[PATCH 2/5] staging:iio:hmc5843: Split hmc5843.c to multiple files

[Josef Gajdusek <atx@atalax.net>]

This patch splits hmc5843.c to multiple files - the interface-agnostic
hmc5843_core.c, i2c specific hmc5843_i2c.c and header file hmc5843.h. This is
another step to add support of SPI-enabled hmc5983.

Signed-off-by: Josef Gajdusek <atx@atx.name>
---
 drivers/staging/iio/magnetometer/Kconfig        |  16 +-
 drivers/staging/iio/magnetometer/Makefile       |   3 +-
 drivers/staging/iio/magnetometer/hmc5843.c      | 701 ------------------------
 drivers/staging/iio/magnetometer/hmc5843.h      |  75 +++
 drivers/staging/iio/magnetometer/hmc5843_core.c | 598 ++++++++++++++++++++
 drivers/staging/iio/magnetometer/hmc5843_i2c.c  | 106 ++++
 6 files changed, 793 insertions(+), 706 deletions(-)
 delete mode 100644 drivers/staging/iio/magnetometer/hmc5843.c
 create mode 100644 drivers/staging/iio/magnetometer/hmc5843.h
 create mode 100644 drivers/staging/iio/magnetometer/hmc5843_core.c
 create mode 100644 drivers/staging/iio/magnetometer/hmc5843_i2c.c

diff --git a/drivers/staging/iio/magnetometer/Kconfig b/drivers/staging/iio/magnetometer/Kconfig
index ad88d61..28c2612 100644
--- a/drivers/staging/iio/magnetometer/Kconfig
+++ b/drivers/staging/iio/magnetometer/Kconfig
@@ -5,15 +5,23 @@ menu "Magnetometer sensors"
 
 config SENSORS_HMC5843
 	tristate "Honeywell HMC5843/5883/5883L 3-Axis Magnetometer"
-	depends on I2C
+	depends on (I2C || SPI_MASTER)
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
-	select REGMAP_I2C
+	select SENSORS_HMC5843_I2C if (I2C)
 	help
 	  Say Y here to add support for the Honeywell HMC5843, HMC5883 and
 	  HMC5883L 3-Axis Magnetometer (digital compass).
 
-	  To compile this driver as a module, choose M here: the module
-	  will be called hmc5843.
+	  This driver can also be compiled as a set of modules.
+	  If so, these modules will be created:
+	  - hmc5843_core (core functions)
+	  - hmc5843_i2c (support for HMC5843, HMC5883 and HMC5883L)
+
+config SENSORS_HMC5843_I2C
+	tristate
+	depends on I2C
+	depends on SENSORS_HMC5843
+	select REGMAP_I2C
 
 endmenu
diff --git a/drivers/staging/iio/magnetometer/Makefile b/drivers/staging/iio/magnetometer/Makefile
index f9bfb2e..65baf1c 100644
--- a/drivers/staging/iio/magnetometer/Makefile
+++ b/drivers/staging/iio/magnetometer/Makefile
@@ -2,4 +2,5 @@
 # Makefile for industrial I/O Magnetometer sensors
 #
 
-obj-$(CONFIG_SENSORS_HMC5843)	+= hmc5843.o
+obj-$(CONFIG_SENSORS_HMC5843)		+= hmc5843_core.o
+obj-$(CONFIG_SENSORS_HMC5843_I2C)	+= hmc5843_i2c.o
diff --git a/drivers/staging/iio/magnetometer/hmc5843.c b/drivers/staging/iio/magnetometer/hmc5843.c
deleted file mode 100644
index cc12308..0000000
--- a/drivers/staging/iio/magnetometer/hmc5843.c
+++ /dev/null
@@ -1,701 +0,0 @@
-/*  Copyright (C) 2010 Texas Instruments
-    Author: Shubhrajyoti Datta <shubhrajyoti@ti.com>
-    Acknowledgement: Jonathan Cameron <jic23@kernel.org> for valuable inputs.
-
-    Support for HMC5883 and HMC5883L by Peter Meerwald <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.
-
-    You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
-#include <linux/module.h>
-#include <linux/i2c.h>
-#include <linux/regmap.h>
-#include <linux/iio/iio.h>
-#include <linux/iio/sysfs.h>
-#include <linux/iio/trigger_consumer.h>
-#include <linux/iio/buffer.h>
-#include <linux/iio/triggered_buffer.h>
-#include <linux/delay.h>
-
-#define HMC5843_CONFIG_REG_A			0x00
-#define HMC5843_CONFIG_REG_B			0x01
-#define HMC5843_MODE_REG			0x02
-#define HMC5843_DATA_OUT_MSB_REGS		0x03
-#define HMC5843_STATUS_REG			0x09
-#define HMC5843_ID_REG				0x0a
-#define HMC5843_ID_END				0x0c
-
-enum hmc5843_ids {
-	HMC5843_ID,
-	HMC5883_ID,
-	HMC5883L_ID,
-};
-
-/*
- * Range gain settings in (+-)Ga
- * Beware: HMC5843 and HMC5883 have different recommended sensor field
- * ranges; default corresponds to +-1.0 Ga and +-1.3 Ga, respectively
- */
-#define HMC5843_RANGE_GAIN_OFFSET		0x05
-#define HMC5843_RANGE_GAIN_DEFAULT		0x01
-#define HMC5843_RANGE_GAINS			8
-#define HMC5843_RANGE_GAIN_MASK		0xe0
-
-/* Device status */
-#define HMC5843_DATA_READY			0x01
-#define HMC5843_DATA_OUTPUT_LOCK		0x02
-
-/* Mode register configuration */
-#define HMC5843_MODE_CONVERSION_CONTINUOUS	0x00
-#define HMC5843_MODE_CONVERSION_SINGLE		0x01
-#define HMC5843_MODE_IDLE			0x02
-#define HMC5843_MODE_SLEEP			0x03
-#define HMC5843_MODE_MASK			0x03
-
-/*
- * HMC5843: Minimum data output rate
- * HMC5883: Typical data output rate
- */
-#define HMC5843_RATE_OFFSET			0x02
-#define HMC5843_RATE_DEFAULT			0x04
-#define HMC5843_RATES				7
-#define HMC5843_RATE_MASK		0x1c
-
-/* Device measurement configuration */
-#define HMC5843_MEAS_CONF_NORMAL		0x00
-#define HMC5843_MEAS_CONF_POSITIVE_BIAS		0x01
-#define HMC5843_MEAS_CONF_NEGATIVE_BIAS		0x02
-#define HMC5843_MEAS_CONF_MASK			0x03
-
-/* Scaling factors: 10000000/Gain */
-static const int hmc5843_regval_to_nanoscale[HMC5843_RANGE_GAINS] = {
-	6173, 7692, 10309, 12821, 18868, 21739, 25641, 35714
-};
-
-static const int hmc5883_regval_to_nanoscale[HMC5843_RANGE_GAINS] = {
-	7812, 9766, 13021, 16287, 24096, 27701, 32573, 45662
-};
-
-static const int hmc5883l_regval_to_nanoscale[HMC5843_RANGE_GAINS] = {
-	7299, 9174, 12195, 15152, 22727, 25641, 30303, 43478
-};
-
-/*
- * 
- * Value	| HMC5843		| HMC5883/HMC5883L
- *		| Data output rate (Hz)	| Data output rate (Hz)
- * 0		| 0.5			| 0.75
- * 1		| 1			| 1.5
- * 2		| 2			| 3
- * 3		| 5			| 7.5
- * 4		| 10 (default)		| 15
- * 5		| 20			| 30
- * 6		| 50			| 75
- * 7		| Not used		| Not used
- */
-static const int hmc5843_regval_to_samp_freq[7][2] = {
-	{0, 500000}, {1, 0}, {2, 0}, {5, 0}, {10, 0}, {20, 0}, {50, 0}
-};
-
-static const int hmc5883_regval_to_samp_freq[7][2] = {
-	{0, 750000}, {1, 500000}, {3, 0}, {7, 500000}, {15, 0}, {30, 0},
-	{75, 0}
-};
-
-/* Describe chip variants */
-struct hmc5843_chip_info {
-	const struct iio_chan_spec *channels;
-	const int (*regval_to_samp_freq)[2];
-	const int *regval_to_nanoscale;
-};
-
-/* Each client has this additional data */
-struct hmc5843_data {
-	struct i2c_client *client;
-	struct mutex lock;
-	struct regmap *regmap;
-	const struct hmc5843_chip_info *variant;
-	__be16 buffer[8]; /* 3x 16-bit channels + padding + 64-bit timestamp */
-};
-
-/* The lower two bits contain the current conversion mode */
-static s32 hmc5843_set_mode(struct hmc5843_data *data, u8 operating_mode)
-{
-	int ret;
-
-	mutex_lock(&data->lock);
-	ret = regmap_update_bits(data->regmap, HMC5843_MODE_REG,
-			HMC5843_MODE_MASK, operating_mode);
-	mutex_unlock(&data->lock);
-
-	return ret;
-}
-
-static int hmc5843_wait_measurement(struct hmc5843_data *data)
-{
-	int tries = 150;
-	int val;
-	int ret;
-
-	while (tries-- > 0) {
-		ret = regmap_read(data->regmap, HMC5843_STATUS_REG, &val);
-		if (ret < 0)
-			return ret;
-		if (val & HMC5843_DATA_READY)
-			break;
-		msleep(20);
-	}
-
-	if (tries < 0) {
-		dev_err(&data->client->dev, "data not ready\n");
-		return -EIO;
-	}
-
-	return 0;
-}
-
-/* Return the measurement value from the specified channel */
-static int hmc5843_read_measurement(struct hmc5843_data *data,
-				    int idx, int *val)
-{
-	__be16 values[3];
-	int ret;
-
-	mutex_lock(&data->lock);
-	ret = hmc5843_wait_measurement(data);
-	if (ret < 0) {
-		mutex_unlock(&data->lock);
-		return ret;
-	}
-	ret = regmap_bulk_read(data->regmap, HMC5843_DATA_OUT_MSB_REGS,
-			values, sizeof(values));
-	mutex_unlock(&data->lock);
-	if (ret < 0)
-		return ret;
-
-	*val = sign_extend32(be16_to_cpu(values[idx]), 15);
-	return IIO_VAL_INT;
-}
-
-/*
- * API for setting the measurement configuration to
- * Normal, Positive bias and Negative bias
- *
- * 
- * 0 - Normal measurement configuration (default): In normal measurement
- *     configuration the device follows normal measurement flow. Pins BP
- *     and BN are left floating and high impedance.
- *
- * 1 - Positive bias configuration: In positive bias configuration, a
- *     positive current is forced across the resistive load on pins BP
- *     and BN.
- *
- * 2 - Negative bias configuration. In negative bias configuration, a
- *     negative current is forced across the resistive load on pins BP
- *     and BN.
- *
- */
-static int hmc5843_set_meas_conf(struct hmc5843_data *data, u8 meas_conf)
-{
-	int ret;
-
-	mutex_lock(&data->lock);
-	ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_A,
-			HMC5843_MEAS_CONF_MASK, meas_conf);
-	mutex_unlock(&data->lock);
-
-	return ret;
-}
-
-static ssize_t hmc5843_show_measurement_configuration(struct device *dev,
-						struct device_attribute *attr,
-						char *buf)
-{
-	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
-	int val;
-	int ret;
-
-	ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_A, &val);
-	if (ret)
-		return ret;
-	val &= HMC5843_MEAS_CONF_MASK;
-
-	return sprintf(buf, "%d\n", val);
-}
-
-static ssize_t hmc5843_set_measurement_configuration(struct device *dev,
-						struct device_attribute *attr,
-						const char *buf,
-						size_t count)
-{
-	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
-	unsigned long meas_conf = 0;
-	int ret;
-
-	ret = kstrtoul(buf, 10, &meas_conf);
-	if (ret)
-		return ret;
-	if (meas_conf >= HMC5843_MEAS_CONF_MASK)
-		return -EINVAL;
-
-	ret = hmc5843_set_meas_conf(data, meas_conf);
-
-	return (ret < 0) ? ret : count;
-}
-
-static IIO_DEVICE_ATTR(meas_conf,
-			S_IWUSR | S_IRUGO,
-			hmc5843_show_measurement_configuration,
-			hmc5843_set_measurement_configuration,
-			0);
-
-static ssize_t hmc5843_show_samp_freq_avail(struct device *dev,
-				struct device_attribute *attr, char *buf)
-{
-	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
-	size_t len = 0;
-	int i;
-
-	for (i = 0; i < HMC5843_RATES; i++)
-		len += scnprintf(buf + len, PAGE_SIZE - len,
-			"%d.%d ", data->variant->regval_to_samp_freq[i][0],
-			data->variant->regval_to_samp_freq[i][1]);
-
-	/* replace trailing space by newline */
-	buf[len - 1] = '\n';
-
-	return len;
-}
-
-static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(hmc5843_show_samp_freq_avail);
-
-static int hmc5843_set_samp_freq(struct hmc5843_data *data, u8 rate)
-{
-	int ret;
-
-	mutex_lock(&data->lock);
-	ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_A,
-			HMC5843_RATE_MASK, rate << HMC5843_RATE_OFFSET);
-	mutex_unlock(&data->lock);
-
-	return ret;
-}
-
-static int hmc5843_get_samp_freq_index(struct hmc5843_data *data,
-				   int val, int val2)
-{
-	int i;
-
-	for (i = 0; i < HMC5843_RATES; i++)
-		if (val == data->variant->regval_to_samp_freq[i][0] &&
-			val2 == data->variant->regval_to_samp_freq[i][1])
-			return i;
-
-	return -EINVAL;
-}
-
-static int hmc5843_set_range_gain(struct hmc5843_data *data, u8 range)
-{
-	int ret;
-
-	mutex_lock(&data->lock);
-	ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_B,
-			HMC5843_RANGE_GAIN_MASK,
-			range << HMC5843_RANGE_GAIN_OFFSET);
-	mutex_unlock(&data->lock);
-
-	return ret;
-}
-
-static ssize_t hmc5843_show_scale_avail(struct device *dev,
-				struct device_attribute *attr, char *buf)
-{
-	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
-
-	size_t len = 0;
-	int i;
-
-	for (i = 0; i < HMC5843_RANGE_GAINS; i++)
-		len += scnprintf(buf + len, PAGE_SIZE - len,
-			"0.%09d ", data->variant->regval_to_nanoscale[i]);
-
-	/* replace trailing space by newline */
-	buf[len - 1] = '\n';
-
-	return len;
-}
-
-static IIO_DEVICE_ATTR(scale_available, S_IRUGO,
-	hmc5843_show_scale_avail, NULL, 0);
-
-static int hmc5843_get_scale_index(struct hmc5843_data *data, int val, int val2)
-{
-	int i;
-
-	if (val != 0)
-		return -EINVAL;
-
-	for (i = 0; i < HMC5843_RANGE_GAINS; i++)
-		if (val2 == data->variant->regval_to_nanoscale[i])
-			return i;
-
-	return -EINVAL;
-}
-
-static int hmc5843_read_raw(struct iio_dev *indio_dev,
-			    struct iio_chan_spec const *chan,
-			    int *val, int *val2, long mask)
-{
-	struct hmc5843_data *data = iio_priv(indio_dev);
-	int rval;
-	int ret;
-
-	switch (mask) {
-	case IIO_CHAN_INFO_RAW:
-		return hmc5843_read_measurement(data, chan->scan_index, val);
-	case IIO_CHAN_INFO_SCALE:
-		ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_B, &rval);
-		if (ret < 0)
-			return ret;
-		*val = 0;
-		*val2 = data->variant->regval_to_nanoscale[rval >> HMC5843_RANGE_GAIN_OFFSET];
-		return IIO_VAL_INT_PLUS_NANO;
-	case IIO_CHAN_INFO_SAMP_FREQ:
-		ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_A, &rval);
-		if (ret < 0)
-			return ret;
-		rval &= HMC5843_RATE_MASK;
-		*val = data->variant->regval_to_samp_freq[rval][0];
-		*val2 = data->variant->regval_to_samp_freq[rval][1];
-		return IIO_VAL_INT_PLUS_MICRO;
-	}
-	return -EINVAL;
-}
-
-static int hmc5843_write_raw(struct iio_dev *indio_dev,
-			     struct iio_chan_spec const *chan,
-			     int val, int val2, long mask)
-{
-	struct hmc5843_data *data = iio_priv(indio_dev);
-	int rate, range;
-
-	switch (mask) {
-	case IIO_CHAN_INFO_SAMP_FREQ:
-		rate = hmc5843_get_samp_freq_index(data, val, val2);
-		if (rate < 0)
-			return -EINVAL;
-
-		return hmc5843_set_samp_freq(data, rate);
-	case IIO_CHAN_INFO_SCALE:
-		range = hmc5843_get_scale_index(data, val, val2);
-		if (range < 0)
-			return -EINVAL;
-
-		return hmc5843_set_range_gain(data, range);
-	default:
-		return -EINVAL;
-	}
-}
-
-static int hmc5843_write_raw_get_fmt(struct iio_dev *indio_dev,
-			       struct iio_chan_spec const *chan, long mask)
-{
-	switch (mask) {
-	case IIO_CHAN_INFO_SAMP_FREQ:
-		return IIO_VAL_INT_PLUS_MICRO;
-	case IIO_CHAN_INFO_SCALE:
-		return IIO_VAL_INT_PLUS_NANO;
-	default:
-		return -EINVAL;
-	}
-}
-
-static irqreturn_t hmc5843_trigger_handler(int irq, void *p)
-{
-	struct iio_poll_func *pf = p;
-	struct iio_dev *indio_dev = pf->indio_dev;
-	struct hmc5843_data *data = iio_priv(indio_dev);
-	int ret;
-
-	mutex_lock(&data->lock);
-	ret = hmc5843_wait_measurement(data);
-	if (ret < 0) {
-		mutex_unlock(&data->lock);
-		goto done;
-	}
-
-	ret = regmap_bulk_read(data->regmap, HMC5843_DATA_OUT_MSB_REGS,
-			data->buffer, 3 * sizeof(__be16));
-
-	mutex_unlock(&data->lock);
-	if (ret < 0)
-		goto done;
-
-	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
-		iio_get_time_ns());
-
-done:
-	iio_trigger_notify_done(indio_dev->trig);
-
-	return IRQ_HANDLED;
-}
-
-#define HMC5843_CHANNEL(axis, idx)					\
-	{								\
-		.type = IIO_MAGN,					\
-		.modified = 1,						\
-		.channel2 = IIO_MOD_##axis,				\
-		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
-		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |	\
-			BIT(IIO_CHAN_INFO_SAMP_FREQ),			\
-		.scan_index = idx,					\
-		.scan_type = {						\
-			.sign = 's',					\
-			.realbits = 16,					\
-			.storagebits = 16,				\
-			.endianness = IIO_BE,				\
-		},							\
-	}
-
-static const struct iio_chan_spec hmc5843_channels[] = {
-	HMC5843_CHANNEL(X, 0),
-	HMC5843_CHANNEL(Y, 1),
-	HMC5843_CHANNEL(Z, 2),
-	IIO_CHAN_SOFT_TIMESTAMP(3),
-};
-
-/* Beware: Y and Z are exchanged on HMC5883 */
-static const struct iio_chan_spec hmc5883_channels[] = {
-	HMC5843_CHANNEL(X, 0),
-	HMC5843_CHANNEL(Z, 1),
-	HMC5843_CHANNEL(Y, 2),
-	IIO_CHAN_SOFT_TIMESTAMP(3),
-};
-
-static struct attribute *hmc5843_attributes[] = {
-	&iio_dev_attr_meas_conf.dev_attr.attr,
-	&iio_dev_attr_scale_available.dev_attr.attr,
-	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
-	NULL
-};
-
-static const struct attribute_group hmc5843_group = {
-	.attrs = hmc5843_attributes,
-};
-
-static const struct hmc5843_chip_info hmc5843_chip_info_tbl[] = {
-	[HMC5843_ID] = {
-		.channels = hmc5843_channels,
-		.regval_to_samp_freq = hmc5843_regval_to_samp_freq,
-		.regval_to_nanoscale = hmc5843_regval_to_nanoscale,
-	},
-	[HMC5883_ID] = {
-		.channels = hmc5883_channels,
-		.regval_to_samp_freq = hmc5883_regval_to_samp_freq,
-		.regval_to_nanoscale = hmc5883_regval_to_nanoscale,
-	},
-	[HMC5883L_ID] = {
-		.channels = hmc5883_channels,
-		.regval_to_samp_freq = hmc5883_regval_to_samp_freq,
-		.regval_to_nanoscale = hmc5883l_regval_to_nanoscale,
-	},
-};
-
-static int hmc5843_init(struct hmc5843_data *data)
-{
-	int ret;
-	u8 id[3];
-
-	ret = regmap_bulk_read(data->regmap, HMC5843_ID_REG,
-			id, ARRAY_SIZE(id));
-	if (ret < 0)
-		return ret;
-	if (id[0] != 'H' || id[1] != '4' || id[2] != '3') {
-		dev_err(&data->client->dev, "no HMC5843/5883/5883L sensor\n");
-		return -ENODEV;
-	}
-
-	ret = hmc5843_set_meas_conf(data, HMC5843_MEAS_CONF_NORMAL);
-	if (ret < 0)
-		return ret;
-	ret = hmc5843_set_samp_freq(data, HMC5843_RATE_DEFAULT);
-	if (ret < 0)
-		return ret;
-	ret = hmc5843_set_range_gain(data, HMC5843_RANGE_GAIN_DEFAULT);
-	if (ret < 0)
-		return ret;
-	return hmc5843_set_mode(data, HMC5843_MODE_CONVERSION_CONTINUOUS);
-}
-
-static const struct iio_info hmc5843_info = {
-	.attrs = &hmc5843_group,
-	.read_raw = &hmc5843_read_raw,
-	.write_raw = &hmc5843_write_raw,
-	.write_raw_get_fmt = &hmc5843_write_raw_get_fmt,
-	.driver_module = THIS_MODULE,
-};
-
-static const unsigned long hmc5843_scan_masks[] = {0x7, 0};
-
-static const struct regmap_range hmc5843_readable_ranges[] = {
-		regmap_reg_range(0, HMC5843_ID_END),
-};
-
-static struct regmap_access_table hmc5843_readable_table = {
-		.yes_ranges = hmc5843_readable_ranges,
-		.n_yes_ranges = ARRAY_SIZE(hmc5843_readable_ranges),
-};
-
-static const struct regmap_range hmc5843_writable_ranges[] = {
-		regmap_reg_range(0, HMC5843_MODE_REG),
-};
-
-static struct regmap_access_table hmc5843_writable_table = {
-		.yes_ranges = hmc5843_writable_ranges,
-		.n_yes_ranges = ARRAY_SIZE(hmc5843_writable_ranges),
-};
-
-static const struct regmap_range hmc5843_volatile_ranges[] = {
-		regmap_reg_range(HMC5843_DATA_OUT_MSB_REGS, HMC5843_STATUS_REG),
-};
-
-static struct regmap_access_table hmc5843_volatile_table = {
-		.yes_ranges = hmc5843_volatile_ranges,
-		.n_yes_ranges = ARRAY_SIZE(hmc5843_volatile_ranges),
-};
-
-static struct regmap_config hmc5843_regmap_config = {
-		.reg_bits = 8,
-		.val_bits = 8,
-
-		.rd_table = &hmc5843_readable_table,
-		.wr_table = &hmc5843_writable_table,
-		.volatile_table = &hmc5843_volatile_table,
-
-		.cache_type = REGCACHE_RBTREE,
-};
-
-static int hmc5843_probe(struct i2c_client *client,
-			 const struct i2c_device_id *id)
-{
-	struct hmc5843_data *data;
-	struct iio_dev *indio_dev;
-	int ret;
-
-	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
-	if (indio_dev == NULL)
-		return -ENOMEM;
-
-	/* default settings at probe */
-	data = iio_priv(indio_dev);
-	data->client = client;
-	data->variant = &hmc5843_chip_info_tbl[id->driver_data];
-	data->regmap = devm_regmap_init_i2c(client, &hmc5843_regmap_config);
-	mutex_init(&data->lock);
-
-	i2c_set_clientdata(client, indio_dev);
-	indio_dev->info = &hmc5843_info;
-	indio_dev->name = id->name;
-	indio_dev->dev.parent = &client->dev;
-	indio_dev->modes = INDIO_DIRECT_MODE;
-	indio_dev->channels = data->variant->channels;
-	indio_dev->num_channels = 4;
-	indio_dev->available_scan_masks = hmc5843_scan_masks;
-
-	ret = hmc5843_init(data);
-	if (ret < 0)
-		return ret;
-
-	ret = iio_triggered_buffer_setup(indio_dev, NULL,
-		hmc5843_trigger_handler, NULL);
-	if (ret < 0)
-		return ret;
-
-	ret = iio_device_register(indio_dev);
-	if (ret < 0)
-		goto buffer_cleanup;
-
-	return 0;
-
-buffer_cleanup:
-	iio_triggered_buffer_cleanup(indio_dev);
-	return ret;
-}
-
-static int hmc5843_remove(struct i2c_client *client)
-{
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-
-	/*  sleep mode to save power */
-	hmc5843_set_mode(iio_priv(indio_dev), HMC5843_MODE_SLEEP);
-
-	iio_device_unregister(indio_dev);
-	iio_triggered_buffer_cleanup(indio_dev);
-
-	return 0;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int hmc5843_suspend(struct device *dev)
-{
-	struct hmc5843_data *data = iio_priv(i2c_get_clientdata(
-		to_i2c_client(dev)));
-
-	return hmc5843_set_mode(data, HMC5843_MODE_SLEEP);
-}
-
-static int hmc5843_resume(struct device *dev)
-{
-	struct hmc5843_data *data = iio_priv(i2c_get_clientdata(
-		to_i2c_client(dev)));
-
-	return hmc5843_set_mode(data, HMC5843_MODE_CONVERSION_CONTINUOUS);
-}
-
-static SIMPLE_DEV_PM_OPS(hmc5843_pm_ops, hmc5843_suspend, hmc5843_resume);
-#define HMC5843_PM_OPS (&hmc5843_pm_ops)
-#else
-#define HMC5843_PM_OPS NULL
-#endif
-
-static const struct i2c_device_id hmc5843_id[] = {
-	{ "hmc5843", HMC5843_ID },
-	{ "hmc5883", HMC5883_ID },
-	{ "hmc5883l", HMC5883L_ID },
-	{ }
-};
-MODULE_DEVICE_TABLE(i2c, hmc5843_id);
-
-static const struct of_device_id hmc5843_of_match[] = {
-	{ .compatible = "honeywell,hmc5843" },
-	{}
-};
-MODULE_DEVICE_TABLE(of, hmc5843_of_match);
-
-static struct i2c_driver hmc5843_driver = {
-	.driver = {
-		.name	= "hmc5843",
-		.pm	= HMC5843_PM_OPS,
-		.of_match_table = hmc5843_of_match,
-	},
-	.id_table	= hmc5843_id,
-	.probe		= hmc5843_probe,
-	.remove		= hmc5843_remove,
-};
-module_i2c_driver(hmc5843_driver);
-
-MODULE_AUTHOR("Shubhrajyoti Datta <shubhrajyoti@ti.com>");
-MODULE_DESCRIPTION("HMC5843/5883/5883L driver");
-MODULE_LICENSE("GPL");
diff --git a/drivers/staging/iio/magnetometer/hmc5843.h b/drivers/staging/iio/magnetometer/hmc5843.h
new file mode 100644
index 0000000..4e3cce3
--- /dev/null
+++ b/drivers/staging/iio/magnetometer/hmc5843.h
@@ -0,0 +1,75 @@
+/*
+ * Header file for hmc5843 driver
+ *
+ * Split from hmc5843.c
+ * Copyright (C) Josef Gajdusek <atx@atx.name>
+ *
+ * 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.
+ *
+ * */
+
+
+#ifndef HMC5843_CORE_H
+#define HMC5843_CORE_H
+
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+
+#define HMC5843_CONFIG_REG_A			0x00
+#define HMC5843_CONFIG_REG_B			0x01
+#define HMC5843_MODE_REG			0x02
+#define HMC5843_DATA_OUT_MSB_REGS		0x03
+#define HMC5843_STATUS_REG			0x09
+#define HMC5843_ID_REG				0x0a
+#define HMC5843_ID_END				0x0c
+
+enum hmc5843_ids {
+	HMC5843_ID,
+	HMC5883_ID,
+	HMC5883L_ID,
+};
+
+struct hmc5843_data {
+	struct device *dev;
+	struct mutex lock;
+	struct regmap *regmap;
+	const struct hmc5843_chip_info *variant;
+	__be16 buffer[8]; /* 3x 16-bit channels + padding + 64-bit timestamp */
+};
+
+int hmc5843_common_probe(struct iio_dev *indio_dev, enum hmc5843_ids id);
+int hmc5843_common_remove(struct iio_dev *indio_dev);
+
+int hmc5843_common_suspend(struct iio_dev *indio_dev);
+int hmc5843_common_resume(struct iio_dev *indio_dev);
+
+static const struct regmap_range hmc5843_readable_ranges[] = {
+		regmap_reg_range(0, HMC5843_ID_END),
+};
+
+static struct regmap_access_table hmc5843_readable_table = {
+		.yes_ranges = hmc5843_readable_ranges,
+		.n_yes_ranges = ARRAY_SIZE(hmc5843_readable_ranges),
+};
+
+static const struct regmap_range hmc5843_writable_ranges[] = {
+		regmap_reg_range(0, HMC5843_MODE_REG),
+};
+
+static struct regmap_access_table hmc5843_writable_table = {
+		.yes_ranges = hmc5843_writable_ranges,
+		.n_yes_ranges = ARRAY_SIZE(hmc5843_writable_ranges),
+};
+
+static const struct regmap_range hmc5843_volatile_ranges[] = {
+		regmap_reg_range(HMC5843_DATA_OUT_MSB_REGS, HMC5843_STATUS_REG),
+};
+
+static struct regmap_access_table hmc5843_volatile_table = {
+		.yes_ranges = hmc5843_volatile_ranges,
+		.n_yes_ranges = ARRAY_SIZE(hmc5843_volatile_ranges),
+};
+
+#endif /* HMC5843_CORE_H */
diff --git a/drivers/staging/iio/magnetometer/hmc5843_core.c b/drivers/staging/iio/magnetometer/hmc5843_core.c
new file mode 100644
index 0000000..4ad309b
--- /dev/null
+++ b/drivers/staging/iio/magnetometer/hmc5843_core.c
@@ -0,0 +1,598 @@
+/*  Copyright (C) 2010 Texas Instruments
+    Author: Shubhrajyoti Datta <shubhrajyoti@ti.com>
+    Acknowledgement: Jonathan Cameron <jic23@kernel.org> for valuable inputs.
+
+    Support for HMC5883 and HMC5883L by Peter Meerwald <pmeerw@pmeerw.net>.
+
+    Split to multiple files by Josef Gajdusek <atx@atx.name> - 2014
+
+    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.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/delay.h>
+
+#include "hmc5843.h"
+
+/*
+ * Range gain settings in (+-)Ga
+ * Beware: HMC5843 and HMC5883 have different recommended sensor field
+ * ranges; default corresponds to +-1.0 Ga and +-1.3 Ga, respectively
+ */
+#define HMC5843_RANGE_GAIN_OFFSET		0x05
+#define HMC5843_RANGE_GAIN_DEFAULT		0x01
+#define HMC5843_RANGE_GAINS			8
+#define HMC5843_RANGE_GAIN_MASK		0xe0
+
+/* Device status */
+#define HMC5843_DATA_READY			0x01
+#define HMC5843_DATA_OUTPUT_LOCK		0x02
+
+/* Mode register configuration */
+#define HMC5843_MODE_CONVERSION_CONTINUOUS	0x00
+#define HMC5843_MODE_CONVERSION_SINGLE		0x01
+#define HMC5843_MODE_IDLE			0x02
+#define HMC5843_MODE_SLEEP			0x03
+#define HMC5843_MODE_MASK			0x03
+
+/*
+ * HMC5843: Minimum data output rate
+ * HMC5883: Typical data output rate
+ */
+#define HMC5843_RATE_OFFSET			0x02
+#define HMC5843_RATE_DEFAULT			0x04
+#define HMC5843_RATES				7
+#define HMC5843_RATE_MASK		0x1c
+
+/* Device measurement configuration */
+#define HMC5843_MEAS_CONF_NORMAL		0x00
+#define HMC5843_MEAS_CONF_POSITIVE_BIAS		0x01
+#define HMC5843_MEAS_CONF_NEGATIVE_BIAS		0x02
+#define HMC5843_MEAS_CONF_MASK			0x03
+
+/* Scaling factors: 10000000/Gain */
+static const int hmc5843_regval_to_nanoscale[HMC5843_RANGE_GAINS] = {
+	6173, 7692, 10309, 12821, 18868, 21739, 25641, 35714
+};
+
+static const int hmc5883_regval_to_nanoscale[HMC5843_RANGE_GAINS] = {
+	7812, 9766, 13021, 16287, 24096, 27701, 32573, 45662
+};
+
+static const int hmc5883l_regval_to_nanoscale[HMC5843_RANGE_GAINS] = {
+	7299, 9174, 12195, 15152, 22727, 25641, 30303, 43478
+};
+
+/*
+ * 
+ * Value	| HMC5843		| HMC5883/HMC5883L
+ *		| Data output rate (Hz)	| Data output rate (Hz)
+ * 0		| 0.5			| 0.75
+ * 1		| 1			| 1.5
+ * 2		| 2			| 3
+ * 3		| 5			| 7.5
+ * 4		| 10 (default)		| 15
+ * 5		| 20			| 30
+ * 6		| 50			| 75
+ * 7		| Not used		| Not used
+ */
+static const int hmc5843_regval_to_samp_freq[7][2] = {
+	{0, 500000}, {1, 0}, {2, 0}, {5, 0}, {10, 0}, {20, 0}, {50, 0}
+};
+
+static const int hmc5883_regval_to_samp_freq[7][2] = {
+	{0, 750000}, {1, 500000}, {3, 0}, {7, 500000}, {15, 0}, {30, 0},
+	{75, 0}
+};
+
+/* Describe chip variants */
+struct hmc5843_chip_info {
+	const struct iio_chan_spec *channels;
+	const int (*regval_to_samp_freq)[2];
+	const int *regval_to_nanoscale;
+};
+
+/* The lower two bits contain the current conversion mode */
+static s32 hmc5843_set_mode(struct hmc5843_data *data, u8 operating_mode)
+{
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_update_bits(data->regmap, HMC5843_MODE_REG,
+			HMC5843_MODE_MASK, operating_mode);
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int hmc5843_wait_measurement(struct hmc5843_data *data)
+{
+	int tries = 150;
+	int val;
+	int ret;
+
+	while (tries-- > 0) {
+		ret = regmap_read(data->regmap, HMC5843_STATUS_REG, &val);
+		if (ret < 0)
+			return ret;
+		if (val & HMC5843_DATA_READY)
+			break;
+		msleep(20);
+	}
+
+	if (tries < 0) {
+		dev_err(data->dev, "data not ready\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/* Return the measurement value from the specified channel */
+static int hmc5843_read_measurement(struct hmc5843_data *data,
+				    int idx, int *val)
+{
+	__be16 values[3];
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = hmc5843_wait_measurement(data);
+	if (ret < 0) {
+		mutex_unlock(&data->lock);
+		return ret;
+	}
+	ret = regmap_bulk_read(data->regmap, HMC5843_DATA_OUT_MSB_REGS,
+			values, sizeof(values));
+	mutex_unlock(&data->lock);
+	if (ret < 0)
+		return ret;
+
+	*val = sign_extend32(be16_to_cpu(values[idx]), 15);
+	return IIO_VAL_INT;
+}
+
+/*
+ * API for setting the measurement configuration to
+ * Normal, Positive bias and Negative bias
+ *
+ * 
+ * 0 - Normal measurement configuration (default): In normal measurement
+ *     configuration the device follows normal measurement flow. Pins BP
+ *     and BN are left floating and high impedance.
+ *
+ * 1 - Positive bias configuration: In positive bias configuration, a
+ *     positive current is forced across the resistive load on pins BP
+ *     and BN.
+ *
+ * 2 - Negative bias configuration. In negative bias configuration, a
+ *     negative current is forced across the resistive load on pins BP
+ *     and BN.
+ *
+ */
+static int hmc5843_set_meas_conf(struct hmc5843_data *data, u8 meas_conf)
+{
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_A,
+			HMC5843_MEAS_CONF_MASK, meas_conf);
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static ssize_t hmc5843_show_measurement_configuration(struct device *dev,
+						struct device_attribute *attr,
+						char *buf)
+{
+	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
+	int val;
+	int ret;
+
+	ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_A, &val);
+	if (ret)
+		return ret;
+	val &= HMC5843_MEAS_CONF_MASK;
+
+	return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t hmc5843_set_measurement_configuration(struct device *dev,
+						struct device_attribute *attr,
+						const char *buf,
+						size_t count)
+{
+	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
+	unsigned long meas_conf = 0;
+	int ret;
+
+	ret = kstrtoul(buf, 10, &meas_conf);
+	if (ret)
+		return ret;
+	if (meas_conf >= HMC5843_MEAS_CONF_MASK)
+		return -EINVAL;
+
+	ret = hmc5843_set_meas_conf(data, meas_conf);
+
+	return (ret < 0) ? ret : count;
+}
+
+static IIO_DEVICE_ATTR(meas_conf,
+			S_IWUSR | S_IRUGO,
+			hmc5843_show_measurement_configuration,
+			hmc5843_set_measurement_configuration,
+			0);
+
+static ssize_t hmc5843_show_samp_freq_avail(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
+	size_t len = 0;
+	int i;
+
+	for (i = 0; i < HMC5843_RATES; i++)
+		len += scnprintf(buf + len, PAGE_SIZE - len,
+			"%d.%d ", data->variant->regval_to_samp_freq[i][0],
+			data->variant->regval_to_samp_freq[i][1]);
+
+	/* replace trailing space by newline */
+	buf[len - 1] = '\n';
+
+	return len;
+}
+
+static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(hmc5843_show_samp_freq_avail);
+
+static int hmc5843_set_samp_freq(struct hmc5843_data *data, u8 rate)
+{
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_A,
+			HMC5843_RATE_MASK, rate << HMC5843_RATE_OFFSET);
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int hmc5843_get_samp_freq_index(struct hmc5843_data *data,
+				   int val, int val2)
+{
+	int i;
+
+	for (i = 0; i < HMC5843_RATES; i++)
+		if (val == data->variant->regval_to_samp_freq[i][0] &&
+			val2 == data->variant->regval_to_samp_freq[i][1])
+			return i;
+
+	return -EINVAL;
+}
+
+static int hmc5843_set_range_gain(struct hmc5843_data *data, u8 range)
+{
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = regmap_update_bits(data->regmap, HMC5843_CONFIG_REG_B,
+			HMC5843_RANGE_GAIN_MASK,
+			range << HMC5843_RANGE_GAIN_OFFSET);
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static ssize_t hmc5843_show_scale_avail(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
+
+	size_t len = 0;
+	int i;
+
+	for (i = 0; i < HMC5843_RANGE_GAINS; i++)
+		len += scnprintf(buf + len, PAGE_SIZE - len,
+			"0.%09d ", data->variant->regval_to_nanoscale[i]);
+
+	/* replace trailing space by newline */
+	buf[len - 1] = '\n';
+
+	return len;
+}
+
+static IIO_DEVICE_ATTR(scale_available, S_IRUGO,
+	hmc5843_show_scale_avail, NULL, 0);
+
+static int hmc5843_get_scale_index(struct hmc5843_data *data, int val, int val2)
+{
+	int i;
+
+	if (val != 0)
+		return -EINVAL;
+
+	for (i = 0; i < HMC5843_RANGE_GAINS; i++)
+		if (val2 == data->variant->regval_to_nanoscale[i])
+			return i;
+
+	return -EINVAL;
+}
+
+static int hmc5843_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct hmc5843_data *data = iio_priv(indio_dev);
+	int rval;
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		return hmc5843_read_measurement(data, chan->scan_index, val);
+	case IIO_CHAN_INFO_SCALE:
+		ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_B, &rval);
+		if (ret < 0)
+			return ret;
+		rval >>= HMC5843_RANGE_GAIN_OFFSET;
+		*val = 0;
+		*val2 = data->variant->regval_to_nanoscale[rval];
+		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		ret = regmap_read(data->regmap, HMC5843_CONFIG_REG_A, &rval);
+		if (ret < 0)
+			return ret;
+		rval >>= HMC5843_RATE_OFFSET;
+		*val = data->variant->regval_to_samp_freq[rval][0];
+		*val2 = data->variant->regval_to_samp_freq[rval][1];
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+	return -EINVAL;
+}
+
+static int hmc5843_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct hmc5843_data *data = iio_priv(indio_dev);
+	int rate, range;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		rate = hmc5843_get_samp_freq_index(data, val, val2);
+		if (rate < 0)
+			return -EINVAL;
+
+		return hmc5843_set_samp_freq(data, rate);
+	case IIO_CHAN_INFO_SCALE:
+		range = hmc5843_get_scale_index(data, val, val2);
+		if (range < 0)
+			return -EINVAL;
+
+		return hmc5843_set_range_gain(data, range);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int hmc5843_write_raw_get_fmt(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan, long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		return IIO_VAL_INT_PLUS_MICRO;
+	case IIO_CHAN_INFO_SCALE:
+		return IIO_VAL_INT_PLUS_NANO;
+	default:
+		return -EINVAL;
+	}
+}
+
+static irqreturn_t hmc5843_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct hmc5843_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = hmc5843_wait_measurement(data);
+	if (ret < 0) {
+		mutex_unlock(&data->lock);
+		goto done;
+	}
+
+	ret = regmap_bulk_read(data->regmap, HMC5843_DATA_OUT_MSB_REGS,
+			data->buffer, 3 * sizeof(__be16));
+
+	mutex_unlock(&data->lock);
+	if (ret < 0)
+		goto done;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+		iio_get_time_ns());
+
+done:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+#define HMC5843_CHANNEL(axis, idx)					\
+	{								\
+		.type = IIO_MAGN,					\
+		.modified = 1,						\
+		.channel2 = IIO_MOD_##axis,				\
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |	\
+			BIT(IIO_CHAN_INFO_SAMP_FREQ),			\
+		.scan_index = idx,					\
+		.scan_type = {						\
+			.sign = 's',					\
+			.realbits = 16,					\
+			.storagebits = 16,				\
+			.endianness = IIO_BE,				\
+		},							\
+	}
+
+static const struct iio_chan_spec hmc5843_channels[] = {
+	HMC5843_CHANNEL(X, 0),
+	HMC5843_CHANNEL(Y, 1),
+	HMC5843_CHANNEL(Z, 2),
+	IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
+/* Beware: Y and Z are exchanged on HMC5883 */
+static const struct iio_chan_spec hmc5883_channels[] = {
+	HMC5843_CHANNEL(X, 0),
+	HMC5843_CHANNEL(Z, 1),
+	HMC5843_CHANNEL(Y, 2),
+	IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
+static struct attribute *hmc5843_attributes[] = {
+	&iio_dev_attr_meas_conf.dev_attr.attr,
+	&iio_dev_attr_scale_available.dev_attr.attr,
+	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group hmc5843_group = {
+	.attrs = hmc5843_attributes,
+};
+
+static const struct hmc5843_chip_info hmc5843_chip_info_tbl[] = {
+	[HMC5843_ID] = {
+		.channels = hmc5843_channels,
+		.regval_to_samp_freq = hmc5843_regval_to_samp_freq,
+		.regval_to_nanoscale = hmc5843_regval_to_nanoscale,
+	},
+	[HMC5883_ID] = {
+		.channels = hmc5883_channels,
+		.regval_to_samp_freq = hmc5883_regval_to_samp_freq,
+		.regval_to_nanoscale = hmc5883_regval_to_nanoscale,
+	},
+	[HMC5883L_ID] = {
+		.channels = hmc5883_channels,
+		.regval_to_samp_freq = hmc5883_regval_to_samp_freq,
+		.regval_to_nanoscale = hmc5883l_regval_to_nanoscale,
+	},
+};
+
+static int hmc5843_init(struct hmc5843_data *data)
+{
+	int ret;
+	u8 id[3];
+
+	ret = regmap_bulk_read(data->regmap, HMC5843_ID_REG,
+			id, ARRAY_SIZE(id));
+	if (ret < 0)
+		return ret;
+	if (id[0] != 'H' || id[1] != '4' || id[2] != '3') {
+		dev_err(data->dev, "no HMC5843/5883/5883L sensor\n");
+		return -ENODEV;
+	}
+
+	ret = hmc5843_set_meas_conf(data, HMC5843_MEAS_CONF_NORMAL);
+	if (ret < 0)
+		return ret;
+	ret = hmc5843_set_samp_freq(data, HMC5843_RATE_DEFAULT);
+	if (ret < 0)
+		return ret;
+	ret = hmc5843_set_range_gain(data, HMC5843_RANGE_GAIN_DEFAULT);
+	if (ret < 0)
+		return ret;
+	return hmc5843_set_mode(data, HMC5843_MODE_CONVERSION_CONTINUOUS);
+}
+
+static const struct iio_info hmc5843_info = {
+	.attrs = &hmc5843_group,
+	.read_raw = &hmc5843_read_raw,
+	.write_raw = &hmc5843_write_raw,
+	.write_raw_get_fmt = &hmc5843_write_raw_get_fmt,
+	.driver_module = THIS_MODULE,
+};
+
+static const unsigned long hmc5843_scan_masks[] = {0x7, 0};
+
+
+int hmc5843_common_suspend(struct iio_dev *indio_dev)
+{
+	return hmc5843_set_mode(iio_priv(indio_dev),
+			HMC5843_MODE_CONVERSION_CONTINUOUS);
+}
+EXPORT_SYMBOL(hmc5843_common_suspend);
+
+int hmc5843_common_resume(struct iio_dev *indio_dev)
+{
+	return hmc5843_set_mode(iio_priv(indio_dev), HMC5843_MODE_SLEEP);
+}
+EXPORT_SYMBOL(hmc5843_common_resume);
+
+int hmc5843_common_probe(struct iio_dev *indio_dev, enum hmc5843_ids id)
+{
+	struct hmc5843_data *data;
+	int ret;
+
+	/* default settings at probe */
+	data = iio_priv(indio_dev);
+	data->variant = &hmc5843_chip_info_tbl[id];
+	mutex_init(&data->lock);
+
+	indio_dev->info = &hmc5843_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = data->variant->channels;
+	indio_dev->num_channels = 4;
+	indio_dev->available_scan_masks = hmc5843_scan_masks;
+
+	ret = hmc5843_init(data);
+	if (ret < 0)
+		return ret;
+
+	ret = iio_triggered_buffer_setup(indio_dev, NULL,
+		hmc5843_trigger_handler, NULL);
+	if (ret < 0)
+		return ret;
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0)
+		goto buffer_cleanup;
+
+	return 0;
+
+buffer_cleanup:
+	iio_triggered_buffer_cleanup(indio_dev);
+	return ret;
+}
+EXPORT_SYMBOL(hmc5843_common_probe);
+
+int hmc5843_common_remove(struct iio_dev *indio_dev)
+{
+	/*  sleep mode to save power */
+	hmc5843_set_mode(iio_priv(indio_dev), HMC5843_MODE_SLEEP);
+
+	iio_device_unregister(indio_dev);
+	iio_triggered_buffer_cleanup(indio_dev);
+
+	return 0;
+}
+EXPORT_SYMBOL(hmc5843_common_remove);
+
+MODULE_AUTHOR("Shubhrajyoti Datta <shubhrajyoti@ti.com>");
+MODULE_DESCRIPTION("HMC5843/5883/5883L core driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/staging/iio/magnetometer/hmc5843_i2c.c b/drivers/staging/iio/magnetometer/hmc5843_i2c.c
new file mode 100644
index 0000000..b3c92d9
--- /dev/null
+++ b/drivers/staging/iio/magnetometer/hmc5843_i2c.c
@@ -0,0 +1,106 @@
+/*
+ * i2c driver for hmc5843/5843/5883/5883l
+ *
+ * Split from hmc5843.c
+ * Copyright (C) Josef Gajdusek <atx@atx.name>
+ *
+ * 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.
+ *
+ * */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/triggered_buffer.h>
+
+#include "hmc5843.h"
+
+struct regmap_config hmc5843_i2c_regmap_config = {
+		.reg_bits = 8,
+		.val_bits = 8,
+
+		.rd_table = &hmc5843_readable_table,
+		.wr_table = &hmc5843_writable_table,
+		.volatile_table = &hmc5843_volatile_table,
+
+		.cache_type = REGCACHE_RBTREE,
+};
+
+static int hmc5843_i2c_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct hmc5843_data *data;
+	struct iio_dev *indio_dev;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (indio_dev == NULL)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, indio_dev);
+
+	data = iio_priv(indio_dev);
+	data->dev = &client->dev;
+	data->regmap = devm_regmap_init_i2c(client, &hmc5843_i2c_regmap_config);
+
+	indio_dev->name = id->name;
+	indio_dev->dev.parent = &client->dev;
+
+	return hmc5843_common_probe(indio_dev, id->driver_data);
+}
+
+static int hmc5843_i2c_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	return hmc5843_common_remove(indio_dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int hmc5843_i2c_suspend(struct device *dev)
+{
+	return hmc5843_common_suspend(i2c_get_clientdata(to_i2c_client(dev)));
+}
+
+static int hmc5843_i2c_resume(struct device *dev)
+{
+	return hmc5843_common_resume(i2c_get_clientdata(to_i2c_client(dev)));
+}
+
+static SIMPLE_DEV_PM_OPS(hmc5843_pm_ops,
+		hmc5843_i2c_suspend, hmc5843_i2c_resume);
+#define HMC5843_PM_OPS (&hmc5843_pm_ops)
+#else
+#define HMC5843_PM_OPS NULL
+#endif
+
+static const struct i2c_device_id hmc5843_id[] = {
+	{ "hmc5843", HMC5843_ID },
+	{ "hmc5883", HMC5883_ID },
+	{ "hmc5883l", HMC5883L_ID },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, hmc5843_id);
+
+static const struct of_device_id hmc5843_of_match[] = {
+	{ .compatible = "honeywell,hmc5843" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, hmc5843_of_match);
+
+static struct i2c_driver hmc5843_driver = {
+	.driver = {
+		.name	= "hmc5843",
+		.pm	= HMC5843_PM_OPS,
+		.of_match_table = hmc5843_of_match,
+	},
+	.id_table	= hmc5843_id,
+	.probe		= hmc5843_i2c_probe,
+	.remove		= hmc5843_i2c_remove,
+};
+module_i2c_driver(hmc5843_driver);
+
+MODULE_AUTHOR("Josef Gajdusek <atx@atx.name>");
+MODULE_DESCRIPTION("HMC5843/5883/5883L i2c driver");
+MODULE_LICENSE("GPL");
-- 
1.8.5.5