[PATCH v2 1/2] iio: light: Add support for vishay vcnl4035

[Parthiban Nallathambi <pn@denx.de>]

Add support for VCNL4035, which is capable of Ambient light
sensing (ALS) and proximity function. This patch adds support
only for ALS function

Signed-off-by: Parthiban Nallathambi <pn@denx.de>
---

Changelog since v1:

1. Fixed 0-day warning on le16_to_cpu usage
2. Persistence value is directly mapped to datasheet's value to
avoid confusions of usage from sysfs
---
 drivers/iio/light/Kconfig    |  12 +
 drivers/iio/light/Makefile   |   1 +
 drivers/iio/light/vcnl4035.c | 682 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 695 insertions(+)
 create mode 100644 drivers/iio/light/vcnl4035.c

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index c7ef8d1862d6..b7069a4c28a2 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -447,6 +447,18 @@ config VCNL4000
 	 To compile this driver as a module, choose M here: the
 	 module will be called vcnl4000.
 
+config VCNL4035
+	tristate "VCNL4035 combined ALS and proximity sensor"
+	select REGMAP_I2C
+	depends on I2C
+	help
+	 Say Y here if you want to build a driver for the Vishay VCNL4035,
+	 combined ambient light (ALS) and proximity sensor. Currently only ALS
+	 function is available.
+
+	 To compile this driver as a module, choose M here: the
+	 module will be called vcnl4035.
+
 config VEML6070
 	tristate "VEML6070 UV A light sensor"
 	depends on I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index 80943af5d627..dce98511a59b 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_TSL2772)		+= tsl2772.o
 obj-$(CONFIG_TSL4531)		+= tsl4531.o
 obj-$(CONFIG_US5182D)		+= us5182d.o
 obj-$(CONFIG_VCNL4000)		+= vcnl4000.o
+obj-$(CONFIG_VCNL4035)		+= vcnl4035.o
 obj-$(CONFIG_VEML6070)		+= veml6070.o
 obj-$(CONFIG_VL6180)		+= vl6180.o
 obj-$(CONFIG_ZOPT2201)		+= zopt2201.o
diff --git a/drivers/iio/light/vcnl4035.c b/drivers/iio/light/vcnl4035.c
new file mode 100644
index 000000000000..45eccb462ed0
--- /dev/null
+++ b/drivers/iio/light/vcnl4035.c
@@ -0,0 +1,682 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * VCNL4035 Ambient Light and Proximity Sensor - 7-bit I2C slave address 0x60
+ *
+ * Copyright (c) 2018, DENX Software Engineering GmbH
+ * Author: Parthiban Nallathambi <pn@denx.de>
+ *
+ *
+ * TODO: Proximity
+ */
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define VCNL4035_DRV_NAME	"vcnl4035"
+#define VCNL4035_IRQ_NAME	"vcnl4035_event"
+#define VCNL4035_REGMAP_NAME	"vcnl4035_regmap"
+
+/* Device registers */
+#define VCNL4035_ALS_CONF	0x00
+#define VCNL4035_ALS_THDH	0x01
+#define VCNL4035_ALS_THDL	0x02
+#define VCNL4035_ALS_DATA	0x0B
+#define	VCNL4035_INT_FLAG	0x0D
+#define VCNL4035_DEV_ID		0x0E
+
+/* Register masks */
+#define VCNL4035_MODE_ALS_MASK		BIT(0)
+#define VCNL4035_MODE_ALS_INT_MASK	BIT(1)
+#define VCNL4035_ALS_IT_MASK		GENMASK(7, 5)
+#define VCNL4035_ALS_PERS_MASK		GENMASK(3, 2)
+#define VCNL4035_INT_ALS_IF_H_MASK	BIT(12)
+#define VCNL4035_INT_ALS_IF_L_MASK	BIT(13)
+
+/* Default values */
+#define VCNL4035_MODE_ALS_ENABLE	BIT(0)
+#define VCNL4035_MODE_ALS_DISABLE	0x00
+#define VCNL4035_MODE_ALS_INT_ENABLE	BIT(1)
+#define VCNL4035_MODE_ALS_INT_DISABLE	0x00
+#define VCNL4035_DEV_ID_VAL		0x80
+#define VCNL4035_ALS_IT_DEFAULT		0x01
+#define VCNL4035_ALS_PERS_DEFAULT	0x00
+#define VCNL4035_ALS_THDH_DEFAULT	5000
+#define VCNL4035_ALS_THDL_DEFAULT	100
+#define VCNL4035_SLEEP_DELAY_MS		2000
+
+struct vcnl4035_data {
+	struct i2c_client *client;
+	struct regmap *regmap;
+	/* protect device settings persistence, integration time, threshold */
+	struct mutex lock;
+	unsigned int als_it_val;
+	unsigned int als_persistence:4;
+	unsigned int als_thresh_low;
+	unsigned int als_thresh_high;
+	struct iio_trigger *drdy_trigger0;
+	s64 irq_timestamp;
+};
+
+static inline bool vcnl4035_is_triggered(struct vcnl4035_data *data)
+{
+	int ret;
+	int reg;
+
+	ret = regmap_read(data->regmap, VCNL4035_INT_FLAG, &reg);
+	if (ret < 0)
+		return false;
+	if (reg & (VCNL4035_INT_ALS_IF_H_MASK | VCNL4035_INT_ALS_IF_L_MASK))
+		return true;
+	else
+		return false;
+}
+
+static irqreturn_t vcnl4035_drdy_irq_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct vcnl4035_data *data = iio_priv(indio_dev);
+
+	data->irq_timestamp = iio_get_time_ns(indio_dev);
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t vcnl4035_drdy_irq_thread(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct vcnl4035_data *data = iio_priv(indio_dev);
+
+	if (vcnl4035_is_triggered(data)) {
+		iio_trigger_poll_chained(data->drdy_trigger0);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+/* Triggered buffer */
+static irqreturn_t vcnl4035_trigger_consumer_store_time(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+
+	if (!iio_trigger_using_own(indio_dev))
+		pf->timestamp = iio_get_time_ns(indio_dev);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t vcnl4035_trigger_consumer_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct vcnl4035_data *data = iio_priv(indio_dev);
+	int als_data;
+	int ret;
+
+	if (iio_trigger_using_own(indio_dev) && data->irq_timestamp) {
+		pf->timestamp = data->irq_timestamp;
+		data->irq_timestamp = 0;
+	}
+
+	if (!pf->timestamp)
+		pf->timestamp = iio_get_time_ns(indio_dev);
+
+	mutex_lock(&data->lock);
+	ret = regmap_read(data->regmap, VCNL4035_ALS_DATA, &als_data);
+	mutex_unlock(&data->lock);
+	if (!ret)
+		iio_push_to_buffers_with_timestamp(indio_dev,
+						   &als_data,
+						   pf->timestamp);
+	else
+		dev_err(&data->client->dev,
+			"Trigger consumer can't read from sensor.\n");
+	pf->timestamp = 0;
+
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int vcnl4035_als_drdy_set_state(struct iio_trigger *trigger,
+					bool enable_drdy)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trigger);
+	struct vcnl4035_data *data = iio_priv(indio_dev);
+	int val = enable_drdy ? VCNL4035_MODE_ALS_INT_ENABLE :
+					VCNL4035_MODE_ALS_INT_DISABLE;
+	int ret;
+
+	ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
+				 VCNL4035_MODE_ALS_INT_MASK,
+				 val);
+	if (ret)
+		dev_err(&data->client->dev, "%s failed\n", __func__);
+
+	return ret;
+}
+
+static const struct iio_trigger_ops vcnl4035_trigger_ops = {
+	.set_trigger_state = vcnl4035_als_drdy_set_state,
+};
+
+/*
+ *	Device IT	INT Time(ms)	Scale (lux/step)
+ *	000		50		0.064
+ *	001		100		0.032
+ *	010		200		0.016
+ *	100		400		0.008
+ *	101 - 111	800		0.004
+ * Values are proportial, so ALS INT is selected for input due to
+ * simplicity reason. Integration time value and scaling is
+ * calculated based on device INT value
+ *
+ * Raw value needs to be scaled using ALS STEPS
+ *
+ */
+static int vcnl4035_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan, int *val,
+			    int *val2, long mask)
+{
+	struct vcnl4035_data *data = iio_priv(indio_dev);
+	int ret;
+	int busy;
+	int raw_data;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		busy = iio_device_claim_direct_mode(indio_dev);
+		if (busy)
+			return -EBUSY;
+
+		ret = regmap_read(data->regmap, VCNL4035_ALS_DATA, &raw_data);
+		iio_device_release_direct_mode(indio_dev);
+		if (ret < 0)
+			return ret;
+
+		*val = raw_data;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_INT_TIME:
+		mutex_lock(&data->lock);
+		*val = data->als_it_val * 100;
+		if (!*val)
+			*val = 50;
+		mutex_unlock(&data->lock);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		mutex_lock(&data->lock);
+		*val = 64;
+		if (!data->als_it_val)
+			*val2 = 1000;
+		else
+			*val2 = data->als_it_val * 2 * 1000;
+		mutex_unlock(&data->lock);
+		return IIO_VAL_FRACTIONAL;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int vcnl4035_write_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan,
+				int val, int val2, long mask)
+{
+	int ret;
+	struct vcnl4035_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_INT_TIME:
+		if (val <= 0 || val > 800)
+			return -EINVAL;
+		mutex_lock(&data->lock);
+		ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
+					 VCNL4035_ALS_IT_MASK,
+					 val / 100);
+		if (!ret)
+			data->als_it_val = val / 100;
+		mutex_unlock(&data->lock);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return ret;
+}
+
+/* No direct ABI for persistence and threshold, so eventing */
+static int vcnl4035_read_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 vcnl4035_data *data = iio_priv(indio_dev);
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			mutex_lock(&data->lock);
+			*val = data->als_thresh_high;
+			mutex_unlock(&data->lock);
+			break;
+		case IIO_EV_DIR_FALLING:
+			mutex_lock(&data->lock);
+			*val = data->als_thresh_low;
+			mutex_unlock(&data->lock);
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	case IIO_EV_INFO_PERIOD:
+		mutex_lock(&data->lock);
+		*val = data->als_persistence;
+		mutex_unlock(&data->lock);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return IIO_VAL_INT;
+}
+
+static int vcnl4035_write_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 vcnl4035_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		/* 16 bit threshold range */
+		if (val < 0 || val > 65535)
+			return -EINVAL;
+		if (dir == IIO_EV_DIR_RISING) {
+			if (val < data->als_thresh_low)
+				return -EINVAL;
+			mutex_lock(&data->lock);
+			ret = regmap_write(data->regmap, VCNL4035_ALS_THDH,
+					   val);
+			mutex_unlock(&data->lock);
+			if (ret)
+				return ret;
+			data->als_thresh_high = val;
+		} else {
+			if (val > data->als_thresh_high)
+				return -EINVAL;
+			mutex_lock(&data->lock);
+			ret = regmap_write(data->regmap, VCNL4035_ALS_THDL,
+					   val);
+			mutex_unlock(&data->lock);
+			if (ret)
+				return ret;
+			data->als_thresh_low = val;
+		}
+		break;
+	case IIO_EV_INFO_PERIOD:
+		/* allow only 1 2 4 8 as persistence value */
+		if (val < 0 || val > 8 || (__sw_hweight8(val) != 1))
+			return -EINVAL;
+		mutex_lock(&data->lock);
+		ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
+					 VCNL4035_ALS_PERS_MASK, val);
+		mutex_unlock(&data->lock);
+		if (ret)
+			return ret;
+		data->als_persistence = val;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static IIO_CONST_ATTR(als_available_integration_time, "50 100 200 400 800");
+static IIO_CONST_ATTR(als_available_persistence, "1 2 4 8");
+static IIO_CONST_ATTR(als_available_threshold_range, "0 65535");
+
+static struct attribute *vcnl4035_attributes[] = {
+	&iio_const_attr_als_available_integration_time.dev_attr.attr,
+	&iio_const_attr_als_available_threshold_range.dev_attr.attr,
+	&iio_const_attr_als_available_persistence.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group vcnl4035_attribute_group = {
+	.attrs = vcnl4035_attributes,
+};
+
+static const struct iio_info vcnl4035_info = {
+	.read_raw		= vcnl4035_read_raw,
+	.write_raw		= vcnl4035_write_raw,
+	.read_event_value	= vcnl4035_read_thresh,
+	.write_event_value	= vcnl4035_write_thresh,
+	.attrs			= &vcnl4035_attribute_group,
+};
+
+enum vcnl4035_scan_index_order {
+	VCNL4035_CHAN_INDEX_LIGHT,
+};
+
+static const unsigned long vcnl4035_available_scan_masks[] = {
+	BIT(VCNL4035_CHAN_INDEX_LIGHT), 0
+};
+
+static const struct iio_event_spec vcnl4035_event_spec[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE),
+	}, {
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_FALLING,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE),
+	}, {
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_EITHER,
+		.mask_separate = BIT(IIO_EV_INFO_PERIOD),
+	},
+};
+
+static const struct iio_chan_spec vcnl4035_channels[] = {
+	{
+		.type = IIO_INTENSITY,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				BIT(IIO_CHAN_INFO_INT_TIME) |
+				BIT(IIO_CHAN_INFO_SCALE),
+		.event_spec = vcnl4035_event_spec,
+		.num_event_specs = ARRAY_SIZE(vcnl4035_event_spec),
+		.scan_index = VCNL4035_CHAN_INDEX_LIGHT,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_LE,
+		},
+	},
+};
+
+static int vcnl4035_set_als_power_state(struct vcnl4035_data *data, u8 status)
+{
+	return regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
+					VCNL4035_MODE_ALS_MASK,
+					status);
+}
+
+static int vcnl4035_init(struct vcnl4035_data *data)
+{
+	int ret;
+	int id;
+
+	ret = regmap_read(data->regmap, VCNL4035_DEV_ID, &id);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Failed to read DEV_ID register\n");
+		return ret;
+	}
+
+	if (id != VCNL4035_DEV_ID_VAL) {
+		dev_err(&data->client->dev, "Wrong id, got %x, expected %x\n",
+			id, VCNL4035_DEV_ID_VAL);
+		return -ENODEV;
+	}
+
+#ifndef CONFIG_PM
+	ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_ENABLE);
+	if (ret < 0)
+		return ret;
+#endif
+	/* set default integration time - 100 ms for ALS */
+	ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
+				 VCNL4035_ALS_IT_MASK,
+				 VCNL4035_ALS_IT_DEFAULT);
+	if (ret) {
+		pr_err("regmap_update_bits default ALS IT returned %d\n", ret);
+		return ret;
+	}
+	data->als_it_val = VCNL4035_ALS_IT_DEFAULT;
+
+	/* set default persistence time - 1 for ALS */
+	ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
+				 VCNL4035_ALS_PERS_MASK,
+				 VCNL4035_ALS_PERS_DEFAULT);
+	if (ret) {
+		pr_err("regmap_update_bits default PERS returned %d\n", ret);
+		return ret;
+	}
+	data->als_persistence = VCNL4035_ALS_PERS_DEFAULT;
+
+	/* set default HIGH threshold for ALS */
+	ret = regmap_write(data->regmap, VCNL4035_ALS_THDH,
+				VCNL4035_ALS_THDH_DEFAULT);
+	if (ret) {
+		pr_err("regmap_write default THDH returned %d\n", ret);
+		return ret;
+	}
+	data->als_thresh_high = VCNL4035_ALS_THDH_DEFAULT;
+
+	/* set default LOW threshold for ALS */
+	ret = regmap_write(data->regmap, VCNL4035_ALS_THDL,
+				VCNL4035_ALS_THDL_DEFAULT);
+	if (ret) {
+		pr_err("regmap_write default THDL returned %d\n", ret);
+		return ret;
+	}
+	data->als_thresh_low = VCNL4035_ALS_THDL_DEFAULT;
+
+	return 0;
+}
+
+static bool vcnl4035_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case VCNL4035_ALS_CONF:
+	case VCNL4035_DEV_ID:
+		return false;
+	default:
+		return true;
+	}
+}
+
+static const struct regmap_config vcnl4035_regmap_config = {
+	.name		= VCNL4035_REGMAP_NAME,
+	.reg_bits	= 8,
+	.val_bits	= 16,
+	.max_register	= VCNL4035_DEV_ID,
+	.cache_type	= REGCACHE_RBTREE,
+	.volatile_reg	= vcnl4035_is_volatile_reg,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+static int vcnl4035_probe(struct i2c_client *client,
+				const struct i2c_device_id *id)
+{
+	struct vcnl4035_data *data;
+	struct iio_dev *indio_dev;
+	struct regmap *regmap;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	regmap = devm_regmap_init_i2c(client, &vcnl4035_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "regmap_init failed!\n");
+		return PTR_ERR(regmap);
+	}
+
+	data = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	data->client = client;
+	data->regmap = regmap;
+	mutex_init(&data->lock);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &vcnl4035_info;
+	indio_dev->name = VCNL4035_DRV_NAME;
+	indio_dev->channels = vcnl4035_channels;
+	indio_dev->num_channels = ARRAY_SIZE(vcnl4035_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	ret = vcnl4035_init(data);
+	if (ret < 0) {
+		dev_err(&client->dev, "vcnl4035 chip init failed\n");
+		return ret;
+	}
+
+	ret = pm_runtime_set_active(&client->dev);
+	if (ret < 0)
+		goto fail_poweroff;
+
+	pm_runtime_enable(&client->dev);
+	pm_runtime_set_autosuspend_delay(&client->dev, VCNL4035_SLEEP_DELAY_MS);
+	pm_runtime_use_autosuspend(&client->dev);
+
+	if (client->irq) {
+		data->drdy_trigger0 = devm_iio_trigger_alloc(
+			indio_dev->dev.parent,
+			"%s-dev%d", indio_dev->name, indio_dev->id);
+		if (!data->drdy_trigger0) {
+			ret = -ENOMEM;
+			goto fail_pm_disable;
+		}
+		data->drdy_trigger0->dev.parent = indio_dev->dev.parent;
+		data->drdy_trigger0->ops = &vcnl4035_trigger_ops;
+		indio_dev->available_scan_masks = vcnl4035_available_scan_masks;
+		iio_trigger_set_drvdata(data->drdy_trigger0, indio_dev);
+
+		/* IRQ to trigger mapping */
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+			vcnl4035_drdy_irq_handler, vcnl4035_drdy_irq_thread,
+			IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+			VCNL4035_IRQ_NAME, indio_dev);
+		if (ret < 0) {
+			dev_err(&client->dev, "request irq %d for trigger0 failed\n",
+				client->irq);
+			goto fail_pm_disable;
+			}
+
+		ret = devm_iio_trigger_register(indio_dev->dev.parent,
+						data->drdy_trigger0);
+		if (ret) {
+			dev_err(&client->dev, "iio trigger register failed\n");
+			goto fail_pm_disable;
+		}
+
+		/* Trigger setup */
+		ret = devm_iio_triggered_buffer_setup(indio_dev->dev.parent,
+			indio_dev,
+			vcnl4035_trigger_consumer_store_time,
+			vcnl4035_trigger_consumer_handler,
+			NULL);
+		if (ret < 0) {
+			dev_err(&client->dev, "iio triggered buffer setup failed\n");
+			goto fail_pm_disable;
+		}
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto fail_pm_disable;
+	dev_info(&client->dev, "%s Ambient light/proximity sensor\n",
+						VCNL4035_DRV_NAME);
+	return 0;
+
+fail_pm_disable:
+	pm_runtime_disable(&client->dev);
+	pm_runtime_set_suspended(&client->dev);
+	pm_runtime_put_noidle(&client->dev);
+fail_poweroff:
+	return vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_DISABLE);
+}
+
+static int vcnl4035_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+
+	pm_runtime_disable(&client->dev);
+	pm_runtime_set_suspended(&client->dev);
+	pm_runtime_put_noidle(&client->dev);
+
+	return vcnl4035_set_als_power_state(iio_priv(indio_dev),
+					VCNL4035_MODE_ALS_DISABLE);
+}
+
+#ifdef CONFIG_PM
+static int vcnl4035_runtime_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct vcnl4035_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_DISABLE);
+	regcache_mark_dirty(data->regmap);
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int vcnl4035_runtime_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct vcnl4035_data *data = iio_priv(indio_dev);
+	int ret;
+
+	regcache_sync(data->regmap);
+	ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_ENABLE);
+	if (ret < 0)
+		return ret;
+	/* wait for 1 ALS integration cycle */
+	msleep(data->als_it_val * 100);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops vcnl4035_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
+	SET_RUNTIME_PM_OPS(vcnl4035_runtime_suspend,
+			   vcnl4035_runtime_resume, NULL)
+};
+
+static const struct of_device_id vcnl4035_of_match[] = {
+	{ .compatible = "vishay,vcnl4035", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, vcnl4035_of_match);
+
+static const struct i2c_device_id vcnl4035_id[] = {
+	{ "vcnl4035", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, vcnl4035_id);
+
+static struct i2c_driver vcnl4035_driver = {
+	.driver = {
+		.name   = VCNL4035_DRV_NAME,
+		.pm	= &vcnl4035_pm_ops,
+		.of_match_table = of_match_ptr(vcnl4035_of_match),
+	},
+	.probe  = vcnl4035_probe,
+	.remove	= vcnl4035_remove,
+	.id_table = vcnl4035_id,
+};
+
+module_i2c_driver(vcnl4035_driver);
+
+MODULE_AUTHOR("Parthiban Nallathambi <pn@denx.de>");
+MODULE_DESCRIPTION("VCNL4035 Ambient Light Sensor driver");
+MODULE_LICENSE("GPL v2");
-- 
2.14.4