Adding upstream version 4.19.249.upstream/4.19.249upstream

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

7 files changed, 2666 insertions, 0 deletions

diff --git a/drivers/iio/health/Kconfig b/drivers/iio/health/Kconfig
new file mode 100644
index 000000000..a2ecb4c94
--- /dev/null
+++ b/drivers/iio/health/Kconfig
@@ -0,0 +1,64 @@
+#
+# Health sensors
+#
+# When adding new entries keep the list in alphabetical order
+
+menu "Health Sensors"
+
+menu "Heart Rate Monitors"
+
+config AFE4403
+	tristate "TI AFE4403 Heart Rate Monitor"
+	depends on SPI_MASTER
+	select REGMAP_SPI
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes to choose the Texas Instruments AFE4403
+	  heart rate monitor and low-cost pulse oximeter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called afe4403.
+
+config AFE4404
+	tristate "TI AFE4404 heart rate and pulse oximeter sensor"
+	depends on I2C
+	select REGMAP_I2C
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes to choose the Texas Instruments AFE4404
+	  heart rate monitor and low-cost pulse oximeter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called afe4404.
+
+config MAX30100
+	tristate "MAX30100 heart rate and pulse oximeter sensor"
+	depends on I2C
+	select REGMAP_I2C
+	select IIO_BUFFER
+	select IIO_KFIFO_BUF
+	help
+	  Say Y here to build I2C interface support for the Maxim
+	  MAX30100 heart rate, and pulse oximeter sensor.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called max30100.
+
+config MAX30102
+	tristate "MAX30102 heart rate and pulse oximeter sensor"
+	depends on I2C
+	select REGMAP_I2C
+	select IIO_BUFFER
+	select IIO_KFIFO_BUF
+	help
+	  Say Y here to build I2C interface support for the Maxim
+	  MAX30102 heart rate, and pulse oximeter sensor.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called max30102.
+
+endmenu
+
+endmenu
diff --git a/drivers/iio/health/Makefile b/drivers/iio/health/Makefile
new file mode 100644
index 000000000..3558f9d64
--- /dev/null
+++ b/drivers/iio/health/Makefile
@@ -0,0 +1,10 @@
+#
+# Makefile for IIO Health sensors
+#
+
+# When adding new entries keep the list in alphabetical order
+
+obj-$(CONFIG_AFE4403)		+= afe4403.o
+obj-$(CONFIG_AFE4404)		+= afe4404.o
+obj-$(CONFIG_MAX30100)		+= max30100.o
+obj-$(CONFIG_MAX30102)		+= max30102.o
diff --git a/drivers/iio/health/afe4403.c b/drivers/iio/health/afe4403.c
new file mode 100644
index 000000000..63210a3b1
--- /dev/null
+++ b/drivers/iio/health/afe4403.c
@@ -0,0 +1,632 @@
+/*
+ * AFE4403 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/kernel.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.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 AFE4403_DRIVER_NAME		"afe4403"
+
+/* AFE4403 Registers */
+#define AFE4403_TIAGAIN			0x20
+#define AFE4403_TIA_AMB_GAIN		0x21
+
+enum afe4403_fields {
+	/* Gains */
+	F_RF_LED1, F_CF_LED1,
+	F_RF_LED, F_CF_LED,
+
+	/* LED Current */
+	F_ILED1, F_ILED2,
+
+	/* sentinel */
+	F_MAX_FIELDS
+};
+
+static const struct reg_field afe4403_reg_fields[] = {
+	/* Gains */
+	[F_RF_LED1]	= REG_FIELD(AFE4403_TIAGAIN, 0, 2),
+	[F_CF_LED1]	= REG_FIELD(AFE4403_TIAGAIN, 3, 7),
+	[F_RF_LED]	= REG_FIELD(AFE4403_TIA_AMB_GAIN, 0, 2),
+	[F_CF_LED]	= REG_FIELD(AFE4403_TIA_AMB_GAIN, 3, 7),
+	/* LED Current */
+	[F_ILED1]	= REG_FIELD(AFE440X_LEDCNTRL, 0, 7),
+	[F_ILED2]	= REG_FIELD(AFE440X_LEDCNTRL, 8, 15),
+};
+
+/**
+ * struct afe4403_data - AFE4403 device instance data
+ * @dev: Device structure
+ * @spi: SPI device handle
+ * @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 data layout to push into IIO buffer.
+ */
+struct afe4403_data {
+	struct device *dev;
+	struct spi_device *spi;
+	struct regmap *regmap;
+	struct regmap_field *fields[F_MAX_FIELDS];
+	struct regulator *regulator;
+	struct iio_trigger *trig;
+	int irq;
+	/* Ensure suitable alignment for timestamp */
+	s32 buffer[8] __aligned(8);
+};
+
+enum afe4403_chan_id {
+	LED2 = 1,
+	ALED2,
+	LED1,
+	ALED1,
+	LED2_ALED2,
+	LED1_ALED1,
+};
+
+static const unsigned int afe4403_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 afe4403_channel_leds[] = {
+	[LED2] = F_ILED2,
+	[LED1] = F_ILED1,
+};
+
+static const struct iio_chan_spec afe4403_channels[] = {
+	/* ADC values */
+	AFE440X_INTENSITY_CHAN(LED2, 0),
+	AFE440X_INTENSITY_CHAN(ALED2, 0),
+	AFE440X_INTENSITY_CHAN(LED1, 0),
+	AFE440X_INTENSITY_CHAN(ALED1, 0),
+	AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
+	AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
+	/* LED current */
+	AFE440X_CURRENT_CHAN(LED2),
+	AFE440X_CURRENT_CHAN(LED1),
+};
+
+static const struct afe440x_val_table afe4403_res_table[] = {
+	{ 500000 }, { 250000 }, { 100000 }, { 50000 },
+	{ 25000 }, { 10000 }, { 1000000 }, { 0 },
+};
+AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4403_res_table);
+
+static const struct afe440x_val_table afe4403_cap_table[] = {
+	{ 0, 5000 }, { 0, 10000 }, { 0, 20000 }, { 0, 25000 },
+	{ 0, 30000 }, { 0, 35000 }, { 0, 45000 }, { 0, 50000 },
+	{ 0, 55000 }, { 0, 60000 }, { 0, 70000 }, { 0, 75000 },
+	{ 0, 80000 }, { 0, 85000 }, { 0, 95000 }, { 0, 100000 },
+	{ 0, 155000 }, { 0, 160000 }, { 0, 170000 }, { 0, 175000 },
+	{ 0, 180000 }, { 0, 185000 }, { 0, 195000 }, { 0, 200000 },
+	{ 0, 205000 }, { 0, 210000 }, { 0, 220000 }, { 0, 225000 },
+	{ 0, 230000 }, { 0, 235000 }, { 0, 245000 }, { 0, 250000 },
+};
+AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4403_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 afe4403_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 afe4403_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_RF_LED, afe4403_res_table);
+static AFE440X_ATTR(in_intensity1_capacitance, F_CF_LED, afe4403_cap_table);
+
+static AFE440X_ATTR(in_intensity2_resistance, F_RF_LED, afe4403_res_table);
+static AFE440X_ATTR(in_intensity2_capacitance, F_CF_LED, afe4403_cap_table);
+
+static AFE440X_ATTR(in_intensity3_resistance, F_RF_LED1, afe4403_res_table);
+static AFE440X_ATTR(in_intensity3_capacitance, F_CF_LED1, afe4403_cap_table);
+
+static AFE440X_ATTR(in_intensity4_resistance, F_RF_LED1, afe4403_res_table);
+static AFE440X_ATTR(in_intensity4_capacitance, F_CF_LED1, afe4403_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 afe4403_read(struct afe4403_data *afe, unsigned int reg, u32 *val)
+{
+	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
+	u8 rx[3];
+	int ret;
+
+	/* Enable reading from the device */
+	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
+	if (ret)
+		return ret;
+
+	ret = spi_write_then_read(afe->spi, &reg, 1, rx, 3);
+	if (ret)
+		return ret;
+
+	*val = (rx[0] << 16) |
+		(rx[1] << 8) |
+		(rx[2]);
+
+	/* Disable reading from the device */
+	tx[3] = AFE440X_CONTROL0_WRITE;
+	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int afe4403_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct afe4403_data *afe = iio_priv(indio_dev);
+	unsigned int reg = afe4403_channel_values[chan->address];
+	unsigned int field = afe4403_channel_leds[chan->address];
+	int ret;
+
+	switch (chan->type) {
+	case IIO_INTENSITY:
+		switch (mask) {
+		case IIO_CHAN_INFO_RAW:
+			ret = afe4403_read(afe, reg, 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[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 afe4403_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct afe4403_data *afe = iio_priv(indio_dev);
+	unsigned int field = afe4403_channel_leds[chan->address];
+
+	switch (chan->type) {
+	case IIO_CURRENT:
+		switch (mask) {
+		case IIO_CHAN_INFO_RAW:
+			return regmap_field_write(afe->fields[field], val);
+		}
+		break;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info afe4403_iio_info = {
+	.attrs = &afe440x_attribute_group,
+	.read_raw = afe4403_read_raw,
+	.write_raw = afe4403_write_raw,
+};
+
+static irqreturn_t afe4403_trigger_handler(int irq, void *private)
+{
+	struct iio_poll_func *pf = private;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct afe4403_data *afe = iio_priv(indio_dev);
+	int ret, bit, i = 0;
+	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
+	u8 rx[3];
+
+	/* Enable reading from the device */
+	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
+	if (ret)
+		goto err;
+
+	for_each_set_bit(bit, indio_dev->active_scan_mask,
+			 indio_dev->masklength) {
+		ret = spi_write_then_read(afe->spi,
+					  &afe4403_channel_values[bit], 1,
+					  rx, 3);
+		if (ret)
+			goto err;
+
+		afe->buffer[i++] = (rx[0] << 16) |
+				   (rx[1] << 8) |
+				   (rx[2]);
+	}
+
+	/* Disable reading from the device */
+	tx[3] = AFE440X_CONTROL0_WRITE;
+	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
+	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 afe4403_trigger_ops = {
+};
+
+#define AFE4403_TIMING_PAIRS			\
+	{ AFE440X_LED2STC,	0x000050 },	\
+	{ AFE440X_LED2ENDC,	0x0003e7 },	\
+	{ AFE440X_LED1LEDSTC,	0x0007d0 },	\
+	{ AFE440X_LED1LEDENDC,	0x000bb7 },	\
+	{ AFE440X_ALED2STC,	0x000438 },	\
+	{ AFE440X_ALED2ENDC,	0x0007cf },	\
+	{ AFE440X_LED1STC,	0x000820 },	\
+	{ AFE440X_LED1ENDC,	0x000bb7 },	\
+	{ AFE440X_LED2LEDSTC,	0x000000 },	\
+	{ AFE440X_LED2LEDENDC,	0x0003e7 },	\
+	{ AFE440X_ALED1STC,	0x000c08 },	\
+	{ AFE440X_ALED1ENDC,	0x000f9f },	\
+	{ AFE440X_LED2CONVST,	0x0003ef },	\
+	{ AFE440X_LED2CONVEND,	0x0007cf },	\
+	{ AFE440X_ALED2CONVST,	0x0007d7 },	\
+	{ AFE440X_ALED2CONVEND,	0x000bb7 },	\
+	{ AFE440X_LED1CONVST,	0x000bbf },	\
+	{ AFE440X_LED1CONVEND,	0x009c3f },	\
+	{ AFE440X_ALED1CONVST,	0x000fa7 },	\
+	{ AFE440X_ALED1CONVEND,	0x001387 },	\
+	{ AFE440X_ADCRSTSTCT0,	0x0003e8 },	\
+	{ AFE440X_ADCRSTENDCT0,	0x0003eb },	\
+	{ AFE440X_ADCRSTSTCT1,	0x0007d0 },	\
+	{ AFE440X_ADCRSTENDCT1,	0x0007d3 },	\
+	{ AFE440X_ADCRSTSTCT2,	0x000bb8 },	\
+	{ AFE440X_ADCRSTENDCT2,	0x000bbb },	\
+	{ AFE440X_ADCRSTSTCT3,	0x000fa0 },	\
+	{ AFE440X_ADCRSTENDCT3,	0x000fa3 },	\
+	{ AFE440X_PRPCOUNT,	0x009c3f },	\
+	{ AFE440X_PDNCYCLESTC,	0x001518 },	\
+	{ AFE440X_PDNCYCLEENDC,	0x00991f }
+
+static const struct reg_sequence afe4403_reg_sequences[] = {
+	AFE4403_TIMING_PAIRS,
+	{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
+	{ AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN },
+};
+
+static const struct regmap_range afe4403_yes_ranges[] = {
+	regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
+};
+
+static const struct regmap_access_table afe4403_volatile_table = {
+	.yes_ranges = afe4403_yes_ranges,
+	.n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges),
+};
+
+static const struct regmap_config afe4403_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 24,
+
+	.max_register = AFE440X_PDNCYCLEENDC,
+	.cache_type = REGCACHE_RBTREE,
+	.volatile_table = &afe4403_volatile_table,
+};
+
+static const struct of_device_id afe4403_of_match[] = {
+	{ .compatible = "ti,afe4403", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, afe4403_of_match);
+
+static int __maybe_unused afe4403_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
+	struct afe4403_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 afe4403_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
+	struct afe4403_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(afe4403_pm_ops, afe4403_suspend, afe4403_resume);
+
+static int afe4403_probe(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev;
+	struct afe4403_data *afe;
+	int i, ret;
+
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*afe));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	afe = iio_priv(indio_dev);
+	spi_set_drvdata(spi, indio_dev);
+
+	afe->dev = &spi->dev;
+	afe->spi = spi;
+	afe->irq = spi->irq;
+
+	afe->regmap = devm_regmap_init_spi(spi, &afe4403_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,
+							 afe4403_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 err_disable_reg;
+	}
+
+	ret = regmap_multi_reg_write(afe->regmap, afe4403_reg_sequences,
+				     ARRAY_SIZE(afe4403_reg_sequences));
+	if (ret) {
+		dev_err(afe->dev, "Unable to set register defaults\n");
+		goto err_disable_reg;
+	}
+
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->dev.parent = afe->dev;
+	indio_dev->channels = afe4403_channels;
+	indio_dev->num_channels = ARRAY_SIZE(afe4403_channels);
+	indio_dev->name = AFE4403_DRIVER_NAME;
+	indio_dev->info = &afe4403_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 err_disable_reg;
+		}
+
+		iio_trigger_set_drvdata(afe->trig, indio_dev);
+
+		afe->trig->ops = &afe4403_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 err_disable_reg;
+		}
+
+		ret = devm_request_threaded_irq(afe->dev, afe->irq,
+						iio_trigger_generic_data_rdy_poll,
+						NULL, IRQF_ONESHOT,
+						AFE4403_DRIVER_NAME,
+						afe->trig);
+		if (ret) {
+			dev_err(afe->dev, "Unable to request IRQ\n");
+			goto err_trig;
+		}
+	}
+
+	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
+					 afe4403_trigger_handler, NULL);
+	if (ret) {
+		dev_err(afe->dev, "Unable to setup buffer\n");
+		goto err_trig;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		dev_err(afe->dev, "Unable to register IIO device\n");
+		goto err_buff;
+	}
+
+	return 0;
+
+err_buff:
+	iio_triggered_buffer_cleanup(indio_dev);
+err_trig:
+	if (afe->irq > 0)
+		iio_trigger_unregister(afe->trig);
+err_disable_reg:
+	regulator_disable(afe->regulator);
+
+	return ret;
+}
+
+static int afe4403_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct afe4403_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 spi_device_id afe4403_ids[] = {
+	{ "afe4403", 0 },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(spi, afe4403_ids);
+
+static struct spi_driver afe4403_spi_driver = {
+	.driver = {
+		.name = AFE4403_DRIVER_NAME,
+		.of_match_table = afe4403_of_match,
+		.pm = &afe4403_pm_ops,
+	},
+	.probe = afe4403_probe,
+	.remove = afe4403_remove,
+	.id_table = afe4403_ids,
+};
+module_spi_driver(afe4403_spi_driver);
+
+MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
+MODULE_DESCRIPTION("TI AFE4403 Heart Rate Monitor and Pulse Oximeter AFE");
+MODULE_LICENSE("GPL v2");
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");
diff --git a/drivers/iio/health/afe440x.h b/drivers/iio/health/afe440x.h
new file mode 100644
index 000000000..1a0f24704
--- /dev/null
+++ b/drivers/iio/health/afe440x.h
@@ -0,0 +1,163 @@
+/*
+ * AFE440X Heart Rate Monitors and Low-Cost Pulse Oximeters
+ *
+ * Copyright (C) 2015 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.
+ */
+
+#ifndef _AFE440X_H
+#define _AFE440X_H
+
+/* AFE440X registers */
+#define AFE440X_CONTROL0		0x00
+#define AFE440X_LED2STC			0x01
+#define AFE440X_LED2ENDC		0x02
+#define AFE440X_LED1LEDSTC		0x03
+#define AFE440X_LED1LEDENDC		0x04
+#define AFE440X_ALED2STC		0x05
+#define AFE440X_ALED2ENDC		0x06
+#define AFE440X_LED1STC			0x07
+#define AFE440X_LED1ENDC		0x08
+#define AFE440X_LED2LEDSTC		0x09
+#define AFE440X_LED2LEDENDC		0x0a
+#define AFE440X_ALED1STC		0x0b
+#define AFE440X_ALED1ENDC		0x0c
+#define AFE440X_LED2CONVST		0x0d
+#define AFE440X_LED2CONVEND		0x0e
+#define AFE440X_ALED2CONVST		0x0f
+#define AFE440X_ALED2CONVEND		0x10
+#define AFE440X_LED1CONVST		0x11
+#define AFE440X_LED1CONVEND		0x12
+#define AFE440X_ALED1CONVST		0x13
+#define AFE440X_ALED1CONVEND		0x14
+#define AFE440X_ADCRSTSTCT0		0x15
+#define AFE440X_ADCRSTENDCT0		0x16
+#define AFE440X_ADCRSTSTCT1		0x17
+#define AFE440X_ADCRSTENDCT1		0x18
+#define AFE440X_ADCRSTSTCT2		0x19
+#define AFE440X_ADCRSTENDCT2		0x1a
+#define AFE440X_ADCRSTSTCT3		0x1b
+#define AFE440X_ADCRSTENDCT3		0x1c
+#define AFE440X_PRPCOUNT		0x1d
+#define AFE440X_CONTROL1		0x1e
+#define AFE440X_LEDCNTRL		0x22
+#define AFE440X_CONTROL2		0x23
+#define AFE440X_ALARM			0x29
+#define AFE440X_LED2VAL			0x2a
+#define AFE440X_ALED2VAL		0x2b
+#define AFE440X_LED1VAL			0x2c
+#define AFE440X_ALED1VAL		0x2d
+#define AFE440X_LED2_ALED2VAL		0x2e
+#define AFE440X_LED1_ALED1VAL		0x2f
+#define AFE440X_CONTROL3		0x31
+#define AFE440X_PDNCYCLESTC		0x32
+#define AFE440X_PDNCYCLEENDC		0x33
+
+/* CONTROL0 register fields */
+#define AFE440X_CONTROL0_REG_READ	BIT(0)
+#define AFE440X_CONTROL0_TM_COUNT_RST	BIT(1)
+#define AFE440X_CONTROL0_SW_RESET	BIT(3)
+
+/* CONTROL1 register fields */
+#define AFE440X_CONTROL1_TIMEREN	BIT(8)
+
+/* TIAGAIN register fields */
+#define AFE440X_TIAGAIN_ENSEPGAIN	BIT(15)
+
+/* CONTROL2 register fields */
+#define AFE440X_CONTROL2_PDN_AFE	BIT(0)
+#define AFE440X_CONTROL2_PDN_RX		BIT(1)
+#define AFE440X_CONTROL2_DYNAMIC4	BIT(3)
+#define AFE440X_CONTROL2_DYNAMIC3	BIT(4)
+#define AFE440X_CONTROL2_DYNAMIC2	BIT(14)
+#define AFE440X_CONTROL2_DYNAMIC1	BIT(20)
+
+/* CONTROL3 register fields */
+#define AFE440X_CONTROL3_CLKDIV		GENMASK(2, 0)
+
+/* CONTROL0 values */
+#define AFE440X_CONTROL0_WRITE		0x0
+#define AFE440X_CONTROL0_READ		0x1
+
+#define AFE440X_INTENSITY_CHAN(_index, _mask)			\
+	{							\
+		.type = IIO_INTENSITY,				\
+		.channel = _index,				\
+		.address = _index,				\
+		.scan_index = _index,				\
+		.scan_type = {					\
+				.sign = 's',			\
+				.realbits = 24,			\
+				.storagebits = 32,		\
+				.endianness = IIO_CPU,		\
+		},						\
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |	\
+			_mask,					\
+		.indexed = true,				\
+	}
+
+#define AFE440X_CURRENT_CHAN(_index)				\
+	{							\
+		.type = IIO_CURRENT,				\
+		.channel = _index,				\
+		.address = _index,				\
+		.scan_index = -1,				\
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |	\
+			BIT(IIO_CHAN_INFO_SCALE),		\
+		.indexed = true,				\
+		.output = true,					\
+	}
+
+struct afe440x_val_table {
+	int integer;
+	int fract;
+};
+
+#define AFE440X_TABLE_ATTR(_name, _table)				\
+static ssize_t _name ## _show(struct device *dev,			\
+			      struct device_attribute *attr, char *buf)	\
+{									\
+	ssize_t len = 0;						\
+	int i;								\
+									\
+	for (i = 0; i < ARRAY_SIZE(_table); i++)			\
+		len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ", \
+				 _table[i].integer,			\
+				 _table[i].fract);			\
+									\
+	buf[len - 1] = '\n';						\
+									\
+	return len;							\
+}									\
+static DEVICE_ATTR_RO(_name)
+
+struct afe440x_attr {
+	struct device_attribute dev_attr;
+	unsigned int field;
+	const struct afe440x_val_table *val_table;
+	unsigned int table_size;
+};
+
+#define to_afe440x_attr(_dev_attr)				\
+	container_of(_dev_attr, struct afe440x_attr, dev_attr)
+
+#define AFE440X_ATTR(_name, _field, _table)			\
+	struct afe440x_attr afe440x_attr_##_name = {		\
+		.dev_attr = __ATTR(_name, (S_IRUGO | S_IWUSR),	\
+				   afe440x_show_register,	\
+				   afe440x_store_register),	\
+		.field = _field,				\
+		.val_table = _table,				\
+		.table_size = ARRAY_SIZE(_table),		\
+	}
+
+#endif /* _AFE440X_H */
diff --git a/drivers/iio/health/max30100.c b/drivers/iio/health/max30100.c
new file mode 100644
index 000000000..840105017
--- /dev/null
+++ b/drivers/iio/health/max30100.c
@@ -0,0 +1,515 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * max30100.c - Support for MAX30100 heart rate and pulse oximeter sensor
+ *
+ * Copyright (C) 2015, 2018
+ * Author: Matt Ranostay <matt.ranostay@konsulko.com>
+ *
+ * TODO: enable pulse length controls via device tree properties
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+
+#define MAX30100_REGMAP_NAME	"max30100_regmap"
+#define MAX30100_DRV_NAME	"max30100"
+
+#define MAX30100_REG_INT_STATUS			0x00
+#define MAX30100_REG_INT_STATUS_PWR_RDY		BIT(0)
+#define MAX30100_REG_INT_STATUS_SPO2_RDY	BIT(4)
+#define MAX30100_REG_INT_STATUS_HR_RDY		BIT(5)
+#define MAX30100_REG_INT_STATUS_FIFO_RDY	BIT(7)
+
+#define MAX30100_REG_INT_ENABLE			0x01
+#define MAX30100_REG_INT_ENABLE_SPO2_EN		BIT(0)
+#define MAX30100_REG_INT_ENABLE_HR_EN		BIT(1)
+#define MAX30100_REG_INT_ENABLE_FIFO_EN		BIT(3)
+#define MAX30100_REG_INT_ENABLE_MASK		0xf0
+#define MAX30100_REG_INT_ENABLE_MASK_SHIFT	4
+
+#define MAX30100_REG_FIFO_WR_PTR		0x02
+#define MAX30100_REG_FIFO_OVR_CTR		0x03
+#define MAX30100_REG_FIFO_RD_PTR		0x04
+#define MAX30100_REG_FIFO_DATA			0x05
+#define MAX30100_REG_FIFO_DATA_ENTRY_COUNT	16
+#define MAX30100_REG_FIFO_DATA_ENTRY_LEN	4
+
+#define MAX30100_REG_MODE_CONFIG		0x06
+#define MAX30100_REG_MODE_CONFIG_MODE_SPO2_EN	BIT(0)
+#define MAX30100_REG_MODE_CONFIG_MODE_HR_EN	BIT(1)
+#define MAX30100_REG_MODE_CONFIG_MODE_MASK	0x03
+#define MAX30100_REG_MODE_CONFIG_TEMP_EN	BIT(3)
+#define MAX30100_REG_MODE_CONFIG_PWR		BIT(7)
+
+#define MAX30100_REG_SPO2_CONFIG		0x07
+#define MAX30100_REG_SPO2_CONFIG_100HZ		BIT(2)
+#define MAX30100_REG_SPO2_CONFIG_HI_RES_EN	BIT(6)
+#define MAX30100_REG_SPO2_CONFIG_1600US		0x3
+
+#define MAX30100_REG_LED_CONFIG			0x09
+#define MAX30100_REG_LED_CONFIG_LED_MASK	0x0f
+#define MAX30100_REG_LED_CONFIG_RED_LED_SHIFT	4
+
+#define MAX30100_REG_LED_CONFIG_24MA		0x07
+#define MAX30100_REG_LED_CONFIG_50MA		0x0f
+
+#define MAX30100_REG_TEMP_INTEGER		0x16
+#define MAX30100_REG_TEMP_FRACTION		0x17
+
+struct max30100_data {
+	struct i2c_client *client;
+	struct iio_dev *indio_dev;
+	struct mutex lock;
+	struct regmap *regmap;
+
+	__be16 buffer[2]; /* 2 16-bit channels */
+};
+
+static bool max30100_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case MAX30100_REG_INT_STATUS:
+	case MAX30100_REG_MODE_CONFIG:
+	case MAX30100_REG_FIFO_WR_PTR:
+	case MAX30100_REG_FIFO_OVR_CTR:
+	case MAX30100_REG_FIFO_RD_PTR:
+	case MAX30100_REG_FIFO_DATA:
+	case MAX30100_REG_TEMP_INTEGER:
+	case MAX30100_REG_TEMP_FRACTION:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config max30100_regmap_config = {
+	.name = MAX30100_REGMAP_NAME,
+
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = MAX30100_REG_TEMP_FRACTION,
+	.cache_type = REGCACHE_FLAT,
+
+	.volatile_reg = max30100_is_volatile_reg,
+};
+
+static const unsigned int max30100_led_current_mapping[] = {
+	4400, 7600, 11000, 14200, 17400,
+	20800, 24000, 27100, 30600, 33800,
+	37000, 40200, 43600, 46800, 50000
+};
+
+static const unsigned long max30100_scan_masks[] = {0x3, 0};
+
+static const struct iio_chan_spec max30100_channels[] = {
+	{
+		.type = IIO_INTENSITY,
+		.channel2 = IIO_MOD_LIGHT_IR,
+		.modified = 1,
+
+		.scan_index = 0,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_BE,
+		},
+	},
+	{
+		.type = IIO_INTENSITY,
+		.channel2 = IIO_MOD_LIGHT_RED,
+		.modified = 1,
+
+		.scan_index = 1,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_BE,
+		},
+	},
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate =
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = -1,
+	},
+};
+
+static int max30100_set_powermode(struct max30100_data *data, bool state)
+{
+	return regmap_update_bits(data->regmap, MAX30100_REG_MODE_CONFIG,
+				  MAX30100_REG_MODE_CONFIG_PWR,
+				  state ? 0 : MAX30100_REG_MODE_CONFIG_PWR);
+}
+
+static int max30100_clear_fifo(struct max30100_data *data)
+{
+	int ret;
+
+	ret = regmap_write(data->regmap, MAX30100_REG_FIFO_WR_PTR, 0);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(data->regmap, MAX30100_REG_FIFO_OVR_CTR, 0);
+	if (ret)
+		return ret;
+
+	return regmap_write(data->regmap, MAX30100_REG_FIFO_RD_PTR, 0);
+}
+
+static int max30100_buffer_postenable(struct iio_dev *indio_dev)
+{
+	struct max30100_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = max30100_set_powermode(data, true);
+	if (ret)
+		return ret;
+
+	return max30100_clear_fifo(data);
+}
+
+static int max30100_buffer_predisable(struct iio_dev *indio_dev)
+{
+	struct max30100_data *data = iio_priv(indio_dev);
+
+	return max30100_set_powermode(data, false);
+}
+
+static const struct iio_buffer_setup_ops max30100_buffer_setup_ops = {
+	.postenable = max30100_buffer_postenable,
+	.predisable = max30100_buffer_predisable,
+};
+
+static inline int max30100_fifo_count(struct max30100_data *data)
+{
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(data->regmap, MAX30100_REG_INT_STATUS, &val);
+	if (ret)
+		return ret;
+
+	/* FIFO is almost full */
+	if (val & MAX30100_REG_INT_STATUS_FIFO_RDY)
+		return MAX30100_REG_FIFO_DATA_ENTRY_COUNT - 1;
+
+	return 0;
+}
+
+static int max30100_read_measurement(struct max30100_data *data)
+{
+	int ret;
+
+	ret = i2c_smbus_read_i2c_block_data(data->client,
+					    MAX30100_REG_FIFO_DATA,
+					    MAX30100_REG_FIFO_DATA_ENTRY_LEN,
+					    (u8 *) &data->buffer);
+
+	return (ret == MAX30100_REG_FIFO_DATA_ENTRY_LEN) ? 0 : ret;
+}
+
+static irqreturn_t max30100_interrupt_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct max30100_data *data = iio_priv(indio_dev);
+	int ret, cnt = 0;
+
+	mutex_lock(&data->lock);
+
+	while (cnt || (cnt = max30100_fifo_count(data)) > 0) {
+		ret = max30100_read_measurement(data);
+		if (ret)
+			break;
+
+		iio_push_to_buffers(data->indio_dev, data->buffer);
+		cnt--;
+	}
+
+	mutex_unlock(&data->lock);
+
+	return IRQ_HANDLED;
+}
+
+static int max30100_get_current_idx(unsigned int val, int *reg)
+{
+	int idx;
+
+	/* LED turned off */
+	if (val == 0) {
+		*reg = 0;
+		return 0;
+	}
+
+	for (idx = 0; idx < ARRAY_SIZE(max30100_led_current_mapping); idx++) {
+		if (max30100_led_current_mapping[idx] == val) {
+			*reg = idx + 1;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int max30100_led_init(struct max30100_data *data)
+{
+	struct device *dev = &data->client->dev;
+	struct device_node *np = dev->of_node;
+	unsigned int val[2];
+	int reg, ret;
+
+	ret = of_property_read_u32_array(np, "maxim,led-current-microamp",
+					(unsigned int *) &val, 2);
+	if (ret) {
+		/* Default to 24 mA RED LED, 50 mA IR LED */
+		reg = (MAX30100_REG_LED_CONFIG_24MA <<
+			MAX30100_REG_LED_CONFIG_RED_LED_SHIFT) |
+			MAX30100_REG_LED_CONFIG_50MA;
+		dev_warn(dev, "no led-current-microamp set");
+
+		return regmap_write(data->regmap, MAX30100_REG_LED_CONFIG, reg);
+	}
+
+	/* RED LED current */
+	ret = max30100_get_current_idx(val[0], &reg);
+	if (ret) {
+		dev_err(dev, "invalid RED current setting %d", val[0]);
+		return ret;
+	}
+
+	ret = regmap_update_bits(data->regmap, MAX30100_REG_LED_CONFIG,
+		MAX30100_REG_LED_CONFIG_LED_MASK <<
+		MAX30100_REG_LED_CONFIG_RED_LED_SHIFT,
+		reg << MAX30100_REG_LED_CONFIG_RED_LED_SHIFT);
+	if (ret)
+		return ret;
+
+	/* IR LED current */
+	ret = max30100_get_current_idx(val[1], &reg);
+	if (ret) {
+		dev_err(dev, "invalid IR current setting %d", val[1]);
+		return ret;
+	}
+
+	return regmap_update_bits(data->regmap, MAX30100_REG_LED_CONFIG,
+		MAX30100_REG_LED_CONFIG_LED_MASK, reg);
+}
+
+static int max30100_chip_init(struct max30100_data *data)
+{
+	int ret;
+
+	/* setup LED current settings */
+	ret = max30100_led_init(data);
+	if (ret)
+		return ret;
+
+	/* enable hi-res SPO2 readings at 100Hz */
+	ret = regmap_write(data->regmap, MAX30100_REG_SPO2_CONFIG,
+				 MAX30100_REG_SPO2_CONFIG_HI_RES_EN |
+				 MAX30100_REG_SPO2_CONFIG_100HZ);
+	if (ret)
+		return ret;
+
+	/* enable SPO2 mode */
+	ret = regmap_update_bits(data->regmap, MAX30100_REG_MODE_CONFIG,
+				 MAX30100_REG_MODE_CONFIG_MODE_MASK,
+				 MAX30100_REG_MODE_CONFIG_MODE_HR_EN |
+				 MAX30100_REG_MODE_CONFIG_MODE_SPO2_EN);
+	if (ret)
+		return ret;
+
+	/* enable FIFO interrupt */
+	return regmap_update_bits(data->regmap, MAX30100_REG_INT_ENABLE,
+				 MAX30100_REG_INT_ENABLE_MASK,
+				 MAX30100_REG_INT_ENABLE_FIFO_EN
+				 << MAX30100_REG_INT_ENABLE_MASK_SHIFT);
+}
+
+static int max30100_read_temp(struct max30100_data *data, int *val)
+{
+	int ret;
+	unsigned int reg;
+
+	ret = regmap_read(data->regmap, MAX30100_REG_TEMP_INTEGER, &reg);
+	if (ret < 0)
+		return ret;
+	*val = reg << 4;
+
+	ret = regmap_read(data->regmap, MAX30100_REG_TEMP_FRACTION, &reg);
+	if (ret < 0)
+		return ret;
+
+	*val |= reg & 0xf;
+	*val = sign_extend32(*val, 11);
+
+	return 0;
+}
+
+static int max30100_get_temp(struct max30100_data *data, int *val)
+{
+	int ret;
+
+	/* start acquisition */
+	ret = regmap_update_bits(data->regmap, MAX30100_REG_MODE_CONFIG,
+				 MAX30100_REG_MODE_CONFIG_TEMP_EN,
+				 MAX30100_REG_MODE_CONFIG_TEMP_EN);
+	if (ret)
+		return ret;
+
+	msleep(35);
+
+	return max30100_read_temp(data, val);
+}
+
+static int max30100_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
+{
+	struct max30100_data *data = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		/*
+		 * Temperature reading can only be acquired while engine
+		 * is running
+		 */
+		mutex_lock(&indio_dev->mlock);
+
+		if (!iio_buffer_enabled(indio_dev))
+			ret = -EAGAIN;
+		else {
+			ret = max30100_get_temp(data, val);
+			if (!ret)
+				ret = IIO_VAL_INT;
+
+		}
+
+		mutex_unlock(&indio_dev->mlock);
+		break;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 1;  /* 0.0625 */
+		*val2 = 16;
+		ret = IIO_VAL_FRACTIONAL;
+		break;
+	}
+
+	return ret;
+}
+
+static const struct iio_info max30100_info = {
+	.read_raw = max30100_read_raw,
+};
+
+static int max30100_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	struct max30100_data *data;
+	struct iio_buffer *buffer;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	buffer = devm_iio_kfifo_allocate(&client->dev);
+	if (!buffer)
+		return -ENOMEM;
+
+	iio_device_attach_buffer(indio_dev, buffer);
+
+	indio_dev->name = MAX30100_DRV_NAME;
+	indio_dev->channels = max30100_channels;
+	indio_dev->info = &max30100_info;
+	indio_dev->num_channels = ARRAY_SIZE(max30100_channels);
+	indio_dev->available_scan_masks = max30100_scan_masks;
+	indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE);
+	indio_dev->setup_ops = &max30100_buffer_setup_ops;
+	indio_dev->dev.parent = &client->dev;
+
+	data = iio_priv(indio_dev);
+	data->indio_dev = indio_dev;
+	data->client = client;
+
+	mutex_init(&data->lock);
+	i2c_set_clientdata(client, indio_dev);
+
+	data->regmap = devm_regmap_init_i2c(client, &max30100_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(&client->dev, "regmap initialization failed.\n");
+		return PTR_ERR(data->regmap);
+	}
+	max30100_set_powermode(data, false);
+
+	ret = max30100_chip_init(data);
+	if (ret)
+		return ret;
+
+	if (client->irq <= 0) {
+		dev_err(&client->dev, "no valid irq defined\n");
+		return -EINVAL;
+	}
+	ret = devm_request_threaded_irq(&client->dev, client->irq,
+					NULL, max30100_interrupt_handler,
+					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+					"max30100_irq", indio_dev);
+	if (ret) {
+		dev_err(&client->dev, "request irq (%d) failed\n", client->irq);
+		return ret;
+	}
+
+	return iio_device_register(indio_dev);
+}
+
+static int max30100_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct max30100_data *data = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	max30100_set_powermode(data, false);
+
+	return 0;
+}
+
+static const struct i2c_device_id max30100_id[] = {
+	{ "max30100", 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, max30100_id);
+
+static const struct of_device_id max30100_dt_ids[] = {
+	{ .compatible = "maxim,max30100" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max30100_dt_ids);
+
+static struct i2c_driver max30100_driver = {
+	.driver = {
+		.name	= MAX30100_DRV_NAME,
+		.of_match_table	= of_match_ptr(max30100_dt_ids),
+	},
+	.probe		= max30100_probe,
+	.remove		= max30100_remove,
+	.id_table	= max30100_id,
+};
+module_i2c_driver(max30100_driver);
+
+MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
+MODULE_DESCRIPTION("MAX30100 heart rate and pulse oximeter sensor");
+MODULE_LICENSE("GPL");
diff --git a/drivers/iio/health/max30102.c b/drivers/iio/health/max30102.c
new file mode 100644
index 000000000..15ccadc74
--- /dev/null
+++ b/drivers/iio/health/max30102.c
@@ -0,0 +1,645 @@
+/*
+ * max30102.c - Support for MAX30102 heart rate and pulse oximeter sensor
+ *
+ * Copyright (C) 2017 Matt Ranostay <matt@ranostay.consulting>
+ *
+ * Support for MAX30105 optical particle sensor
+ * Copyright (C) 2017 Peter Meerwald-Stadler <pmeerw@pmeerw.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * 7-bit I2C chip address: 0x57
+ * TODO: proximity power saving feature
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+
+#define MAX30102_REGMAP_NAME	"max30102_regmap"
+#define MAX30102_DRV_NAME	"max30102"
+#define MAX30102_PART_NUMBER	0x15
+
+enum max30102_chip_id {
+	max30102,
+	max30105,
+};
+
+enum max3012_led_idx {
+	MAX30102_LED_RED,
+	MAX30102_LED_IR,
+	MAX30105_LED_GREEN,
+};
+
+#define MAX30102_REG_INT_STATUS			0x00
+#define MAX30102_REG_INT_STATUS_PWR_RDY		BIT(0)
+#define MAX30102_REG_INT_STATUS_PROX_INT	BIT(4)
+#define MAX30102_REG_INT_STATUS_ALC_OVF		BIT(5)
+#define MAX30102_REG_INT_STATUS_PPG_RDY		BIT(6)
+#define MAX30102_REG_INT_STATUS_FIFO_RDY	BIT(7)
+
+#define MAX30102_REG_INT_ENABLE			0x02
+#define MAX30102_REG_INT_ENABLE_PROX_INT_EN	BIT(4)
+#define MAX30102_REG_INT_ENABLE_ALC_OVF_EN	BIT(5)
+#define MAX30102_REG_INT_ENABLE_PPG_EN		BIT(6)
+#define MAX30102_REG_INT_ENABLE_FIFO_EN		BIT(7)
+#define MAX30102_REG_INT_ENABLE_MASK		0xf0
+#define MAX30102_REG_INT_ENABLE_MASK_SHIFT	4
+
+#define MAX30102_REG_FIFO_WR_PTR		0x04
+#define MAX30102_REG_FIFO_OVR_CTR		0x05
+#define MAX30102_REG_FIFO_RD_PTR		0x06
+#define MAX30102_REG_FIFO_DATA			0x07
+#define MAX30102_REG_FIFO_DATA_BYTES		3
+
+#define MAX30102_REG_FIFO_CONFIG		0x08
+#define MAX30102_REG_FIFO_CONFIG_AVG_4SAMPLES	BIT(1)
+#define MAX30102_REG_FIFO_CONFIG_AVG_SHIFT	5
+#define MAX30102_REG_FIFO_CONFIG_AFULL		BIT(0)
+
+#define MAX30102_REG_MODE_CONFIG		0x09
+#define MAX30102_REG_MODE_CONFIG_MODE_NONE	0x00
+#define MAX30102_REG_MODE_CONFIG_MODE_HR	0x02 /* red LED */
+#define MAX30102_REG_MODE_CONFIG_MODE_HR_SPO2	0x03 /* red + IR LED */
+#define MAX30102_REG_MODE_CONFIG_MODE_MULTI	0x07 /* multi-LED mode */
+#define MAX30102_REG_MODE_CONFIG_MODE_MASK	GENMASK(2, 0)
+#define MAX30102_REG_MODE_CONFIG_PWR		BIT(7)
+
+#define MAX30102_REG_MODE_CONTROL_SLOT21	0x11 /* multi-LED control */
+#define MAX30102_REG_MODE_CONTROL_SLOT43	0x12
+#define MAX30102_REG_MODE_CONTROL_SLOT_MASK	(GENMASK(6, 4) | GENMASK(2, 0))
+#define MAX30102_REG_MODE_CONTROL_SLOT_SHIFT	4
+
+#define MAX30102_REG_SPO2_CONFIG		0x0a
+#define MAX30102_REG_SPO2_CONFIG_PULSE_411_US	0x03
+#define MAX30102_REG_SPO2_CONFIG_SR_400HZ	0x03
+#define MAX30102_REG_SPO2_CONFIG_SR_MASK	0x07
+#define MAX30102_REG_SPO2_CONFIG_SR_MASK_SHIFT	2
+#define MAX30102_REG_SPO2_CONFIG_ADC_4096_STEPS	BIT(0)
+#define MAX30102_REG_SPO2_CONFIG_ADC_MASK_SHIFT	5
+
+#define MAX30102_REG_RED_LED_CONFIG		0x0c
+#define MAX30102_REG_IR_LED_CONFIG		0x0d
+#define MAX30105_REG_GREEN_LED_CONFIG		0x0e
+
+#define MAX30102_REG_TEMP_CONFIG		0x21
+#define MAX30102_REG_TEMP_CONFIG_TEMP_EN	BIT(0)
+
+#define MAX30102_REG_TEMP_INTEGER		0x1f
+#define MAX30102_REG_TEMP_FRACTION		0x20
+
+#define MAX30102_REG_REV_ID			0xfe
+#define MAX30102_REG_PART_ID			0xff
+
+struct max30102_data {
+	struct i2c_client *client;
+	struct iio_dev *indio_dev;
+	struct mutex lock;
+	struct regmap *regmap;
+	enum max30102_chip_id chip_id;
+
+	u8 buffer[12];
+	__be32 processed_buffer[3]; /* 3 x 18-bit (padded to 32-bits) */
+};
+
+static const struct regmap_config max30102_regmap_config = {
+	.name = MAX30102_REGMAP_NAME,
+
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
+static const unsigned long max30102_scan_masks[] = {
+	BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR),
+	0
+};
+
+static const unsigned long max30105_scan_masks[] = {
+	BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR),
+	BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR) |
+		BIT(MAX30105_LED_GREEN),
+	0
+};
+
+#define MAX30102_INTENSITY_CHANNEL(_si, _mod) { \
+		.type = IIO_INTENSITY, \
+		.channel2 = _mod, \
+		.modified = 1, \
+		.scan_index = _si, \
+		.scan_type = { \
+			.sign = 'u', \
+			.shift = 8, \
+			.realbits = 18, \
+			.storagebits = 32, \
+			.endianness = IIO_BE, \
+		}, \
+	}
+
+static const struct iio_chan_spec max30102_channels[] = {
+	MAX30102_INTENSITY_CHANNEL(MAX30102_LED_RED, IIO_MOD_LIGHT_RED),
+	MAX30102_INTENSITY_CHANNEL(MAX30102_LED_IR, IIO_MOD_LIGHT_IR),
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate =
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = -1,
+	},
+};
+
+static const struct iio_chan_spec max30105_channels[] = {
+	MAX30102_INTENSITY_CHANNEL(MAX30102_LED_RED, IIO_MOD_LIGHT_RED),
+	MAX30102_INTENSITY_CHANNEL(MAX30102_LED_IR, IIO_MOD_LIGHT_IR),
+	MAX30102_INTENSITY_CHANNEL(MAX30105_LED_GREEN, IIO_MOD_LIGHT_GREEN),
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate =
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = -1,
+	},
+};
+
+static int max30102_set_power(struct max30102_data *data, bool en)
+{
+	return regmap_update_bits(data->regmap, MAX30102_REG_MODE_CONFIG,
+				  MAX30102_REG_MODE_CONFIG_PWR,
+				  en ? 0 : MAX30102_REG_MODE_CONFIG_PWR);
+}
+
+static int max30102_set_powermode(struct max30102_data *data, u8 mode, bool en)
+{
+	u8 reg = mode;
+
+	if (!en)
+		reg |= MAX30102_REG_MODE_CONFIG_PWR;
+
+	return regmap_update_bits(data->regmap, MAX30102_REG_MODE_CONFIG,
+				  MAX30102_REG_MODE_CONFIG_PWR |
+				  MAX30102_REG_MODE_CONFIG_MODE_MASK, reg);
+}
+
+#define MAX30102_MODE_CONTROL_LED_SLOTS(slot2, slot1) \
+	((slot2 << MAX30102_REG_MODE_CONTROL_SLOT_SHIFT) | slot1)
+
+static int max30102_buffer_postenable(struct iio_dev *indio_dev)
+{
+	struct max30102_data *data = iio_priv(indio_dev);
+	int ret;
+	u8 reg;
+
+	switch (*indio_dev->active_scan_mask) {
+	case BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR):
+		reg = MAX30102_REG_MODE_CONFIG_MODE_HR_SPO2;
+		break;
+	case BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR) |
+	     BIT(MAX30105_LED_GREEN):
+		ret = regmap_update_bits(data->regmap,
+					 MAX30102_REG_MODE_CONTROL_SLOT21,
+					 MAX30102_REG_MODE_CONTROL_SLOT_MASK,
+					 MAX30102_MODE_CONTROL_LED_SLOTS(2, 1));
+		if (ret)
+			return ret;
+
+		ret = regmap_update_bits(data->regmap,
+					 MAX30102_REG_MODE_CONTROL_SLOT43,
+					 MAX30102_REG_MODE_CONTROL_SLOT_MASK,
+					 MAX30102_MODE_CONTROL_LED_SLOTS(0, 3));
+		if (ret)
+			return ret;
+
+		reg = MAX30102_REG_MODE_CONFIG_MODE_MULTI;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return max30102_set_powermode(data, reg, true);
+}
+
+static int max30102_buffer_predisable(struct iio_dev *indio_dev)
+{
+	struct max30102_data *data = iio_priv(indio_dev);
+
+	return max30102_set_powermode(data, MAX30102_REG_MODE_CONFIG_MODE_NONE,
+				      false);
+}
+
+static const struct iio_buffer_setup_ops max30102_buffer_setup_ops = {
+	.postenable = max30102_buffer_postenable,
+	.predisable = max30102_buffer_predisable,
+};
+
+static inline int max30102_fifo_count(struct max30102_data *data)
+{
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(data->regmap, MAX30102_REG_INT_STATUS, &val);
+	if (ret)
+		return ret;
+
+	/* FIFO has one sample slot left */
+	if (val & MAX30102_REG_INT_STATUS_FIFO_RDY)
+		return 1;
+
+	return 0;
+}
+
+#define MAX30102_COPY_DATA(i) \
+	memcpy(&data->processed_buffer[(i)], \
+	       &buffer[(i) * MAX30102_REG_FIFO_DATA_BYTES], \
+	       MAX30102_REG_FIFO_DATA_BYTES)
+
+static int max30102_read_measurement(struct max30102_data *data,
+				     unsigned int measurements)
+{
+	int ret;
+	u8 *buffer = (u8 *) &data->buffer;
+
+	ret = i2c_smbus_read_i2c_block_data(data->client,
+					    MAX30102_REG_FIFO_DATA,
+					    measurements *
+					    MAX30102_REG_FIFO_DATA_BYTES,
+					    buffer);
+
+	switch (measurements) {
+	case 3:
+		MAX30102_COPY_DATA(2);
+	case 2: /* fall-through */
+		MAX30102_COPY_DATA(1);
+	case 1: /* fall-through */
+		MAX30102_COPY_DATA(0);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return (ret == measurements * MAX30102_REG_FIFO_DATA_BYTES) ?
+	       0 : -EINVAL;
+}
+
+static irqreturn_t max30102_interrupt_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct max30102_data *data = iio_priv(indio_dev);
+	unsigned int measurements = bitmap_weight(indio_dev->active_scan_mask,
+						  indio_dev->masklength);
+	int ret, cnt = 0;
+
+	mutex_lock(&data->lock);
+
+	while (cnt || (cnt = max30102_fifo_count(data)) > 0) {
+		ret = max30102_read_measurement(data, measurements);
+		if (ret)
+			break;
+
+		iio_push_to_buffers(data->indio_dev, data->processed_buffer);
+		cnt--;
+	}
+
+	mutex_unlock(&data->lock);
+
+	return IRQ_HANDLED;
+}
+
+static int max30102_get_current_idx(unsigned int val, int *reg)
+{
+	/* each step is 0.200 mA */
+	*reg = val / 200;
+
+	return *reg > 0xff ? -EINVAL : 0;
+}
+
+static int max30102_led_init(struct max30102_data *data)
+{
+	struct device *dev = &data->client->dev;
+	struct device_node *np = dev->of_node;
+	unsigned int val;
+	int reg, ret;
+
+	ret = of_property_read_u32(np, "maxim,red-led-current-microamp", &val);
+	if (ret) {
+		dev_info(dev, "no red-led-current-microamp set\n");
+
+		/* Default to 7 mA RED LED */
+		val = 7000;
+	}
+
+	ret = max30102_get_current_idx(val, &reg);
+	if (ret) {
+		dev_err(dev, "invalid RED LED current setting %d\n", val);
+		return ret;
+	}
+
+	ret = regmap_write(data->regmap, MAX30102_REG_RED_LED_CONFIG, reg);
+	if (ret)
+		return ret;
+
+	if (data->chip_id == max30105) {
+		ret = of_property_read_u32(np,
+			"maxim,green-led-current-microamp", &val);
+		if (ret) {
+			dev_info(dev, "no green-led-current-microamp set\n");
+
+			/* Default to 7 mA green LED */
+			val = 7000;
+		}
+
+		ret = max30102_get_current_idx(val, &reg);
+		if (ret) {
+			dev_err(dev, "invalid green LED current setting %d\n",
+				val);
+			return ret;
+		}
+
+		ret = regmap_write(data->regmap, MAX30105_REG_GREEN_LED_CONFIG,
+				   reg);
+		if (ret)
+			return ret;
+	}
+
+	ret = of_property_read_u32(np, "maxim,ir-led-current-microamp", &val);
+	if (ret) {
+		dev_info(dev, "no ir-led-current-microamp set\n");
+
+		/* Default to 7 mA IR LED */
+		val = 7000;
+	}
+
+	ret = max30102_get_current_idx(val, &reg);
+	if (ret) {
+		dev_err(dev, "invalid IR LED current setting %d\n", val);
+		return ret;
+	}
+
+	return regmap_write(data->regmap, MAX30102_REG_IR_LED_CONFIG, reg);
+}
+
+static int max30102_chip_init(struct max30102_data *data)
+{
+	int ret;
+
+	/* setup LED current settings */
+	ret = max30102_led_init(data);
+	if (ret)
+		return ret;
+
+	/* configure 18-bit HR + SpO2 readings at 400Hz */
+	ret = regmap_write(data->regmap, MAX30102_REG_SPO2_CONFIG,
+				(MAX30102_REG_SPO2_CONFIG_ADC_4096_STEPS
+				 << MAX30102_REG_SPO2_CONFIG_ADC_MASK_SHIFT) |
+				(MAX30102_REG_SPO2_CONFIG_SR_400HZ
+				 << MAX30102_REG_SPO2_CONFIG_SR_MASK_SHIFT) |
+				 MAX30102_REG_SPO2_CONFIG_PULSE_411_US);
+	if (ret)
+		return ret;
+
+	/* average 4 samples + generate FIFO interrupt */
+	ret = regmap_write(data->regmap, MAX30102_REG_FIFO_CONFIG,
+				(MAX30102_REG_FIFO_CONFIG_AVG_4SAMPLES
+				 << MAX30102_REG_FIFO_CONFIG_AVG_SHIFT) |
+				 MAX30102_REG_FIFO_CONFIG_AFULL);
+	if (ret)
+		return ret;
+
+	/* enable FIFO interrupt */
+	return regmap_update_bits(data->regmap, MAX30102_REG_INT_ENABLE,
+				 MAX30102_REG_INT_ENABLE_MASK,
+				 MAX30102_REG_INT_ENABLE_FIFO_EN);
+}
+
+static int max30102_read_temp(struct max30102_data *data, int *val)
+{
+	int ret;
+	unsigned int reg;
+
+	ret = regmap_read(data->regmap, MAX30102_REG_TEMP_INTEGER, &reg);
+	if (ret < 0)
+		return ret;
+	*val = reg << 4;
+
+	ret = regmap_read(data->regmap, MAX30102_REG_TEMP_FRACTION, &reg);
+	if (ret < 0)
+		return ret;
+
+	*val |= reg & 0xf;
+	*val = sign_extend32(*val, 11);
+
+	return 0;
+}
+
+static int max30102_get_temp(struct max30102_data *data, int *val, bool en)
+{
+	int ret;
+
+	if (en) {
+		ret = max30102_set_power(data, true);
+		if (ret)
+			return ret;
+	}
+
+	/* start acquisition */
+	ret = regmap_update_bits(data->regmap, MAX30102_REG_TEMP_CONFIG,
+				 MAX30102_REG_TEMP_CONFIG_TEMP_EN,
+				 MAX30102_REG_TEMP_CONFIG_TEMP_EN);
+	if (ret)
+		goto out;
+
+	msleep(35);
+	ret = max30102_read_temp(data, val);
+
+out:
+	if (en)
+		max30102_set_power(data, false);
+
+	return ret;
+}
+
+static int max30102_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
+{
+	struct max30102_data *data = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		/*
+		 * Temperature reading can only be acquired when not in
+		 * shutdown; leave shutdown briefly when buffer not running
+		 */
+		mutex_lock(&indio_dev->mlock);
+		if (!iio_buffer_enabled(indio_dev))
+			ret = max30102_get_temp(data, val, true);
+		else
+			ret = max30102_get_temp(data, val, false);
+		mutex_unlock(&indio_dev->mlock);
+		if (ret)
+			return ret;
+
+		ret = IIO_VAL_INT;
+		break;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 1000;  /* 62.5 */
+		*val2 = 16;
+		ret = IIO_VAL_FRACTIONAL;
+		break;
+	}
+
+	return ret;
+}
+
+static const struct iio_info max30102_info = {
+	.read_raw = max30102_read_raw,
+};
+
+static int max30102_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	struct max30102_data *data;
+	struct iio_buffer *buffer;
+	struct iio_dev *indio_dev;
+	int ret;
+	unsigned int reg;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	buffer = devm_iio_kfifo_allocate(&client->dev);
+	if (!buffer)
+		return -ENOMEM;
+
+	iio_device_attach_buffer(indio_dev, buffer);
+
+	indio_dev->name = MAX30102_DRV_NAME;
+	indio_dev->info = &max30102_info;
+	indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE);
+	indio_dev->setup_ops = &max30102_buffer_setup_ops;
+	indio_dev->dev.parent = &client->dev;
+
+	data = iio_priv(indio_dev);
+	data->indio_dev = indio_dev;
+	data->client = client;
+	data->chip_id = id->driver_data;
+
+	mutex_init(&data->lock);
+	i2c_set_clientdata(client, indio_dev);
+
+	switch (data->chip_id) {
+	case max30105:
+		indio_dev->channels = max30105_channels;
+		indio_dev->num_channels = ARRAY_SIZE(max30105_channels);
+		indio_dev->available_scan_masks = max30105_scan_masks;
+		break;
+	case max30102:
+		indio_dev->channels = max30102_channels;
+		indio_dev->num_channels = ARRAY_SIZE(max30102_channels);
+		indio_dev->available_scan_masks = max30102_scan_masks;
+		break;
+	default:
+		return -ENODEV;
+	}
+
+	data->regmap = devm_regmap_init_i2c(client, &max30102_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(&client->dev, "regmap initialization failed\n");
+		return PTR_ERR(data->regmap);
+	}
+
+	/* check part ID */
+	ret = regmap_read(data->regmap, MAX30102_REG_PART_ID, &reg);
+	if (ret)
+		return ret;
+	if (reg != MAX30102_PART_NUMBER)
+		return -ENODEV;
+
+	/* show revision ID */
+	ret = regmap_read(data->regmap, MAX30102_REG_REV_ID, &reg);
+	if (ret)
+		return ret;
+	dev_dbg(&client->dev, "max3010x revision %02x\n", reg);
+
+	/* clear mode setting, chip shutdown */
+	ret = max30102_set_powermode(data, MAX30102_REG_MODE_CONFIG_MODE_NONE,
+				     false);
+	if (ret)
+		return ret;
+
+	ret = max30102_chip_init(data);
+	if (ret)
+		return ret;
+
+	if (client->irq <= 0) {
+		dev_err(&client->dev, "no valid irq defined\n");
+		return -EINVAL;
+	}
+
+	ret = devm_request_threaded_irq(&client->dev, client->irq,
+					NULL, max30102_interrupt_handler,
+					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+					"max30102_irq", indio_dev);
+	if (ret) {
+		dev_err(&client->dev, "request irq (%d) failed\n", client->irq);
+		return ret;
+	}
+
+	return iio_device_register(indio_dev);
+}
+
+static int max30102_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct max30102_data *data = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	max30102_set_power(data, false);
+
+	return 0;
+}
+
+static const struct i2c_device_id max30102_id[] = {
+	{ "max30102", max30102 },
+	{ "max30105", max30105 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, max30102_id);
+
+static const struct of_device_id max30102_dt_ids[] = {
+	{ .compatible = "maxim,max30102" },
+	{ .compatible = "maxim,max30105" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max30102_dt_ids);
+
+static struct i2c_driver max30102_driver = {
+	.driver = {
+		.name	= MAX30102_DRV_NAME,
+		.of_match_table	= of_match_ptr(max30102_dt_ids),
+	},
+	.probe		= max30102_probe,
+	.remove		= max30102_remove,
+	.id_table	= max30102_id,
+};
+module_i2c_driver(max30102_driver);
+
+MODULE_AUTHOR("Matt Ranostay <matt@ranostay.consulting>");
+MODULE_DESCRIPTION("MAX30102 heart rate/pulse oximeter and MAX30105 particle sensor driver");
+MODULE_LICENSE("GPL");