/*
 * Copyright (C) 2013 Samsung Electronics Co., Ltd.
 * Author: Beomho Seo <beomho.seo@samsung.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/delay.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/regulator/consumer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>

/* Slave address 0x19 for PS of 7 bit addressing protocol for I2C */
#define CM36651_I2C_ADDR_PS		0x19
/* Alert Response Address */
#define CM36651_ARA			0x0C

/* Ambient light sensor */
#define CM36651_CS_CONF1		0x00
#define CM36651_CS_CONF2		0x01
#define CM36651_ALS_WH_M		0x02
#define CM36651_ALS_WH_L		0x03
#define CM36651_ALS_WL_M		0x04
#define CM36651_ALS_WL_L		0x05
#define CM36651_CS_CONF3		0x06
#define CM36651_CS_CONF_REG_NUM		0x02

/* Proximity sensor */
#define CM36651_PS_CONF1		0x00
#define CM36651_PS_THD			0x01
#define CM36651_PS_CANC			0x02
#define CM36651_PS_CONF2		0x03
#define CM36651_PS_REG_NUM		0x04

/* CS_CONF1 command code */
#define CM36651_ALS_ENABLE		0x00
#define CM36651_ALS_DISABLE		0x01
#define CM36651_ALS_INT_EN		0x02
#define CM36651_ALS_THRES		0x04

/* CS_CONF2 command code */
#define CM36651_CS_CONF2_DEFAULT_BIT	0x08

/* CS_CONF3 channel integration time */
#define CM36651_CS_IT1			0x00 /* Integration time 80 msec */
#define CM36651_CS_IT2			0x40 /* Integration time 160 msec */
#define CM36651_CS_IT3			0x80 /* Integration time 320 msec */
#define CM36651_CS_IT4			0xC0 /* Integration time 640 msec */

/* PS_CONF1 command code */
#define CM36651_PS_ENABLE		0x00
#define CM36651_PS_DISABLE		0x01
#define CM36651_PS_INT_EN		0x02
#define CM36651_PS_PERS2		0x04
#define CM36651_PS_PERS3		0x08
#define CM36651_PS_PERS4		0x0C

/* PS_CONF1 command code: integration time */
#define CM36651_PS_IT1			0x00 /* Integration time 0.32 msec */
#define CM36651_PS_IT2			0x10 /* Integration time 0.42 msec */
#define CM36651_PS_IT3			0x20 /* Integration time 0.52 msec */
#define CM36651_PS_IT4			0x30 /* Integration time 0.64 msec */

/* PS_CONF1 command code: duty ratio */
#define CM36651_PS_DR1			0x00 /* Duty ratio 1/80 */
#define CM36651_PS_DR2			0x40 /* Duty ratio 1/160 */
#define CM36651_PS_DR3			0x80 /* Duty ratio 1/320 */
#define CM36651_PS_DR4			0xC0 /* Duty ratio 1/640 */

/* PS_THD command code */
#define CM36651_PS_INITIAL_THD		0x05

/* PS_CANC command code */
#define CM36651_PS_CANC_DEFAULT		0x00

/* PS_CONF2 command code */
#define CM36651_PS_HYS1			0x00
#define CM36651_PS_HYS2			0x01
#define CM36651_PS_SMART_PERS_EN	0x02
#define CM36651_PS_DIR_INT		0x04
#define CM36651_PS_MS			0x10

#define CM36651_CS_COLOR_NUM		4

#define CM36651_CLOSE_PROXIMITY		0x32
#define CM36651_FAR_PROXIMITY			0x33

#define CM36651_CS_INT_TIME_AVAIL	"0.08 0.16 0.32 0.64"
#define CM36651_PS_INT_TIME_AVAIL	"0.000320 0.000420 0.000520 0.000640"

enum cm36651_operation_mode {
	CM36651_LIGHT_EN,
	CM36651_PROXIMITY_EN,
	CM36651_PROXIMITY_EV_EN,
};

enum cm36651_light_channel_idx {
	CM36651_LIGHT_CHANNEL_IDX_RED,
	CM36651_LIGHT_CHANNEL_IDX_GREEN,
	CM36651_LIGHT_CHANNEL_IDX_BLUE,
	CM36651_LIGHT_CHANNEL_IDX_CLEAR,
};

enum cm36651_command {
	CM36651_CMD_READ_RAW_LIGHT,
	CM36651_CMD_READ_RAW_PROXIMITY,
	CM36651_CMD_PROX_EV_EN,
	CM36651_CMD_PROX_EV_DIS,
};

static const u8 cm36651_cs_reg[CM36651_CS_CONF_REG_NUM] = {
	CM36651_CS_CONF1,
	CM36651_CS_CONF2,
};

static const u8 cm36651_ps_reg[CM36651_PS_REG_NUM] = {
	CM36651_PS_CONF1,
	CM36651_PS_THD,
	CM36651_PS_CANC,
	CM36651_PS_CONF2,
};

struct cm36651_data {
	const struct cm36651_platform_data *pdata;
	struct i2c_client *client;
	struct i2c_client *ps_client;
	struct i2c_client *ara_client;
	struct mutex lock;
	struct regulator *vled_reg;
	unsigned long flags;
	int cs_int_time[CM36651_CS_COLOR_NUM];
	int ps_int_time;
	u8 cs_ctrl_regs[CM36651_CS_CONF_REG_NUM];
	u8 ps_ctrl_regs[CM36651_PS_REG_NUM];
	u16 color[CM36651_CS_COLOR_NUM];
};

static int cm36651_setup_reg(struct cm36651_data *cm36651)
{
	struct i2c_client *client = cm36651->client;
	struct i2c_client *ps_client = cm36651->ps_client;
	int i, ret;

	/* CS initialization */
	cm36651->cs_ctrl_regs[CM36651_CS_CONF1] = CM36651_ALS_ENABLE |
							     CM36651_ALS_THRES;
	cm36651->cs_ctrl_regs[CM36651_CS_CONF2] = CM36651_CS_CONF2_DEFAULT_BIT;

	for (i = 0; i < CM36651_CS_CONF_REG_NUM; i++) {
		ret = i2c_smbus_write_byte_data(client, cm36651_cs_reg[i],
						     cm36651->cs_ctrl_regs[i]);
		if (ret < 0)
			return ret;
	}

	/* PS initialization */
	cm36651->ps_ctrl_regs[CM36651_PS_CONF1] = CM36651_PS_ENABLE |
								CM36651_PS_IT2;
	cm36651->ps_ctrl_regs[CM36651_PS_THD] = CM36651_PS_INITIAL_THD;
	cm36651->ps_ctrl_regs[CM36651_PS_CANC] = CM36651_PS_CANC_DEFAULT;
	cm36651->ps_ctrl_regs[CM36651_PS_CONF2] = CM36651_PS_HYS2 |
				CM36651_PS_DIR_INT | CM36651_PS_SMART_PERS_EN;

	for (i = 0; i < CM36651_PS_REG_NUM; i++) {
		ret = i2c_smbus_write_byte_data(ps_client, cm36651_ps_reg[i],
						     cm36651->ps_ctrl_regs[i]);
		if (ret < 0)
			return ret;
	}

	/* Set shutdown mode */
	ret = i2c_smbus_write_byte_data(client, CM36651_CS_CONF1,
							  CM36651_ALS_DISABLE);
	if (ret < 0)
		return ret;

	ret = i2c_smbus_write_byte_data(cm36651->ps_client,
					 CM36651_PS_CONF1, CM36651_PS_DISABLE);
	if (ret < 0)
		return ret;

	return 0;
}

static int cm36651_read_output(struct cm36651_data *cm36651,
				struct iio_chan_spec const *chan, int *val)
{
	struct i2c_client *client = cm36651->client;
	int ret = -EINVAL;

	switch (chan->type) {
	case IIO_LIGHT:
		*val = i2c_smbus_read_word_data(client, chan->address);
		if (*val < 0)
			return ret;

		ret = i2c_smbus_write_byte_data(client, CM36651_CS_CONF1,
							CM36651_ALS_DISABLE);
		if (ret < 0)
			return ret;

		ret = IIO_VAL_INT;
		break;
	case IIO_PROXIMITY:
		*val = i2c_smbus_read_byte(cm36651->ps_client);
		if (*val < 0)
			return ret;

		if (!test_bit(CM36651_PROXIMITY_EV_EN, &cm36651->flags)) {
			ret = i2c_smbus_write_byte_data(cm36651->ps_client,
					CM36651_PS_CONF1, CM36651_PS_DISABLE);
			if (ret < 0)
				return ret;
		}

		ret = IIO_VAL_INT;
		break;
	default:
		break;
	}

	return ret;
}

static irqreturn_t cm36651_irq_handler(int irq, void *data)
{
	struct iio_dev *indio_dev = data;
	struct cm36651_data *cm36651 = iio_priv(indio_dev);
	struct i2c_client *client = cm36651->client;
	int ev_dir, ret;
	u64 ev_code;

	/*
	 * The PS INT pin is an active low signal that PS INT move logic low
	 * when the object is detect. Once the MCU host received the PS INT
	 * "LOW" signal, the Host needs to read the data at Alert Response
	 * Address(ARA) to clear the PS INT signal. After clearing the PS
	 * INT pin, the PS INT signal toggles from low to high.
	 */
	ret = i2c_smbus_read_byte(cm36651->ara_client);
	if (ret < 0) {
		dev_err(&client->dev,
				"%s: Data read failed: %d\n", __func__, ret);
		return IRQ_HANDLED;
	}
	switch (ret) {
	case CM36651_CLOSE_PROXIMITY:
		ev_dir = IIO_EV_DIR_RISING;
		break;
	case CM36651_FAR_PROXIMITY:
		ev_dir = IIO_EV_DIR_FALLING;
		break;
	default:
		dev_err(&client->dev,
			"%s: Data read wrong: %d\n", __func__, ret);
		return IRQ_HANDLED;
	}

	ev_code = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY,
				CM36651_CMD_READ_RAW_PROXIMITY,
				IIO_EV_TYPE_THRESH, ev_dir);

	iio_push_event(indio_dev, ev_code, iio_get_time_ns());

	return IRQ_HANDLED;
}

static int cm36651_set_operation_mode(struct cm36651_data *cm36651, int cmd)
{
	struct i2c_client *client = cm36651->client;
	struct i2c_client *ps_client = cm36651->ps_client;
	int ret = -EINVAL;

	switch (cmd) {
	case CM36651_CMD_READ_RAW_LIGHT:
		ret = i2c_smbus_write_byte_data(client, CM36651_CS_CONF1,
				cm36651->cs_ctrl_regs[CM36651_CS_CONF1]);
		break;
	case CM36651_CMD_READ_RAW_PROXIMITY:
		if (test_bit(CM36651_PROXIMITY_EV_EN, &cm36651->flags))
			return CM36651_PROXIMITY_EV_EN;

		ret = i2c_smbus_write_byte_data(ps_client, CM36651_PS_CONF1,
				cm36651->ps_ctrl_regs[CM36651_PS_CONF1]);
		break;
	case CM36651_CMD_PROX_EV_EN:
		if (test_bit(CM36651_PROXIMITY_EV_EN, &cm36651->flags)) {
			dev_err(&client->dev,
				"Already proximity event enable state\n");
			return ret;
		}
		set_bit(CM36651_PROXIMITY_EV_EN, &cm36651->flags);

		ret = i2c_smbus_write_byte_data(ps_client,
			cm36651_ps_reg[CM36651_PS_CONF1],
			CM36651_PS_INT_EN | CM36651_PS_PERS2 | CM36651_PS_IT2);

		if (ret < 0) {
			dev_err(&client->dev, "Proximity enable event failed\n");
			return ret;
		}
		break;
	case CM36651_CMD_PROX_EV_DIS:
		if (!test_bit(CM36651_PROXIMITY_EV_EN, &cm36651->flags)) {
			dev_err(&client->dev,
				"Already proximity event disable state\n");
			return ret;
		}
		clear_bit(CM36651_PROXIMITY_EV_EN, &cm36651->flags);
		ret = i2c_smbus_write_byte_data(ps_client,
					CM36651_PS_CONF1, CM36651_PS_DISABLE);
		break;
	}

	if (ret < 0)
		dev_err(&client->dev, "Write register failed\n");

	return ret;
}

static int cm36651_read_channel(struct cm36651_data *cm36651,
				struct iio_chan_spec const *chan, int *val)
{
	struct i2c_client *client = cm36651->client;
	int cmd, ret;

	if (chan->type == IIO_LIGHT)
		cmd = CM36651_CMD_READ_RAW_LIGHT;
	else if (chan->type == IIO_PROXIMITY)
		cmd = CM36651_CMD_READ_RAW_PROXIMITY;
	else
		return -EINVAL;

	ret = cm36651_set_operation_mode(cm36651, cmd);
	if (ret < 0) {
		dev_err(&client->dev, "CM36651 set operation mode failed\n");
		return ret;
	}
	/* Delay for work after enable operation */
	msleep(50);
	ret = cm36651_read_output(cm36651, chan, val);
	if (ret < 0) {
		dev_err(&client->dev, "CM36651 read output failed\n");
		return ret;
	}

	return ret;
}

static int cm36651_read_int_time(struct cm36651_data *cm36651,
				struct iio_chan_spec const *chan, int *val2)
{
	switch (chan->type) {
	case IIO_LIGHT:
		if (cm36651->cs_int_time[chan->address] == CM36651_CS_IT1)
			*val2 = 80000;
		else if (cm36651->cs_int_time[chan->address] == CM36651_CS_IT2)
			*val2 = 160000;
		else if (cm36651->cs_int_time[chan->address] == CM36651_CS_IT3)
			*val2 = 320000;
		else if (cm36651->cs_int_time[chan->address] == CM36651_CS_IT4)
			*val2 = 640000;
		else
			return -EINVAL;
		break;
	case IIO_PROXIMITY:
		if (cm36651->ps_int_time == CM36651_PS_IT1)
			*val2 = 320;
		else if (cm36651->ps_int_time == CM36651_PS_IT2)
			*val2 = 420;
		else if (cm36651->ps_int_time == CM36651_PS_IT3)
			*val2 = 520;
		else if (cm36651->ps_int_time == CM36651_PS_IT4)
			*val2 = 640;
		else
			return -EINVAL;
		break;
	default:
		return -EINVAL;
	}

	return IIO_VAL_INT_PLUS_MICRO;
}

static int cm36651_write_int_time(struct cm36651_data *cm36651,
				struct iio_chan_spec const *chan, int val)
{
	struct i2c_client *client = cm36651->client;
	struct i2c_client *ps_client = cm36651->ps_client;
	int int_time, ret;

	switch (chan->type) {
	case IIO_LIGHT:
		if (val == 80000)
			int_time = CM36651_CS_IT1;
		else if (val == 160000)
			int_time = CM36651_CS_IT2;
		else if (val == 320000)
			int_time = CM36651_CS_IT3;
		else if (val == 640000)
			int_time = CM36651_CS_IT4;
		else
			return -EINVAL;

		ret = i2c_smbus_write_byte_data(client, CM36651_CS_CONF3,
					   int_time >> 2 * (chan->address));
		if (ret < 0) {
			dev_err(&client->dev, "CS integration time write failed\n");
			return ret;
		}
		cm36651->cs_int_time[chan->address] = int_time;
		break;
	case IIO_PROXIMITY:
		if (val == 320)
			int_time = CM36651_PS_IT1;
		else if (val == 420)
			int_time = CM36651_PS_IT2;
		else if (val == 520)
			int_time = CM36651_PS_IT3;
		else if (val == 640)
			int_time = CM36651_PS_IT4;
		else
			return -EINVAL;

		ret = i2c_smbus_write_byte_data(ps_client,
						CM36651_PS_CONF1, int_time);
		if (ret < 0) {
			dev_err(&client->dev, "PS integration time write failed\n");
			return ret;
		}
		cm36651->ps_int_time = int_time;
		break;
	default:
		return -EINVAL;
	}

	return ret;
}

static int cm36651_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int *val, int *val2, long mask)
{
	struct cm36651_data *cm36651 = iio_priv(indio_dev);
	int ret;

	mutex_lock(&cm36651->lock);

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		ret = cm36651_read_channel(cm36651, chan, val);
		break;
	case IIO_CHAN_INFO_INT_TIME:
		*val = 0;
		ret = cm36651_read_int_time(cm36651, chan, val2);
		break;
	default:
		ret = -EINVAL;
	}

	mutex_unlock(&cm36651->lock);

	return ret;
}

static int cm36651_write_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     int val, int val2, long mask)
{
	struct cm36651_data *cm36651 = iio_priv(indio_dev);
	struct i2c_client *client = cm36651->client;
	int ret = -EINVAL;

	if (mask == IIO_CHAN_INFO_INT_TIME) {
		ret = cm36651_write_int_time(cm36651, chan, val2);
		if (ret < 0)
			dev_err(&client->dev, "Integration time write failed\n");
	}

	return ret;
}

static int cm36651_read_prox_thresh(struct iio_dev *indio_dev,
					const struct iio_chan_spec *chan,
					enum iio_event_type type,
					enum iio_event_direction dir,
					enum iio_event_info info,
					int *val, int *val2)
{
	struct cm36651_data *cm36651 = iio_priv(indio_dev);

	*val = cm36651->ps_ctrl_regs[CM36651_PS_THD];

	return 0;
}

static int cm36651_write_prox_thresh(struct iio_dev *indio_dev,
					const struct iio_chan_spec *chan,
					enum iio_event_type type,
					enum iio_event_direction dir,
					enum iio_event_info info,
					int val, int val2)
{
	struct cm36651_data *cm36651 = iio_priv(indio_dev);
	struct i2c_client *client = cm36651->client;
	int ret;

	if (val < 3 || val > 255)
		return -EINVAL;

	cm36651->ps_ctrl_regs[CM36651_PS_THD] = val;
	ret = i2c_smbus_write_byte_data(cm36651->ps_client, CM36651_PS_THD,
					cm36651->ps_ctrl_regs[CM36651_PS_THD]);

	if (ret < 0) {
		dev_err(&client->dev, "PS threshold write failed: %d\n", ret);
		return ret;
	}

	return 0;
}

static int cm36651_write_prox_event_config(struct iio_dev *indio_dev,
					const struct iio_chan_spec *chan,
					enum iio_event_type type,
					enum iio_event_direction dir,
					int state)
{
	struct cm36651_data *cm36651 = iio_priv(indio_dev);
	int cmd, ret = -EINVAL;

	mutex_lock(&cm36651->lock);

	cmd = state ? CM36651_CMD_PROX_EV_EN : CM36651_CMD_PROX_EV_DIS;
	ret = cm36651_set_operation_mode(cm36651, cmd);

	mutex_unlock(&cm36651->lock);

	return ret;
}

static int cm36651_read_prox_event_config(struct iio_dev *indio_dev,
					const struct iio_chan_spec *chan,
					enum iio_event_type type,
					enum iio_event_direction dir)
{
	struct cm36651_data *cm36651 = iio_priv(indio_dev);
	int event_en;

	mutex_lock(&cm36651->lock);

	event_en = test_bit(CM36651_PROXIMITY_EV_EN, &cm36651->flags);

	mutex_unlock(&cm36651->lock);

	return event_en;
}

#define CM36651_LIGHT_CHANNEL(_color, _idx) {		\
	.type = IIO_LIGHT,				\
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |	\
			BIT(IIO_CHAN_INFO_INT_TIME),	\
	.address = _idx,				\
	.modified = 1,					\
	.channel2 = IIO_MOD_LIGHT_##_color,		\
}							\

static const struct iio_event_spec cm36651_event_spec[] = {
	{
		.type = IIO_EV_TYPE_THRESH,
		.dir = IIO_EV_DIR_EITHER,
		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
				BIT(IIO_EV_INFO_ENABLE),
	}
};

static const struct iio_chan_spec cm36651_channels[] = {
	{
		.type = IIO_PROXIMITY,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
				BIT(IIO_CHAN_INFO_INT_TIME),
		.event_spec = cm36651_event_spec,
		.num_event_specs = ARRAY_SIZE(cm36651_event_spec),
	},
	CM36651_LIGHT_CHANNEL(RED, CM36651_LIGHT_CHANNEL_IDX_RED),
	CM36651_LIGHT_CHANNEL(GREEN, CM36651_LIGHT_CHANNEL_IDX_GREEN),
	CM36651_LIGHT_CHANNEL(BLUE, CM36651_LIGHT_CHANNEL_IDX_BLUE),
	CM36651_LIGHT_CHANNEL(CLEAR, CM36651_LIGHT_CHANNEL_IDX_CLEAR),
};

static IIO_CONST_ATTR(in_illuminance_integration_time_available,
					CM36651_CS_INT_TIME_AVAIL);
static IIO_CONST_ATTR(in_proximity_integration_time_available,
					CM36651_PS_INT_TIME_AVAIL);

static struct attribute *cm36651_attributes[] = {
	&iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr,
	&iio_const_attr_in_proximity_integration_time_available.dev_attr.attr,
	NULL,
};

static const struct attribute_group cm36651_attribute_group = {
	.attrs = cm36651_attributes
};

static const struct iio_info cm36651_info = {
	.driver_module		= THIS_MODULE,
	.read_raw		= &cm36651_read_raw,
	.write_raw		= &cm36651_write_raw,
	.read_event_value	= &cm36651_read_prox_thresh,
	.write_event_value	= &cm36651_write_prox_thresh,
	.read_event_config	= &cm36651_read_prox_event_config,
	.write_event_config	= &cm36651_write_prox_event_config,
	.attrs			= &cm36651_attribute_group,
};

static int cm36651_probe(struct i2c_client *client,
			     const struct i2c_device_id *id)
{
	struct cm36651_data *cm36651;
	struct iio_dev *indio_dev;
	int ret;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*cm36651));
	if (!indio_dev)
		return -ENOMEM;

	cm36651 = iio_priv(indio_dev);

	cm36651->vled_reg = devm_regulator_get(&client->dev, "vled");
	if (IS_ERR(cm36651->vled_reg)) {
		dev_err(&client->dev, "get regulator vled failed\n");
		return PTR_ERR(cm36651->vled_reg);
	}

	ret = regulator_enable(cm36651->vled_reg);
	if (ret) {
		dev_err(&client->dev, "enable regulator vled failed\n");
		return ret;
	}

	i2c_set_clientdata(client, indio_dev);

	cm36651->client = client;
	cm36651->ps_client = i2c_new_dummy(client->adapter,
						     CM36651_I2C_ADDR_PS);
	if (!cm36651->ps_client) {
		dev_err(&client->dev, "%s: new i2c device failed\n", __func__);
		ret = -ENODEV;
		goto error_disable_reg;
	}

	cm36651->ara_client = i2c_new_dummy(client->adapter, CM36651_ARA);
	if (!cm36651->ara_client) {
		dev_err(&client->dev, "%s: new i2c device failed\n", __func__);
		ret = -ENODEV;
		goto error_i2c_unregister_ps;
	}

	mutex_init(&cm36651->lock);
	indio_dev->dev.parent = &client->dev;
	indio_dev->channels = cm36651_channels;
	indio_dev->num_channels = ARRAY_SIZE(cm36651_channels);
	indio_dev->info = &cm36651_info;
	indio_dev->name = id->name;
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = cm36651_setup_reg(cm36651);
	if (ret) {
		dev_err(&client->dev, "%s: register setup failed\n", __func__);
		goto error_i2c_unregister_ara;
	}

	ret = request_threaded_irq(client->irq, NULL, cm36651_irq_handler,
					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
							"cm36651", indio_dev);
	if (ret) {
		dev_err(&client->dev, "%s: request irq failed\n", __func__);
		goto error_i2c_unregister_ara;
	}

	ret = iio_device_register(indio_dev);
	if (ret) {
		dev_err(&client->dev, "%s: regist device failed\n", __func__);
		goto error_free_irq;
	}

	return 0;

error_free_irq:
	free_irq(client->irq, indio_dev);
error_i2c_unregister_ara:
	i2c_unregister_device(cm36651->ara_client);
error_i2c_unregister_ps:
	i2c_unregister_device(cm36651->ps_client);
error_disable_reg:
	regulator_disable(cm36651->vled_reg);
	return ret;
}

static int cm36651_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct cm36651_data *cm36651 = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);
	regulator_disable(cm36651->vled_reg);
	free_irq(client->irq, indio_dev);
	i2c_unregister_device(cm36651->ps_client);
	i2c_unregister_device(cm36651->ara_client);

	return 0;
}

static const struct i2c_device_id cm36651_id[] = {
	{ "cm36651", 0 },
	{ }
};

MODULE_DEVICE_TABLE(i2c, cm36651_id);

static const struct of_device_id cm36651_of_match[] = {
	{ .compatible = "capella,cm36651" },
	{ }
};

static struct i2c_driver cm36651_driver = {
	.driver = {
		.name	= "cm36651",
		.of_match_table = cm36651_of_match,
		.owner	= THIS_MODULE,
	},
	.probe		= cm36651_probe,
	.remove		= cm36651_remove,
	.id_table	= cm36651_id,
};

module_i2c_driver(cm36651_driver);

MODULE_AUTHOR("Beomho Seo <beomho.seo@samsung.com>");
MODULE_DESCRIPTION("CM36651 proximity/ambient light sensor driver");
MODULE_LICENSE("GPL v2");