[PATCH 2/2] iio: light: bh1730: Add bh1730 light sensor driver

[Alexandre Hamamdjian via B4 Relay <devnull+azkali.limited.gmail.com@kernel.org>]

From: CTCaer <ctcaer@gmail.com>

Add a driver for the ROHM BH1730FVC ambient light sensor. The device
is a 16-bit I2C digital sensor with separate visible and infrared
photodiodes, four selectable gains (1x/2x/64x/128x) and a programmable
integration time.

The driver exposes illuminance via IIO, performs runtime gain and
integration-time tracking to keep the ADC in range, and supports
optional als-vdd / als-vid regulators. Per-board lux calibration data
(integration cycles, lux multiplier, optical-window coefficients, and
gain sensitivity coefficients) can be supplied via device tree;
sensible defaults are used otherwise.

Signed-off-by: CTCaer <ctcaer@gmail.com>
Signed-off-by: Alexandre Hamamdjian <azkali.limited@gmail.com>
---
 drivers/iio/light/Kconfig  |   9 +
 drivers/iio/light/Makefile |   1 +
 drivers/iio/light/bh1730.c | 686 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 696 insertions(+)

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index eff33e456c70..3869060567dd 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -135,6 +135,15 @@ config AS73211
 	 This driver can also be built as a module.  If so, the module
 	 will be called as73211.
 
+config BH1730
+	tristate "ROHM BH1730 ambient light sensor"
+	depends on I2C
+	help
+	  Say Y here to build support for the ROHM BH1730 ambient light sensor.
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called bh1730.
+
 config BH1745
 	tristate "ROHM BH1745 colour sensor"
 	depends on I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index c0048e0d5ca8..27ef7906a02a 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_APDS9300)		+= apds9300.o
 obj-$(CONFIG_APDS9306)		+= apds9306.o
 obj-$(CONFIG_APDS9960)		+= apds9960.o
 obj-$(CONFIG_AS73211)		+= as73211.o
+obj-$(CONFIG_BH1730)		+= bh1730.o
 obj-$(CONFIG_BH1745)		+= bh1745.o
 obj-$(CONFIG_BH1750)		+= bh1750.o
 obj-$(CONFIG_BH1780)		+= bh1780.o
diff --git a/drivers/iio/light/bh1730.c b/drivers/iio/light/bh1730.c
new file mode 100644
index 000000000000..c93290ff5661
--- /dev/null
+++ b/drivers/iio/light/bh1730.c
@@ -0,0 +1,686 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ROHM BH1730 ambient light sensor driver
+ *
+ * Copyright (c) 2021 CTCaer <ctcaer@gmail.com>
+ *
+ * Based on previous iio BH1730FVC drivers from:
+ * Copyright (c) 2018 Google, Inc.
+ * Author: Pierre Bourdon <delroth@google.com>
+ *
+ * Copyright (C) 2012 Samsung Electronics. All rights reserved.
+ * Author: Won Huh <won.huh@samsung.com>
+ *
+ * Data sheets:
+ *  http://www.rohm.com/web/global/datasheet/BH1730FVC/bh1730fvc-e
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/time.h>
+#include <linux/regulator/consumer.h>
+
+#define BH1730_NAME	"bh1730fvc"
+
+#define BH1730_CMD_BIT BIT(7)
+
+#define BH1730_REG_CONTROL	0x00
+#define BH1730_REG_TIMING	0x01
+#define BH1730_REG_INTERRUPT	0x02
+#define BH1730_REG_THLLOW	0x03
+#define BH1730_REG_THLHIGH	0x04
+#define BH1730_REG_THHLOW	0x05
+#define BH1730_REG_THHHIGH	0x06
+#define BH1730_REG_GAIN		0x07
+#define BH1730_REG_ID		0x12
+#define BH1730_REG_DATA0LOW	0x14
+#define BH1730_REG_DATA0HIGH	0x15
+#define BH1730_REG_DATA1LOW	0x16
+#define BH1730_REG_DATA1HIGH	0x17
+
+#define BH1730_CONTROL_POWER		BIT(0)
+#define BH1730_CONTROL_ADC_EN		BIT(1)
+#define BH1730_CONTROL_DATA0_ONLY	BIT(2)
+#define BH1730_CONTROL_ONE_TIME		BIT(3)
+#define BH1730_CONTROL_ADC_VALID	BIT(4)
+#define BH1730_CONTROL_INTR		BIT(5)
+
+#define BH1730_INTERNAL_CLOCK_NS	2800
+/* BH1730_INTERNAL_CLOCK_MS * 714 */
+#define BH1730_ADC_CALC_DELAY_US	2000
+/* BH1730_INTERNAL_CLOCK_MS * 964 */
+#define BH1730_ITIME_TO_US		2700
+
+#define BH1730_DEFAULT_INTEG_CYCLE	38
+#define BH1730_DEFAULT_ITIME_MS		100
+
+#define BH1730_POWER_ON_DELAY_US	10000
+
+#define BH1730_MAX_MEASURED_LUX		100000
+
+enum bh1730_gain {
+	BH1730_GAIN_1X = 0,
+	BH1730_GAIN_2X,
+	BH1730_GAIN_64X,
+	BH1730_GAIN_128X,
+};
+#define BH1730_MAX_GAIN_MULTIPLIER 128
+
+struct gain_coeff_t {
+	u32 cl;
+	u32 fl;
+};
+
+struct opt_win_coeff_t {
+	u32 rc;
+	u32 cv;
+	u32 ci;
+};
+
+struct lux_cal_data_t {
+	struct gain_coeff_t *gain_coeff;
+	struct opt_win_coeff_t *opt_win_coeff;
+	u32 opt_win_coeff_count;
+	u32 itime_cycle;
+	u32 mul;
+};
+
+/*
+ * No optical window or optical window that has flat transmittance
+ * from visible light to infrared light.
+ */
+static struct opt_win_coeff_t def_lux_coeff[] = {
+	{  260, 1290, 2733 },
+	{  550,  795,  859 },
+	{ 1090,  510,  345 },
+	{ 2130,  276,  130 }
+};
+
+static struct gain_coeff_t def_gain_coeff[] = {
+	{ 3000,    -1 }, /* 1x */
+	{ 2000,  9800 }, /* 2x */
+	{   15, 60000 }, /* 64x */
+	{    0,  1300 }  /* 128x */
+};
+
+static struct lux_cal_data_t def_lux_data = {
+	.gain_coeff = def_gain_coeff,
+	.opt_win_coeff = def_lux_coeff,
+	.opt_win_coeff_count = ARRAY_SIZE(def_lux_coeff),
+	.itime_cycle = BH1730_DEFAULT_INTEG_CYCLE,
+	.mul = 1000
+};
+
+struct bh1730_data {
+	struct i2c_client *client;
+	struct lux_cal_data_t cal;
+	struct regulator *reg_vdd;
+	struct regulator *reg_vid;
+	enum bh1730_gain gain;
+	u32 itime_us;
+	u32 tmt_us;
+};
+
+static int bh1730_read_word(struct bh1730_data *bh1730, u8 reg)
+{
+	int ret = i2c_smbus_read_word_data(bh1730->client,
+					   BH1730_CMD_BIT | reg);
+	if (ret < 0)
+		dev_err(&bh1730->client->dev,
+			"i2c read failed error %d, register %01x\n",
+			ret, reg);
+
+	return ret;
+}
+
+static int bh1730_write(struct bh1730_data *bh1730, u8 reg, u8 val)
+{
+	int ret = i2c_smbus_write_byte_data(bh1730->client,
+					    BH1730_CMD_BIT | reg,
+					    val);
+	if (ret < 0)
+		dev_err(&bh1730->client->dev,
+			"i2c write failed error %d, register %01x\n",
+			ret, reg);
+
+	return ret;
+}
+
+static int bh1730_gain_multiplier(struct bh1730_data *bh1730)
+{
+	int multiplier;
+
+	switch (bh1730->gain) {
+	case BH1730_GAIN_1X:
+		multiplier = 1;
+		break;
+	case BH1730_GAIN_2X:
+		multiplier = 2;
+		break;
+	case BH1730_GAIN_64X:
+		multiplier = 64;
+		break;
+	case BH1730_GAIN_128X:
+		multiplier = 128;
+		break;
+	default:
+		multiplier = -EINVAL;
+		break;
+	}
+
+	if (multiplier < 0) {
+		dev_warn(&bh1730->client->dev,
+			 "invalid gain multiplier settings: %d\n",
+			 bh1730->gain);
+		bh1730->gain = BH1730_GAIN_1X;
+		multiplier = 1;
+	}
+
+	return multiplier;
+}
+
+static int bh1730_set_gain(struct bh1730_data *bh1730, enum bh1730_gain gain)
+{
+	int ret = bh1730_write(bh1730, BH1730_REG_GAIN, gain);
+
+	if (ret < 0)
+		return ret;
+
+	bh1730->gain = gain;
+
+	return 0;
+}
+
+static int bh1730_itime_us(struct bh1730_data *bh1730, int cycle)
+{
+	return (BH1730_ITIME_TO_US * cycle);
+}
+
+
+static int bh1730_set_integration_time_cycle(struct bh1730_data *bh1730,
+					  u32 cycle)
+{
+	int ret, itime;
+
+	itime = 256 - cycle;
+
+	/* ITIME == 0 is reserved for manual integration mode. */
+	if (itime <= 0 || itime > 255) {
+		dev_warn(&bh1730->client->dev,
+		"integration time out of range: %d cycles\n",
+		 cycle);
+
+		return -ERANGE;
+	}
+
+	ret = bh1730_write(bh1730, BH1730_REG_TIMING, itime);
+	if (ret < 0)
+		return ret;
+
+	bh1730->itime_us = bh1730_itime_us(bh1730, cycle);
+	bh1730->tmt_us = bh1730->itime_us + BH1730_ADC_CALC_DELAY_US;
+
+	return 0;
+}
+
+static int bh1730_adjust_gain(struct bh1730_data *bh1730)
+{
+	int visible, ir, highest, gain, ret;
+
+	visible = bh1730_read_word(bh1730, BH1730_REG_DATA0LOW);
+	if (visible < 0)
+		return visible;
+
+	ir = bh1730_read_word(bh1730, BH1730_REG_DATA1LOW);
+	if (ir < 0)
+		return ir;
+
+	highest = max(visible, ir);
+
+	/* Adjust gain based on sensitivity calibration */
+	gain = bh1730->gain;
+	if (highest > bh1730->cal.gain_coeff[gain].fl &&
+	    gain != BH1730_GAIN_1X) {
+		gain--; /* Decrease sensitivity */
+	} else if (highest < bh1730->cal.gain_coeff[gain].cl &&
+		   gain != BH1730_GAIN_128X) {
+		gain++; /* Increase sensitivity */
+	}
+
+	/* Clamp to proper gain values */
+	if (gain < 0)
+		gain = BH1730_GAIN_1X;
+	else if (gain > BH1730_GAIN_128X)
+		gain = BH1730_GAIN_128X;
+
+	if (gain != bh1730->gain) {
+		ret = bh1730_set_gain(bh1730, gain);
+		if (ret < 0)
+			return ret;
+
+		usleep_range(bh1730->tmt_us, bh1730->tmt_us + 1000);
+	}
+
+	return 0;
+}
+
+static int bh1730_get_lux(struct bh1730_data *bh1730)
+{
+	int i, visible, ir;
+	struct opt_win_coeff_t *opt_win_coeff;
+	u64 lux = 0;
+
+	visible = bh1730_read_word(bh1730, BH1730_REG_DATA0LOW);
+
+	/* If visible is 0, skip calculations */
+	if (visible <= 0)
+		return visible;
+
+	ir = bh1730_read_word(bh1730, BH1730_REG_DATA1LOW);
+	if (ir < 0)
+		return ir;
+
+	/* Calibrate based on optical window */
+	for (i = 0; i < bh1730->cal.opt_win_coeff_count; i++) {
+		opt_win_coeff = &bh1730->cal.opt_win_coeff[i];
+		if (1000 * ir / visible < opt_win_coeff->rc) {
+			lux = ((u64)opt_win_coeff->cv * visible) -
+				   (opt_win_coeff->ci * ir);
+			break;
+		}
+	}
+
+	/* Calculate lux */
+	lux *= BH1730_DEFAULT_ITIME_MS;
+	lux /= bh1730_gain_multiplier(bh1730) * bh1730->itime_us;
+	lux = (lux * bh1730->cal.mul) / 1000;
+
+	if (lux > BH1730_MAX_MEASURED_LUX)
+		lux = BH1730_MAX_MEASURED_LUX;
+
+	return (int)lux;
+}
+
+static int bh1730_power_ctrl(struct bh1730_data *bh1730, bool enable)
+{
+	struct device *dev = &bh1730->client->dev;
+	static bool enabled;
+	int ret = 0;
+
+	if (enabled == enable)
+		return ret;
+
+	if (enable) {
+		if (!IS_ERR_OR_NULL(bh1730->reg_vdd)) {
+			ret = regulator_enable(bh1730->reg_vdd);
+			if (ret) {
+				dev_err(dev, "%s: Failed to enable vdd: %d\n",
+					__func__, ret);
+				return ret;
+			}
+		}
+
+		if (!IS_ERR_OR_NULL(bh1730->reg_vid)) {
+			ret = regulator_enable(bh1730->reg_vid);
+			if (ret) {
+				dev_err(dev, "%s: Failed to enable vid: %d\n",
+					__func__, ret);
+				return ret;
+			}
+		}
+
+		usleep_range(BH1730_POWER_ON_DELAY_US, BH1730_POWER_ON_DELAY_US + 1000);
+	} else {
+		if (!IS_ERR_OR_NULL(bh1730->reg_vdd)) {
+			ret = regulator_disable(bh1730->reg_vdd);
+			if (ret) {
+				dev_err(dev, "%s: Failed to disable vdd: %d\n",
+					__func__, ret);
+				return ret;
+			}
+		}
+
+		if (!IS_ERR_OR_NULL(bh1730->reg_vid)) {
+			ret = regulator_disable(bh1730->reg_vid);
+			if (ret) {
+				dev_err(dev, "%s: Failed to disable vid: %d\n",
+					__func__, ret);
+				return ret;
+			}
+		}
+	}
+
+	enabled = enable;
+
+	return ret;
+}
+
+static int bh1730_power_on(struct bh1730_data *bh1730)
+{
+	int ret = bh1730_power_ctrl(bh1730, true);
+
+	if (ret < 0)
+		return ret;
+
+	return bh1730_write(bh1730, BH1730_REG_CONTROL,
+			    BH1730_CONTROL_POWER | BH1730_CONTROL_ADC_EN);
+}
+
+static int bh1730_init_config(struct bh1730_data *bh1730)
+{
+	int ret;
+
+	ret = bh1730_set_gain(bh1730, BH1730_GAIN_64X);
+	if (ret < 0)
+		return ret;
+
+	return bh1730_set_integration_time_cycle(bh1730,
+						bh1730->cal.itime_cycle);
+}
+
+static int bh1730_power_off(struct bh1730_data *bh1730)
+{
+	int ret = bh1730_write(bh1730, BH1730_REG_CONTROL, 0);
+
+	if (ret < 0)
+		return ret;
+
+	return bh1730_power_ctrl(bh1730, false);
+}
+
+static int bh1730_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	struct bh1730_data *bh1730 = iio_priv(indio_dev);
+	int data_reg, ret;
+
+	ret = bh1730_adjust_gain(bh1730);
+	if (ret < 0)
+		return ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_PROCESSED:
+		ret = bh1730_get_lux(bh1730);
+		if (ret < 0)
+			return ret;
+		*val = ret;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_RAW:
+		switch (chan->channel2) {
+		case IIO_MOD_LIGHT_CLEAR:
+			data_reg = BH1730_REG_DATA0LOW;
+			break;
+		case IIO_MOD_LIGHT_IR:
+			data_reg = BH1730_REG_DATA1LOW;
+			break;
+		default:
+			return -EINVAL;
+		}
+		ret = bh1730_read_word(bh1730, data_reg);
+		if (ret < 0)
+			return ret;
+		ret = ret * 1000 / bh1730_gain_multiplier(bh1730);
+		*val = ret / 1000;
+		*val2 = (ret % 1000) * 1000;
+		return IIO_VAL_INT_PLUS_MICRO;
+	case IIO_CHAN_INFO_INT_TIME:
+		*val = 0;
+		*val2 = bh1730->itime_us;
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int bh1730_parse_dt(struct bh1730_data *bh1730, struct device_node *dn)
+{
+	struct device *dev = &bh1730->client->dev;
+	int ret;
+	u32 *opt_win_coeff = NULL;
+	u32 *gain_coeff = NULL;
+	int opt_win_coeff_count = 0, gain_coeff_count = 0, cycle = 0, mul = 0;
+
+	memcpy(&bh1730->cal, &def_lux_data, sizeof(struct lux_cal_data_t));
+
+	if (dn) {
+		/* Get regulators */
+		bh1730->reg_vdd = regulator_get(dev, "als-vdd");
+		if (IS_ERR_OR_NULL(bh1730->reg_vdd)) {
+			bh1730->reg_vdd = NULL;
+			dev_warn(dev, "failed to get als-vdd");
+		}
+
+		bh1730->reg_vid = regulator_get(dev, "als-vid");
+		if (IS_ERR_OR_NULL(bh1730->reg_vid)) {
+			bh1730->reg_vid = NULL;
+			dev_warn(dev, "failed to get als-vid");
+		}
+
+		/* Get calibration */
+		ret = of_property_read_u32(dn,
+				"rohm,integration-cycle", &cycle);
+		if (ret < 0)
+			goto out;
+
+		ret = of_property_read_u32(dn,
+				"rohm,lux-multiplier", &mul);
+		if (ret < 0)
+			goto out;
+
+		if (cycle == 0 || mul == 0)
+			goto out;
+
+		/* Get optical window coefficients */
+		opt_win_coeff_count = of_property_count_elems_of_size(dn,
+					"rohm,opt-win-coeff", sizeof(u32));
+		if (opt_win_coeff_count > 0) {
+			opt_win_coeff = devm_kzalloc(dev,
+						sizeof(u32) * opt_win_coeff_count,
+						GFP_KERNEL);
+			if (!opt_win_coeff) {
+				dev_err(dev, "failed to allocate mem for opt_win_coeff");
+				return -ENOMEM;
+			}
+
+			ret = of_property_read_u32_array(dn, "rohm,opt-win-coeff",
+					opt_win_coeff, opt_win_coeff_count);
+
+			if (ret) {
+				devm_kfree(dev, opt_win_coeff);
+				goto out;
+			}
+		}
+
+		/* Get gain sensitivity coefficients */
+		gain_coeff_count = of_property_count_elems_of_size(dn,
+					"rohm,gain-coeff", sizeof(u32));
+
+		if (gain_coeff_count == 8) { /* 2 for each gain supported */
+			gain_coeff = devm_kzalloc(dev,
+					sizeof(u32) * gain_coeff_count,
+					GFP_KERNEL);
+			if (!gain_coeff) {
+				dev_err(dev, "failed to allocate mem for gain_coeff");
+				return -ENOMEM;
+			}
+
+			ret = of_property_read_u32_array(dn, "rohm,gain-coeff",
+					gain_coeff, gain_coeff_count);
+			if (ret) {
+				if (opt_win_coeff)
+					devm_kfree(dev, opt_win_coeff);
+				devm_kfree(dev, gain_coeff);
+				goto out;
+			}
+		}
+
+		if (opt_win_coeff) {
+			bh1730->cal.opt_win_coeff =
+					(struct opt_win_coeff_t *)opt_win_coeff;
+			bh1730->cal.opt_win_coeff_count =
+					opt_win_coeff_count /
+					(sizeof(struct opt_win_coeff_t) /
+					sizeof(u32));
+		}
+
+		if (gain_coeff)
+			bh1730->cal.gain_coeff = (struct gain_coeff_t *)gain_coeff;
+
+		bh1730->cal.itime_cycle = cycle;
+		bh1730->cal.mul = mul;
+
+		return 0;
+	}
+
+out:
+	dev_info(&bh1730->client->dev, "using default calibration");
+
+	return 0;
+}
+
+static const struct iio_info bh1730_info = {
+	.read_raw = bh1730_read_raw,
+};
+
+static const struct iio_chan_spec bh1730_channels[] = {
+	{
+		.type = IIO_LIGHT,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+				      BIT(IIO_CHAN_INFO_INT_TIME),
+	},
+	{
+		.type = IIO_INTENSITY,
+		.modified = 1,
+		.channel2 = IIO_MOD_LIGHT_CLEAR,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+	},
+	{
+		.type = IIO_INTENSITY,
+		.modified = 1,
+		.channel2 = IIO_MOD_LIGHT_IR,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+	},
+};
+
+static int bh1730_probe(struct i2c_client *client)
+{
+	struct bh1730_data *bh1730;
+	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+	struct iio_dev *indio_dev;
+	int ret;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
+		return -EIO;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*bh1730));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	bh1730 = iio_priv(indio_dev);
+	bh1730->client = client;
+	i2c_set_clientdata(client, indio_dev);
+
+	ret = bh1730_parse_dt(bh1730, client->dev.of_node);
+	if (ret < 0)
+		return ret;
+
+	ret = bh1730_power_on(bh1730);
+	if (ret < 0)
+		return ret;
+
+	ret = bh1730_init_config(bh1730);
+	if (ret < 0)
+		return ret;
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &bh1730_info;
+	indio_dev->name = "bh1730";
+	indio_dev->channels = bh1730_channels;
+	indio_dev->num_channels = ARRAY_SIZE(bh1730_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto out_power_off;
+
+	return 0;
+
+out_power_off:
+	dev_info(&client->dev, "%s: failed\n", __func__);
+	bh1730_power_off(bh1730);
+	return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int bh1730_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct bh1730_data *bh1730 = iio_priv(indio_dev);
+
+	bh1730_power_off(bh1730);
+
+	return 0;
+}
+
+static int bh1730_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct bh1730_data *bh1730 = iio_priv(indio_dev);
+	int ret;
+
+	ret = bh1730_power_on(bh1730);
+	if (ret < 0)
+		return ret;
+
+	return bh1730_init_config(bh1730);
+}
+
+static SIMPLE_DEV_PM_OPS(bh1730_pm_ops, bh1730_suspend, bh1730_resume);
+#endif
+
+static void bh1730_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct bh1730_data *bh1730 = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	bh1730_power_off(bh1730);
+}
+
+static const struct i2c_device_id bh1730_i2c_device_id[] = {
+	{ BH1730_NAME, 0 },
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, bh1730_i2c_device_id);
+
+static const struct of_device_id of_bh1730_match[] = {
+	{ .compatible = "rohm,bh1730fvc" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, of_bh1730_match);
+
+static struct i2c_driver bh1730_driver = {
+	.probe = bh1730_probe,
+	.remove = bh1730_remove,
+	.driver = {
+		.name = BH1730_NAME,
+		.owner		= THIS_MODULE,
+		.of_match_table = of_bh1730_match,
+#ifdef CONFIG_PM_SLEEP
+		.pm		= &bh1730_pm_ops,
+#endif
+	},
+	.id_table = bh1730_i2c_device_id,
+};
+module_i2c_driver(bh1730_driver);
+
+MODULE_AUTHOR("CTCaer <ctcaer@gmail.com>");
+MODULE_DESCRIPTION("ROHM BH1730FVC driver");
+MODULE_LICENSE("GPL v2");

-- 
2.54.0