iio: imu: Add support for Kionix KMX61 sensor

Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports
raw accel/magn readings together with scale and sampling frequency.

Datasheet will be available at:
http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

3 files changed, 777 insertions, 0 deletions

diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
index 2b0e45133e9d..d675f43cb76a 100644
--- a/drivers/iio/imu/Kconfig
+++ b/drivers/iio/imu/Kconfig
@@ -25,6 +25,15 @@ config ADIS16480
           Say yes here to build support for Analog Devices ADIS16375, ADIS16480,
           ADIS16485, ADIS16488 inertial sensors.
 
+config KMX61
+        tristate "Kionix KMX61 6-axis accelerometer and magnetometer"
+        depends on I2C
+        help
+          Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer
+          and magnetometer.
+          To compile this driver as module, choose M here: the module will be called
+          kmx61.
+
 source "drivers/iio/imu/inv_mpu6050/Kconfig"
 
 endmenu
diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
index 114d2c17cbe2..e1e6e3d70e26 100644
--- a/drivers/iio/imu/Makefile
+++ b/drivers/iio/imu/Makefile
@@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
 obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
 
 obj-y += inv_mpu6050/
+
+obj-$(CONFIG_KMX61) += kmx61.o
diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
new file mode 100644
index 000000000000..f68b3ef1a575
--- /dev/null
+++ b/drivers/iio/imu/kmx61.c
@@ -0,0 +1,766 @@
+/*
+ * KMX61 - Kionix 6-axis Accelerometer/Magnetometer
+ *
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F).
+ *
+ * TODO: buffer, interrupt, thresholds, acpi, temperature sensor
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define KMX61_DRV_NAME "kmx61"
+
+#define KMX61_REG_WHO_AM_I      0x00
+
+/*
+ * three 16-bit accelerometer output registers for X/Y/Z axis
+ * we use only XOUT_L as a base register, all other addresses
+ * can be obtained by applying an offset and are provided here
+ * only for clarity.
+ */
+#define KMX61_ACC_XOUT_L        0x0A
+#define KMX61_ACC_XOUT_H        0x0B
+#define KMX61_ACC_YOUT_L        0x0C
+#define KMX61_ACC_YOUT_H        0x0D
+#define KMX61_ACC_ZOUT_L        0x0E
+#define KMX61_ACC_ZOUT_H        0x0F
+
+/*
+ * one 16-bit temperature output register
+ */
+#define KMX61_TEMP_L            0x10
+#define KMX61_TEMP_H            0x11
+
+/*
+ * three 16-bit magnetometer output registers for X/Y/Z axis
+ */
+#define KMX61_MAG_XOUT_L        0x12
+#define KMX61_MAG_XOUT_H        0x13
+#define KMX61_MAG_YOUT_L        0x14
+#define KMX61_MAG_YOUT_H        0x15
+#define KMX61_MAG_ZOUT_L        0x16
+#define KMX61_MAG_ZOUT_H        0x17
+
+#define KMX61_REG_ODCNTL        0x2C
+#define KMX61_REG_STBY          0x29
+#define KMX61_REG_CTRL1         0x2A
+
+#define KMX61_ACC_STBY_BIT      BIT(0)
+#define KMX61_MAG_STBY_BIT      BIT(1)
+#define KMX61_ACT_STBY_BIT      BIT(7)
+
+#define KMX61_ALL_STBY          (KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT)
+
+#define KMX61_REG_CTRL1_GSEL0_SHIFT     0
+#define KMX61_REG_CTRL1_GSEL1_SHIFT     1
+#define KMX61_REG_CTRL1_GSEL0_MASK      0x01
+#define KMX61_REG_CTRL1_GSEL1_MASK      0x02
+
+#define KMX61_REG_CTRL1_BIT_RES         BIT(4)
+
+#define KMX61_ACC_ODR_SHIFT     0
+#define KMX61_MAG_ODR_SHIFT     4
+#define KMX61_ACC_ODR_MASK      0x0F
+#define KMX61_MAG_ODR_MASK      0xF0
+
+#define KMX61_SLEEP_DELAY_MS    2000
+
+#define KMX61_CHIP_ID           0x12
+
+struct kmx61_data {
+        struct i2c_client *client;
+
+        /* serialize access to non-atomic ops, e.g set_mode */
+        struct mutex lock;
+        u8 range;
+        u8 odr_bits;
+
+        /* standby state */
+        u8 acc_stby;
+        u8 mag_stby;
+
+        /* power state */
+        bool acc_ps;
+        bool mag_ps;
+};
+
+enum kmx61_range {
+        KMX61_RANGE_2G,
+        KMX61_RANGE_4G,
+        KMX61_RANGE_8G,
+};
+
+enum kmx61_scan {
+        KMX61_SCAN_ACC_X,
+        KMX61_SCAN_ACC_Y,
+        KMX61_SCAN_ACC_Z,
+        KMX61_SCAN_TEMP,
+        KMX61_SCAN_MAG_X,
+        KMX61_SCAN_MAG_Y,
+        KMX61_SCAN_MAG_Z,
+};
+
+static const struct {
+        u16 uscale;
+        u8 gsel0;
+        u8 gsel1;
+} kmx61_scale_table[] = {
+        {9582, 0, 0},
+        {19163, 1, 0},
+        {38326, 0, 1},
+};
+
+/* KMX61 devices */
+#define KMX61_ACC       0x01
+#define KMX61_MAG       0x02
+
+static const struct {
+        int val;
+        int val2;
+        u8 odr_bits;
+} kmx61_samp_freq_table[] = { {12, 500000, 0x00},
+                        {25, 0, 0x01},
+                        {50, 0, 0x02},
+                        {100, 0, 0x03},
+                        {200, 0, 0x04},
+                        {400, 0, 0x05},
+                        {800, 0, 0x06},
+                        {1600, 0, 0x07},
+                        {0, 781000, 0x08},
+                        {1, 563000, 0x09},
+                        {3, 125000, 0x0A},
+                        {6, 250000, 0x0B} };
+
+static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326");
+static IIO_CONST_ATTR(magn_scale_available, "0.001465");
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
+        "0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800");
+
+static struct attribute *kmx61_attributes[] = {
+        &iio_const_attr_accel_scale_available.dev_attr.attr,
+        &iio_const_attr_magn_scale_available.dev_attr.attr,
+        &iio_const_attr_sampling_frequency_available.dev_attr.attr,
+        NULL,
+};
+
+static const struct attribute_group kmx61_attribute_group = {
+        .attrs = kmx61_attributes,
+};
+
+#define KMX61_ACC_CHAN(_axis, _index) { \
+        .type = IIO_ACCEL, \
+        .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), \
+        .address = KMX61_ACC, \
+        .scan_index = _index, \
+        .scan_type = { \
+                .sign = 's', \
+                .realbits = 12, \
+                .storagebits = 16, \
+                .shift = 4, \
+                .endianness = IIO_LE, \
+        }, \
+}
+
+#define KMX61_MAG_CHAN(_axis, _index) { \
+        .type = IIO_MAGN, \
+        .modified = 1, \
+        .channel2 = IIO_MOD_ ## _axis, \
+        .address = KMX61_MAG, \
+        .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 = _index, \
+        .scan_type = { \
+                .sign = 's', \
+                .realbits = 14, \
+                .storagebits = 16, \
+                .shift = 2, \
+                .endianness = IIO_LE, \
+        }, \
+}
+
+static const struct iio_chan_spec kmx61_channels[] = {
+        KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X),
+        KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y),
+        KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z),
+        KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X),
+        KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y),
+        KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z),
+};
+
+static int kmx61_convert_freq_to_bit(int val, int val2)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(kmx61_samp_freq_table); i++)
+                if (val == kmx61_samp_freq_table[i].val &&
+                    val2 == kmx61_samp_freq_table[i].val2)
+                        return kmx61_samp_freq_table[i].odr_bits;
+        return -EINVAL;
+}
+/**
+ * kmx61_set_mode() - set KMX61 device operating mode
+ * @data - kmx61 device private data pointer
+ * @mode - bitmask, indicating operating mode for @device
+ * @device - bitmask, indicating device for which @mode needs to be set
+ * @update - update stby bits stored in device's private  @data
+ *
+ * For each sensor (accelerometer/magnetometer) there are two operating modes
+ * STANDBY and OPERATION. Neither accel nor magn can be disabled independently
+ * if they are both enabled. Internal sensors state is saved in acc_stby and
+ * mag_stby members of driver's private @data.
+ */
+static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device,
+                          bool update)
+{
+        int ret;
+        int acc_stby = -1, mag_stby = -1;
+
+        ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
+        if (ret < 0) {
+                dev_err(&data->client->dev, "Error reading reg_stby\n");
+                return ret;
+        }
+        if (device & KMX61_ACC) {
+                if (mode & KMX61_ACC_STBY_BIT) {
+                        ret |= KMX61_ACC_STBY_BIT;
+                        acc_stby = 1;
+                } else {
+                        ret &= ~KMX61_ACC_STBY_BIT;
+                        acc_stby = 0;
+                }
+        }
+
+        if (device & KMX61_MAG) {
+                if (mode & KMX61_MAG_STBY_BIT) {
+                        ret |= KMX61_MAG_STBY_BIT;
+                        mag_stby = 1;
+                } else {
+                        ret &= ~KMX61_MAG_STBY_BIT;
+                        mag_stby = 0;
+                }
+        }
+
+        ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret);
+        if (ret < 0) {
+                dev_err(&data->client->dev, "Error writing reg_stby\n");
+                return ret;
+        }
+
+        if (acc_stby != -1 && update)
+                data->acc_stby = !!acc_stby;
+        if (mag_stby != -1 && update)
+                data->mag_stby = !!mag_stby;
+
+        return ret;
+}
+
+static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device)
+{
+        int ret;
+
+        ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
+        if (ret < 0) {
+                dev_err(&data->client->dev, "Error reading reg_stby\n");
+                return ret;
+        }
+        *mode = 0;
+
+        if (device & KMX61_ACC) {
+                if (ret & KMX61_ACC_STBY_BIT)
+                        *mode |= KMX61_ACC_STBY_BIT;
+                else
+                        *mode &= ~KMX61_ACC_STBY_BIT;
+        }
+
+        if (device & KMX61_MAG) {
+                if (ret & KMX61_MAG_STBY_BIT)
+                        *mode |= KMX61_MAG_STBY_BIT;
+                else
+                        *mode &= ~KMX61_MAG_STBY_BIT;
+        }
+
+        return 0;
+}
+
+static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device)
+{
+        int ret;
+        u8 mode;
+        int lodr_bits, odr_bits;
+
+        ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG);
+        if (ret < 0)
+                return ret;
+
+        lodr_bits = kmx61_convert_freq_to_bit(val, val2);
+        if (lodr_bits < 0)
+                return lodr_bits;
+
+        /* To change ODR, accel and magn must be in STDBY */
+        ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG,
+                             true);
+        if (ret < 0)
+                return ret;
+
+        odr_bits = 0;
+        if (device & KMX61_ACC)
+                odr_bits |= lodr_bits;
+        if (device & KMX61_MAG)
+                odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT);
+
+        ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL,
+                                        odr_bits);
+        if (ret < 0)
+                return ret;
+
+        ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG, true);
+        if (ret < 0)
+                return ret;
+
+        data->odr_bits = lodr_bits;
+
+        return 0;
+}
+
+static
+int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device)
+{       int i;
+        u8 lodr_bits;
+
+        if (device & KMX61_ACC)
+                lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) &
+                             KMX61_ACC_ODR_MASK;
+        else if (device & KMX61_MAG)
+                lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) &
+                             KMX61_MAG_ODR_MASK;
+        else
+                return -EINVAL;
+
+        for (i = 0; i < ARRAY_SIZE(kmx61_samp_freq_table); i++)
+                if (lodr_bits == kmx61_samp_freq_table[i].odr_bits) {
+                        *val = kmx61_samp_freq_table[i].val;
+                        *val2 = kmx61_samp_freq_table[i].val2;
+                        return 0;
+                }
+        return -EINVAL;
+}
+
+static int kmx61_set_range(struct kmx61_data *data, int range)
+{
+        int ret;
+
+        ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1);
+        if (ret < 0) {
+                dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
+                return ret;
+        }
+
+        ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK);
+        ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT;
+        ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT;
+
+        ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret);
+        if (ret < 0) {
+                dev_err(&data->client->dev, "Error writing reg_ctrl1\n");
+                return ret;
+        }
+
+        data->range = range;
+
+        return 0;
+}
+
+static int kmx61_set_scale(struct kmx61_data *data, int uscale)
+{
+        int ret, i;
+        u8  mode;
+
+        for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) {
+                if (kmx61_scale_table[i].uscale == uscale) {
+                        ret = kmx61_get_mode(data, &mode,
+                                             KMX61_ACC | KMX61_MAG);
+                        if (ret < 0)
+                                return ret;
+
+                        ret = kmx61_set_mode(data, KMX61_ALL_STBY,
+                                             KMX61_ACC | KMX61_MAG, true);
+                        if (ret < 0)
+                                return ret;
+
+                        ret = kmx61_set_range(data, i);
+                        if (ret < 0)
+                                return ret;
+
+                        return  kmx61_set_mode(data, mode,
+                                               KMX61_ACC | KMX61_MAG, true);
+                }
+        }
+        return -EINVAL;
+}
+
+static int kmx61_chip_init(struct kmx61_data *data)
+{
+        int ret;
+
+        ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I);
+        if (ret < 0) {
+                dev_err(&data->client->dev, "Error reading who_am_i\n");
+                return ret;
+        }
+
+        if (ret != KMX61_CHIP_ID) {
+                dev_err(&data->client->dev,
+                        "Wrong chip id, got %x expected %x\n",
+                         ret, KMX61_CHIP_ID);
+                return -EINVAL;
+        }
+
+        /* set accel 12bit, 4g range */
+        ret = kmx61_set_range(data, KMX61_RANGE_4G);
+        if (ret < 0)
+                return ret;
+
+        /* set acc/magn to OPERATION mode */
+        ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG, true);
+        if (ret < 0)
+                return ret;
+
+        return 0;
+}
+/**
+ * kmx61_set_power_state() - set power state for kmx61 @device
+ * @data - kmx61 device private pointer
+ * @on - power state to be set for @device
+ * @device - bitmask indicating device for which @on state needs to be set
+ *
+ * Notice that when ACC power state needs to be set to ON and MAG is in
+ * OPERATION then we know that kmx61_runtime_resume was already called
+ * so we must set ACC OPERATION mode here. The same happens when MAG power
+ * state needs to be set to ON and ACC is in OPERATION.
+ */
+static int kmx61_set_power_state(struct kmx61_data *data, bool on, u8 device)
+{
+#ifdef CONFIG_PM_RUNTIME
+        int ret;
+
+        if (device & KMX61_ACC) {
+                if (on && !data->acc_ps && !data->mag_stby)
+                        kmx61_set_mode(data, 0, KMX61_ACC, true);
+                data->acc_ps = on;
+        }
+        if (device & KMX61_MAG) {
+                if (on && !data->mag_ps && !data->acc_stby)
+                        kmx61_set_mode(data, 0, KMX61_MAG, true);
+                data->mag_ps = on;
+        }
+
+        if (on) {
+                ret = pm_runtime_get_sync(&data->client->dev);
+        } else {
+                pm_runtime_mark_last_busy(&data->client->dev);
+                ret = pm_runtime_put_autosuspend(&data->client->dev);
+        }
+        if (ret < 0) {
+                dev_err(&data->client->dev,
+                        "Failed: kmx61_set_power_state for %d, ret %d\n",
+                        on, ret);
+                return ret;
+        }
+#endif
+        return 0;
+}
+
+static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset)
+{
+        int ret;
+        u8 reg = base + offset * 2;
+
+        ret = i2c_smbus_read_word_data(data->client, reg);
+        if (ret < 0) {
+                dev_err(&data->client->dev, "failed to read reg at %x\n", reg);
+                return ret;
+        }
+
+        return ret;
+}
+
+static int kmx61_read_raw(struct iio_dev *indio_dev,
+                              struct iio_chan_spec const *chan, int *val,
+                              int *val2, long mask)
+{
+        struct kmx61_data *data = iio_priv(indio_dev);
+        int ret;
+        u8 base_reg;
+
+        switch (mask) {
+        case IIO_CHAN_INFO_RAW:
+                switch (chan->type) {
+                case IIO_ACCEL:
+                case IIO_MAGN:
+                        base_reg = KMX61_ACC_XOUT_L;
+                        break;
+                default:
+                        return -EINVAL;
+                }
+                mutex_lock(&data->lock);
+
+                kmx61_set_power_state(data, true, chan->address);
+                ret = kmx61_read_measurement(data, base_reg, chan->scan_index);
+                if (ret < 0) {
+                        kmx61_set_power_state(data, false, chan->address);
+                        mutex_unlock(&data->lock);
+                        return ret;
+                }
+                *val = sign_extend32(ret >> chan->scan_type.shift,
+                                     chan->scan_type.realbits - 1);
+                kmx61_set_power_state(data, false, chan->address);
+
+                mutex_unlock(&data->lock);
+                return IIO_VAL_INT;
+        case IIO_CHAN_INFO_SCALE:
+                switch (chan->type) {
+                case IIO_ACCEL:
+                        *val = 0;
+                        *val2 = kmx61_scale_table[data->range].uscale;
+                        return IIO_VAL_INT_PLUS_MICRO;
+                case IIO_MAGN:
+                        /* 14 bits res, 1465 microGauss per magn count */
+                        *val = 0;
+                        *val2 = 1465;
+                        return IIO_VAL_INT_PLUS_MICRO;
+                default:
+                        return -EINVAL;
+                }
+        case IIO_CHAN_INFO_SAMP_FREQ:
+                if (chan->type != IIO_ACCEL && chan->type != IIO_MAGN)
+                        return -EINVAL;
+
+                mutex_lock(&data->lock);
+                ret = kmx61_get_odr(data, val, val2, chan->address);
+                mutex_unlock(&data->lock);
+                if (ret)
+                        return -EINVAL;
+                return IIO_VAL_INT_PLUS_MICRO;
+        }
+        return -EINVAL;
+}
+
+static int kmx61_write_raw(struct iio_dev *indio_dev,
+                               struct iio_chan_spec const *chan, int val,
+                               int val2, long mask)
+{
+        struct kmx61_data *data = iio_priv(indio_dev);
+        int ret;
+
+        switch (mask) {
+        case IIO_CHAN_INFO_SAMP_FREQ:
+                if (chan->type != IIO_ACCEL && chan->type != IIO_MAGN)
+                        return -EINVAL;
+
+                mutex_lock(&data->lock);
+                ret = kmx61_set_odr(data, val, val2, chan->address);
+                mutex_unlock(&data->lock);
+                return ret;
+        case IIO_CHAN_INFO_SCALE:
+                switch (chan->type) {
+                case IIO_ACCEL:
+                        if (val != 0)
+                                return -EINVAL;
+                        mutex_lock(&data->lock);
+                        ret = kmx61_set_scale(data, val2);
+                        mutex_unlock(&data->lock);
+                        return ret;
+                default:
+                        return -EINVAL;
+                }
+                return ret;
+        default:
+                return -EINVAL;
+        }
+        return ret;
+}
+
+static const struct iio_info kmx61_info = {
+        .driver_module          = THIS_MODULE,
+        .read_raw               = kmx61_read_raw,
+        .write_raw              = kmx61_write_raw,
+        .attrs                  = &kmx61_attribute_group,
+};
+
+static int kmx61_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+        struct kmx61_data *data;
+        struct iio_dev *indio_dev;
+        int ret;
+        const char *name = NULL;
+
+        indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+        if (!indio_dev)
+                return -ENOMEM;
+
+        data = iio_priv(indio_dev);
+        i2c_set_clientdata(client, indio_dev);
+        data->client = client;
+
+        if (id)
+                name = id->name;
+
+        indio_dev->dev.parent = &client->dev;
+        indio_dev->channels = kmx61_channels;
+        indio_dev->num_channels = ARRAY_SIZE(kmx61_channels);
+        indio_dev->name = name;
+        indio_dev->modes = INDIO_DIRECT_MODE;
+        indio_dev->info = &kmx61_info;
+
+        mutex_init(&data->lock);
+
+        ret = kmx61_chip_init(data);
+        if (ret < 0)
+                return ret;
+
+        ret = iio_device_register(indio_dev);
+        if (ret < 0) {
+                dev_err(&client->dev, "Failed to register iio device\n");
+                goto err_iio_device_register;
+        }
+
+        ret = pm_runtime_set_active(&client->dev);
+        if (ret < 0)
+                goto err_pm_runtime_set_active;
+
+        pm_runtime_enable(&client->dev);
+        pm_runtime_set_autosuspend_delay(&client->dev, KMX61_SLEEP_DELAY_MS);
+        pm_runtime_use_autosuspend(&client->dev);
+
+        return 0;
+
+err_pm_runtime_set_active:
+        iio_device_unregister(indio_dev);
+err_iio_device_register:
+        kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true);
+        return ret;
+}
+
+static int kmx61_remove(struct i2c_client *client)
+{
+        struct iio_dev *indio_dev = i2c_get_clientdata(client);
+        struct kmx61_data *data = iio_priv(indio_dev);
+        int ret;
+
+        pm_runtime_disable(&client->dev);
+        pm_runtime_set_suspended(&client->dev);
+        pm_runtime_put_noidle(&client->dev);
+
+        iio_device_unregister(indio_dev);
+
+        mutex_lock(&data->lock);
+        ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true);
+        mutex_unlock(&data->lock);
+
+        return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int kmx61_suspend(struct device *dev)
+{
+        struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+        struct kmx61_data *data = iio_priv(indio_dev);
+        int ret;
+
+        mutex_lock(&data->lock);
+        ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG,
+                             false);
+        mutex_unlock(&data->lock);
+
+        return ret;
+}
+
+static int kmx61_resume(struct device *dev)
+{
+        struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+        struct kmx61_data *data = iio_priv(indio_dev);
+        u8 stby = 0;
+
+        if (data->acc_stby)
+                stby |= KMX61_ACC_STBY_BIT;
+        if (data->mag_stby)
+                stby |= KMX61_MAG_STBY_BIT;
+
+        return kmx61_set_mode(data, stby, KMX61_ACC | KMX61_MAG, true);
+}
+#endif
+
+#ifdef CONFIG_PM_RUNTIME
+static int kmx61_runtime_suspend(struct device *dev)
+{
+        struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+        struct kmx61_data *data = iio_priv(indio_dev);
+        int ret;
+
+        mutex_lock(&data->lock);
+        ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true);
+        mutex_unlock(&data->lock);
+
+        return ret;
+}
+
+static int kmx61_runtime_resume(struct device *dev)
+{
+        struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+        struct kmx61_data *data = iio_priv(indio_dev);
+        u8 stby = 0;
+
+        if (!data->acc_ps)
+                stby |= KMX61_ACC_STBY_BIT;
+        if (!data->mag_ps)
+                stby |= KMX61_MAG_STBY_BIT;
+
+        return kmx61_set_mode(data, stby, KMX61_ACC | KMX61_MAG, true);
+}
+#endif
+
+static const struct dev_pm_ops kmx61_pm_ops = {
+        SET_SYSTEM_SLEEP_PM_OPS(kmx61_suspend, kmx61_resume)
+        SET_RUNTIME_PM_OPS(kmx61_runtime_suspend, kmx61_runtime_resume, NULL)
+};
+
+static const struct i2c_device_id kmx61_id[] = {
+        {"kmx611021", 0},
+        {}
+};
+
+MODULE_DEVICE_TABLE(i2c, kmx61_id);
+
+static struct i2c_driver kmx61_driver = {
+        .driver = {
+                .name = KMX61_DRV_NAME,
+                .pm = &kmx61_pm_ops,
+        },
+        .probe          = kmx61_probe,
+        .remove         = kmx61_remove,
+        .id_table       = kmx61_id,
+};
+
+module_i2c_driver(kmx61_driver);
+
+MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
+MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver");
+MODULE_LICENSE("GPL v2");