Adding upstream version 4.19.249.upstream/4.19.249

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

1 files changed, 637 insertions, 0 deletions

diff --git a/drivers/iio/health/afe4404.c b/drivers/iio/health/afe4404.c
new file mode 100644
index 000000000..23e1ac650
--- /dev/null
+++ b/drivers/iio/health/afe4404.c
@@ -0,0 +1,637 @@
+/*
+ * AFE4404 Heart Rate Monitors and Low-Cost Pulse Oximeters
+ *
+ * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
+ *	Andrew F. Davis <afd@ti.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.
+ *
+ * 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/device.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/sysfs.h>
+#include <linux/regulator/consumer.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+#include "afe440x.h"
+
+#define AFE4404_DRIVER_NAME		"afe4404"
+
+/* AFE4404 registers */
+#define AFE4404_TIA_GAIN_SEP		0x20
+#define AFE4404_TIA_GAIN		0x21
+#define AFE4404_PROG_TG_STC		0x34
+#define AFE4404_PROG_TG_ENDC		0x35
+#define AFE4404_LED3LEDSTC		0x36
+#define AFE4404_LED3LEDENDC		0x37
+#define AFE4404_CLKDIV_PRF		0x39
+#define AFE4404_OFFDAC			0x3a
+#define AFE4404_DEC			0x3d
+#define AFE4404_AVG_LED2_ALED2VAL	0x3f
+#define AFE4404_AVG_LED1_ALED1VAL	0x40
+
+/* AFE4404 CONTROL2 register fields */
+#define AFE440X_CONTROL2_OSC_ENABLE	BIT(9)
+
+enum afe4404_fields {
+	/* Gains */
+	F_TIA_GAIN_SEP, F_TIA_CF_SEP,
+	F_TIA_GAIN, TIA_CF,
+
+	/* LED Current */
+	F_ILED1, F_ILED2, F_ILED3,
+
+	/* Offset DAC */
+	F_OFFDAC_AMB2, F_OFFDAC_LED1, F_OFFDAC_AMB1, F_OFFDAC_LED2,
+
+	/* sentinel */
+	F_MAX_FIELDS
+};
+
+static const struct reg_field afe4404_reg_fields[] = {
+	/* Gains */
+	[F_TIA_GAIN_SEP]	= REG_FIELD(AFE4404_TIA_GAIN_SEP, 0, 2),
+	[F_TIA_CF_SEP]		= REG_FIELD(AFE4404_TIA_GAIN_SEP, 3, 5),
+	[F_TIA_GAIN]		= REG_FIELD(AFE4404_TIA_GAIN, 0, 2),
+	[TIA_CF]		= REG_FIELD(AFE4404_TIA_GAIN, 3, 5),
+	/* LED Current */
+	[F_ILED1]		= REG_FIELD(AFE440X_LEDCNTRL, 0, 5),
+	[F_ILED2]		= REG_FIELD(AFE440X_LEDCNTRL, 6, 11),
+	[F_ILED3]		= REG_FIELD(AFE440X_LEDCNTRL, 12, 17),
+	/* Offset DAC */
+	[F_OFFDAC_AMB2]		= REG_FIELD(AFE4404_OFFDAC, 0, 4),
+	[F_OFFDAC_LED1]		= REG_FIELD(AFE4404_OFFDAC, 5, 9),
+	[F_OFFDAC_AMB1]		= REG_FIELD(AFE4404_OFFDAC, 10, 14),
+	[F_OFFDAC_LED2]		= REG_FIELD(AFE4404_OFFDAC, 15, 19),
+};
+
+/**
+ * struct afe4404_data - AFE4404 device instance data
+ * @dev: Device structure
+ * @regmap: Register map of the device
+ * @fields: Register fields of the device
+ * @regulator: Pointer to the regulator for the IC
+ * @trig: IIO trigger for this device
+ * @irq: ADC_RDY line interrupt number
+ * @buffer: Used to construct a scan to push to the iio buffer.
+ */
+struct afe4404_data {
+	struct device *dev;
+	struct regmap *regmap;
+	struct regmap_field *fields[F_MAX_FIELDS];
+	struct regulator *regulator;
+	struct iio_trigger *trig;
+	int irq;
+	s32 buffer[10] __aligned(8);
+};
+
+enum afe4404_chan_id {
+	LED2 = 1,
+	ALED2,
+	LED1,
+	ALED1,
+	LED2_ALED2,
+	LED1_ALED1,
+};
+
+static const unsigned int afe4404_channel_values[] = {
+	[LED2] = AFE440X_LED2VAL,
+	[ALED2] = AFE440X_ALED2VAL,
+	[LED1] = AFE440X_LED1VAL,
+	[ALED1] = AFE440X_ALED1VAL,
+	[LED2_ALED2] = AFE440X_LED2_ALED2VAL,
+	[LED1_ALED1] = AFE440X_LED1_ALED1VAL,
+};
+
+static const unsigned int afe4404_channel_leds[] = {
+	[LED2] = F_ILED2,
+	[ALED2] = F_ILED3,
+	[LED1] = F_ILED1,
+};
+
+static const unsigned int afe4404_channel_offdacs[] = {
+	[LED2] = F_OFFDAC_LED2,
+	[ALED2] = F_OFFDAC_AMB2,
+	[LED1] = F_OFFDAC_LED1,
+	[ALED1] = F_OFFDAC_AMB1,
+};
+
+static const struct iio_chan_spec afe4404_channels[] = {
+	/* ADC values */
+	AFE440X_INTENSITY_CHAN(LED2, BIT(IIO_CHAN_INFO_OFFSET)),
+	AFE440X_INTENSITY_CHAN(ALED2, BIT(IIO_CHAN_INFO_OFFSET)),
+	AFE440X_INTENSITY_CHAN(LED1, BIT(IIO_CHAN_INFO_OFFSET)),
+	AFE440X_INTENSITY_CHAN(ALED1, BIT(IIO_CHAN_INFO_OFFSET)),
+	AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
+	AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
+	/* LED current */
+	AFE440X_CURRENT_CHAN(LED2),
+	AFE440X_CURRENT_CHAN(ALED2),
+	AFE440X_CURRENT_CHAN(LED1),
+};
+
+static const struct afe440x_val_table afe4404_res_table[] = {
+	{ .integer = 500000, .fract = 0 },
+	{ .integer = 250000, .fract = 0 },
+	{ .integer = 100000, .fract = 0 },
+	{ .integer = 50000, .fract = 0 },
+	{ .integer = 25000, .fract = 0 },
+	{ .integer = 10000, .fract = 0 },
+	{ .integer = 1000000, .fract = 0 },
+	{ .integer = 2000000, .fract = 0 },
+};
+AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4404_res_table);
+
+static const struct afe440x_val_table afe4404_cap_table[] = {
+	{ .integer = 0, .fract = 5000 },
+	{ .integer = 0, .fract = 2500 },
+	{ .integer = 0, .fract = 10000 },
+	{ .integer = 0, .fract = 7500 },
+	{ .integer = 0, .fract = 20000 },
+	{ .integer = 0, .fract = 17500 },
+	{ .integer = 0, .fract = 25000 },
+	{ .integer = 0, .fract = 22500 },
+};
+AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4404_cap_table);
+
+static ssize_t afe440x_show_register(struct device *dev,
+				     struct device_attribute *attr,
+				     char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct afe4404_data *afe = iio_priv(indio_dev);
+	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
+	unsigned int reg_val;
+	int vals[2];
+	int ret;
+
+	ret = regmap_field_read(afe->fields[afe440x_attr->field], &reg_val);
+	if (ret)
+		return ret;
+
+	if (reg_val >= afe440x_attr->table_size)
+		return -EINVAL;
+
+	vals[0] = afe440x_attr->val_table[reg_val].integer;
+	vals[1] = afe440x_attr->val_table[reg_val].fract;
+
+	return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
+}
+
+static ssize_t afe440x_store_register(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct afe4404_data *afe = iio_priv(indio_dev);
+	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
+	int val, integer, fract, ret;
+
+	ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
+	if (ret)
+		return ret;
+
+	for (val = 0; val < afe440x_attr->table_size; val++)
+		if (afe440x_attr->val_table[val].integer == integer &&
+		    afe440x_attr->val_table[val].fract == fract)
+			break;
+	if (val == afe440x_attr->table_size)
+		return -EINVAL;
+
+	ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
+	if (ret)
+		return ret;
+
+	return count;
+}
+
+static AFE440X_ATTR(in_intensity1_resistance, F_TIA_GAIN_SEP, afe4404_res_table);
+static AFE440X_ATTR(in_intensity1_capacitance, F_TIA_CF_SEP, afe4404_cap_table);
+
+static AFE440X_ATTR(in_intensity2_resistance, F_TIA_GAIN_SEP, afe4404_res_table);
+static AFE440X_ATTR(in_intensity2_capacitance, F_TIA_CF_SEP, afe4404_cap_table);
+
+static AFE440X_ATTR(in_intensity3_resistance, F_TIA_GAIN, afe4404_res_table);
+static AFE440X_ATTR(in_intensity3_capacitance, TIA_CF, afe4404_cap_table);
+
+static AFE440X_ATTR(in_intensity4_resistance, F_TIA_GAIN, afe4404_res_table);
+static AFE440X_ATTR(in_intensity4_capacitance, TIA_CF, afe4404_cap_table);
+
+static struct attribute *afe440x_attributes[] = {
+	&dev_attr_in_intensity_resistance_available.attr,
+	&dev_attr_in_intensity_capacitance_available.attr,
+	&afe440x_attr_in_intensity1_resistance.dev_attr.attr,
+	&afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
+	&afe440x_attr_in_intensity2_resistance.dev_attr.attr,
+	&afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
+	&afe440x_attr_in_intensity3_resistance.dev_attr.attr,
+	&afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
+	&afe440x_attr_in_intensity4_resistance.dev_attr.attr,
+	&afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group afe440x_attribute_group = {
+	.attrs = afe440x_attributes
+};
+
+static int afe4404_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct afe4404_data *afe = iio_priv(indio_dev);
+	unsigned int value_reg = afe4404_channel_values[chan->address];
+	unsigned int led_field = afe4404_channel_leds[chan->address];
+	unsigned int offdac_field = afe4404_channel_offdacs[chan->address];
+	int ret;
+
+	switch (chan->type) {
+	case IIO_INTENSITY:
+		switch (mask) {
+		case IIO_CHAN_INFO_RAW:
+			ret = regmap_read(afe->regmap, value_reg, val);
+			if (ret)
+				return ret;
+			return IIO_VAL_INT;
+		case IIO_CHAN_INFO_OFFSET:
+			ret = regmap_field_read(afe->fields[offdac_field], val);
+			if (ret)
+				return ret;
+			return IIO_VAL_INT;
+		}
+		break;
+	case IIO_CURRENT:
+		switch (mask) {
+		case IIO_CHAN_INFO_RAW:
+			ret = regmap_field_read(afe->fields[led_field], val);
+			if (ret)
+				return ret;
+			return IIO_VAL_INT;
+		case IIO_CHAN_INFO_SCALE:
+			*val = 0;
+			*val2 = 800000;
+			return IIO_VAL_INT_PLUS_MICRO;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int afe4404_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct afe4404_data *afe = iio_priv(indio_dev);
+	unsigned int led_field = afe4404_channel_leds[chan->address];
+	unsigned int offdac_field = afe4404_channel_offdacs[chan->address];
+
+	switch (chan->type) {
+	case IIO_INTENSITY:
+		switch (mask) {
+		case IIO_CHAN_INFO_OFFSET:
+			return regmap_field_write(afe->fields[offdac_field], val);
+		}
+		break;
+	case IIO_CURRENT:
+		switch (mask) {
+		case IIO_CHAN_INFO_RAW:
+			return regmap_field_write(afe->fields[led_field], val);
+		}
+		break;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info afe4404_iio_info = {
+	.attrs = &afe440x_attribute_group,
+	.read_raw = afe4404_read_raw,
+	.write_raw = afe4404_write_raw,
+};
+
+static irqreturn_t afe4404_trigger_handler(int irq, void *private)
+{
+	struct iio_poll_func *pf = private;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct afe4404_data *afe = iio_priv(indio_dev);
+	int ret, bit, i = 0;
+
+	for_each_set_bit(bit, indio_dev->active_scan_mask,
+			 indio_dev->masklength) {
+		ret = regmap_read(afe->regmap, afe4404_channel_values[bit],
+				  &afe->buffer[i++]);
+		if (ret)
+			goto err;
+	}
+
+	iio_push_to_buffers_with_timestamp(indio_dev, afe->buffer,
+					   pf->timestamp);
+err:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static const struct iio_trigger_ops afe4404_trigger_ops = {
+};
+
+/* Default timings from data-sheet */
+#define AFE4404_TIMING_PAIRS			\
+	{ AFE440X_PRPCOUNT,	39999	},	\
+	{ AFE440X_LED2LEDSTC,	0	},	\
+	{ AFE440X_LED2LEDENDC,	398	},	\
+	{ AFE440X_LED2STC,	80	},	\
+	{ AFE440X_LED2ENDC,	398	},	\
+	{ AFE440X_ADCRSTSTCT0,	5600	},	\
+	{ AFE440X_ADCRSTENDCT0,	5606	},	\
+	{ AFE440X_LED2CONVST,	5607	},	\
+	{ AFE440X_LED2CONVEND,	6066	},	\
+	{ AFE4404_LED3LEDSTC,	400	},	\
+	{ AFE4404_LED3LEDENDC,	798	},	\
+	{ AFE440X_ALED2STC,	480	},	\
+	{ AFE440X_ALED2ENDC,	798	},	\
+	{ AFE440X_ADCRSTSTCT1,	6068	},	\
+	{ AFE440X_ADCRSTENDCT1,	6074	},	\
+	{ AFE440X_ALED2CONVST,	6075	},	\
+	{ AFE440X_ALED2CONVEND,	6534	},	\
+	{ AFE440X_LED1LEDSTC,	800	},	\
+	{ AFE440X_LED1LEDENDC,	1198	},	\
+	{ AFE440X_LED1STC,	880	},	\
+	{ AFE440X_LED1ENDC,	1198	},	\
+	{ AFE440X_ADCRSTSTCT2,	6536	},	\
+	{ AFE440X_ADCRSTENDCT2,	6542	},	\
+	{ AFE440X_LED1CONVST,	6543	},	\
+	{ AFE440X_LED1CONVEND,	7003	},	\
+	{ AFE440X_ALED1STC,	1280	},	\
+	{ AFE440X_ALED1ENDC,	1598	},	\
+	{ AFE440X_ADCRSTSTCT3,	7005	},	\
+	{ AFE440X_ADCRSTENDCT3,	7011	},	\
+	{ AFE440X_ALED1CONVST,	7012	},	\
+	{ AFE440X_ALED1CONVEND,	7471	},	\
+	{ AFE440X_PDNCYCLESTC,	7671	},	\
+	{ AFE440X_PDNCYCLEENDC,	39199	}
+
+static const struct reg_sequence afe4404_reg_sequences[] = {
+	AFE4404_TIMING_PAIRS,
+	{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
+	{ AFE4404_TIA_GAIN_SEP, AFE440X_TIAGAIN_ENSEPGAIN },
+	{ AFE440X_CONTROL2, AFE440X_CONTROL2_OSC_ENABLE	},
+};
+
+static const struct regmap_range afe4404_yes_ranges[] = {
+	regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
+	regmap_reg_range(AFE4404_AVG_LED2_ALED2VAL, AFE4404_AVG_LED1_ALED1VAL),
+};
+
+static const struct regmap_access_table afe4404_volatile_table = {
+	.yes_ranges = afe4404_yes_ranges,
+	.n_yes_ranges = ARRAY_SIZE(afe4404_yes_ranges),
+};
+
+static const struct regmap_config afe4404_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 24,
+
+	.max_register = AFE4404_AVG_LED1_ALED1VAL,
+	.cache_type = REGCACHE_RBTREE,
+	.volatile_table = &afe4404_volatile_table,
+};
+
+static const struct of_device_id afe4404_of_match[] = {
+	{ .compatible = "ti,afe4404", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, afe4404_of_match);
+
+static int __maybe_unused afe4404_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct afe4404_data *afe = iio_priv(indio_dev);
+	int ret;
+
+	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
+				 AFE440X_CONTROL2_PDN_AFE,
+				 AFE440X_CONTROL2_PDN_AFE);
+	if (ret)
+		return ret;
+
+	ret = regulator_disable(afe->regulator);
+	if (ret) {
+		dev_err(dev, "Unable to disable regulator\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused afe4404_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct afe4404_data *afe = iio_priv(indio_dev);
+	int ret;
+
+	ret = regulator_enable(afe->regulator);
+	if (ret) {
+		dev_err(dev, "Unable to enable regulator\n");
+		return ret;
+	}
+
+	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
+				 AFE440X_CONTROL2_PDN_AFE, 0);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(afe4404_pm_ops, afe4404_suspend, afe4404_resume);
+
+static int afe4404_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct iio_dev *indio_dev;
+	struct afe4404_data *afe;
+	int i, ret;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*afe));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	afe = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+
+	afe->dev = &client->dev;
+	afe->irq = client->irq;
+
+	afe->regmap = devm_regmap_init_i2c(client, &afe4404_regmap_config);
+	if (IS_ERR(afe->regmap)) {
+		dev_err(afe->dev, "Unable to allocate register map\n");
+		return PTR_ERR(afe->regmap);
+	}
+
+	for (i = 0; i < F_MAX_FIELDS; i++) {
+		afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap,
+							 afe4404_reg_fields[i]);
+		if (IS_ERR(afe->fields[i])) {
+			dev_err(afe->dev, "Unable to allocate regmap fields\n");
+			return PTR_ERR(afe->fields[i]);
+		}
+	}
+
+	afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
+	if (IS_ERR(afe->regulator)) {
+		dev_err(afe->dev, "Unable to get regulator\n");
+		return PTR_ERR(afe->regulator);
+	}
+	ret = regulator_enable(afe->regulator);
+	if (ret) {
+		dev_err(afe->dev, "Unable to enable regulator\n");
+		return ret;
+	}
+
+	ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
+			   AFE440X_CONTROL0_SW_RESET);
+	if (ret) {
+		dev_err(afe->dev, "Unable to reset device\n");
+		goto disable_reg;
+	}
+
+	ret = regmap_multi_reg_write(afe->regmap, afe4404_reg_sequences,
+				     ARRAY_SIZE(afe4404_reg_sequences));
+	if (ret) {
+		dev_err(afe->dev, "Unable to set register defaults\n");
+		goto disable_reg;
+	}
+
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->dev.parent = afe->dev;
+	indio_dev->channels = afe4404_channels;
+	indio_dev->num_channels = ARRAY_SIZE(afe4404_channels);
+	indio_dev->name = AFE4404_DRIVER_NAME;
+	indio_dev->info = &afe4404_iio_info;
+
+	if (afe->irq > 0) {
+		afe->trig = devm_iio_trigger_alloc(afe->dev,
+						   "%s-dev%d",
+						   indio_dev->name,
+						   indio_dev->id);
+		if (!afe->trig) {
+			dev_err(afe->dev, "Unable to allocate IIO trigger\n");
+			ret = -ENOMEM;
+			goto disable_reg;
+		}
+
+		iio_trigger_set_drvdata(afe->trig, indio_dev);
+
+		afe->trig->ops = &afe4404_trigger_ops;
+		afe->trig->dev.parent = afe->dev;
+
+		ret = iio_trigger_register(afe->trig);
+		if (ret) {
+			dev_err(afe->dev, "Unable to register IIO trigger\n");
+			goto disable_reg;
+		}
+
+		ret = devm_request_threaded_irq(afe->dev, afe->irq,
+						iio_trigger_generic_data_rdy_poll,
+						NULL, IRQF_ONESHOT,
+						AFE4404_DRIVER_NAME,
+						afe->trig);
+		if (ret) {
+			dev_err(afe->dev, "Unable to request IRQ\n");
+			goto disable_reg;
+		}
+	}
+
+	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
+					 afe4404_trigger_handler, NULL);
+	if (ret) {
+		dev_err(afe->dev, "Unable to setup buffer\n");
+		goto unregister_trigger;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		dev_err(afe->dev, "Unable to register IIO device\n");
+		goto unregister_triggered_buffer;
+	}
+
+	return 0;
+
+unregister_triggered_buffer:
+	iio_triggered_buffer_cleanup(indio_dev);
+unregister_trigger:
+	if (afe->irq > 0)
+		iio_trigger_unregister(afe->trig);
+disable_reg:
+	regulator_disable(afe->regulator);
+
+	return ret;
+}
+
+static int afe4404_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct afe4404_data *afe = iio_priv(indio_dev);
+	int ret;
+
+	iio_device_unregister(indio_dev);
+
+	iio_triggered_buffer_cleanup(indio_dev);
+
+	if (afe->irq > 0)
+		iio_trigger_unregister(afe->trig);
+
+	ret = regulator_disable(afe->regulator);
+	if (ret) {
+		dev_err(afe->dev, "Unable to disable regulator\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct i2c_device_id afe4404_ids[] = {
+	{ "afe4404", 0 },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, afe4404_ids);
+
+static struct i2c_driver afe4404_i2c_driver = {
+	.driver = {
+		.name = AFE4404_DRIVER_NAME,
+		.of_match_table = afe4404_of_match,
+		.pm = &afe4404_pm_ops,
+	},
+	.probe = afe4404_probe,
+	.remove = afe4404_remove,
+	.id_table = afe4404_ids,
+};
+module_i2c_driver(afe4404_i2c_driver);
+
+MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
+MODULE_DESCRIPTION("TI AFE4404 Heart Rate Monitor and Pulse Oximeter AFE");
+MODULE_LICENSE("GPL v2");