Merge tag 'staging-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging and IIO driver updates from Greg KH:
 "Here is the big Staging and IIO driver update for 4.8-rc1.

  We ended up adding more code than removing, again, but it's not all
  that bad.  Lots of cleanups all over the staging tree, and new IIO
  drivers, full details in the shortlog.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (417 commits)
  drivers:iio:accel:mma8452: removed unwanted return statements
  drivers:iio:accel:mma8452: added cleanup provision in case of failure.
  iio: Add iio.git tree to MAINTAINERS
  iio:st_pressure: clean useless static channel initializers
  iio:st_pressure:lps22hb: temperature support
  iio:st_pressure:lps22hb: open drain support
  iio:st_pressure: temperature triggered buffering
  iio:st_pressure: document sampling gains
  iio:st_pressure: align storagebits on power of 2
  iio:st_sensors: align on storagebits boundaries
  staging:iio:lis3l02dq drop separate driver
  iio: accel: st_accel: Add lis3l02dq support
  iio: adc: add missing of_node references to iio_dev
  iio: adc: ti-ads1015: add indio_dev->dev.of_node reference
  iio: potentiometer: Fix typo in Kconfig
  iio: potentiometer: mcp4531: Add device tree binding
  iio: potentiometer: mcp4531: Add device tree binding documentation
  iio: potentiometer: mcp4531: Add support for MCP454x, MCP456x, MCP464x and MCP466x
  iio:imu:mpu6050: icm20608 initial support
  iio: adc: max1363: Add device tree binding
  ...

1 files changed, 1117 insertions, 0 deletions

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
new file mode 100644
index 000000000000..6943688e66df
--- /dev/null
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -0,0 +1,1117 @@
+/*
+ * Copyright (c) 2010 Christoph Mair <christoph.mair@gmail.com>
+ * Copyright (c) 2012 Bosch Sensortec GmbH
+ * Copyright (c) 2012 Unixphere AB
+ * Copyright (c) 2014 Intel Corporation
+ * Copyright (c) 2016 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * Driver for Bosch Sensortec BMP180 and BMP280 digital pressure sensor.
+ *
+ * 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.
+ *
+ * Datasheet:
+ * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP180-DS000-121.pdf
+ * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP280-DS001-12.pdf
+ * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME280_DS001-11.pdf
+ */
+
+#define pr_fmt(fmt) "bmp280: " fmt
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/gpio/consumer.h>
+#include <linux/regulator/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h> /* For irq_get_irq_data() */
+#include <linux/completion.h>
+#include <linux/pm_runtime.h>
+#include <linux/random.h>
+
+#include "bmp280.h"
+
+/*
+ * These enums are used for indexing into the array of calibration
+ * coefficients for BMP180.
+ */
+enum { AC1, AC2, AC3, AC4, AC5, AC6, B1, B2, MB, MC, MD };
+
+struct bmp180_calib {
+	s16 AC1;
+	s16 AC2;
+	s16 AC3;
+	u16 AC4;
+	u16 AC5;
+	u16 AC6;
+	s16 B1;
+	s16 B2;
+	s16 MB;
+	s16 MC;
+	s16 MD;
+};
+
+struct bmp280_data {
+	struct device *dev;
+	struct mutex lock;
+	struct regmap *regmap;
+	struct completion done;
+	bool use_eoc;
+	const struct bmp280_chip_info *chip_info;
+	struct bmp180_calib calib;
+	struct regulator *vddd;
+	struct regulator *vdda;
+	unsigned int start_up_time; /* in milliseconds */
+
+	/* log of base 2 of oversampling rate */
+	u8 oversampling_press;
+	u8 oversampling_temp;
+	u8 oversampling_humid;
+
+	/*
+	 * Carryover value from temperature conversion, used in pressure
+	 * calculation.
+	 */
+	s32 t_fine;
+};
+
+struct bmp280_chip_info {
+	const int *oversampling_temp_avail;
+	int num_oversampling_temp_avail;
+
+	const int *oversampling_press_avail;
+	int num_oversampling_press_avail;
+
+	const int *oversampling_humid_avail;
+	int num_oversampling_humid_avail;
+
+	int (*chip_config)(struct bmp280_data *);
+	int (*read_temp)(struct bmp280_data *, int *);
+	int (*read_press)(struct bmp280_data *, int *, int *);
+	int (*read_humid)(struct bmp280_data *, int *, int *);
+};
+
+/*
+ * These enums are used for indexing into the array of compensation
+ * parameters for BMP280.
+ */
+enum { T1, T2, T3 };
+enum { P1, P2, P3, P4, P5, P6, P7, P8, P9 };
+
+static const struct iio_chan_spec bmp280_channels[] = {
+	{
+		.type = IIO_PRESSURE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+	},
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+	},
+	{
+		.type = IIO_HUMIDITYRELATIVE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+	},
+};
+
+/*
+ * Returns humidity in percent, resolution is 0.01 percent. Output value of
+ * "47445" represents 47445/1024 = 46.333 %RH.
+ *
+ * Taken from BME280 datasheet, Section 4.2.3, "Compensation formula".
+ */
+
+static u32 bmp280_compensate_humidity(struct bmp280_data *data,
+				      s32 adc_humidity)
+{
+	struct device *dev = data->dev;
+	unsigned int H1, H3, tmp;
+	int H2, H4, H5, H6, ret, var;
+
+	ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &H1);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H1 comp value\n");
+		return ret;
+	}
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &tmp, 2);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H2 comp value\n");
+		return ret;
+	}
+	H2 = sign_extend32(le16_to_cpu(tmp), 15);
+
+	ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &H3);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H3 comp value\n");
+		return ret;
+	}
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &tmp, 2);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H4 comp value\n");
+		return ret;
+	}
+	H4 = sign_extend32(((be16_to_cpu(tmp) >> 4) & 0xff0) |
+			  (be16_to_cpu(tmp) & 0xf), 11);
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &tmp, 2);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H5 comp value\n");
+		return ret;
+	}
+	H5 = sign_extend32(((le16_to_cpu(tmp) >> 4) & 0xfff), 11);
+
+	ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H6 comp value\n");
+		return ret;
+	}
+	H6 = sign_extend32(tmp, 7);
+
+	var = ((s32)data->t_fine) - 76800;
+	var = ((((adc_humidity << 14) - (H4 << 20) - (H5 * var)) + 16384) >> 15)
+		* (((((((var * H6) >> 10) * (((var * H3) >> 11) + 32768)) >> 10)
+		+ 2097152) * H2 + 8192) >> 14);
+	var -= ((((var >> 15) * (var >> 15)) >> 7) * H1) >> 4;
+
+	return var >> 12;
+};
+
+/*
+ * Returns temperature in DegC, resolution is 0.01 DegC.  Output value of
+ * "5123" equals 51.23 DegC.  t_fine carries fine temperature as global
+ * value.
+ *
+ * Taken from datasheet, Section 3.11.3, "Compensation formula".
+ */
+static s32 bmp280_compensate_temp(struct bmp280_data *data,
+				  s32 adc_temp)
+{
+	int ret;
+	s32 var1, var2;
+	__le16 buf[BMP280_COMP_TEMP_REG_COUNT / 2];
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
+			       buf, BMP280_COMP_TEMP_REG_COUNT);
+	if (ret < 0) {
+		dev_err(data->dev,
+			"failed to read temperature calibration parameters\n");
+		return ret;
+	}
+
+	/*
+	 * The double casts are necessary because le16_to_cpu returns an
+	 * unsigned 16-bit value.  Casting that value directly to a
+	 * signed 32-bit will not do proper sign extension.
+	 *
+	 * Conversely, T1 and P1 are unsigned values, so they can be
+	 * cast straight to the larger type.
+	 */
+	var1 = (((adc_temp >> 3) - ((s32)le16_to_cpu(buf[T1]) << 1)) *
+		((s32)(s16)le16_to_cpu(buf[T2]))) >> 11;
+	var2 = (((((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1]))) *
+		  ((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1])))) >> 12) *
+		((s32)(s16)le16_to_cpu(buf[T3]))) >> 14;
+	data->t_fine = var1 + var2;
+
+	return (data->t_fine * 5 + 128) >> 8;
+}
+
+/*
+ * Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24
+ * integer bits and 8 fractional bits).  Output value of "24674867"
+ * represents 24674867/256 = 96386.2 Pa = 963.862 hPa
+ *
+ * Taken from datasheet, Section 3.11.3, "Compensation formula".
+ */
+static u32 bmp280_compensate_press(struct bmp280_data *data,
+				   s32 adc_press)
+{
+	int ret;
+	s64 var1, var2, p;
+	__le16 buf[BMP280_COMP_PRESS_REG_COUNT / 2];
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START,
+			       buf, BMP280_COMP_PRESS_REG_COUNT);
+	if (ret < 0) {
+		dev_err(data->dev,
+			"failed to read pressure calibration parameters\n");
+		return ret;
+	}
+
+	var1 = ((s64)data->t_fine) - 128000;
+	var2 = var1 * var1 * (s64)(s16)le16_to_cpu(buf[P6]);
+	var2 += (var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17;
+	var2 += ((s64)(s16)le16_to_cpu(buf[P4])) << 35;
+	var1 = ((var1 * var1 * (s64)(s16)le16_to_cpu(buf[P3])) >> 8) +
+		((var1 * (s64)(s16)le16_to_cpu(buf[P2])) << 12);
+	var1 = ((((s64)1) << 47) + var1) * ((s64)le16_to_cpu(buf[P1])) >> 33;
+
+	if (var1 == 0)
+		return 0;
+
+	p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125;
+	p = div64_s64(p, var1);
+	var1 = (((s64)(s16)le16_to_cpu(buf[P9])) * (p >> 13) * (p >> 13)) >> 25;
+	var2 = (((s64)(s16)le16_to_cpu(buf[P8])) * p) >> 19;
+	p = ((p + var1 + var2) >> 8) + (((s64)(s16)le16_to_cpu(buf[P7])) << 4);
+
+	return (u32)p;
+}
+
+static int bmp280_read_temp(struct bmp280_data *data,
+			    int *val)
+{
+	int ret;
+	__be32 tmp = 0;
+	s32 adc_temp, comp_temp;
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB,
+			       (u8 *) &tmp, 3);
+	if (ret < 0) {
+		dev_err(data->dev, "failed to read temperature\n");
+		return ret;
+	}
+
+	adc_temp = be32_to_cpu(tmp) >> 12;
+	comp_temp = bmp280_compensate_temp(data, adc_temp);
+
+	/*
+	 * val might be NULL if we're called by the read_press routine,
+	 * who only cares about the carry over t_fine value.
+	 */
+	if (val) {
+		*val = comp_temp * 10;
+		return IIO_VAL_INT;
+	}
+
+	return 0;
+}
+
+static int bmp280_read_press(struct bmp280_data *data,
+			     int *val, int *val2)
+{
+	int ret;
+	__be32 tmp = 0;
+	s32 adc_press;
+	u32 comp_press;
+
+	/* Read and compensate temperature so we get a reading of t_fine. */
+	ret = bmp280_read_temp(data, NULL);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB,
+			       (u8 *) &tmp, 3);
+	if (ret < 0) {
+		dev_err(data->dev, "failed to read pressure\n");
+		return ret;
+	}
+
+	adc_press = be32_to_cpu(tmp) >> 12;
+	comp_press = bmp280_compensate_press(data, adc_press);
+
+	*val = comp_press;
+	*val2 = 256000;
+
+	return IIO_VAL_FRACTIONAL;
+}
+
+static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
+{
+	int ret;
+	__be16 tmp = 0;
+	s32 adc_humidity;
+	u32 comp_humidity;
+
+	/* Read and compensate temperature so we get a reading of t_fine. */
+	ret = bmp280_read_temp(data, NULL);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB,
+			       (u8 *) &tmp, 2);
+	if (ret < 0) {
+		dev_err(data->dev, "failed to read humidity\n");
+		return ret;
+	}
+
+	adc_humidity = be16_to_cpu(tmp);
+	comp_humidity = bmp280_compensate_humidity(data, adc_humidity);
+
+	*val = comp_humidity;
+	*val2 = 1024;
+
+	return IIO_VAL_FRACTIONAL;
+}
+
+static int bmp280_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	int ret;
+	struct bmp280_data *data = iio_priv(indio_dev);
+
+	pm_runtime_get_sync(data->dev);
+	mutex_lock(&data->lock);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_PROCESSED:
+		switch (chan->type) {
+		case IIO_HUMIDITYRELATIVE:
+			ret = data->chip_info->read_humid(data, val, val2);
+			break;
+		case IIO_PRESSURE:
+			ret = data->chip_info->read_press(data, val, val2);
+			break;
+		case IIO_TEMP:
+			ret = data->chip_info->read_temp(data, val);
+			break;
+		default:
+			ret = -EINVAL;
+			break;
+		}
+		break;
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		switch (chan->type) {
+		case IIO_HUMIDITYRELATIVE:
+			*val = 1 << data->oversampling_humid;
+			ret = IIO_VAL_INT;
+			break;
+		case IIO_PRESSURE:
+			*val = 1 << data->oversampling_press;
+			ret = IIO_VAL_INT;
+			break;
+		case IIO_TEMP:
+			*val = 1 << data->oversampling_temp;
+			ret = IIO_VAL_INT;
+			break;
+		default:
+			ret = -EINVAL;
+			break;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	mutex_unlock(&data->lock);
+	pm_runtime_mark_last_busy(data->dev);
+	pm_runtime_put_autosuspend(data->dev);
+
+	return ret;
+}
+
+static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data,
+					       int val)
+{
+	int i;
+	const int *avail = data->chip_info->oversampling_humid_avail;
+	const int n = data->chip_info->num_oversampling_humid_avail;
+
+	for (i = 0; i < n; i++) {
+		if (avail[i] == val) {
+			data->oversampling_humid = ilog2(val);
+
+			return data->chip_info->chip_config(data);
+		}
+	}
+	return -EINVAL;
+}
+
+static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
+					       int val)
+{
+	int i;
+	const int *avail = data->chip_info->oversampling_temp_avail;
+	const int n = data->chip_info->num_oversampling_temp_avail;
+
+	for (i = 0; i < n; i++) {
+		if (avail[i] == val) {
+			data->oversampling_temp = ilog2(val);
+
+			return data->chip_info->chip_config(data);
+		}
+	}
+	return -EINVAL;
+}
+
+static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data,
+					       int val)
+{
+	int i;
+	const int *avail = data->chip_info->oversampling_press_avail;
+	const int n = data->chip_info->num_oversampling_press_avail;
+
+	for (i = 0; i < n; i++) {
+		if (avail[i] == val) {
+			data->oversampling_press = ilog2(val);
+
+			return data->chip_info->chip_config(data);
+		}
+	}
+	return -EINVAL;
+}
+
+static int bmp280_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val, int val2, long mask)
+{
+	int ret = 0;
+	struct bmp280_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		pm_runtime_get_sync(data->dev);
+		mutex_lock(&data->lock);
+		switch (chan->type) {
+		case IIO_HUMIDITYRELATIVE:
+			ret = bmp280_write_oversampling_ratio_humid(data, val);
+			break;
+		case IIO_PRESSURE:
+			ret = bmp280_write_oversampling_ratio_press(data, val);
+			break;
+		case IIO_TEMP:
+			ret = bmp280_write_oversampling_ratio_temp(data, val);
+			break;
+		default:
+			ret = -EINVAL;
+			break;
+		}
+		mutex_unlock(&data->lock);
+		pm_runtime_mark_last_busy(data->dev);
+		pm_runtime_put_autosuspend(data->dev);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return ret;
+}
+
+static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n)
+{
+	size_t len = 0;
+	int i;
+
+	for (i = 0; i < n; i++)
+		len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]);
+
+	buf[len - 1] = '\n';
+
+	return len;
+}
+
+static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
+
+	return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail,
+				 data->chip_info->num_oversampling_temp_avail);
+}
+
+static ssize_t bmp280_show_press_oversampling_avail(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
+
+	return bmp280_show_avail(buf, data->chip_info->oversampling_press_avail,
+				 data->chip_info->num_oversampling_press_avail);
+}
+
+static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available,
+	S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0);
+
+static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available,
+	S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0);
+
+static struct attribute *bmp280_attributes[] = {
+	&iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr,
+	&iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group bmp280_attrs_group = {
+	.attrs = bmp280_attributes,
+};
+
+static const struct iio_info bmp280_info = {
+	.driver_module = THIS_MODULE,
+	.read_raw = &bmp280_read_raw,
+	.write_raw = &bmp280_write_raw,
+	.attrs = &bmp280_attrs_group,
+};
+
+static int bmp280_chip_config(struct bmp280_data *data)
+{
+	int ret;
+	u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) |
+		  BMP280_OSRS_PRESS_X(data->oversampling_press + 1);
+
+	ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_MEAS,
+				 BMP280_OSRS_TEMP_MASK |
+				 BMP280_OSRS_PRESS_MASK |
+				 BMP280_MODE_MASK,
+				 osrs | BMP280_MODE_NORMAL);
+	if (ret < 0) {
+		dev_err(data->dev,
+			"failed to write ctrl_meas register\n");
+		return ret;
+	}
+
+	ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG,
+				 BMP280_FILTER_MASK,
+				 BMP280_FILTER_4X);
+	if (ret < 0) {
+		dev_err(data->dev,
+			"failed to write config register\n");
+		return ret;
+	}
+
+	return ret;
+}
+
+static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 };
+
+static const struct bmp280_chip_info bmp280_chip_info = {
+	.oversampling_temp_avail = bmp280_oversampling_avail,
+	.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
+
+	.oversampling_press_avail = bmp280_oversampling_avail,
+	.num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
+
+	.chip_config = bmp280_chip_config,
+	.read_temp = bmp280_read_temp,
+	.read_press = bmp280_read_press,
+};
+
+static int bme280_chip_config(struct bmp280_data *data)
+{
+	int ret = bmp280_chip_config(data);
+	u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
+
+	if (ret < 0)
+		return ret;
+
+	return regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY,
+				  BMP280_OSRS_HUMIDITY_MASK, osrs);
+}
+
+static const struct bmp280_chip_info bme280_chip_info = {
+	.oversampling_temp_avail = bmp280_oversampling_avail,
+	.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
+
+	.oversampling_press_avail = bmp280_oversampling_avail,
+	.num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
+
+	.oversampling_humid_avail = bmp280_oversampling_avail,
+	.num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail),
+
+	.chip_config = bme280_chip_config,
+	.read_temp = bmp280_read_temp,
+	.read_press = bmp280_read_press,
+	.read_humid = bmp280_read_humid,
+};
+
+static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
+{
+	int ret;
+	const int conversion_time_max[] = { 4500, 7500, 13500, 25500 };
+	unsigned int delay_us;
+	unsigned int ctrl;
+
+	if (data->use_eoc)
+		init_completion(&data->done);
+
+	ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas);
+	if (ret)
+		return ret;
+
+	if (data->use_eoc) {
+		/*
+		 * If we have a completion interrupt, use it, wait up to
+		 * 100ms. The longest conversion time listed is 76.5 ms for
+		 * advanced resolution mode.
+		 */
+		ret = wait_for_completion_timeout(&data->done,
+						  1 + msecs_to_jiffies(100));
+		if (!ret)
+			dev_err(data->dev, "timeout waiting for completion\n");
+	} else {
+		if (ctrl_meas == BMP180_MEAS_TEMP)
+			delay_us = 4500;
+		else
+			delay_us =
+				conversion_time_max[data->oversampling_press];
+
+		usleep_range(delay_us, delay_us + 1000);
+	}
+
+	ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl);
+	if (ret)
+		return ret;
+
+	/* The value of this bit reset to "0" after conversion is complete */
+	if (ctrl & BMP180_MEAS_SCO)
+		return -EIO;
+
+	return 0;
+}
+
+static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
+{
+	int ret;
+	__be16 tmp = 0;
+
+	ret = bmp180_measure(data, BMP180_MEAS_TEMP);
+	if (ret)
+		return ret;
+
+	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2);
+	if (ret)
+		return ret;
+
+	*val = be16_to_cpu(tmp);
+
+	return 0;
+}
+
+static int bmp180_read_calib(struct bmp280_data *data,
+			     struct bmp180_calib *calib)
+{
+	int ret;
+	int i;
+	__be16 buf[BMP180_REG_CALIB_COUNT / 2];
+
+	ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
+			       sizeof(buf));
+
+	if (ret < 0)
+		return ret;
+
+	/* None of the words has the value 0 or 0xFFFF */
+	for (i = 0; i < ARRAY_SIZE(buf); i++) {
+		if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff))
+			return -EIO;
+	}
+
+	/* Toss the calibration data into the entropy pool */
+	add_device_randomness(buf, sizeof(buf));
+
+	calib->AC1 = be16_to_cpu(buf[AC1]);
+	calib->AC2 = be16_to_cpu(buf[AC2]);
+	calib->AC3 = be16_to_cpu(buf[AC3]);
+	calib->AC4 = be16_to_cpu(buf[AC4]);
+	calib->AC5 = be16_to_cpu(buf[AC5]);
+	calib->AC6 = be16_to_cpu(buf[AC6]);
+	calib->B1 = be16_to_cpu(buf[B1]);
+	calib->B2 = be16_to_cpu(buf[B2]);
+	calib->MB = be16_to_cpu(buf[MB]);
+	calib->MC = be16_to_cpu(buf[MC]);
+	calib->MD = be16_to_cpu(buf[MD]);
+
+	return 0;
+}
+
+/*
+ * Returns temperature in DegC, resolution is 0.1 DegC.
+ * t_fine carries fine temperature as global value.
+ *
+ * Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
+ */
+static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp)
+{
+	s32 x1, x2;
+	struct bmp180_calib *calib = &data->calib;
+
+	x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15;
+	x2 = (calib->MC << 11) / (x1 + calib->MD);
+	data->t_fine = x1 + x2;
+
+	return (data->t_fine + 8) >> 4;
+}
+
+static int bmp180_read_temp(struct bmp280_data *data, int *val)
+{
+	int ret;
+	s32 adc_temp, comp_temp;
+
+	ret = bmp180_read_adc_temp(data, &adc_temp);
+	if (ret)
+		return ret;
+
+	comp_temp = bmp180_compensate_temp(data, adc_temp);
+
+	/*
+	 * val might be NULL if we're called by the read_press routine,
+	 * who only cares about the carry over t_fine value.
+	 */
+	if (val) {
+		*val = comp_temp * 100;
+		return IIO_VAL_INT;
+	}
+
+	return 0;
+}
+
+static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
+{
+	int ret;
+	__be32 tmp = 0;
+	u8 oss = data->oversampling_press;
+
+	ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss));
+	if (ret)
+		return ret;
+
+	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3);
+	if (ret)
+		return ret;
+
+	*val = (be32_to_cpu(tmp) >> 8) >> (8 - oss);
+
+	return 0;
+}
+
+/*
+ * Returns pressure in Pa, resolution is 1 Pa.
+ *
+ * Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
+ */
+static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press)
+{
+	s32 x1, x2, x3, p;
+	s32 b3, b6;
+	u32 b4, b7;
+	s32 oss = data->oversampling_press;
+	struct bmp180_calib *calib = &data->calib;
+
+	b6 = data->t_fine - 4000;
+	x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11;
+	x2 = calib->AC2 * b6 >> 11;
+	x3 = x1 + x2;
+	b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4;
+	x1 = calib->AC3 * b6 >> 13;
+	x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16;
+	x3 = (x1 + x2 + 2) >> 2;
+	b4 = calib->AC4 * (u32)(x3 + 32768) >> 15;
+	b7 = ((u32)adc_press - b3) * (50000 >> oss);
+	if (b7 < 0x80000000)
+		p = (b7 * 2) / b4;
+	else
+		p = (b7 / b4) * 2;
+
+	x1 = (p >> 8) * (p >> 8);
+	x1 = (x1 * 3038) >> 16;
+	x2 = (-7357 * p) >> 16;
+
+	return p + ((x1 + x2 + 3791) >> 4);
+}
+
+static int bmp180_read_press(struct bmp280_data *data,
+			     int *val, int *val2)
+{
+	int ret;
+	s32 adc_press;
+	u32 comp_press;
+
+	/* Read and compensate temperature so we get a reading of t_fine. */
+	ret = bmp180_read_temp(data, NULL);
+	if (ret)
+		return ret;
+
+	ret = bmp180_read_adc_press(data, &adc_press);
+	if (ret)
+		return ret;
+
+	comp_press = bmp180_compensate_press(data, adc_press);
+
+	*val = comp_press;
+	*val2 = 1000;
+
+	return IIO_VAL_FRACTIONAL;
+}
+
+static int bmp180_chip_config(struct bmp280_data *data)
+{
+	return 0;
+}
+
+static const int bmp180_oversampling_temp_avail[] = { 1 };
+static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 };
+
+static const struct bmp280_chip_info bmp180_chip_info = {
+	.oversampling_temp_avail = bmp180_oversampling_temp_avail,
+	.num_oversampling_temp_avail =
+		ARRAY_SIZE(bmp180_oversampling_temp_avail),
+
+	.oversampling_press_avail = bmp180_oversampling_press_avail,
+	.num_oversampling_press_avail =
+		ARRAY_SIZE(bmp180_oversampling_press_avail),
+
+	.chip_config = bmp180_chip_config,
+	.read_temp = bmp180_read_temp,
+	.read_press = bmp180_read_press,
+};
+
+static irqreturn_t bmp085_eoc_irq(int irq, void *d)
+{
+	struct bmp280_data *data = d;
+
+	complete(&data->done);
+
+	return IRQ_HANDLED;
+}
+
+static int bmp085_fetch_eoc_irq(struct device *dev,
+				const char *name,
+				int irq,
+				struct bmp280_data *data)
+{
+	unsigned long irq_trig;
+	int ret;
+
+	irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
+	if (irq_trig != IRQF_TRIGGER_RISING) {
+		dev_err(dev, "non-rising trigger given for EOC interrupt, "
+			"trying to enforce it\n");
+		irq_trig = IRQF_TRIGGER_RISING;
+	}
+	ret = devm_request_threaded_irq(dev,
+			irq,
+			bmp085_eoc_irq,
+			NULL,
+			irq_trig,
+			name,
+			data);
+	if (ret) {
+		/* Bail out without IRQ but keep the driver in place */
+		dev_err(dev, "unable to request DRDY IRQ\n");
+		return 0;
+	}
+
+	data->use_eoc = true;
+	return 0;
+}
+
+int bmp280_common_probe(struct device *dev,
+			struct regmap *regmap,
+			unsigned int chip,
+			const char *name,
+			int irq)
+{
+	int ret;
+	struct iio_dev *indio_dev;
+	struct bmp280_data *data;
+	unsigned int chip_id;
+	struct gpio_desc *gpiod;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	mutex_init(&data->lock);
+	data->dev = dev;
+
+	indio_dev->dev.parent = dev;
+	indio_dev->name = name;
+	indio_dev->channels = bmp280_channels;
+	indio_dev->info = &bmp280_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	switch (chip) {
+	case BMP180_CHIP_ID:
+		indio_dev->num_channels = 2;
+		data->chip_info = &bmp180_chip_info;
+		data->oversampling_press = ilog2(8);
+		data->oversampling_temp = ilog2(1);
+		data->start_up_time = 10;
+		break;
+	case BMP280_CHIP_ID:
+		indio_dev->num_channels = 2;
+		data->chip_info = &bmp280_chip_info;
+		data->oversampling_press = ilog2(16);
+		data->oversampling_temp = ilog2(2);
+		data->start_up_time = 2;
+		break;
+	case BME280_CHIP_ID:
+		indio_dev->num_channels = 3;
+		data->chip_info = &bme280_chip_info;
+		data->oversampling_press = ilog2(16);
+		data->oversampling_humid = ilog2(16);
+		data->oversampling_temp = ilog2(2);
+		data->start_up_time = 2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* Bring up regulators */
+	data->vddd = devm_regulator_get(dev, "vddd");
+	if (IS_ERR(data->vddd)) {
+		dev_err(dev, "failed to get VDDD regulator\n");
+		return PTR_ERR(data->vddd);
+	}
+	ret = regulator_enable(data->vddd);
+	if (ret) {
+		dev_err(dev, "failed to enable VDDD regulator\n");
+		return ret;
+	}
+	data->vdda = devm_regulator_get(dev, "vdda");
+	if (IS_ERR(data->vdda)) {
+		dev_err(dev, "failed to get VDDA regulator\n");
+		ret = PTR_ERR(data->vddd);
+		goto out_disable_vddd;
+	}
+	ret = regulator_enable(data->vdda);
+	if (ret) {
+		dev_err(dev, "failed to enable VDDA regulator\n");
+		goto out_disable_vddd;
+	}
+	/* Wait to make sure we started up properly */
+	mdelay(data->start_up_time);
+
+	/* Bring chip out of reset if there is an assigned GPIO line */
+	gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	/* Deassert the signal */
+	if (!IS_ERR(gpiod)) {
+		dev_info(dev, "release reset\n");
+		gpiod_set_value(gpiod, 0);
+	}
+
+	data->regmap = regmap;
+	ret = regmap_read(regmap, BMP280_REG_ID, &chip_id);
+	if (ret < 0)
+		goto out_disable_vdda;
+	if (chip_id != chip) {
+		dev_err(dev, "bad chip id: expected %x got %x\n",
+			chip, chip_id);
+		ret = -EINVAL;
+		goto out_disable_vdda;
+	}
+
+	ret = data->chip_info->chip_config(data);
+	if (ret < 0)
+		goto out_disable_vdda;
+
+	dev_set_drvdata(dev, indio_dev);
+
+	/*
+	 * The BMP085 and BMP180 has calibration in an E2PROM, read it out
+	 * at probe time. It will not change.
+	 */
+	if (chip_id  == BMP180_CHIP_ID) {
+		ret = bmp180_read_calib(data, &data->calib);
+		if (ret < 0) {
+			dev_err(data->dev,
+				"failed to read calibration coefficients\n");
+			goto out_disable_vdda;
+		}
+	}
+
+	/*
+	 * Attempt to grab an optional EOC IRQ - only the BMP085 has this
+	 * however as it happens, the BMP085 shares the chip ID of BMP180
+	 * so we look for an IRQ if we have that.
+	 */
+	if (irq > 0 || (chip_id  == BMP180_CHIP_ID)) {
+		ret = bmp085_fetch_eoc_irq(dev, name, irq, data);
+		if (ret)
+			goto out_disable_vdda;
+	}
+
+	/* Enable runtime PM */
+	pm_runtime_get_noresume(dev);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	/*
+	 * Set autosuspend to two orders of magnitude larger than the
+	 * start-up time.
+	 */
+	pm_runtime_set_autosuspend_delay(dev, data->start_up_time *100);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_put(dev);
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto out_runtime_pm_disable;
+
+
+	return 0;
+
+out_runtime_pm_disable:
+	pm_runtime_get_sync(data->dev);
+	pm_runtime_put_noidle(data->dev);
+	pm_runtime_disable(data->dev);
+out_disable_vdda:
+	regulator_disable(data->vdda);
+out_disable_vddd:
+	regulator_disable(data->vddd);
+	return ret;
+}
+EXPORT_SYMBOL(bmp280_common_probe);
+
+int bmp280_common_remove(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bmp280_data *data = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	pm_runtime_get_sync(data->dev);
+	pm_runtime_put_noidle(data->dev);
+	pm_runtime_disable(data->dev);
+	regulator_disable(data->vdda);
+	regulator_disable(data->vddd);
+	return 0;
+}
+EXPORT_SYMBOL(bmp280_common_remove);
+
+#ifdef CONFIG_PM
+static int bmp280_runtime_suspend(struct device *dev)
+{
+	struct bmp280_data *data = dev_get_drvdata(dev);
+	int ret;
+
+	ret = regulator_disable(data->vdda);
+	if (ret)
+		return ret;
+	return regulator_disable(data->vddd);
+}
+
+static int bmp280_runtime_resume(struct device *dev)
+{
+	struct bmp280_data *data = dev_get_drvdata(dev);
+	int ret;
+
+	ret = regulator_enable(data->vddd);
+	if (ret)
+		return ret;
+	ret = regulator_enable(data->vdda);
+	if (ret)
+		return ret;
+	msleep(data->start_up_time);
+	return data->chip_info->chip_config(data);
+}
+#endif /* CONFIG_PM */
+
+const struct dev_pm_ops bmp280_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
+	SET_RUNTIME_PM_OPS(bmp280_runtime_suspend,
+			   bmp280_runtime_resume, NULL)
+};
+EXPORT_SYMBOL(bmp280_dev_pm_ops);
+
+MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
+MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor");
+MODULE_LICENSE("GPL v2");