14 files changed, 1485 insertions, 147 deletions

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 7c9a9a94a8ce..00e7bcbdbe24 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -136,4 +136,25 @@ config MMA9553
 
 	  To compile this driver as a module, choose M here: the module
 	  will be called mma9553.
+
+config STK8312
+	tristate "Sensortek STK8312 3-Axis Accelerometer Driver"
+	depends on I2C
+	help
+	  Say yes here to get support for the Sensortek STK8312 3-axis
+	  accelerometer.
+
+	  Choosing M will build the driver as a module. If so, the module
+	  will be called stk8312.
+
+config STK8BA50
+	tristate "Sensortek STK8BA50 3-Axis Accelerometer Driver"
+	depends on I2C
+	help
+	  Say yes here to get support for the Sensortek STK8BA50 3-axis
+	  accelerometer.
+
+	  Choosing M will build the driver as a module. If so, the module
+	  will be called stk8ba50.
+
 endmenu
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index 99d89e46cad1..ebd2675b2a02 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -14,6 +14,9 @@ obj-$(CONFIG_MMA9551_CORE)	+= mma9551_core.o
 obj-$(CONFIG_MMA9551)		+= mma9551.o
 obj-$(CONFIG_MMA9553)		+= mma9553.o
 
+obj-$(CONFIG_STK8312)		+= stk8312.o
+obj-$(CONFIG_STK8BA50)		+= stk8ba50.o
+
 obj-$(CONFIG_IIO_SSP_SENSORS_COMMONS) += ssp_accel_sensor.o
 
 obj-$(CONFIG_IIO_ST_ACCEL_3AXIS) += st_accel.o
diff --git a/drivers/iio/accel/bmc150-accel.c b/drivers/iio/accel/bmc150-accel.c
index 73e87739d219..4e70f51c2370 100644
--- a/drivers/iio/accel/bmc150-accel.c
+++ b/drivers/iio/accel/bmc150-accel.c
@@ -196,7 +196,7 @@ struct bmc150_accel_data {
 	u32 slope_thres;
 	u32 range;
 	int ev_enable_state;
-	int64_t timestamp, old_timestamp;
+	int64_t timestamp, old_timestamp; /* Only used in hw fifo mode. */
 	const struct bmc150_accel_chip_info *chip_info;
 };
 
@@ -1183,7 +1183,6 @@ static const struct iio_info bmc150_accel_info = {
 	.write_event_value	= bmc150_accel_write_event,
 	.write_event_config	= bmc150_accel_write_event_config,
 	.read_event_config	= bmc150_accel_read_event_config,
-	.validate_trigger	= bmc150_accel_validate_trigger,
 	.driver_module		= THIS_MODULE,
 };
 
@@ -1222,7 +1221,7 @@ static irqreturn_t bmc150_accel_trigger_handler(int irq, void *p)
 	mutex_unlock(&data->mutex);
 
 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
-					   data->timestamp);
+					   pf->timestamp);
 err_read:
 	iio_trigger_notify_done(indio_dev->trig);
 
@@ -1535,6 +1534,13 @@ static int bmc150_accel_fifo_set_mode(struct bmc150_accel_data *data)
 	return ret;
 }
 
+static int bmc150_accel_buffer_preenable(struct iio_dev *indio_dev)
+{
+	struct bmc150_accel_data *data = iio_priv(indio_dev);
+
+	return bmc150_accel_set_power_state(data, true);
+}
+
 static int bmc150_accel_buffer_postenable(struct iio_dev *indio_dev)
 {
 	struct bmc150_accel_data *data = iio_priv(indio_dev);
@@ -1591,9 +1597,18 @@ out:
 	return 0;
 }
 
+static int bmc150_accel_buffer_postdisable(struct iio_dev *indio_dev)
+{
+	struct bmc150_accel_data *data = iio_priv(indio_dev);
+
+	return bmc150_accel_set_power_state(data, false);
+}
+
 static const struct iio_buffer_setup_ops bmc150_accel_buffer_ops = {
+	.preenable = bmc150_accel_buffer_preenable,
 	.postenable = bmc150_accel_buffer_postenable,
 	.predisable = bmc150_accel_buffer_predisable,
+	.postdisable = bmc150_accel_buffer_postdisable,
 };
 
 static int bmc150_accel_probe(struct i2c_client *client,
@@ -1636,6 +1651,15 @@ static int bmc150_accel_probe(struct i2c_client *client,
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &bmc150_accel_info;
 
+	ret = iio_triggered_buffer_setup(indio_dev,
+					 &iio_pollfunc_store_time,
+					 bmc150_accel_trigger_handler,
+					 &bmc150_accel_buffer_ops);
+	if (ret < 0) {
+		dev_err(&client->dev, "Failed: iio triggered buffer setup\n");
+		return ret;
+	}
+
 	if (client->irq < 0)
 		client->irq = bmc150_accel_gpio_probe(client, data);
 
@@ -1648,7 +1672,7 @@ static int bmc150_accel_probe(struct i2c_client *client,
 						BMC150_ACCEL_IRQ_NAME,
 						indio_dev);
 		if (ret)
-			return ret;
+			goto err_buffer_cleanup;
 
 		/*
 		 * Set latched mode interrupt. While certain interrupts are
@@ -1661,24 +1685,14 @@ static int bmc150_accel_probe(struct i2c_client *client,
 					     BMC150_ACCEL_INT_MODE_LATCH_RESET);
 		if (ret < 0) {
 			dev_err(&data->client->dev, "Error writing reg_int_rst_latch\n");
-			return ret;
+			goto err_buffer_cleanup;
 		}
 
 		bmc150_accel_interrupts_setup(indio_dev, data);
 
 		ret = bmc150_accel_triggers_setup(indio_dev, data);
 		if (ret)
-			return ret;
-
-		ret = iio_triggered_buffer_setup(indio_dev,
-						 &iio_pollfunc_store_time,
-						 bmc150_accel_trigger_handler,
-						 &bmc150_accel_buffer_ops);
-		if (ret < 0) {
-			dev_err(&client->dev,
-				"Failed: iio triggered buffer setup\n");
-			goto err_trigger_unregister;
-		}
+			goto err_buffer_cleanup;
 
 		if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C) ||
 		    i2c_check_functionality(client->adapter,
@@ -1692,7 +1706,7 @@ static int bmc150_accel_probe(struct i2c_client *client,
 	ret = iio_device_register(indio_dev);
 	if (ret < 0) {
 		dev_err(&client->dev, "Unable to register iio device\n");
-		goto err_buffer_cleanup;
+		goto err_trigger_unregister;
 	}
 
 	ret = pm_runtime_set_active(&client->dev);
@@ -1708,11 +1722,10 @@ static int bmc150_accel_probe(struct i2c_client *client,
 
 err_iio_unregister:
 	iio_device_unregister(indio_dev);
-err_buffer_cleanup:
-	if (indio_dev->pollfunc)
-		iio_triggered_buffer_cleanup(indio_dev);
 err_trigger_unregister:
 	bmc150_accel_unregister_triggers(data, BMC150_ACCEL_TRIGGERS - 1);
+err_buffer_cleanup:
+	iio_triggered_buffer_cleanup(indio_dev);
 
 	return ret;
 }
@@ -1730,6 +1743,8 @@ static int bmc150_accel_remove(struct i2c_client *client)
 
 	bmc150_accel_unregister_triggers(data, BMC150_ACCEL_TRIGGERS - 1);
 
+	iio_triggered_buffer_cleanup(indio_dev);
+
 	mutex_lock(&data->mutex);
 	bmc150_accel_set_mode(data, BMC150_ACCEL_SLEEP_MODE_DEEP_SUSPEND, 0);
 	mutex_unlock(&data->mutex);
diff --git a/drivers/iio/accel/hid-sensor-accel-3d.c b/drivers/iio/accel/hid-sensor-accel-3d.c
index 2b4fad6998c1..ab1e238d5c75 100644
--- a/drivers/iio/accel/hid-sensor-accel-3d.c
+++ b/drivers/iio/accel/hid-sensor-accel-3d.c
@@ -299,7 +299,6 @@ static int hid_accel_3d_probe(struct platform_device *pdev)
 	struct iio_dev *indio_dev;
 	struct accel_3d_state *accel_state;
 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
-	struct iio_chan_spec *channels;
 
 	indio_dev = devm_iio_device_alloc(&pdev->dev,
 					  sizeof(struct accel_3d_state));
@@ -320,21 +319,21 @@ static int hid_accel_3d_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	channels = kmemdup(accel_3d_channels, sizeof(accel_3d_channels),
-			   GFP_KERNEL);
-	if (!channels) {
+	indio_dev->channels = kmemdup(accel_3d_channels,
+				      sizeof(accel_3d_channels), GFP_KERNEL);
+	if (!indio_dev->channels) {
 		dev_err(&pdev->dev, "failed to duplicate channels\n");
 		return -ENOMEM;
 	}
 
-	ret = accel_3d_parse_report(pdev, hsdev, channels,
-					HID_USAGE_SENSOR_ACCEL_3D, accel_state);
+	ret = accel_3d_parse_report(pdev, hsdev,
+				    (struct iio_chan_spec *)indio_dev->channels,
+				    HID_USAGE_SENSOR_ACCEL_3D, accel_state);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to setup attributes\n");
 		goto error_free_dev_mem;
 	}
 
-	indio_dev->channels = channels;
 	indio_dev->num_channels = ARRAY_SIZE(accel_3d_channels);
 	indio_dev->dev.parent = &pdev->dev;
 	indio_dev->info = &accel_3d_info;
@@ -400,7 +399,7 @@ static int hid_accel_3d_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static struct platform_device_id hid_accel_3d_ids[] = {
+static const struct platform_device_id hid_accel_3d_ids[] = {
 	{
 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 		.name = "HID-SENSOR-200073",
diff --git a/drivers/iio/accel/kxcjk-1013.c b/drivers/iio/accel/kxcjk-1013.c
index 51da3692d561..0d9bd35ff258 100644
--- a/drivers/iio/accel/kxcjk-1013.c
+++ b/drivers/iio/accel/kxcjk-1013.c
@@ -875,15 +875,18 @@ static int kxcjk1013_write_event_config(struct iio_dev *indio_dev,
 	return 0;
 }
 
-static int kxcjk1013_validate_trigger(struct iio_dev *indio_dev,
-				      struct iio_trigger *trig)
+static int kxcjk1013_buffer_preenable(struct iio_dev *indio_dev)
 {
 	struct kxcjk1013_data *data = iio_priv(indio_dev);
 
-	if (data->dready_trig != trig && data->motion_trig != trig)
-		return -EINVAL;
+	return kxcjk1013_set_power_state(data, true);
+}
 
-	return 0;
+static int kxcjk1013_buffer_postdisable(struct iio_dev *indio_dev)
+{
+	struct kxcjk1013_data *data = iio_priv(indio_dev);
+
+	return kxcjk1013_set_power_state(data, false);
 }
 
 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
@@ -935,6 +938,13 @@ static const struct iio_chan_spec kxcjk1013_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(3),
 };
 
+static const struct iio_buffer_setup_ops kxcjk1013_buffer_setup_ops = {
+	.preenable		= kxcjk1013_buffer_preenable,
+	.postenable		= iio_triggered_buffer_postenable,
+	.postdisable		= kxcjk1013_buffer_postdisable,
+	.predisable		= iio_triggered_buffer_predisable,
+};
+
 static const struct iio_info kxcjk1013_info = {
 	.attrs			= &kxcjk1013_attrs_group,
 	.read_raw		= kxcjk1013_read_raw,
@@ -943,7 +953,6 @@ static const struct iio_info kxcjk1013_info = {
 	.write_event_value	= kxcjk1013_write_event,
 	.write_event_config	= kxcjk1013_write_event_config,
 	.read_event_config	= kxcjk1013_read_event_config,
-	.validate_trigger	= kxcjk1013_validate_trigger,
 	.driver_module		= THIS_MODULE,
 };
 
@@ -1147,8 +1156,10 @@ static const char *kxcjk1013_match_acpi_device(struct device *dev,
 	id = acpi_match_device(dev->driver->acpi_match_table, dev);
 	if (!id)
 		return NULL;
+
 	if (strcmp(id->id, "SMO8500") == 0)
 		*is_smo8500_device = true;
+
 	*chipset = (enum kx_chipset)id->driver_data;
 
 	return dev_name(dev);
@@ -1163,6 +1174,7 @@ static int kxcjk1013_gpio_probe(struct i2c_client *client,
 
 	if (!client)
 		return -EINVAL;
+
 	if (data->is_smo8500_device)
 		return -ENOTSUPP;
 
@@ -1276,16 +1288,15 @@ static int kxcjk1013_probe(struct i2c_client *client,
 			data->motion_trig = NULL;
 			goto err_trigger_unregister;
 		}
+	}
 
-		ret = iio_triggered_buffer_setup(indio_dev,
-						&iio_pollfunc_store_time,
-						kxcjk1013_trigger_handler,
-						NULL);
-		if (ret < 0) {
-			dev_err(&client->dev,
-					"iio triggered buffer setup failed\n");
-			goto err_trigger_unregister;
-		}
+	ret = iio_triggered_buffer_setup(indio_dev,
+					 &iio_pollfunc_store_time,
+					 kxcjk1013_trigger_handler,
+					 &kxcjk1013_buffer_setup_ops);
+	if (ret < 0) {
+		dev_err(&client->dev, "iio triggered buffer setup failed\n");
+		goto err_trigger_unregister;
 	}
 
 	ret = iio_device_register(indio_dev);
@@ -1418,6 +1429,7 @@ static const struct dev_pm_ops kxcjk1013_pm_ops = {
 static const struct acpi_device_id kx_acpi_match[] = {
 	{"KXCJ1013", KXCJK1013},
 	{"KXCJ1008", KXCJ91008},
+	{"KXCJ9000", KXCJ91008},
 	{"KXTJ1009", KXTJ21009},
 	{"SMO8500",  KXCJ91008},
 	{ },
diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
index 5b80657883bb..e8e2077c7244 100644
--- a/drivers/iio/accel/mma8452.c
+++ b/drivers/iio/accel/mma8452.c
@@ -9,7 +9,7 @@
  *
  * 7-bit I2C slave address 0x1c/0x1d (pin selectable)
  *
- * TODO: interrupt, thresholding, orientation / freefall events, autosleep
+ * TODO: orientation / freefall events, autosleep
  */
 
 #include <linux/module.h>
@@ -18,20 +18,42 @@
 #include <linux/iio/sysfs.h>
 #include <linux/iio/trigger_consumer.h>
 #include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
 #include <linux/iio/triggered_buffer.h>
+#include <linux/iio/events.h>
 #include <linux/delay.h>
 
 #define MMA8452_STATUS 0x00
 #define MMA8452_OUT_X 0x01 /* MSB first, 12-bit  */
 #define MMA8452_OUT_Y 0x03
 #define MMA8452_OUT_Z 0x05
+#define MMA8452_INT_SRC 0x0c
 #define MMA8452_WHO_AM_I 0x0d
 #define MMA8452_DATA_CFG 0x0e
+#define MMA8452_HP_FILTER_CUTOFF 0x0f
+#define MMA8452_HP_FILTER_CUTOFF_SEL_MASK	(BIT(0) | BIT(1))
+#define MMA8452_TRANSIENT_CFG 0x1d
+#define MMA8452_TRANSIENT_CFG_ELE		BIT(4)
+#define MMA8452_TRANSIENT_CFG_CHAN(chan)	BIT(chan + 1)
+#define MMA8452_TRANSIENT_CFG_HPF_BYP		BIT(0)
+#define MMA8452_TRANSIENT_SRC 0x1e
+#define MMA8452_TRANSIENT_SRC_XTRANSE		BIT(1)
+#define MMA8452_TRANSIENT_SRC_YTRANSE		BIT(3)
+#define MMA8452_TRANSIENT_SRC_ZTRANSE		BIT(5)
+#define MMA8452_TRANSIENT_THS 0x1f
+#define MMA8452_TRANSIENT_THS_MASK	0x7f
+#define MMA8452_TRANSIENT_COUNT 0x20
 #define MMA8452_OFF_X 0x2f
 #define MMA8452_OFF_Y 0x30
 #define MMA8452_OFF_Z 0x31
 #define MMA8452_CTRL_REG1 0x2a
 #define MMA8452_CTRL_REG2 0x2b
+#define MMA8452_CTRL_REG2_RST		BIT(6)
+#define MMA8452_CTRL_REG4 0x2d
+#define MMA8452_CTRL_REG5 0x2e
+
+#define MMA8452_MAX_REG 0x31
 
 #define MMA8452_STATUS_DRDY (BIT(2) | BIT(1) | BIT(0))
 
@@ -44,6 +66,10 @@
 #define MMA8452_DATA_CFG_FS_2G 0
 #define MMA8452_DATA_CFG_FS_4G 1
 #define MMA8452_DATA_CFG_FS_8G 2
+#define MMA8452_DATA_CFG_HPF_MASK BIT(4)
+
+#define MMA8452_INT_DRDY	BIT(0)
+#define MMA8452_INT_TRANS	BIT(5)
 
 #define MMA8452_DEVICE_ID 0x2a
 
@@ -106,6 +132,12 @@ static int mma8452_get_int_plus_micros_index(const int (*vals)[2], int n,
 	return -EINVAL;
 }
 
+static int mma8452_get_odr_index(struct mma8452_data *data)
+{
+	return (data->ctrl_reg1 & MMA8452_CTRL_DR_MASK) >>
+			MMA8452_CTRL_DR_SHIFT;
+}
+
 static const int mma8452_samp_freq[8][2] = {
 	{800, 0}, {400, 0}, {200, 0}, {100, 0}, {50, 0}, {12, 500000},
 	{6, 250000}, {1, 560000}
@@ -121,6 +153,30 @@ static const int mma8452_scales[3][2] = {
 	{0, 9577}, {0, 19154}, {0, 38307}
 };
 
+/* Datasheet table 35  (step time vs sample frequency) */
+static const int mma8452_transient_time_step_us[8] = {
+	1250,
+	2500,
+	5000,
+	10000,
+	20000,
+	20000,
+	20000,
+	20000
+};
+
+/* Datasheet table 18 (normal mode) */
+static const int mma8452_hp_filter_cutoff[8][4][2] = {
+	{ {16, 0}, {8, 0}, {4, 0}, {2, 0} },		/* 800 Hz sample */
+	{ {16, 0}, {8, 0}, {4, 0}, {2, 0} },		/* 400 Hz sample */
+	{ {8, 0}, {4, 0}, {2, 0}, {1, 0} },		/* 200 Hz sample */
+	{ {4, 0}, {2, 0}, {1, 0}, {0, 500000} },	/* 100 Hz sample */
+	{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} },	/* 50 Hz sample */
+	{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} },	/* 12.5 Hz sample */
+	{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} },	/* 6.25 Hz sample */
+	{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} }	/* 1.56 Hz sample */
+};
+
 static ssize_t mma8452_show_samp_freq_avail(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
@@ -135,9 +191,23 @@ static ssize_t mma8452_show_scale_avail(struct device *dev,
 		ARRAY_SIZE(mma8452_scales));
 }
 
+static ssize_t mma8452_show_hp_cutoff_avail(struct device *dev,
+					    struct device_attribute *attr,
+					    char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int i = mma8452_get_odr_index(data);
+
+	return mma8452_show_int_plus_micros(buf, mma8452_hp_filter_cutoff[i],
+		ARRAY_SIZE(mma8452_hp_filter_cutoff[0]));
+}
+
 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(mma8452_show_samp_freq_avail);
 static IIO_DEVICE_ATTR(in_accel_scale_available, S_IRUGO,
 	mma8452_show_scale_avail, NULL, 0);
+static IIO_DEVICE_ATTR(in_accel_filter_high_pass_3db_frequency_available,
+			S_IRUGO, mma8452_show_hp_cutoff_avail, NULL, 0);
 
 static int mma8452_get_samp_freq_index(struct mma8452_data *data,
 	int val, int val2)
@@ -153,6 +223,31 @@ static int mma8452_get_scale_index(struct mma8452_data *data,
 		ARRAY_SIZE(mma8452_scales), val, val2);
 }
 
+static int mma8452_get_hp_filter_index(struct mma8452_data *data,
+				       int val, int val2)
+{
+	int i = mma8452_get_odr_index(data);
+
+	return mma8452_get_int_plus_micros_index(mma8452_hp_filter_cutoff[i],
+		ARRAY_SIZE(mma8452_scales[0]), val, val2);
+}
+
+static int mma8452_read_hp_filter(struct mma8452_data *data, int *hz, int *uHz)
+{
+	int i, ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, MMA8452_HP_FILTER_CUTOFF);
+	if (ret < 0)
+		return ret;
+
+	i = mma8452_get_odr_index(data);
+	ret &= MMA8452_HP_FILTER_CUTOFF_SEL_MASK;
+	*hz = mma8452_hp_filter_cutoff[i][ret][0];
+	*uHz = mma8452_hp_filter_cutoff[i][ret][1];
+
+	return 0;
+}
+
 static int mma8452_read_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
 			    int *val, int *val2, long mask)
@@ -180,8 +275,7 @@ static int mma8452_read_raw(struct iio_dev *indio_dev,
 		*val2 = mma8452_scales[i][1];
 		return IIO_VAL_INT_PLUS_MICRO;
 	case IIO_CHAN_INFO_SAMP_FREQ:
-		i = (data->ctrl_reg1 & MMA8452_CTRL_DR_MASK) >>
-			MMA8452_CTRL_DR_SHIFT;
+		i = mma8452_get_odr_index(data);
 		*val = mma8452_samp_freq[i][0];
 		*val2 = mma8452_samp_freq[i][1];
 		return IIO_VAL_INT_PLUS_MICRO;
@@ -192,6 +286,16 @@ static int mma8452_read_raw(struct iio_dev *indio_dev,
 			return ret;
 		*val = sign_extend32(ret, 7);
 		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+		if (data->data_cfg & MMA8452_DATA_CFG_HPF_MASK) {
+			ret = mma8452_read_hp_filter(data, val, val2);
+			if (ret < 0)
+				return ret;
+		} else {
+			*val = 0;
+			*val2 = 0;
+		}
+		return IIO_VAL_INT_PLUS_MICRO;
 	}
 	return -EINVAL;
 }
@@ -233,12 +337,31 @@ fail:
 	return ret;
 }
 
+static int mma8452_set_hp_filter_frequency(struct mma8452_data *data,
+					   int val, int val2)
+{
+	int i, reg;
+
+	i = mma8452_get_hp_filter_index(data, val, val2);
+	if (i < 0)
+		return -EINVAL;
+
+	reg = i2c_smbus_read_byte_data(data->client,
+				       MMA8452_HP_FILTER_CUTOFF);
+	if (reg < 0)
+		return reg;
+	reg &= ~MMA8452_HP_FILTER_CUTOFF_SEL_MASK;
+	reg |= i;
+
+	return mma8452_change_config(data, MMA8452_HP_FILTER_CUTOFF, reg);
+}
+
 static int mma8452_write_raw(struct iio_dev *indio_dev,
 			     struct iio_chan_spec const *chan,
 			     int val, int val2, long mask)
 {
 	struct mma8452_data *data = iio_priv(indio_dev);
-	int i;
+	int i, ret;
 
 	if (iio_buffer_enabled(indio_dev))
 		return -EBUSY;
@@ -266,11 +389,217 @@ static int mma8452_write_raw(struct iio_dev *indio_dev,
 			return -EINVAL;
 		return mma8452_change_config(data, MMA8452_OFF_X +
 			chan->scan_index, val);
+
+	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+		if (val == 0 && val2 == 0) {
+			data->data_cfg &= ~MMA8452_DATA_CFG_HPF_MASK;
+		} else {
+			data->data_cfg |= MMA8452_DATA_CFG_HPF_MASK;
+			ret = mma8452_set_hp_filter_frequency(data, val, val2);
+			if (ret < 0)
+				return ret;
+		}
+		return mma8452_change_config(data, MMA8452_DATA_CFG,
+						data->data_cfg);
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int mma8452_read_thresh(struct iio_dev *indio_dev,
+			       const struct iio_chan_spec *chan,
+			       enum iio_event_type type,
+			       enum iio_event_direction dir,
+			       enum iio_event_info info,
+			       int *val, int *val2)
+{
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int ret, us;
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		ret = i2c_smbus_read_byte_data(data->client,
+					       MMA8452_TRANSIENT_THS);
+		if (ret < 0)
+			return ret;
+
+		*val = ret & MMA8452_TRANSIENT_THS_MASK;
+		return IIO_VAL_INT;
+
+	case IIO_EV_INFO_PERIOD:
+		ret = i2c_smbus_read_byte_data(data->client,
+					       MMA8452_TRANSIENT_COUNT);
+		if (ret < 0)
+			return ret;
+
+		us = ret * mma8452_transient_time_step_us[
+				mma8452_get_odr_index(data)];
+		*val = us / USEC_PER_SEC;
+		*val2 = us % USEC_PER_SEC;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	case IIO_EV_INFO_HIGH_PASS_FILTER_3DB:
+		ret = i2c_smbus_read_byte_data(data->client,
+					       MMA8452_TRANSIENT_CFG);
+		if (ret < 0)
+			return ret;
+
+		if (ret & MMA8452_TRANSIENT_CFG_HPF_BYP) {
+			*val = 0;
+			*val2 = 0;
+		} else {
+			ret = mma8452_read_hp_filter(data, val, val2);
+			if (ret < 0)
+				return ret;
+		}
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int mma8452_write_thresh(struct iio_dev *indio_dev,
+				const struct iio_chan_spec *chan,
+				enum iio_event_type type,
+				enum iio_event_direction dir,
+				enum iio_event_info info,
+				int val, int val2)
+{
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int ret, reg, steps;
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		return mma8452_change_config(data, MMA8452_TRANSIENT_THS,
+					     val & MMA8452_TRANSIENT_THS_MASK);
+
+	case IIO_EV_INFO_PERIOD:
+		steps = (val * USEC_PER_SEC + val2) /
+				mma8452_transient_time_step_us[
+					mma8452_get_odr_index(data)];
+
+		if (steps > 0xff)
+			return -EINVAL;
+
+		return mma8452_change_config(data, MMA8452_TRANSIENT_COUNT,
+					     steps);
+	case IIO_EV_INFO_HIGH_PASS_FILTER_3DB:
+		reg = i2c_smbus_read_byte_data(data->client,
+					       MMA8452_TRANSIENT_CFG);
+		if (reg < 0)
+			return reg;
+
+		if (val == 0 && val2 == 0) {
+			reg |= MMA8452_TRANSIENT_CFG_HPF_BYP;
+		} else {
+			reg &= ~MMA8452_TRANSIENT_CFG_HPF_BYP;
+			ret = mma8452_set_hp_filter_frequency(data, val, val2);
+			if (ret < 0)
+				return ret;
+		}
+		return mma8452_change_config(data, MMA8452_TRANSIENT_CFG, reg);
+
 	default:
 		return -EINVAL;
 	}
 }
 
+static int mma8452_read_event_config(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir)
+{
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_CFG);
+	if (ret < 0)
+		return ret;
+
+	return ret & MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index) ? 1 : 0;
+}
+
+static int mma8452_write_event_config(struct iio_dev *indio_dev,
+				      const struct iio_chan_spec *chan,
+				      enum iio_event_type type,
+				      enum iio_event_direction dir,
+				      int state)
+{
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int val;
+
+	val = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_CFG);
+	if (val < 0)
+		return val;
+
+	if (state)
+		val |= MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index);
+	else
+		val &= ~MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index);
+
+	val |= MMA8452_TRANSIENT_CFG_ELE;
+
+	return mma8452_change_config(data, MMA8452_TRANSIENT_CFG, val);
+}
+
+static void mma8452_transient_interrupt(struct iio_dev *indio_dev)
+{
+	struct mma8452_data *data = iio_priv(indio_dev);
+	s64 ts = iio_get_time_ns();
+	int src;
+
+	src = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_SRC);
+	if (src < 0)
+		return;
+
+	if (src & MMA8452_TRANSIENT_SRC_XTRANSE)
+		iio_push_event(indio_dev,
+			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_X,
+						  IIO_EV_TYPE_THRESH,
+						  IIO_EV_DIR_RISING),
+			       ts);
+
+	if (src & MMA8452_TRANSIENT_SRC_YTRANSE)
+		iio_push_event(indio_dev,
+			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_Y,
+						  IIO_EV_TYPE_THRESH,
+						  IIO_EV_DIR_RISING),
+			       ts);
+
+	if (src & MMA8452_TRANSIENT_SRC_ZTRANSE)
+		iio_push_event(indio_dev,
+			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_Z,
+						  IIO_EV_TYPE_THRESH,
+						  IIO_EV_DIR_RISING),
+			       ts);
+}
+
+static irqreturn_t mma8452_interrupt(int irq, void *p)
+{
+	struct iio_dev *indio_dev = p;
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int ret = IRQ_NONE;
+	int src;
+
+	src = i2c_smbus_read_byte_data(data->client, MMA8452_INT_SRC);
+	if (src < 0)
+		return IRQ_NONE;
+
+	if (src & MMA8452_INT_DRDY) {
+		iio_trigger_poll_chained(indio_dev->trig);
+		ret = IRQ_HANDLED;
+	}
+
+	if (src & MMA8452_INT_TRANS) {
+		mma8452_transient_interrupt(indio_dev);
+		ret = IRQ_HANDLED;
+	}
+
+	return ret;
+}
+
 static irqreturn_t mma8452_trigger_handler(int irq, void *p)
 {
 	struct iio_poll_func *pf = p;
@@ -291,6 +620,55 @@ done:
 	return IRQ_HANDLED;
 }
 
+static int mma8452_reg_access_dbg(struct iio_dev *indio_dev,
+				  unsigned reg, unsigned writeval,
+				  unsigned *readval)
+{
+	int ret;
+	struct mma8452_data *data = iio_priv(indio_dev);
+
+	if (reg > MMA8452_MAX_REG)
+		return -EINVAL;
+
+	if (!readval)
+		return mma8452_change_config(data, reg, writeval);
+
+	ret = i2c_smbus_read_byte_data(data->client, reg);
+	if (ret < 0)
+		return ret;
+
+	*readval = ret;
+
+	return 0;
+}
+
+static const struct iio_event_spec mma8452_transient_event[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
+					BIT(IIO_EV_INFO_PERIOD) |
+					BIT(IIO_EV_INFO_HIGH_PASS_FILTER_3DB)
+	},
+};
+
+/*
+ * Threshold is configured in fixed 8G/127 steps regardless of
+ * currently selected scale for measurement.
+ */
+static IIO_CONST_ATTR_NAMED(accel_transient_scale, in_accel_scale, "0.617742");
+
+static struct attribute *mma8452_event_attributes[] = {
+	&iio_const_attr_accel_transient_scale.dev_attr.attr,
+	NULL,
+};
+
+static struct attribute_group mma8452_event_attribute_group = {
+	.attrs = mma8452_event_attributes,
+	.name = "events",
+};
+
 #define MMA8452_CHANNEL(axis, idx) { \
 	.type = IIO_ACCEL, \
 	.modified = 1, \
@@ -298,7 +676,8 @@ done:
 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
 		BIT(IIO_CHAN_INFO_CALIBBIAS), \
 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
-		BIT(IIO_CHAN_INFO_SCALE), \
+		BIT(IIO_CHAN_INFO_SCALE) | \
+		BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \
 	.scan_index = idx, \
 	.scan_type = { \
 		.sign = 's', \
@@ -307,6 +686,8 @@ done:
 		.shift = 4, \
 		.endianness = IIO_BE, \
 	}, \
+	.event_spec = mma8452_transient_event, \
+	.num_event_specs = ARRAY_SIZE(mma8452_transient_event), \
 }
 
 static const struct iio_chan_spec mma8452_channels[] = {
@@ -319,6 +700,7 @@ static const struct iio_chan_spec mma8452_channels[] = {
 static struct attribute *mma8452_attributes[] = {
 	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 	&iio_dev_attr_in_accel_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_accel_filter_high_pass_3db_frequency_available.dev_attr.attr,
 	NULL
 };
 
@@ -330,11 +712,107 @@ static const struct iio_info mma8452_info = {
 	.attrs = &mma8452_group,
 	.read_raw = &mma8452_read_raw,
 	.write_raw = &mma8452_write_raw,
+	.event_attrs = &mma8452_event_attribute_group,
+	.read_event_value = &mma8452_read_thresh,
+	.write_event_value = &mma8452_write_thresh,
+	.read_event_config = &mma8452_read_event_config,
+	.write_event_config = &mma8452_write_event_config,
+	.debugfs_reg_access = &mma8452_reg_access_dbg,
 	.driver_module = THIS_MODULE,
 };
 
 static const unsigned long mma8452_scan_masks[] = {0x7, 0};
 
+static int mma8452_data_rdy_trigger_set_state(struct iio_trigger *trig,
+					      bool state)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct mma8452_data *data = iio_priv(indio_dev);
+	int reg;
+
+	reg = i2c_smbus_read_byte_data(data->client, MMA8452_CTRL_REG4);
+	if (reg < 0)
+		return reg;
+
+	if (state)
+		reg |= MMA8452_INT_DRDY;
+	else
+		reg &= ~MMA8452_INT_DRDY;
+
+	return mma8452_change_config(data, MMA8452_CTRL_REG4, reg);
+}
+
+static int mma8452_validate_device(struct iio_trigger *trig,
+				   struct iio_dev *indio_dev)
+{
+	struct iio_dev *indio = iio_trigger_get_drvdata(trig);
+
+	if (indio != indio_dev)
+		return -EINVAL;
+
+	return 0;
+}
+
+static const struct iio_trigger_ops mma8452_trigger_ops = {
+	.set_trigger_state = mma8452_data_rdy_trigger_set_state,
+	.validate_device = mma8452_validate_device,
+	.owner = THIS_MODULE,
+};
+
+static int mma8452_trigger_setup(struct iio_dev *indio_dev)
+{
+	struct mma8452_data *data = iio_priv(indio_dev);
+	struct iio_trigger *trig;
+	int ret;
+
+	trig = devm_iio_trigger_alloc(&data->client->dev, "%s-dev%d",
+				      indio_dev->name,
+				      indio_dev->id);
+	if (!trig)
+		return -ENOMEM;
+
+	trig->dev.parent = &data->client->dev;
+	trig->ops = &mma8452_trigger_ops;
+	iio_trigger_set_drvdata(trig, indio_dev);
+
+	ret = iio_trigger_register(trig);
+	if (ret)
+		return ret;
+
+	indio_dev->trig = trig;
+	return 0;
+}
+
+static void mma8452_trigger_cleanup(struct iio_dev *indio_dev)
+{
+	if (indio_dev->trig)
+		iio_trigger_unregister(indio_dev->trig);
+}
+
+static int mma8452_reset(struct i2c_client *client)
+{
+	int i;
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client,	MMA8452_CTRL_REG2,
+					MMA8452_CTRL_REG2_RST);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < 10; i++) {
+		usleep_range(100, 200);
+		ret = i2c_smbus_read_byte_data(client, MMA8452_CTRL_REG2);
+		if (ret == -EIO)
+			continue; /* I2C comm reset */
+		if (ret < 0)
+			return ret;
+		if (!(ret & MMA8452_CTRL_REG2_RST))
+			return 0;
+	}
+
+	return -ETIMEDOUT;
+}
+
 static int mma8452_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
@@ -365,10 +843,7 @@ static int mma8452_probe(struct i2c_client *client,
 	indio_dev->num_channels = ARRAY_SIZE(mma8452_channels);
 	indio_dev->available_scan_masks = mma8452_scan_masks;
 
-	data->ctrl_reg1 = MMA8452_CTRL_ACTIVE |
-		(MMA8452_CTRL_DR_DEFAULT << MMA8452_CTRL_DR_SHIFT);
-	ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG1,
-		data->ctrl_reg1);
+	ret = mma8452_reset(client);
 	if (ret < 0)
 		return ret;
 
@@ -378,18 +853,77 @@ static int mma8452_probe(struct i2c_client *client,
 	if (ret < 0)
 		return ret;
 
+	/*
+	 * By default set transient threshold to max to avoid events if
+	 * enabling without configuring threshold.
+	 */
+	ret = i2c_smbus_write_byte_data(client, MMA8452_TRANSIENT_THS,
+					MMA8452_TRANSIENT_THS_MASK);
+	if (ret < 0)
+		return ret;
+
+	if (client->irq) {
+		/*
+		 * Although we enable the transient interrupt source once and
+		 * for all here the transient event detection itself is not
+		 * enabled until userspace asks for it by
+		 * mma8452_write_event_config()
+		 */
+		int supported_interrupts = MMA8452_INT_DRDY | MMA8452_INT_TRANS;
+		int enabled_interrupts = MMA8452_INT_TRANS;
+
+		/* Assume wired to INT1 pin */
+		ret = i2c_smbus_write_byte_data(client,
+						MMA8452_CTRL_REG5,
+						supported_interrupts);
+		if (ret < 0)
+			return ret;
+
+		ret = i2c_smbus_write_byte_data(client,
+						MMA8452_CTRL_REG4,
+						enabled_interrupts);
+		if (ret < 0)
+			return ret;
+
+		ret = mma8452_trigger_setup(indio_dev);
+		if (ret < 0)
+			return ret;
+	}
+
+	data->ctrl_reg1 = MMA8452_CTRL_ACTIVE |
+		(MMA8452_CTRL_DR_DEFAULT << MMA8452_CTRL_DR_SHIFT);
+	ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG1,
+					data->ctrl_reg1);
+	if (ret < 0)
+		goto trigger_cleanup;
+
 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
 		mma8452_trigger_handler, NULL);
 	if (ret < 0)
-		return ret;
+		goto trigger_cleanup;
+
+	if (client->irq) {
+		ret = devm_request_threaded_irq(&client->dev,
+						client->irq,
+						NULL, mma8452_interrupt,
+						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						client->name, indio_dev);
+		if (ret)
+			goto buffer_cleanup;
+	}
 
 	ret = iio_device_register(indio_dev);
 	if (ret < 0)
 		goto buffer_cleanup;
+
 	return 0;
 
 buffer_cleanup:
 	iio_triggered_buffer_cleanup(indio_dev);
+
+trigger_cleanup:
+	mma8452_trigger_cleanup(indio_dev);
+
 	return ret;
 }
 
@@ -399,6 +933,7 @@ static int mma8452_remove(struct i2c_client *client)
 
 	iio_device_unregister(indio_dev);
 	iio_triggered_buffer_cleanup(indio_dev);
+	mma8452_trigger_cleanup(indio_dev);
 	mma8452_standby(iio_priv(indio_dev));
 
 	return 0;
diff --git a/drivers/iio/accel/mma9551_core.c b/drivers/iio/accel/mma9551_core.c
index c6d5a3a40b60..2fd2a995686b 100644
--- a/drivers/iio/accel/mma9551_core.c
+++ b/drivers/iio/accel/mma9551_core.c
@@ -374,7 +374,7 @@ EXPORT_SYMBOL(mma9551_read_status_word);
  * @app_id:	Application ID
  * @reg:	Application register
  * @len:	Length of array to read in bytes
- * @val:	Array of words to read
+ * @buf:	Array of words to read
  *
  * Read multiple configuration registers (word-sized registers).
  *
@@ -414,7 +414,7 @@ EXPORT_SYMBOL(mma9551_read_config_words);
  * @app_id:	Application ID
  * @reg:	Application register
  * @len:	Length of array to read in bytes
- * @val:	Array of words to read
+ * @buf:	Array of words to read
  *
  * Read multiple status registers (word-sized registers).
  *
@@ -454,7 +454,7 @@ EXPORT_SYMBOL(mma9551_read_status_words);
  * @app_id:	Application ID
  * @reg:	Application register
  * @len:	Length of array to write in bytes
- * @val:	Array of words to write
+ * @buf:	Array of words to write
  *
  * Write multiple configuration registers (word-sized registers).
  *
@@ -800,7 +800,7 @@ EXPORT_SYMBOL(mma9551_read_accel_scale);
  */
 int mma9551_app_reset(struct i2c_client *client, u32 app_mask)
 {
-	return mma9551_write_config_byte(client, MMA9551_APPID_RCS,
+	return mma9551_write_config_byte(client, MMA9551_APPID_RSC,
 					 MMA9551_RSC_RESET +
 					 MMA9551_RSC_OFFSET(app_mask),
 					 MMA9551_RSC_VAL(app_mask));
diff --git a/drivers/iio/accel/mma9551_core.h b/drivers/iio/accel/mma9551_core.h
index edaa56b1078e..79939e40805a 100644
--- a/drivers/iio/accel/mma9551_core.h
+++ b/drivers/iio/accel/mma9551_core.h
@@ -22,7 +22,7 @@
 #define MMA9551_APPID_TILT		0x0B
 #define MMA9551_APPID_SLEEP_WAKE	0x12
 #define MMA9551_APPID_PEDOMETER	        0x15
-#define MMA9551_APPID_RCS		0x17
+#define MMA9551_APPID_RSC		0x17
 #define MMA9551_APPID_NONE		0xff
 
 /* Reset/Suspend/Clear application app masks */
diff --git a/drivers/iio/accel/mma9553.c b/drivers/iio/accel/mma9553.c
index 365a109aaaef..8bfc61824fb2 100644
--- a/drivers/iio/accel/mma9553.c
+++ b/drivers/iio/accel/mma9553.c
@@ -63,8 +63,8 @@
 #define MMA9553_MASK_STATUS_STEPCHG		BIT(13)
 #define MMA9553_MASK_STATUS_ACTCHG		BIT(12)
 #define MMA9553_MASK_STATUS_SUSP		BIT(11)
-#define MMA9553_MASK_STATUS_ACTIVITY		(BIT(10) | BIT(9) | BIT(8))
-#define MMA9553_MASK_STATUS_VERSION		0x00FF
+#define MMA9553_MASK_STATUS_ACTIVITY		GENMASK(10, 8)
+#define MMA9553_MASK_STATUS_VERSION		GENMASK(7, 0)
 
 #define MMA9553_REG_STEPCNT			0x02
 #define MMA9553_REG_DISTANCE			0x04
@@ -76,14 +76,15 @@
 #define MMA9553_DEFAULT_GPIO_PIN	mma9551_gpio6
 #define MMA9553_DEFAULT_GPIO_POLARITY	0
 
-/* Bitnum used for gpio configuration = bit number in high status byte */
-#define STATUS_TO_BITNUM(bit)		(ffs(bit) - 9)
+/* Bitnum used for GPIO configuration = bit number in high status byte */
+#define MMA9553_STATUS_TO_BITNUM(bit)	(ffs(bit) - 9)
+#define MMA9553_MAX_BITNUM		MMA9553_STATUS_TO_BITNUM(BIT(16))
 
 #define MMA9553_DEFAULT_SAMPLE_RATE	30	/* Hz */
 
 /*
  * The internal activity level must be stable for ACTTHD samples before
- * ACTIVITY is updated.The ACTIVITY variable contains the current activity
+ * ACTIVITY is updated. The ACTIVITY variable contains the current activity
  * level and is updated every time a step is detected or once a second
  * if there are no steps.
  */
@@ -351,11 +352,11 @@ static int mma9553_conf_gpio(struct mma9553_data *data)
 	 * This bit is the logical OR of the SUSPCHG, STEPCHG, and ACTCHG flags.
 	 */
 	if (activity_enabled && ev_step_detect->enabled)
-		bitnum = STATUS_TO_BITNUM(MMA9553_MASK_STATUS_MRGFL);
+		bitnum = MMA9553_STATUS_TO_BITNUM(MMA9553_MASK_STATUS_MRGFL);
 	else if (ev_step_detect->enabled)
-		bitnum = STATUS_TO_BITNUM(MMA9553_MASK_STATUS_STEPCHG);
+		bitnum = MMA9553_STATUS_TO_BITNUM(MMA9553_MASK_STATUS_STEPCHG);
 	else if (activity_enabled)
-		bitnum = STATUS_TO_BITNUM(MMA9553_MASK_STATUS_ACTCHG);
+		bitnum = MMA9553_STATUS_TO_BITNUM(MMA9553_MASK_STATUS_ACTCHG);
 	else			/* Reset */
 		appid = MMA9551_APPID_NONE;
 
@@ -363,9 +364,12 @@ static int mma9553_conf_gpio(struct mma9553_data *data)
 		return 0;
 
 	/* Save initial values for activity and stepcnt */
-	if (activity_enabled || ev_step_detect->enabled)
-		mma9553_read_activity_stepcnt(data, &data->activity,
-					      &data->stepcnt);
+	if (activity_enabled || ev_step_detect->enabled) {
+		ret = mma9553_read_activity_stepcnt(data, &data->activity,
+						    &data->stepcnt);
+		if (ret < 0)
+			return ret;
+	}
 
 	ret = mma9551_gpio_config(data->client,
 				  MMA9553_DEFAULT_GPIO_PIN,
@@ -396,13 +400,13 @@ static int mma9553_init(struct mma9553_data *data)
 				      sizeof(data->conf), (u16 *) &data->conf);
 	if (ret < 0) {
 		dev_err(&data->client->dev,
-			"device is not MMA9553L: failed to read cfg regs\n");
+			"failed to read configuration registers\n");
 		return ret;
 	}
 
 
-	/* Reset gpio */
-	data->gpio_bitnum = -1;
+	/* Reset GPIO */
+	data->gpio_bitnum = MMA9553_MAX_BITNUM;
 	ret = mma9553_conf_gpio(data);
 	if (ret < 0)
 		return ret;
@@ -436,6 +440,32 @@ static int mma9553_init(struct mma9553_data *data)
 	return mma9551_set_device_state(data->client, true);
 }
 
+static int mma9553_read_status_word(struct mma9553_data *data, u16 reg,
+				    u16 *tmp)
+{
+	bool powered_on;
+	int ret;
+
+	/*
+	 * The HW only counts steps and other dependent
+	 * parameters (speed, distance, calories, activity)
+	 * if power is on (from enabling an event or the
+	 * step counter).
+	 */
+	powered_on = mma9553_is_any_event_enabled(data, false, 0) ||
+		     data->stepcnt_enabled;
+	if (!powered_on) {
+		dev_err(&data->client->dev, "No channels enabled\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&data->mutex);
+	ret = mma9551_read_status_word(data->client, MMA9551_APPID_PEDOMETER,
+				       reg, tmp);
+	mutex_unlock(&data->mutex);
+	return ret;
+}
+
 static int mma9553_read_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
 			    int *val, int *val2, long mask)
@@ -444,69 +474,30 @@ static int mma9553_read_raw(struct iio_dev *indio_dev,
 	int ret;
 	u16 tmp;
 	u8 activity;
-	bool powered_on;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_PROCESSED:
 		switch (chan->type) {
 		case IIO_STEPS:
-			/*
-			 * The HW only counts steps and other dependent
-			 * parameters (speed, distance, calories, activity)
-			 * if power is on (from enabling an event or the
-			 * step counter */
-			powered_on =
-			    mma9553_is_any_event_enabled(data, false, 0) ||
-			    data->stepcnt_enabled;
-			if (!powered_on) {
-				dev_err(&data->client->dev,
-					"No channels enabled\n");
-				return -EINVAL;
-			}
-			mutex_lock(&data->mutex);
-			ret = mma9551_read_status_word(data->client,
-						       MMA9551_APPID_PEDOMETER,
+			ret = mma9553_read_status_word(data,
 						       MMA9553_REG_STEPCNT,
 						       &tmp);
-			mutex_unlock(&data->mutex);
 			if (ret < 0)
 				return ret;
 			*val = tmp;
 			return IIO_VAL_INT;
 		case IIO_DISTANCE:
-			powered_on =
-			    mma9553_is_any_event_enabled(data, false, 0) ||
-			    data->stepcnt_enabled;
-			if (!powered_on) {
-				dev_err(&data->client->dev,
-					"No channels enabled\n");
-				return -EINVAL;
-			}
-			mutex_lock(&data->mutex);
-			ret = mma9551_read_status_word(data->client,
-						       MMA9551_APPID_PEDOMETER,
+			ret = mma9553_read_status_word(data,
 						       MMA9553_REG_DISTANCE,
 						       &tmp);
-			mutex_unlock(&data->mutex);
 			if (ret < 0)
 				return ret;
 			*val = tmp;
 			return IIO_VAL_INT;
 		case IIO_ACTIVITY:
-			powered_on =
-			    mma9553_is_any_event_enabled(data, false, 0) ||
-			    data->stepcnt_enabled;
-			if (!powered_on) {
-				dev_err(&data->client->dev,
-					"No channels enabled\n");
-				return -EINVAL;
-			}
-			mutex_lock(&data->mutex);
-			ret = mma9551_read_status_word(data->client,
-						       MMA9551_APPID_PEDOMETER,
+			ret = mma9553_read_status_word(data,
 						       MMA9553_REG_STATUS,
 						       &tmp);
-			mutex_unlock(&data->mutex);
 			if (ret < 0)
 				return ret;
 
@@ -531,38 +522,17 @@ static int mma9553_read_raw(struct iio_dev *indio_dev,
 		case IIO_VELOCITY:	/* m/h */
 			if (chan->channel2 != IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z)
 				return -EINVAL;
-			powered_on =
-			    mma9553_is_any_event_enabled(data, false, 0) ||
-			    data->stepcnt_enabled;
-			if (!powered_on) {
-				dev_err(&data->client->dev,
-					"No channels enabled\n");
-				return -EINVAL;
-			}
-			mutex_lock(&data->mutex);
-			ret = mma9551_read_status_word(data->client,
-						       MMA9551_APPID_PEDOMETER,
-						       MMA9553_REG_SPEED, &tmp);
-			mutex_unlock(&data->mutex);
+			ret = mma9553_read_status_word(data,
+						       MMA9553_REG_SPEED,
+						       &tmp);
 			if (ret < 0)
 				return ret;
 			*val = tmp;
 			return IIO_VAL_INT;
 		case IIO_ENERGY:	/* Cal or kcal */
-			powered_on =
-			    mma9553_is_any_event_enabled(data, false, 0) ||
-			    data->stepcnt_enabled;
-			if (!powered_on) {
-				dev_err(&data->client->dev,
-					"No channels enabled\n");
-				return -EINVAL;
-			}
-			mutex_lock(&data->mutex);
-			ret = mma9551_read_status_word(data->client,
-						       MMA9551_APPID_PEDOMETER,
+			ret = mma9553_read_status_word(data,
 						       MMA9553_REG_CALORIES,
 						       &tmp);
-			mutex_unlock(&data->mutex);
 			if (ret < 0)
 				return ret;
 			*val = tmp;
@@ -789,7 +759,7 @@ static int mma9553_write_event_config(struct iio_dev *indio_dev,
 
 	mutex_unlock(&data->mutex);
 
-	return ret;
+	return 0;
 
 err_conf_gpio:
 	if (state) {
@@ -897,7 +867,7 @@ static int mma9553_get_calibgender_mode(struct iio_dev *indio_dev,
 	gender = mma9553_get_bits(data->conf.filter, MMA9553_MASK_CONF_MALE);
 	/*
 	 * HW expects 0 for female and 1 for male,
-	 * while iio index is 0 for male and 1 for female
+	 * while iio index is 0 for male and 1 for female.
 	 */
 	return !gender;
 }
@@ -944,11 +914,11 @@ static const struct iio_event_spec mma9553_activity_events[] = {
 	},
 };
 
-static const char * const calibgender_modes[] = { "male", "female" };
+static const char * const mma9553_calibgender_modes[] = { "male", "female" };
 
 static const struct iio_enum mma9553_calibgender_enum = {
-	.items = calibgender_modes,
-	.num_items = ARRAY_SIZE(calibgender_modes),
+	.items = mma9553_calibgender_modes,
+	.num_items = ARRAY_SIZE(mma9553_calibgender_modes),
 	.get = mma9553_get_calibgender_mode,
 	.set = mma9553_set_calibgender_mode,
 };
@@ -1110,16 +1080,16 @@ static int mma9553_gpio_probe(struct i2c_client *client)
 
 	dev = &client->dev;
 
-	/* data ready gpio interrupt pin */
+	/* data ready GPIO interrupt pin */
 	gpio = devm_gpiod_get_index(dev, MMA9553_GPIO_NAME, 0, GPIOD_IN);
 	if (IS_ERR(gpio)) {
-		dev_err(dev, "acpi gpio get index failed\n");
+		dev_err(dev, "ACPI GPIO get index failed\n");
 		return PTR_ERR(gpio);
 	}
 
 	ret = gpiod_to_irq(gpio);
 
-	dev_dbg(dev, "gpio resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
+	dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
 
 	return ret;
 }
diff --git a/drivers/iio/accel/st_accel.h b/drivers/iio/accel/st_accel.h
index 7ee9724b1428..aa1001931d0c 100644
--- a/drivers/iio/accel/st_accel.h
+++ b/drivers/iio/accel/st_accel.h
@@ -20,6 +20,7 @@
 #define LSM330D_ACCEL_DEV_NAME		"lsm330d_accel"
 #define LSM330DL_ACCEL_DEV_NAME		"lsm330dl_accel"
 #define LSM330DLC_ACCEL_DEV_NAME	"lsm330dlc_accel"
+#define LIS331DL_ACCEL_DEV_NAME		"lis331dl_accel"
 #define LIS331DLH_ACCEL_DEV_NAME	"lis331dlh"
 #define LSM303DL_ACCEL_DEV_NAME		"lsm303dl_accel"
 #define LSM303DLH_ACCEL_DEV_NAME	"lsm303dlh_accel"
diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
index 211b13271c61..4002e6410444 100644
--- a/drivers/iio/accel/st_accel_core.c
+++ b/drivers/iio/accel/st_accel_core.c
@@ -153,6 +153,44 @@
 #define ST_ACCEL_4_IG1_EN_MASK			0x08
 #define ST_ACCEL_4_MULTIREAD_BIT		true
 
+/* CUSTOM VALUES FOR SENSOR 5 */
+#define ST_ACCEL_5_WAI_EXP			0x3b
+#define ST_ACCEL_5_ODR_ADDR			0x20
+#define ST_ACCEL_5_ODR_MASK			0x80
+#define ST_ACCEL_5_ODR_AVL_100HZ_VAL		0x00
+#define ST_ACCEL_5_ODR_AVL_400HZ_VAL		0x01
+#define ST_ACCEL_5_PW_ADDR			0x20
+#define ST_ACCEL_5_PW_MASK			0x40
+#define ST_ACCEL_5_FS_ADDR			0x20
+#define ST_ACCEL_5_FS_MASK			0x20
+#define ST_ACCEL_5_FS_AVL_2_VAL			0X00
+#define ST_ACCEL_5_FS_AVL_8_VAL			0X01
+/* TODO: check these resulting gain settings, these are not in the datsheet */
+#define ST_ACCEL_5_FS_AVL_2_GAIN		IIO_G_TO_M_S_2(18000)
+#define ST_ACCEL_5_FS_AVL_8_GAIN		IIO_G_TO_M_S_2(72000)
+#define ST_ACCEL_5_DRDY_IRQ_ADDR		0x22
+#define ST_ACCEL_5_DRDY_IRQ_INT1_MASK		0x04
+#define ST_ACCEL_5_DRDY_IRQ_INT2_MASK		0x20
+#define ST_ACCEL_5_IG1_EN_ADDR			0x21
+#define ST_ACCEL_5_IG1_EN_MASK			0x08
+#define ST_ACCEL_5_MULTIREAD_BIT		false
+
+static const struct iio_chan_spec st_accel_8bit_channels[] = {
+	ST_SENSORS_LSM_CHANNELS(IIO_ACCEL,
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+			ST_SENSORS_SCAN_X, 1, IIO_MOD_X, 's', IIO_LE, 8, 8,
+			ST_ACCEL_DEFAULT_OUT_X_L_ADDR+1),
+	ST_SENSORS_LSM_CHANNELS(IIO_ACCEL,
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+			ST_SENSORS_SCAN_Y, 1, IIO_MOD_Y, 's', IIO_LE, 8, 8,
+			ST_ACCEL_DEFAULT_OUT_Y_L_ADDR+1),
+	ST_SENSORS_LSM_CHANNELS(IIO_ACCEL,
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+			ST_SENSORS_SCAN_Z, 1, IIO_MOD_Z, 's', IIO_LE, 8, 8,
+			ST_ACCEL_DEFAULT_OUT_Z_L_ADDR+1),
+	IIO_CHAN_SOFT_TIMESTAMP(3)
+};
+
 static const struct iio_chan_spec st_accel_12bit_channels[] = {
 	ST_SENSORS_LSM_CHANNELS(IIO_ACCEL,
 			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
@@ -454,6 +492,54 @@ static const struct st_sensor_settings st_accel_sensors_settings[] = {
 		.multi_read_bit = ST_ACCEL_4_MULTIREAD_BIT,
 		.bootime = 2, /* guess */
 	},
+	{
+		.wai = ST_ACCEL_5_WAI_EXP,
+		.sensors_supported = {
+			[0] = LIS331DL_ACCEL_DEV_NAME,
+		},
+		.ch = (struct iio_chan_spec *)st_accel_8bit_channels,
+		.odr = {
+			.addr = ST_ACCEL_5_ODR_ADDR,
+			.mask = ST_ACCEL_5_ODR_MASK,
+			.odr_avl = {
+				{ 100, ST_ACCEL_5_ODR_AVL_100HZ_VAL },
+				{ 400, ST_ACCEL_5_ODR_AVL_400HZ_VAL, },
+			},
+		},
+		.pw = {
+			.addr = ST_ACCEL_5_PW_ADDR,
+			.mask = ST_ACCEL_5_PW_MASK,
+			.value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
+			.value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
+		},
+		.enable_axis = {
+			.addr = ST_SENSORS_DEFAULT_AXIS_ADDR,
+			.mask = ST_SENSORS_DEFAULT_AXIS_MASK,
+		},
+		.fs = {
+			.addr = ST_ACCEL_5_FS_ADDR,
+			.mask = ST_ACCEL_5_FS_MASK,
+			.fs_avl = {
+				[0] = {
+					.num = ST_ACCEL_FS_AVL_2G,
+					.value = ST_ACCEL_5_FS_AVL_2_VAL,
+					.gain = ST_ACCEL_5_FS_AVL_2_GAIN,
+				},
+				[1] = {
+					.num = ST_ACCEL_FS_AVL_8G,
+					.value = ST_ACCEL_5_FS_AVL_8_VAL,
+					.gain = ST_ACCEL_5_FS_AVL_8_GAIN,
+				},
+			},
+		},
+		.drdy_irq = {
+			.addr = ST_ACCEL_5_DRDY_IRQ_ADDR,
+			.mask_int1 = ST_ACCEL_5_DRDY_IRQ_INT1_MASK,
+			.mask_int2 = ST_ACCEL_5_DRDY_IRQ_INT2_MASK,
+		},
+		.multi_read_bit = ST_ACCEL_5_MULTIREAD_BIT,
+		.bootime = 2, /* guess */
+	},
 };
 
 static int st_accel_read_raw(struct iio_dev *indio_dev,
diff --git a/drivers/iio/accel/st_accel_i2c.c b/drivers/iio/accel/st_accel_i2c.c
index 6b720c190b2d..d4ad72ca4a3d 100644
--- a/drivers/iio/accel/st_accel_i2c.c
+++ b/drivers/iio/accel/st_accel_i2c.c
@@ -49,6 +49,10 @@ static const struct of_device_id st_accel_of_match[] = {
 		.data = LSM330DLC_ACCEL_DEV_NAME,
 	},
 	{
+		.compatible = "st,lis331dl-accel",
+		.data = LIS331DL_ACCEL_DEV_NAME,
+	},
+	{
 		.compatible = "st,lis331dlh-accel",
 		.data = LIS331DLH_ACCEL_DEV_NAME,
 	},
diff --git a/drivers/iio/accel/stk8312.c b/drivers/iio/accel/stk8312.c
new file mode 100644
index 000000000000..d211d9f3975b
--- /dev/null
+++ b/drivers/iio/accel/stk8312.c
@@ -0,0 +1,390 @@
+/**
+ * Sensortek STK8312 3-Axis Accelerometer
+ *
+ * Copyright (c) 2015, 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 STK8312; 7-bit I2C address: 0x3D.
+ */
+
+#include <linux/acpi.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define STK8312_REG_XOUT		0x00
+#define STK8312_REG_YOUT		0x01
+#define STK8312_REG_ZOUT		0x02
+#define STK8312_REG_MODE		0x07
+#define STK8312_REG_STH			0x13
+#define STK8312_REG_RESET		0x20
+#define STK8312_REG_AFECTRL		0x24
+#define STK8312_REG_OTPADDR		0x3D
+#define STK8312_REG_OTPDATA		0x3E
+#define STK8312_REG_OTPCTRL		0x3F
+
+#define STK8312_MODE_ACTIVE		1
+#define STK8312_MODE_STANDBY		0
+#define STK8312_MODE_MASK		0x01
+#define STK8312_RNG_MASK		0xC0
+#define STK8312_RNG_SHIFT		6
+#define STK8312_READ_RETRIES		16
+
+#define STK8312_DRIVER_NAME		"stk8312"
+
+/*
+ * The accelerometer has two measurement ranges:
+ *
+ * -6g - +6g (8-bit, signed)
+ * -16g - +16g (8-bit, signed)
+ *
+ * scale1 = (6 + 6) * 9.81 / (2^8 - 1)     = 0.4616
+ * scale2 = (16 + 16) * 9.81 / (2^8 - 1)   = 1.2311
+ */
+#define STK8312_SCALE_AVAIL		"0.4616 1.2311"
+
+static const int stk8312_scale_table[][2] = {
+	{0, 461600}, {1, 231100}
+};
+
+#define STK8312_ACCEL_CHANNEL(reg, axis) {			\
+	.type = IIO_ACCEL,					\
+	.address = reg,						\
+	.modified = 1,						\
+	.channel2 = IIO_MOD_##axis,				\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+}
+
+static const struct iio_chan_spec stk8312_channels[] = {
+	STK8312_ACCEL_CHANNEL(STK8312_REG_XOUT, X),
+	STK8312_ACCEL_CHANNEL(STK8312_REG_YOUT, Y),
+	STK8312_ACCEL_CHANNEL(STK8312_REG_ZOUT, Z),
+};
+
+struct stk8312_data {
+	struct i2c_client *client;
+	struct mutex lock;
+	int range;
+	u8 mode;
+};
+
+static IIO_CONST_ATTR(in_accel_scale_available, STK8312_SCALE_AVAIL);
+
+static struct attribute *stk8312_attributes[] = {
+	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group stk8312_attribute_group = {
+	.attrs = stk8312_attributes
+};
+
+static int stk8312_otp_init(struct stk8312_data *data)
+{
+	int ret;
+	int count = 10;
+	struct i2c_client *client = data->client;
+
+	ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPADDR, 0x70);
+	if (ret < 0)
+		goto exit_err;
+	ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPCTRL, 0x02);
+	if (ret < 0)
+		goto exit_err;
+
+	do {
+		usleep_range(1000, 5000);
+		ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPCTRL);
+		if (ret < 0)
+			goto exit_err;
+		count--;
+	} while (!(ret & 0x80) && count > 0);
+
+	if (count == 0)
+		goto exit_err;
+
+	ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPDATA);
+	if (ret < 0)
+		goto exit_err;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+			STK8312_REG_AFECTRL, ret);
+	if (ret < 0)
+		goto exit_err;
+	msleep(150);
+
+	return ret;
+
+exit_err:
+	dev_err(&client->dev, "failed to initialize sensor\n");
+	return ret;
+}
+
+static int stk8312_set_mode(struct stk8312_data *data, u8 mode)
+{
+	int ret;
+	u8 masked_reg;
+	struct i2c_client *client = data->client;
+
+	if (mode > 1)
+		return -EINVAL;
+	else if (mode == data->mode)
+		return 0;
+
+	ret = i2c_smbus_read_byte_data(client, STK8312_REG_MODE);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to change sensor mode\n");
+		return ret;
+	}
+	masked_reg = ret & (~STK8312_MODE_MASK);
+	masked_reg |= mode;
+
+	ret = i2c_smbus_write_byte_data(client,
+			STK8312_REG_MODE, masked_reg);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to change sensor mode\n");
+		return ret;
+	}
+
+	data->mode = mode;
+	if (mode == STK8312_MODE_ACTIVE) {
+		/* Need to run OTP sequence before entering active mode */
+		usleep_range(1000, 5000);
+		ret = stk8312_otp_init(data);
+	}
+
+	return ret;
+}
+
+static int stk8312_set_range(struct stk8312_data *data, u8 range)
+{
+	int ret;
+	u8 masked_reg;
+	u8 mode;
+	struct i2c_client *client = data->client;
+
+	if (range != 1 && range != 2)
+		return -EINVAL;
+	else if (range == data->range)
+		return 0;
+
+	mode = data->mode;
+	/* We need to go in standby mode to modify registers */
+	ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_smbus_read_byte_data(client, STK8312_REG_STH);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to change sensor range\n");
+		return ret;
+	}
+
+	masked_reg = ret & (~STK8312_RNG_MASK);
+	masked_reg |= range << STK8312_RNG_SHIFT;
+
+	ret = i2c_smbus_write_byte_data(client, STK8312_REG_STH, masked_reg);
+	if (ret < 0)
+		dev_err(&client->dev, "failed to change sensor range\n");
+	else
+		data->range = range;
+
+	return stk8312_set_mode(data, mode);
+}
+
+static int stk8312_read_accel(struct stk8312_data *data, u8 address)
+{
+	int ret;
+	struct i2c_client *client = data->client;
+
+	if (address > 2)
+		return -EINVAL;
+
+	ret = i2c_smbus_read_byte_data(client, address);
+	if (ret < 0) {
+		dev_err(&client->dev, "register read failed\n");
+		return ret;
+	}
+
+	return sign_extend32(ret, 7);
+}
+
+static int stk8312_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct stk8312_data *data = iio_priv(indio_dev);
+
+	if (chan->type != IIO_ACCEL)
+		return -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&data->lock);
+		*val = stk8312_read_accel(data, chan->address);
+		mutex_unlock(&data->lock);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = stk8312_scale_table[data->range - 1][0];
+		*val2 = stk8312_scale_table[data->range - 1][1];
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+
+	return -EINVAL;
+}
+
+static int stk8312_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	int i;
+	int index = -1;
+	int ret;
+	struct stk8312_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		for (i = 0; i < ARRAY_SIZE(stk8312_scale_table); i++)
+			if (val == stk8312_scale_table[i][0] &&
+			    val2 == stk8312_scale_table[i][1]) {
+				index = i + 1;
+				break;
+			}
+		if (index < 0)
+			return -EINVAL;
+
+		mutex_lock(&data->lock);
+		ret = stk8312_set_range(data, index);
+		mutex_unlock(&data->lock);
+
+		return ret;
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info stk8312_info = {
+	.driver_module		= THIS_MODULE,
+	.read_raw		= stk8312_read_raw,
+	.write_raw		= stk8312_write_raw,
+	.attrs			= &stk8312_attribute_group,
+};
+
+static int stk8312_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	int ret;
+	struct iio_dev *indio_dev;
+	struct stk8312_data *data;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev) {
+		dev_err(&client->dev, "iio allocation failed!\n");
+		return -ENOMEM;
+	}
+
+	data = iio_priv(indio_dev);
+	data->client = client;
+	i2c_set_clientdata(client, indio_dev);
+	mutex_init(&data->lock);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &stk8312_info;
+	indio_dev->name = STK8312_DRIVER_NAME;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = stk8312_channels;
+	indio_dev->num_channels = ARRAY_SIZE(stk8312_channels);
+
+	/* A software reset is recommended at power-on */
+	ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_RESET, 0x00);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to reset sensor\n");
+		return ret;
+	}
+	ret = stk8312_set_range(data, 1);
+	if (ret < 0)
+		return ret;
+
+	ret = stk8312_set_mode(data, STK8312_MODE_ACTIVE);
+	if (ret < 0)
+		return ret;
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&client->dev, "device_register failed\n");
+		stk8312_set_mode(data, STK8312_MODE_STANDBY);
+	}
+
+	return ret;
+}
+
+static int stk8312_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+
+	return stk8312_set_mode(iio_priv(indio_dev), STK8312_MODE_STANDBY);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int stk8312_suspend(struct device *dev)
+{
+	struct stk8312_data *data;
+
+	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+	return stk8312_set_mode(data, STK8312_MODE_STANDBY);
+}
+
+static int stk8312_resume(struct device *dev)
+{
+	struct stk8312_data *data;
+
+	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+	return stk8312_set_mode(data, STK8312_MODE_ACTIVE);
+}
+
+static SIMPLE_DEV_PM_OPS(stk8312_pm_ops, stk8312_suspend, stk8312_resume);
+
+#define STK8312_PM_OPS (&stk8312_pm_ops)
+#else
+#define STK8312_PM_OPS NULL
+#endif
+
+static const struct i2c_device_id stk8312_i2c_id[] = {
+	{"STK8312", 0},
+	{}
+};
+
+static const struct acpi_device_id stk8312_acpi_id[] = {
+	{"STK8312", 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(acpi, stk8312_acpi_id);
+
+static struct i2c_driver stk8312_driver = {
+	.driver = {
+		.name = "stk8312",
+		.pm = STK8312_PM_OPS,
+		.acpi_match_table = ACPI_PTR(stk8312_acpi_id),
+	},
+	.probe =            stk8312_probe,
+	.remove =           stk8312_remove,
+	.id_table =         stk8312_i2c_id,
+};
+
+module_i2c_driver(stk8312_driver);
+
+MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
+MODULE_DESCRIPTION("STK8312 3-Axis Accelerometer driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/accel/stk8ba50.c b/drivers/iio/accel/stk8ba50.c
new file mode 100644
index 000000000000..30950c6b36de
--- /dev/null
+++ b/drivers/iio/accel/stk8ba50.c
@@ -0,0 +1,302 @@
+/**
+ * Sensortek STK8BA50 3-Axis Accelerometer
+ *
+ * Copyright (c) 2015, 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.
+ *
+ * STK8BA50 7-bit I2C address: 0x18.
+ */
+
+#include <linux/acpi.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define STK8BA50_REG_XOUT			0x02
+#define STK8BA50_REG_YOUT			0x04
+#define STK8BA50_REG_ZOUT			0x06
+#define STK8BA50_REG_RANGE			0x0F
+#define STK8BA50_REG_POWMODE			0x11
+#define STK8BA50_REG_SWRST			0x14
+
+#define STK8BA50_MODE_NORMAL			0
+#define STK8BA50_MODE_SUSPEND			1
+#define STK8BA50_MODE_POWERBIT			BIT(7)
+#define STK8BA50_DATA_SHIFT			6
+#define STK8BA50_RESET_CMD			0xB6
+
+#define STK8BA50_DRIVER_NAME			"stk8ba50"
+
+#define STK8BA50_SCALE_AVAIL			"0.0384 0.0767 0.1534 0.3069"
+
+/*
+ * The accelerometer has four measurement ranges:
+ * +/-2g; +/-4g; +/-8g; +/-16g
+ *
+ * Acceleration values are 10-bit, 2's complement.
+ * Scales are calculated as following:
+ *
+ * scale1 = (2 + 2) * 9.81 / (2^10 - 1)   = 0.0384
+ * scale2 = (4 + 4) * 9.81 / (2^10 - 1)   = 0.0767
+ * etc.
+ *
+ * Scales are stored in this format:
+ * { <register value>, <scale value> }
+ *
+ * Locally, the range is stored as a table index.
+ */
+static const int stk8ba50_scale_table[][2] = {
+	{3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
+};
+
+struct stk8ba50_data {
+	struct i2c_client *client;
+	struct mutex lock;
+	int range;
+};
+
+#define STK8BA50_ACCEL_CHANNEL(reg, axis) {			\
+	.type = IIO_ACCEL,					\
+	.address = reg,						\
+	.modified = 1,						\
+	.channel2 = IIO_MOD_##axis,				\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+}
+
+static const struct iio_chan_spec stk8ba50_channels[] = {
+	STK8BA50_ACCEL_CHANNEL(STK8BA50_REG_XOUT, X),
+	STK8BA50_ACCEL_CHANNEL(STK8BA50_REG_YOUT, Y),
+	STK8BA50_ACCEL_CHANNEL(STK8BA50_REG_ZOUT, Z),
+};
+
+static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
+
+static struct attribute *stk8ba50_attributes[] = {
+	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group stk8ba50_attribute_group = {
+	.attrs = stk8ba50_attributes
+};
+
+static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
+{
+	int ret;
+	struct i2c_client *client = data->client;
+
+	ret = i2c_smbus_read_word_data(client, reg);
+	if (ret < 0) {
+		dev_err(&client->dev, "register read failed\n");
+		return ret;
+	}
+
+	return sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
+}
+
+static int stk8ba50_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
+{
+	struct stk8ba50_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&data->lock);
+		*val = stk8ba50_read_accel(data, chan->address);
+		mutex_unlock(&data->lock);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		*val2 = stk8ba50_scale_table[data->range][1];
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+
+	return -EINVAL;
+}
+
+static int stk8ba50_write_raw(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan,
+			      int val, int val2, long mask)
+{
+	int ret;
+	int i;
+	int index = -1;
+	struct stk8ba50_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		if (val != 0)
+			return -EINVAL;
+
+		for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
+			if (val2 == stk8ba50_scale_table[i][1]) {
+				index = i;
+				break;
+			}
+		if (index < 0)
+			return -EINVAL;
+
+		ret = i2c_smbus_write_byte_data(data->client,
+				STK8BA50_REG_RANGE,
+				stk8ba50_scale_table[index][0]);
+		if (ret < 0)
+			dev_err(&data->client->dev,
+					"failed to set measurement range\n");
+		else
+			data->range = index;
+
+		return ret;
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info stk8ba50_info = {
+	.driver_module		= THIS_MODULE,
+	.read_raw		= stk8ba50_read_raw,
+	.write_raw		= stk8ba50_write_raw,
+	.attrs			= &stk8ba50_attribute_group,
+};
+
+static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
+{
+	int ret;
+	u8 masked_reg;
+	struct i2c_client *client = data->client;
+
+	ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
+	if (ret < 0)
+		goto exit_err;
+
+	if (mode)
+		masked_reg = ret | STK8BA50_MODE_POWERBIT;
+	else
+		masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
+
+	ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
+					masked_reg);
+	if (ret < 0)
+		goto exit_err;
+
+	return ret;
+
+exit_err:
+	dev_err(&client->dev, "failed to change sensor mode\n");
+	return ret;
+}
+
+static int stk8ba50_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	int ret;
+	struct iio_dev *indio_dev;
+	struct stk8ba50_data *data;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev) {
+		dev_err(&client->dev, "iio allocation failed!\n");
+		return -ENOMEM;
+	}
+
+	data = iio_priv(indio_dev);
+	data->client = client;
+	i2c_set_clientdata(client, indio_dev);
+	mutex_init(&data->lock);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &stk8ba50_info;
+	indio_dev->name = STK8BA50_DRIVER_NAME;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = stk8ba50_channels;
+	indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);
+
+	/* Reset all registers on startup */
+	ret = i2c_smbus_write_byte_data(client,
+			STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to reset sensor\n");
+		return ret;
+	}
+
+	/* The default range is +/-2g */
+	data->range = 0;
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&client->dev, "device_register failed\n");
+		stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
+	}
+
+	return ret;
+}
+
+static int stk8ba50_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+
+	return stk8ba50_set_power(iio_priv(indio_dev), STK8BA50_MODE_SUSPEND);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int stk8ba50_suspend(struct device *dev)
+{
+	struct stk8ba50_data *data;
+
+	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+	return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
+}
+
+static int stk8ba50_resume(struct device *dev)
+{
+	struct stk8ba50_data *data;
+
+	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+	return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
+}
+
+static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend, stk8ba50_resume);
+
+#define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
+#else
+#define STK8BA50_PM_OPS NULL
+#endif
+
+static const struct i2c_device_id stk8ba50_i2c_id[] = {
+	{"stk8ba50", 0},
+	{}
+};
+
+static const struct acpi_device_id stk8ba50_acpi_id[] = {
+	{"STK8BA50", 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);
+
+static struct i2c_driver stk8ba50_driver = {
+	.driver = {
+		.name = "stk8ba50",
+		.pm = STK8BA50_PM_OPS,
+		.acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
+	},
+	.probe =            stk8ba50_probe,
+	.remove =           stk8ba50_remove,
+	.id_table =         stk8ba50_i2c_id,
+};
+
+module_i2c_driver(stk8ba50_driver);
+
+MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
+MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
+MODULE_LICENSE("GPL v2");