max77693_muic_irq_handler(int irq, void *data)
+{
+	struct max77693_muic_info *info = data;
+
+	info->irq = irq;
+	schedule_work(&info->irq_work);
+
+	return IRQ_HANDLED;
+}
+
+static struct regmap_config max77693_muic_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
+static int max77693_muic_detect_accessory(struct max77693_muic_info *info)
+{
+	int ret = 0;
+	int adc, chg_type;
+
+	mutex_lock(&info->mutex);
+
+	/* Read STATUSx register to detect accessory */
+	ret = max77693_bulk_read(info->max77693->regmap_muic,
+			MAX77693_MUIC_REG_STATUS1, 2, info->status);
+	if (ret) {
+		dev_err(info->dev, "failed to read MUIC register\n");
+		mutex_unlock(&info->mutex);
+		return -EINVAL;
+	}
+
+	adc = info->status[0] & STATUS1_ADC_MASK;
+	adc >>= STATUS1_ADC_SHIFT;
+
+	if (adc != MAX77693_MUIC_ADC_OPEN) {
+		dev_info(info->dev,
+			"external connector is attached (adc:0x%02x)\n", adc);
+
+		ret = max77693_muic_adc_handler(info, adc, true);
+		if (ret < 0)
+			dev_err(info->dev, "failed to detect accessory\n");
+		goto out;
+	}
+
+	chg_type = info->status[1] & STATUS2_CHGTYP_MASK;
+	chg_type >>= STATUS2_CHGTYP_SHIFT;
+
+	if (chg_type != MAX77693_CHARGER_TYPE_NONE) {
+		dev_info(info->dev,
+			"external connector is attached (chg_type:0x%x)\n",
+			chg_type);
+
+		max77693_muic_chg_handler(info, chg_type, true);
+		if (ret < 0)
+			dev_err(info->dev, "failed to detect charger accessory\n");
+	}
+
+out:
+	mutex_unlock(&info->mutex);
+	return ret;
+}
+
+static int __devinit max77693_muic_probe(struct platform_device *pdev)
+{
+	struct max77693_dev *max77693 = dev_get_drvdata(pdev->dev.parent);
+	struct max77693_muic_info *info;
+	int ret, i;
+	u8 id;
+
+	info = kzalloc(sizeof(struct max77693_muic_info), GFP_KERNEL);
+	if (!info) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		ret = -ENOMEM;
+		goto err_kfree;
+	}
+	info->dev = &pdev->dev;
+	info->max77693 = max77693;
+	info->max77693->regmap_muic = regmap_init_i2c(info->max77693->muic,
+					 &max77693_muic_regmap_config);
+	if (IS_ERR(info->max77693->regmap_muic)) {
+		ret = PTR_ERR(info->max77693->regmap_muic);
+		dev_err(max77693->dev,
+			"failed to allocate register map: %d\n", ret);
+		goto err_regmap;
+	}
+	platform_set_drvdata(pdev, info);
+	mutex_init(&info->mutex);
+
+	INIT_WORK(&info->irq_work, max77693_muic_irq_work);
+
+	/* Support irq domain for MAX77693 MUIC device */
+	for (i = 0; i < ARRAY_SIZE(muic_irqs); i++) {
+		struct max77693_muic_irq *muic_irq = &muic_irqs[i];
+		int virq = 0;
+
+		virq = irq_create_mapping(max77693->irq_domain, muic_irq->irq);
+		if (!virq)
+			goto err_irq;
+		muic_irq->virq = virq;
+
+		ret = request_threaded_irq(virq, NULL,
+				max77693_muic_irq_handler,
+				0, muic_irq->name, info);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"failed: irq request (IRQ: %d,"
+				" error :%d)\n",
+				muic_irq->irq, ret);
+
+			for (i = i - 1; i >= 0; i--)
+				free_irq(muic_irq->virq, info);
+			goto err_irq;
+		}
+	}
+
+	/* Initialize extcon device */
+	info->edev = kzalloc(sizeof(struct extcon_dev), GFP_KERNEL);
+	if (!info->edev) {
+		dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
+		ret = -ENOMEM;
+		goto err_irq;
+	}
+	info->edev->name = DEV_NAME;
+	info->edev->supported_cable = max77693_extcon_cable;
+	ret = extcon_dev_register(info->edev, NULL);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register extcon device\n");
+		goto err_extcon;
+	}
+
+	/* Check revision number of MUIC device*/
+	ret = max77693_read_reg(info->max77693->regmap_muic,
+			MAX77693_MUIC_REG_ID, &id);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to read revision number\n");
+		goto err_extcon;
+	}
+	dev_info(info->dev, "device ID : 0x%x\n", id);
+
+	/* Set ADC debounce time */
+	max77693_muic_set_debounce_time(info, ADC_DEBOUNCE_TIME_25MS);
+
+	/* Detect accessory on boot */
+	max77693_muic_detect_accessory(info);
+
+	return ret;
+
+err_extcon:
+	kfree(info->edev);
+err_irq:
+err_regmap:
+	kfree(info);
+err_kfree:
+	return ret;
+}
+
+static int __devexit max77693_muic_remove(struct platform_device *pdev)
+{
+	struct max77693_muic_info *info = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(muic_irqs); i++)
+		free_irq(muic_irqs[i].virq, info);
+	cancel_work_sync(&info->irq_work);
+	extcon_dev_unregister(info->edev);
+	kfree(info);
+
+	return 0;
+}
+
+static struct platform_driver max77693_muic_driver = {
+	.driver		= {
+		.name	= DEV_NAME,
+		.owner	= THIS_MODULE,
+	},
+	.probe		= max77693_muic_probe,
+	.remove		= __devexit_p(max77693_muic_remove),
+};
+
+module_platform_driver(max77693_muic_driver);
+
+MODULE_DESCRIPTION("Maxim MAX77693 Extcon driver");
+MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:extcon-max77693");