Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 907 insertions, 0 deletions

diff --git a/drivers/iio/light/veml6030.c b/drivers/iio/light/veml6030.c
new file mode 100644
index 000000000..de85c9b30
--- /dev/null
+++ b/drivers/iio/light/veml6030.c
@@ -0,0 +1,907 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * VEML6030 Ambient Light Sensor
+ *
+ * Copyright (c) 2019, Rishi Gupta <gupt21@gmail.com>
+ *
+ * Datasheet: https://www.vishay.com/docs/84366/veml6030.pdf
+ * Appnote-84367: https://www.vishay.com/docs/84367/designingveml6030.pdf
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/regmap.h>
+#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+
+/* Device registers */
+#define VEML6030_REG_ALS_CONF   0x00
+#define VEML6030_REG_ALS_WH     0x01
+#define VEML6030_REG_ALS_WL     0x02
+#define VEML6030_REG_ALS_PSM    0x03
+#define VEML6030_REG_ALS_DATA   0x04
+#define VEML6030_REG_WH_DATA    0x05
+#define VEML6030_REG_ALS_INT    0x06
+
+/* Bit masks for specific functionality */
+#define VEML6030_ALS_IT       GENMASK(9, 6)
+#define VEML6030_PSM          GENMASK(2, 1)
+#define VEML6030_ALS_PERS     GENMASK(5, 4)
+#define VEML6030_ALS_GAIN     GENMASK(12, 11)
+#define VEML6030_PSM_EN       BIT(0)
+#define VEML6030_INT_TH_LOW   BIT(15)
+#define VEML6030_INT_TH_HIGH  BIT(14)
+#define VEML6030_ALS_INT_EN   BIT(1)
+#define VEML6030_ALS_SD       BIT(0)
+
+/*
+ * The resolution depends on both gain and integration time. The
+ * cur_resolution stores one of the resolution mentioned in the
+ * table during startup and gets updated whenever integration time
+ * or gain is changed.
+ *
+ * Table 'resolution and maximum detection range' in appnote 84367
+ * is visualized as a 2D array. The cur_gain stores index of gain
+ * in this table (0-3) while the cur_integration_time holds index
+ * of integration time (0-5).
+ */
+struct veml6030_data {
+	struct i2c_client *client;
+	struct regmap *regmap;
+	int cur_resolution;
+	int cur_gain;
+	int cur_integration_time;
+};
+
+/* Integration time available in seconds */
+static IIO_CONST_ATTR(in_illuminance_integration_time_available,
+				"0.025 0.05 0.1 0.2 0.4 0.8");
+
+/*
+ * Scale is 1/gain. Value 0.125 is ALS gain x (1/8), 0.25 is
+ * ALS gain x (1/4), 1.0 = ALS gain x 1 and 2.0 is ALS gain x 2.
+ */
+static IIO_CONST_ATTR(in_illuminance_scale_available,
+				"0.125 0.25 1.0 2.0");
+
+static struct attribute *veml6030_attributes[] = {
+	&iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr,
+	&iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group veml6030_attr_group = {
+	.attrs = veml6030_attributes,
+};
+
+/*
+ * Persistence = 1/2/4/8 x integration time
+ * Minimum time for which light readings must stay above configured
+ * threshold to assert the interrupt.
+ */
+static const char * const period_values[] = {
+		"0.1 0.2 0.4 0.8",
+		"0.2 0.4 0.8 1.6",
+		"0.4 0.8 1.6 3.2",
+		"0.8 1.6 3.2 6.4",
+		"0.05 0.1 0.2 0.4",
+		"0.025 0.050 0.1 0.2"
+};
+
+/*
+ * Return list of valid period values in seconds corresponding to
+ * the currently active integration time.
+ */
+static ssize_t in_illuminance_period_available_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	int ret, reg, x;
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't read als conf register %d\n", ret);
+		return ret;
+	}
+
+	ret = ((reg >> 6) & 0xF);
+	switch (ret) {
+	case 0:
+	case 1:
+	case 2:
+	case 3:
+		x = ret;
+		break;
+	case 8:
+		x = 4;
+		break;
+	case 12:
+		x = 5;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", period_values[x]);
+}
+
+static IIO_DEVICE_ATTR_RO(in_illuminance_period_available, 0);
+
+static struct attribute *veml6030_event_attributes[] = {
+	&iio_dev_attr_in_illuminance_period_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group veml6030_event_attr_group = {
+	.attrs = veml6030_event_attributes,
+};
+
+static int veml6030_als_pwr_on(struct veml6030_data *data)
+{
+	return regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+				 VEML6030_ALS_SD, 0);
+}
+
+static int veml6030_als_shut_down(struct veml6030_data *data)
+{
+	return regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+				 VEML6030_ALS_SD, 1);
+}
+
+static void veml6030_als_shut_down_action(void *data)
+{
+	veml6030_als_shut_down(data);
+}
+
+static const struct iio_event_spec veml6030_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) |
+		BIT(IIO_EV_INFO_ENABLE),
+	},
+};
+
+/* Channel number */
+enum veml6030_chan {
+	CH_ALS,
+	CH_WHITE,
+};
+
+static const struct iio_chan_spec veml6030_channels[] = {
+	{
+		.type = IIO_LIGHT,
+		.channel = CH_ALS,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				BIT(IIO_CHAN_INFO_PROCESSED) |
+				BIT(IIO_CHAN_INFO_INT_TIME) |
+				BIT(IIO_CHAN_INFO_SCALE),
+		.event_spec = veml6030_event_spec,
+		.num_event_specs = ARRAY_SIZE(veml6030_event_spec),
+	},
+	{
+		.type = IIO_INTENSITY,
+		.channel = CH_WHITE,
+		.modified = 1,
+		.channel2 = IIO_MOD_LIGHT_BOTH,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				BIT(IIO_CHAN_INFO_PROCESSED),
+	},
+};
+
+static const struct regmap_config veml6030_regmap_config = {
+	.name = "veml6030_regmap",
+	.reg_bits = 8,
+	.val_bits = 16,
+	.max_register = VEML6030_REG_ALS_INT,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+static int veml6030_get_intgrn_tm(struct iio_dev *indio_dev,
+						int *val, int *val2)
+{
+	int ret, reg;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't read als conf register %d\n", ret);
+		return ret;
+	}
+
+	switch ((reg >> 6) & 0xF) {
+	case 0:
+		*val2 = 100000;
+		break;
+	case 1:
+		*val2 = 200000;
+		break;
+	case 2:
+		*val2 = 400000;
+		break;
+	case 3:
+		*val2 = 800000;
+		break;
+	case 8:
+		*val2 = 50000;
+		break;
+	case 12:
+		*val2 = 25000;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	*val = 0;
+	return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int veml6030_set_intgrn_tm(struct iio_dev *indio_dev,
+						int val, int val2)
+{
+	int ret, new_int_time, int_idx;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	if (val)
+		return -EINVAL;
+
+	switch (val2) {
+	case 25000:
+		new_int_time = 0x300;
+		int_idx = 5;
+		break;
+	case 50000:
+		new_int_time = 0x200;
+		int_idx = 4;
+		break;
+	case 100000:
+		new_int_time = 0x00;
+		int_idx = 3;
+		break;
+	case 200000:
+		new_int_time = 0x40;
+		int_idx = 2;
+		break;
+	case 400000:
+		new_int_time = 0x80;
+		int_idx = 1;
+		break;
+	case 800000:
+		new_int_time = 0xC0;
+		int_idx = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+					VEML6030_ALS_IT, new_int_time);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't update als integration time %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * Cache current integration time and update resolution. For every
+	 * increase in integration time to next level, resolution is halved
+	 * and vice-versa.
+	 */
+	if (data->cur_integration_time < int_idx)
+		data->cur_resolution <<= int_idx - data->cur_integration_time;
+	else if (data->cur_integration_time > int_idx)
+		data->cur_resolution >>= data->cur_integration_time - int_idx;
+
+	data->cur_integration_time = int_idx;
+
+	return ret;
+}
+
+static int veml6030_read_persistence(struct iio_dev *indio_dev,
+						int *val, int *val2)
+{
+	int ret, reg, period, x, y;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = veml6030_get_intgrn_tm(indio_dev, &x, &y);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't read als conf register %d\n", ret);
+	}
+
+	/* integration time multiplied by 1/2/4/8 */
+	period = y * (1 << ((reg >> 4) & 0x03));
+
+	*val = period / 1000000;
+	*val2 = period % 1000000;
+
+	return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int veml6030_write_persistence(struct iio_dev *indio_dev,
+						int val, int val2)
+{
+	int ret, period, x, y;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = veml6030_get_intgrn_tm(indio_dev, &x, &y);
+	if (ret < 0)
+		return ret;
+
+	if (!val) {
+		period = val2 / y;
+	} else {
+		if ((val == 1) && (val2 == 600000))
+			period = 1600000 / y;
+		else if ((val == 3) && (val2 == 200000))
+			period = 3200000 / y;
+		else if ((val == 6) && (val2 == 400000))
+			period = 6400000 / y;
+		else
+			period = -1;
+	}
+
+	if (period <= 0 || period > 8 || hweight8(period) != 1)
+		return -EINVAL;
+
+	ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+				VEML6030_ALS_PERS, (ffs(period) - 1) << 4);
+	if (ret)
+		dev_err(&data->client->dev,
+				"can't set persistence value %d\n", ret);
+
+	return ret;
+}
+
+static int veml6030_set_als_gain(struct iio_dev *indio_dev,
+						int val, int val2)
+{
+	int ret, new_gain, gain_idx;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	if (val == 0 && val2 == 125000) {
+		new_gain = 0x1000; /* 0x02 << 11 */
+		gain_idx = 3;
+	} else if (val == 0 && val2 == 250000) {
+		new_gain = 0x1800;
+		gain_idx = 2;
+	} else if (val == 1 && val2 == 0) {
+		new_gain = 0x00;
+		gain_idx = 1;
+	} else if (val == 2 && val2 == 0) {
+		new_gain = 0x800;
+		gain_idx = 0;
+	} else {
+		return -EINVAL;
+	}
+
+	ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+					VEML6030_ALS_GAIN, new_gain);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't set als gain %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * Cache currently set gain & update resolution. For every
+	 * increase in the gain to next level, resolution is halved
+	 * and vice-versa.
+	 */
+	if (data->cur_gain < gain_idx)
+		data->cur_resolution <<= gain_idx - data->cur_gain;
+	else if (data->cur_gain > gain_idx)
+		data->cur_resolution >>= data->cur_gain - gain_idx;
+
+	data->cur_gain = gain_idx;
+
+	return ret;
+}
+
+static int veml6030_get_als_gain(struct iio_dev *indio_dev,
+						int *val, int *val2)
+{
+	int ret, reg;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't read als conf register %d\n", ret);
+		return ret;
+	}
+
+	switch ((reg >> 11) & 0x03) {
+	case 0:
+		*val = 1;
+		*val2 = 0;
+		break;
+	case 1:
+		*val = 2;
+		*val2 = 0;
+		break;
+	case 2:
+		*val = 0;
+		*val2 = 125000;
+		break;
+	case 3:
+		*val = 0;
+		*val2 = 250000;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int veml6030_read_thresh(struct iio_dev *indio_dev,
+						int *val, int *val2, int dir)
+{
+	int ret, reg;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	if (dir == IIO_EV_DIR_RISING)
+		ret = regmap_read(data->regmap, VEML6030_REG_ALS_WH, &reg);
+	else
+		ret = regmap_read(data->regmap, VEML6030_REG_ALS_WL, &reg);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't read als threshold value %d\n", ret);
+		return ret;
+	}
+
+	*val = reg & 0xffff;
+	return IIO_VAL_INT;
+}
+
+static int veml6030_write_thresh(struct iio_dev *indio_dev,
+						int val, int val2, int dir)
+{
+	int ret;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	if (val > 0xFFFF || val < 0 || val2)
+		return -EINVAL;
+
+	if (dir == IIO_EV_DIR_RISING) {
+		ret = regmap_write(data->regmap, VEML6030_REG_ALS_WH, val);
+		if (ret)
+			dev_err(&data->client->dev,
+					"can't set high threshold %d\n", ret);
+	} else {
+		ret = regmap_write(data->regmap, VEML6030_REG_ALS_WL, val);
+		if (ret)
+			dev_err(&data->client->dev,
+					"can't set low threshold %d\n", ret);
+	}
+
+	return ret;
+}
+
+/*
+ * Provide both raw as well as light reading in lux.
+ * light (in lux) = resolution * raw reading
+ */
+static int veml6030_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan, int *val,
+			    int *val2, long mask)
+{
+	int ret, reg;
+	struct veml6030_data *data = iio_priv(indio_dev);
+	struct regmap *regmap = data->regmap;
+	struct device *dev = &data->client->dev;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+	case IIO_CHAN_INFO_PROCESSED:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			ret = regmap_read(regmap, VEML6030_REG_ALS_DATA, &reg);
+			if (ret < 0) {
+				dev_err(dev, "can't read als data %d\n", ret);
+				return ret;
+			}
+			if (mask == IIO_CHAN_INFO_PROCESSED) {
+				*val = (reg * data->cur_resolution) / 10000;
+				*val2 = (reg * data->cur_resolution) % 10000;
+				return IIO_VAL_INT_PLUS_MICRO;
+			}
+			*val = reg;
+			return IIO_VAL_INT;
+		case IIO_INTENSITY:
+			ret = regmap_read(regmap, VEML6030_REG_WH_DATA, &reg);
+			if (ret < 0) {
+				dev_err(dev, "can't read white data %d\n", ret);
+				return ret;
+			}
+			if (mask == IIO_CHAN_INFO_PROCESSED) {
+				*val = (reg * data->cur_resolution) / 10000;
+				*val2 = (reg * data->cur_resolution) % 10000;
+				return IIO_VAL_INT_PLUS_MICRO;
+			}
+			*val = reg;
+			return IIO_VAL_INT;
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_INT_TIME:
+		if (chan->type == IIO_LIGHT)
+			return veml6030_get_intgrn_tm(indio_dev, val, val2);
+		return -EINVAL;
+	case IIO_CHAN_INFO_SCALE:
+		if (chan->type == IIO_LIGHT)
+			return veml6030_get_als_gain(indio_dev, val, val2);
+		return -EINVAL;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6030_write_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan,
+				int val, int val2, long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_INT_TIME:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			return veml6030_set_intgrn_tm(indio_dev, val, val2);
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			return veml6030_set_als_gain(indio_dev, val, val2);
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6030_read_event_val(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)
+{
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+		case IIO_EV_DIR_FALLING:
+			return veml6030_read_thresh(indio_dev, val, val2, dir);
+		default:
+			return -EINVAL;
+		}
+		break;
+	case IIO_EV_INFO_PERIOD:
+		return veml6030_read_persistence(indio_dev, val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6030_write_event_val(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)
+{
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		return veml6030_write_thresh(indio_dev, val, val2, dir);
+	case IIO_EV_INFO_PERIOD:
+		return veml6030_write_persistence(indio_dev, val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6030_read_interrupt_config(struct iio_dev *indio_dev,
+		const struct iio_chan_spec *chan, enum iio_event_type type,
+		enum iio_event_direction dir)
+{
+	int ret, reg;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, &reg);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't read als conf register %d\n", ret);
+		return ret;
+	}
+
+	if (reg & VEML6030_ALS_INT_EN)
+		return 1;
+	else
+		return 0;
+}
+
+/*
+ * Sensor should not be measuring light when interrupt is configured.
+ * Therefore correct sequence to configure interrupt functionality is:
+ * shut down -> enable/disable interrupt -> power on
+ *
+ * state = 1 enables interrupt, state = 0 disables interrupt
+ */
+static int veml6030_write_interrupt_config(struct iio_dev *indio_dev,
+		const struct iio_chan_spec *chan, enum iio_event_type type,
+		enum iio_event_direction dir, int state)
+{
+	int ret;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	if (state < 0 || state > 1)
+		return -EINVAL;
+
+	ret = veml6030_als_shut_down(data);
+	if (ret < 0) {
+		dev_err(&data->client->dev,
+			"can't disable als to configure interrupt %d\n", ret);
+		return ret;
+	}
+
+	/* enable interrupt + power on */
+	ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF,
+			VEML6030_ALS_INT_EN | VEML6030_ALS_SD, state << 1);
+	if (ret)
+		dev_err(&data->client->dev,
+			"can't enable interrupt & poweron als %d\n", ret);
+
+	return ret;
+}
+
+static const struct iio_info veml6030_info = {
+	.read_raw  = veml6030_read_raw,
+	.write_raw = veml6030_write_raw,
+	.read_event_value = veml6030_read_event_val,
+	.write_event_value	= veml6030_write_event_val,
+	.read_event_config = veml6030_read_interrupt_config,
+	.write_event_config	= veml6030_write_interrupt_config,
+	.attrs = &veml6030_attr_group,
+	.event_attrs = &veml6030_event_attr_group,
+};
+
+static const struct iio_info veml6030_info_no_irq = {
+	.read_raw  = veml6030_read_raw,
+	.write_raw = veml6030_write_raw,
+	.attrs = &veml6030_attr_group,
+};
+
+static irqreturn_t veml6030_event_handler(int irq, void *private)
+{
+	int ret, reg, evtdir;
+	struct iio_dev *indio_dev = private;
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = regmap_read(data->regmap, VEML6030_REG_ALS_INT, &reg);
+	if (ret) {
+		dev_err(&data->client->dev,
+				"can't read als interrupt register %d\n", ret);
+		return IRQ_HANDLED;
+	}
+
+	/* Spurious interrupt handling */
+	if (!(reg & (VEML6030_INT_TH_HIGH | VEML6030_INT_TH_LOW)))
+		return IRQ_NONE;
+
+	if (reg & VEML6030_INT_TH_HIGH)
+		evtdir = IIO_EV_DIR_RISING;
+	else
+		evtdir = IIO_EV_DIR_FALLING;
+
+	iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY,
+					0, IIO_EV_TYPE_THRESH, evtdir),
+					iio_get_time_ns(indio_dev));
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Set ALS gain to 1/8, integration time to 100 ms, PSM to mode 2,
+ * persistence to 1 x integration time and the threshold
+ * interrupt disabled by default. First shutdown the sensor,
+ * update registers and then power on the sensor.
+ */
+static int veml6030_hw_init(struct iio_dev *indio_dev)
+{
+	int ret, val;
+	struct veml6030_data *data = iio_priv(indio_dev);
+	struct i2c_client *client = data->client;
+
+	ret = veml6030_als_shut_down(data);
+	if (ret) {
+		dev_err(&client->dev, "can't shutdown als %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(data->regmap, VEML6030_REG_ALS_CONF, 0x1001);
+	if (ret) {
+		dev_err(&client->dev, "can't setup als configs %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_PSM,
+				 VEML6030_PSM | VEML6030_PSM_EN, 0x03);
+	if (ret) {
+		dev_err(&client->dev, "can't setup default PSM %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(data->regmap, VEML6030_REG_ALS_WH, 0xFFFF);
+	if (ret) {
+		dev_err(&client->dev, "can't setup high threshold %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(data->regmap, VEML6030_REG_ALS_WL, 0x0000);
+	if (ret) {
+		dev_err(&client->dev, "can't setup low threshold %d\n", ret);
+		return ret;
+	}
+
+	ret = veml6030_als_pwr_on(data);
+	if (ret) {
+		dev_err(&client->dev, "can't poweron als %d\n", ret);
+		return ret;
+	}
+
+	/* Wait 4 ms to let processor & oscillator start correctly */
+	usleep_range(4000, 4002);
+
+	/* Clear stale interrupt status bits if any during start */
+	ret = regmap_read(data->regmap, VEML6030_REG_ALS_INT, &val);
+	if (ret < 0) {
+		dev_err(&client->dev,
+			"can't clear als interrupt status %d\n", ret);
+		return ret;
+	}
+
+	/* Cache currently active measurement parameters */
+	data->cur_gain = 3;
+	data->cur_resolution = 4608;
+	data->cur_integration_time = 3;
+
+	return ret;
+}
+
+static int veml6030_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	int ret;
+	struct veml6030_data *data;
+	struct iio_dev *indio_dev;
+	struct regmap *regmap;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "i2c adapter doesn't support plain i2c\n");
+		return -EOPNOTSUPP;
+	}
+
+	regmap = devm_regmap_init_i2c(client, &veml6030_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "can't setup regmap\n");
+		return PTR_ERR(regmap);
+	}
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	data->client = client;
+	data->regmap = regmap;
+
+	indio_dev->name = "veml6030";
+	indio_dev->channels = veml6030_channels;
+	indio_dev->num_channels = ARRAY_SIZE(veml6030_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	if (client->irq) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+						NULL, veml6030_event_handler,
+						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						"veml6030", indio_dev);
+		if (ret < 0) {
+			dev_err(&client->dev,
+					"irq %d request failed\n", client->irq);
+			return ret;
+		}
+		indio_dev->info = &veml6030_info;
+	} else {
+		indio_dev->info = &veml6030_info_no_irq;
+	}
+
+	ret = veml6030_hw_init(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	ret = devm_add_action_or_reset(&client->dev,
+					veml6030_als_shut_down_action, data);
+	if (ret < 0)
+		return ret;
+
+	return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static int __maybe_unused veml6030_runtime_suspend(struct device *dev)
+{
+	int ret;
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = veml6030_als_shut_down(data);
+	if (ret < 0)
+		dev_err(&data->client->dev, "can't suspend als %d\n", ret);
+
+	return ret;
+}
+
+static int __maybe_unused veml6030_runtime_resume(struct device *dev)
+{
+	int ret;
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct veml6030_data *data = iio_priv(indio_dev);
+
+	ret = veml6030_als_pwr_on(data);
+	if (ret < 0)
+		dev_err(&data->client->dev, "can't resume als %d\n", ret);
+
+	return ret;
+}
+
+static const struct dev_pm_ops veml6030_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
+	SET_RUNTIME_PM_OPS(veml6030_runtime_suspend,
+				veml6030_runtime_resume, NULL)
+};
+
+static const struct of_device_id veml6030_of_match[] = {
+	{ .compatible = "vishay,veml6030" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, veml6030_of_match);
+
+static const struct i2c_device_id veml6030_id[] = {
+	{ "veml6030", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, veml6030_id);
+
+static struct i2c_driver veml6030_driver = {
+	.driver = {
+		.name = "veml6030",
+		.of_match_table = veml6030_of_match,
+		.pm = &veml6030_pm_ops,
+	},
+	.probe = veml6030_probe,
+	.id_table = veml6030_id,
+};
+module_i2c_driver(veml6030_driver);
+
+MODULE_AUTHOR("Rishi Gupta <gupt21@gmail.com>");
+MODULE_DESCRIPTION("VEML6030 Ambient Light Sensor");
+MODULE_LICENSE("GPL v2");