Merge tag 'iio-for-3.20a_take2' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-testing

Jonathan writes:

First round of IIO new drivers, cleanups and functionality for the 3.20 cycle take 2

Updated pull request with Daniel's fix on top for the power management
Kconfig changes that had snuck in since last update of the IIO tree
worked it's way through from mainline.

Original pull message

New device support
* jsa1212 proxmity / ambient light sensor
* SM08500 supported added to the kxcjk-1013 accelerometer driver
* KMX61 Accelerometer/Magnetometer.  This took a somewhat rocky path
  being first merged, then reverted for a rewrite after a discussion of
  how to support additional functionality and finally being merged prior
  to some last reviews coming in, with resultant follow up patches.
* Freescale mma9551l driver (minor follow up warning supression patch).
* Semtech SX9500 proximity device driver.
* ak8975 gains support for ak09911 and ak09912 and drop the standalone driver
  for the ak09911.

New functionality
 * Dummy driver gains some virtual registers making it more flexible.
 * IIO_ACTIVITY channel types, with modifiers running, walking etc.  This is
   to support on chip motion clasifiers.  As such it is in the form of a
   confidence percentage.  The only devices so far only do binary decisions
   but this gives us room when other devices give more nuanced clasification.
 * IIO_EV_DIR_NONE type for events where there is no obvious direction.
   First case is step detection.
 * IIO_STEPS channel type for pedometers.
 * ENABLE mask element used to control turning on counting types such as
   the pedometer that need a 'start point'.
 * INSTANCE event type to support things that happen once.
 * info element for height calibration (used in various motion estimation
   algorithms). Note heigh tof use
 * dummy driver demonstration of the use of all the new bits above.
 * event monitor support for the new events.
 * inv_mpu6050 gains an i2c mux to allow bypassing the device to access
   additional devices connected on the other side of it.  Note that in
   Windows these are handled by firmware on the device and not exposed
   directly.
 * inv_mpu6050 gains ACPI enumeration.
 * inkern interface gains iio_write_channel_raw to allow in kernel users
   of DAC functionality via a simple wrapper.
 * Document input current readings in the ABI docs.
 * Add an error message when we get an out of range error in device tree
   processing for the in kernel interfaces.  Basically a device tree debugging
   aid.
 * Add a sanity check that a scan index for a channel is unique during
   registration.  There to help catch bugs as this should never happen
   in a bug free driver.

Cleanups and fixlets

 A rework of buffer registration from Lars - a precursor to some other
 upcoming new stuff (a few patches from others rolled in here as well).
 * Ensure all drivers register the same channels for the device and buffer.
 * Move buffer registration into the core rather than using the old
   two step approach.  Now we have simple ways of using a unified set channels
   for both without requiring channels be exposed by both interface, this
   removes a fair bit of boilerplate.
 * Stop sca3000 and ad5933 (both in staging) enabling buffer channels by
   default. It has long be convention in IIO to startup with no channels
   enabled and leave it up to userspace to say what goes in the buffer.
   Getting rid of these allows us to drop export of iio_scan_mask_set.
 * Drop get_bytes_per_datum from iio_buffer_access_funcs as not been used
   for a while.
 * Allocate standard buffer attributes in the core rather than in every
   driver with a buffer.
 * Make the length attribute read only when a driver is not able to set
   the length.
 * Drop the get_length callback for buffers as it is already available in
   struct iio_buffer.
 * Drop an unused arguement form iio_kfifo_allocate and add devm allocator
   for it.
 * some kconfig entries gain anotation with the resulting module name.
 * Fix a resulting compile issue in dummy driver due to a stub taking
   wrong parameters as a result of the above rework.
 * Fix an off by 2 error in copying the core assigned buffer attributes.

Other cleanups,
 * Trivial space before comma fixups.
 * ak8975 fixlets - none critical.  Rework to allow more device support.
 * Drop unnecessary sizeof(u8) calls.
 * bmp280 - refactor the compensation code to reduce copy operations and
   code length.  A second patch futher optimized this and performed some
   other minor cleanups.
 * kxcjk-1013 - various power control cleanups to avoid unnecessary enable
   / disable of device.  Make sure it is only controlled at all if CONFIG_PM
   is enabled.  Also som cleanups of error paths.
 * Small cleanups in adf4530 driver - pointless message and unnecessary braces.
 * Clarifiy the proximity ABI docs to make it clear it should get bigger
   as we move futher away.
 * Drop a misleading comment form industrialio-core.c
 * Trivial white space cleanups.
 * sca3000 looses an unused debug function.
 * Fix char unsigned ordering in ad8366
 * Increase the sleep time in ad9523 to make it predictable (value didn't
   really matter so make it more than 20 msecs)
 * mxs-lradc touchscreen property cleanups in device tree are fixed to ensure
   the meet all the 'interesting' documentation.
 * A couple of cleanups for the staging ad5933 driver to avoid unnecessary
   conversion to a processed temperature vlaue in kernel and remove
   platform data form the state structure as not needed after probe.
 * Fix a wrong scale factor in the docs.

Misc
 * Add IIO include files to the maintainers entry.

5 files changed, 1013 insertions, 14 deletions

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 9b9be8725e9d..9f67c10291bd 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -43,6 +43,9 @@ config HID_SENSOR_ACCEL_3D
 	  Say yes here to build support for the HID SENSOR
 	  accelerometers 3D.
 
+	  To compile this driver as a module, choose M here: the
+	  module will be called hid-sensor-accel-3d.
+
 config IIO_ST_ACCEL_3AXIS
 	tristate "STMicroelectronics accelerometers 3-Axis Driver"
 	depends on (I2C || SPI_MASTER) && SYSFS
@@ -80,6 +83,9 @@ config KXSD9
 	  Say yes here to build support for the Kionix KXSD9 accelerometer.
 	  Currently this only supports the device via an SPI interface.
 
+	  To compile this driver as a module, choose M here: the module
+	  will be called kxsd9.
+
 config MMA8452
 	tristate "Freescale MMA8452Q Accelerometer Driver"
 	depends on I2C
@@ -105,4 +111,14 @@ config KXCJK1013
 	  To compile this driver as a module, choose M here: the module will
 	  be called kxcjk-1013.
 
+config MMA9551
+	tristate "Freescale MMA9551L Intelligent Motion-Sensing Platform Driver"
+	depends on I2C
+	help
+	  Say yes here to build support for the Freescale MMA9551L
+	  Intelligent Motion-Sensing Platform Driver.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called mma9551.
+
 endmenu
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index a593996c6539..de5b9cb9670f 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
 obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
 obj-$(CONFIG_KXSD9)	+= kxsd9.o
 obj-$(CONFIG_MMA8452)	+= mma8452.o
+obj-$(CONFIG_MMA9551)	+= mma9551.o
 
 obj-$(CONFIG_IIO_ST_ACCEL_3AXIS) += st_accel.o
 st_accel-y := st_accel_core.o
diff --git a/drivers/iio/accel/kxcjk-1013.c b/drivers/iio/accel/kxcjk-1013.c
index da2fe93739a2..567de269cc00 100644
--- a/drivers/iio/accel/kxcjk-1013.c
+++ b/drivers/iio/accel/kxcjk-1013.c
@@ -108,6 +108,7 @@ struct kxcjk1013_data {
 	bool motion_trigger_on;
 	int64_t timestamp;
 	enum kx_chipset chipset;
+	bool is_smo8500_device;
 };
 
 enum kxcjk1013_axis {
@@ -377,6 +378,7 @@ static int kxcjk1013_get_startup_times(struct kxcjk1013_data *data)
 
 static int kxcjk1013_set_power_state(struct kxcjk1013_data *data, bool on)
 {
+#ifdef CONFIG_PM
 	int ret;
 
 	if (on)
@@ -388,8 +390,11 @@ static int kxcjk1013_set_power_state(struct kxcjk1013_data *data, bool on)
 	if (ret < 0) {
 		dev_err(&data->client->dev,
 			"Failed: kxcjk1013_set_power_state for %d\n", on);
+		if (on)
+			pm_runtime_put_noidle(&data->client->dev);
 		return ret;
 	}
+#endif
 
 	return 0;
 }
@@ -858,6 +863,8 @@ static int kxcjk1013_write_event_config(struct iio_dev *indio_dev,
 
 	ret =  kxcjk1013_setup_any_motion_interrupt(data, state);
 	if (ret < 0) {
+		kxcjk1013_set_power_state(data, false);
+		data->ev_enable_state = 0;
 		mutex_unlock(&data->mutex);
 		return ret;
 	}
@@ -1008,6 +1015,7 @@ static int kxcjk1013_data_rdy_trigger_set_state(struct iio_trigger *trig,
 	else
 		ret = kxcjk1013_setup_new_data_interrupt(data, state);
 	if (ret < 0) {
+		kxcjk1013_set_power_state(data, false);
 		mutex_unlock(&data->mutex);
 		return ret;
 	}
@@ -1131,12 +1139,16 @@ static irqreturn_t kxcjk1013_data_rdy_trig_poll(int irq, void *private)
 }
 
 static const char *kxcjk1013_match_acpi_device(struct device *dev,
-					       enum kx_chipset *chipset)
+					       enum kx_chipset *chipset,
+					       bool *is_smo8500_device)
 {
 	const struct acpi_device_id *id;
+
 	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);
@@ -1151,6 +1163,8 @@ static int kxcjk1013_gpio_probe(struct i2c_client *client,
 
 	if (!client)
 		return -EINVAL;
+	if (data->is_smo8500_device)
+		return -ENOTSUPP;
 
 	dev = &client->dev;
 
@@ -1200,7 +1214,8 @@ static int kxcjk1013_probe(struct i2c_client *client,
 		name = id->name;
 	} else if (ACPI_HANDLE(&client->dev)) {
 		name = kxcjk1013_match_acpi_device(&client->dev,
-						   &data->chipset);
+						   &data->chipset,
+						   &data->is_smo8500_device);
 	} else
 		return -ENODEV;
 
@@ -1228,21 +1243,25 @@ static int kxcjk1013_probe(struct i2c_client *client,
 						KXCJK1013_IRQ_NAME,
 						indio_dev);
 		if (ret)
-			return ret;
+			goto err_poweroff;
 
 		data->dready_trig = devm_iio_trigger_alloc(&client->dev,
 							   "%s-dev%d",
 							   indio_dev->name,
 							   indio_dev->id);
-		if (!data->dready_trig)
-			return -ENOMEM;
+		if (!data->dready_trig) {
+			ret = -ENOMEM;
+			goto err_poweroff;
+		}
 
 		data->motion_trig = devm_iio_trigger_alloc(&client->dev,
 							  "%s-any-motion-dev%d",
 							  indio_dev->name,
 							  indio_dev->id);
-		if (!data->motion_trig)
-			return -ENOMEM;
+		if (!data->motion_trig) {
+			ret = -ENOMEM;
+			goto err_poweroff;
+		}
 
 		data->dready_trig->dev.parent = &client->dev;
 		data->dready_trig->ops = &kxcjk1013_trigger_ops;
@@ -1251,7 +1270,7 @@ static int kxcjk1013_probe(struct i2c_client *client,
 		iio_trigger_get(indio_dev->trig);
 		ret = iio_trigger_register(data->dready_trig);
 		if (ret)
-			return ret;
+			goto err_poweroff;
 
 		data->motion_trig->dev.parent = &client->dev;
 		data->motion_trig->ops = &kxcjk1013_trigger_ops;
@@ -1300,6 +1319,8 @@ err_trigger_unregister:
 		iio_trigger_unregister(data->dready_trig);
 	if (data->motion_trig)
 		iio_trigger_unregister(data->motion_trig);
+err_poweroff:
+	kxcjk1013_set_mode(data, STANDBY);
 
 	return ret;
 }
@@ -1349,10 +1370,7 @@ static int kxcjk1013_resume(struct device *dev)
 	int ret = 0;
 
 	mutex_lock(&data->mutex);
-	/* Check, if the suspend occured while active */
-	if (data->dready_trigger_on || data->motion_trigger_on ||
-							data->ev_enable_state)
-		ret = kxcjk1013_set_mode(data, OPERATION);
+	ret = kxcjk1013_set_mode(data, OPERATION);
 	mutex_unlock(&data->mutex);
 
 	return ret;
@@ -1364,8 +1382,14 @@ static int kxcjk1013_runtime_suspend(struct device *dev)
 {
 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 	struct kxcjk1013_data *data = iio_priv(indio_dev);
+	int ret;
 
-	return kxcjk1013_set_mode(data, STANDBY);
+	ret = kxcjk1013_set_mode(data, STANDBY);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "powering off device failed\n");
+		return -EAGAIN;
+	}
+	return 0;
 }
 
 static int kxcjk1013_runtime_resume(struct device *dev)
@@ -1399,6 +1423,7 @@ static const struct acpi_device_id kx_acpi_match[] = {
 	{"KXCJ1013", KXCJK1013},
 	{"KXCJ1008", KXCJ91008},
 	{"KXTJ1009", KXTJ21009},
+	{"SMO8500",  KXCJ91008},
 	{ },
 };
 MODULE_DEVICE_TABLE(acpi, kx_acpi_match);
@@ -1407,6 +1432,7 @@ static const struct i2c_device_id kxcjk1013_id[] = {
 	{"kxcjk1013", KXCJK1013},
 	{"kxcj91008", KXCJ91008},
 	{"kxtj21009", KXTJ21009},
+	{"SMO8500",   KXCJ91008},
 	{}
 };
 
diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
index 3c12d4966376..5b80657883bb 100644
--- a/drivers/iio/accel/mma8452.c
+++ b/drivers/iio/accel/mma8452.c
@@ -111,7 +111,7 @@ static const int mma8452_samp_freq[8][2] = {
 	{6, 250000}, {1, 560000}
 };
 
-/* 
+/*
  * Hardware has fullscale of -2G, -4G, -8G corresponding to raw value -2048
  * The userspace interface uses m/s^2 and we declare micro units
  * So scale factor is given by:
diff --git a/drivers/iio/accel/mma9551.c b/drivers/iio/accel/mma9551.c
new file mode 100644
index 000000000000..6563e267b8ae
--- /dev/null
+++ b/drivers/iio/accel/mma9551.c
@@ -0,0 +1,956 @@
+/*
+ * Freescale MMA9551L Intelligent Motion-Sensing Platform driver
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+
+#define MMA9551_DRV_NAME		"mma9551"
+#define MMA9551_IRQ_NAME		"mma9551_event"
+#define MMA9551_GPIO_NAME		"mma9551_int"
+#define MMA9551_GPIO_COUNT		4
+
+/* Applications IDs */
+#define MMA9551_APPID_VERSION		0x00
+#define MMA9551_APPID_GPIO		0x03
+#define MMA9551_APPID_AFE		0x06
+#define MMA9551_APPID_TILT		0x0B
+#define MMA9551_APPID_SLEEP_WAKE	0x12
+#define MMA9551_APPID_RESET		0x17
+#define MMA9551_APPID_NONE		0xff
+
+/* Command masks for mailbox write command */
+#define MMA9551_CMD_READ_VERSION_INFO	0x00
+#define MMA9551_CMD_READ_CONFIG		0x10
+#define MMA9551_CMD_WRITE_CONFIG	0x20
+#define MMA9551_CMD_READ_STATUS		0x30
+
+enum mma9551_gpio_pin {
+	mma9551_gpio6 = 0,
+	mma9551_gpio7,
+	mma9551_gpio8,
+	mma9551_gpio9,
+	mma9551_gpio_max = mma9551_gpio9,
+};
+
+/* Mailbox read command */
+#define MMA9551_RESPONSE_COCO		BIT(7)
+
+/* Error-Status codes returned in mailbox read command */
+#define MMA9551_MCI_ERROR_NONE			0x00
+#define MMA9551_MCI_ERROR_PARAM			0x04
+#define MMA9551_MCI_INVALID_COUNT		0x19
+#define MMA9551_MCI_ERROR_COMMAND		0x1C
+#define MMA9551_MCI_ERROR_INVALID_LENGTH	0x21
+#define MMA9551_MCI_ERROR_FIFO_BUSY		0x22
+#define MMA9551_MCI_ERROR_FIFO_ALLOCATED	0x23
+#define MMA9551_MCI_ERROR_FIFO_OVERSIZE		0x24
+
+/* GPIO Application */
+#define MMA9551_GPIO_POL_MSB		0x08
+#define MMA9551_GPIO_POL_LSB		0x09
+
+/* Sleep/Wake application */
+#define MMA9551_SLEEP_CFG		0x06
+#define MMA9551_SLEEP_CFG_SNCEN		BIT(0)
+#define MMA9551_SLEEP_CFG_SCHEN		BIT(2)
+
+/* AFE application */
+#define MMA9551_AFE_X_ACCEL_REG		0x00
+#define MMA9551_AFE_Y_ACCEL_REG		0x02
+#define MMA9551_AFE_Z_ACCEL_REG		0x04
+
+/* Tilt application (inclination in IIO terms). */
+#define MMA9551_TILT_XZ_ANG_REG		0x00
+#define MMA9551_TILT_YZ_ANG_REG		0x01
+#define MMA9551_TILT_XY_ANG_REG		0x02
+#define MMA9551_TILT_ANGFLG		BIT(7)
+#define MMA9551_TILT_QUAD_REG		0x03
+#define MMA9551_TILT_XY_QUAD_SHIFT	0
+#define MMA9551_TILT_YZ_QUAD_SHIFT	2
+#define MMA9551_TILT_XZ_QUAD_SHIFT	4
+#define MMA9551_TILT_CFG_REG		0x01
+#define MMA9551_TILT_ANG_THRESH_MASK	GENMASK(3, 0)
+
+/* Tilt events are mapped to the first three GPIO pins. */
+enum mma9551_tilt_axis {
+	mma9551_x = 0,
+	mma9551_y,
+	mma9551_z,
+};
+
+/*
+ * A response is composed of:
+ * - control registers: MB0-3
+ * - data registers: MB4-31
+ *
+ * A request is composed of:
+ * - mbox to write to (always 0)
+ * - control registers: MB1-4
+ * - data registers: MB5-31
+ */
+#define MMA9551_MAILBOX_CTRL_REGS	4
+#define MMA9551_MAX_MAILBOX_DATA_REGS	28
+#define MMA9551_MAILBOX_REGS		32
+
+#define MMA9551_I2C_READ_RETRIES	5
+#define MMA9551_I2C_READ_DELAY	50	/* us */
+
+struct mma9551_mbox_request {
+	u8 start_mbox;		/* Always 0. */
+	u8 app_id;
+	/*
+	 * See Section 5.3.1 of the MMA955xL Software Reference Manual.
+	 *
+	 * Bit 7: reserved, always 0
+	 * Bits 6-4: command
+	 * Bits 3-0: upper bits of register offset
+	 */
+	u8 cmd_off;
+	u8 lower_off;
+	u8 nbytes;
+	u8 buf[MMA9551_MAX_MAILBOX_DATA_REGS - 1];
+} __packed;
+
+struct mma9551_mbox_response {
+	u8 app_id;
+	/*
+	 * See Section 5.3.3 of the MMA955xL Software Reference Manual.
+	 *
+	 * Bit 7: COCO
+	 * Bits 6-0: Error code.
+	 */
+	u8 coco_err;
+	u8 nbytes;
+	u8 req_bytes;
+	u8 buf[MMA9551_MAX_MAILBOX_DATA_REGS];
+} __packed;
+
+struct mma9551_version_info {
+	__be32 device_id;
+	u8 rom_version[2];
+	u8 fw_version[2];
+	u8 hw_version[2];
+	u8 fw_build[2];
+};
+
+struct mma9551_data {
+	struct i2c_client *client;
+	struct mutex mutex;
+	int event_enabled[3];
+	int irqs[MMA9551_GPIO_COUNT];
+};
+
+static int mma9551_transfer(struct i2c_client *client,
+			    u8 app_id, u8 command, u16 offset,
+			    u8 *inbytes, int num_inbytes,
+			    u8 *outbytes, int num_outbytes)
+{
+	struct mma9551_mbox_request req;
+	struct mma9551_mbox_response rsp;
+	struct i2c_msg in, out;
+	u8 req_len, err_code;
+	int ret, retries;
+
+	if (offset >= 1 << 12) {
+		dev_err(&client->dev, "register offset too large\n");
+		return -EINVAL;
+	}
+
+	req_len = 1 + MMA9551_MAILBOX_CTRL_REGS + num_inbytes;
+	req.start_mbox = 0;
+	req.app_id = app_id;
+	req.cmd_off = command | (offset >> 8);
+	req.lower_off = offset;
+
+	if (command == MMA9551_CMD_WRITE_CONFIG)
+		req.nbytes = num_inbytes;
+	else
+		req.nbytes = num_outbytes;
+	if (num_inbytes)
+		memcpy(req.buf, inbytes, num_inbytes);
+
+	out.addr = client->addr;
+	out.flags = 0;
+	out.len = req_len;
+	out.buf = (u8 *)&req;
+
+	ret = i2c_transfer(client->adapter, &out, 1);
+	if (ret < 0) {
+		dev_err(&client->dev, "i2c write failed\n");
+		return ret;
+	}
+
+	retries = MMA9551_I2C_READ_RETRIES;
+	do {
+		udelay(MMA9551_I2C_READ_DELAY);
+
+		in.addr = client->addr;
+		in.flags = I2C_M_RD;
+		in.len = sizeof(rsp);
+		in.buf = (u8 *)&rsp;
+
+		ret = i2c_transfer(client->adapter, &in, 1);
+		if (ret < 0) {
+			dev_err(&client->dev, "i2c read failed\n");
+			return ret;
+		}
+
+		if (rsp.coco_err & MMA9551_RESPONSE_COCO)
+			break;
+	} while (--retries > 0);
+
+	if (retries == 0) {
+		dev_err(&client->dev,
+			"timed out while waiting for command response\n");
+		return -ETIMEDOUT;
+	}
+
+	if (rsp.app_id != app_id) {
+		dev_err(&client->dev,
+			"app_id mismatch in response got %02x expected %02x\n",
+			rsp.app_id, app_id);
+		return -EINVAL;
+	}
+
+	err_code = rsp.coco_err & ~MMA9551_RESPONSE_COCO;
+	if (err_code != MMA9551_MCI_ERROR_NONE) {
+		dev_err(&client->dev, "read returned error %x\n", err_code);
+		return -EINVAL;
+	}
+
+	if (rsp.nbytes != rsp.req_bytes) {
+		dev_err(&client->dev,
+			"output length mismatch got %d expected %d\n",
+			rsp.nbytes, rsp.req_bytes);
+		return -EINVAL;
+	}
+
+	if (num_outbytes)
+		memcpy(outbytes, rsp.buf, num_outbytes);
+
+	return 0;
+}
+
+static int mma9551_read_config_byte(struct i2c_client *client, u8 app_id,
+				    u16 reg, u8 *val)
+{
+	return mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
+				reg, NULL, 0, val, 1);
+}
+
+static int mma9551_write_config_byte(struct i2c_client *client, u8 app_id,
+				     u16 reg, u8 val)
+{
+	return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG, reg,
+				&val, 1, NULL, 0);
+}
+
+static int mma9551_read_status_byte(struct i2c_client *client, u8 app_id,
+				    u16 reg, u8 *val)
+{
+	return mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
+				reg, NULL, 0, val, 1);
+}
+
+static int mma9551_read_status_word(struct i2c_client *client, u8 app_id,
+				    u16 reg, u16 *val)
+{
+	int ret;
+	__be16 v;
+
+	ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
+			       reg, NULL, 0, (u8 *)&v, 2);
+	*val = be16_to_cpu(v);
+
+	return ret;
+}
+
+static int mma9551_update_config_bits(struct i2c_client *client, u8 app_id,
+				      u16 reg, u8 mask, u8 val)
+{
+	int ret;
+	u8 tmp, orig;
+
+	ret = mma9551_read_config_byte(client, app_id, reg, &orig);
+	if (ret < 0)
+		return ret;
+
+	tmp = orig & ~mask;
+	tmp |= val & mask;
+
+	if (tmp == orig)
+		return 0;
+
+	return mma9551_write_config_byte(client, app_id, reg, tmp);
+}
+
+/*
+ * The polarity parameter is described in section 6.2.2, page 66, of the
+ * Software Reference Manual.  Basically, polarity=0 means the interrupt
+ * line has the same value as the selected bit, while polarity=1 means
+ * the line is inverted.
+ */
+static int mma9551_gpio_config(struct i2c_client *client,
+			       enum mma9551_gpio_pin pin,
+			       u8 app_id, u8 bitnum, int polarity)
+{
+	u8 reg, pol_mask, pol_val;
+	int ret;
+
+	if (pin > mma9551_gpio_max) {
+		dev_err(&client->dev, "bad GPIO pin\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Pin 6 is configured by regs 0x00 and 0x01, pin 7 by 0x02 and
+	 * 0x03, and so on.
+	 */
+	reg = pin * 2;
+
+	ret = mma9551_write_config_byte(client, MMA9551_APPID_GPIO,
+					reg, app_id);
+	if (ret < 0) {
+		dev_err(&client->dev, "error setting GPIO app_id\n");
+		return ret;
+	}
+
+	ret = mma9551_write_config_byte(client, MMA9551_APPID_GPIO,
+					reg + 1, bitnum);
+	if (ret < 0) {
+		dev_err(&client->dev, "error setting GPIO bit number\n");
+		return ret;
+	}
+
+	switch (pin) {
+	case mma9551_gpio6:
+		reg = MMA9551_GPIO_POL_LSB;
+		pol_mask = 1 << 6;
+		break;
+	case mma9551_gpio7:
+		reg = MMA9551_GPIO_POL_LSB;
+		pol_mask = 1 << 7;
+		break;
+	case mma9551_gpio8:
+		reg = MMA9551_GPIO_POL_MSB;
+		pol_mask = 1 << 0;
+		break;
+	case mma9551_gpio9:
+		reg = MMA9551_GPIO_POL_MSB;
+		pol_mask = 1 << 1;
+		break;
+	}
+	pol_val = polarity ? pol_mask : 0;
+
+	ret = mma9551_update_config_bits(client, MMA9551_APPID_GPIO, reg,
+					 pol_mask, pol_val);
+	if (ret < 0)
+		dev_err(&client->dev, "error setting GPIO polarity\n");
+
+	return ret;
+}
+
+static int mma9551_read_version(struct i2c_client *client)
+{
+	struct mma9551_version_info info;
+	int ret;
+
+	ret = mma9551_transfer(client, MMA9551_APPID_VERSION, 0x00, 0x00,
+			       NULL, 0, (u8 *)&info, sizeof(info));
+	if (ret < 0)
+		return ret;
+
+	dev_info(&client->dev, "Device ID 0x%x, firmware version %02x.%02x\n",
+		 be32_to_cpu(info.device_id), info.fw_version[0],
+		 info.fw_version[1]);
+
+	return 0;
+}
+
+/*
+ * Use 'false' as the second parameter to cause the device to enter
+ * sleep.
+ */
+static int mma9551_set_device_state(struct i2c_client *client,
+				    bool enable)
+{
+	return mma9551_update_config_bits(client, MMA9551_APPID_SLEEP_WAKE,
+					  MMA9551_SLEEP_CFG,
+					  MMA9551_SLEEP_CFG_SNCEN,
+					  enable ? 0 : MMA9551_SLEEP_CFG_SNCEN);
+}
+
+static int mma9551_read_incli_chan(struct i2c_client *client,
+				   const struct iio_chan_spec *chan,
+				   int *val)
+{
+	u8 quad_shift, angle, quadrant;
+	u16 reg_addr;
+	int ret;
+
+	switch (chan->channel2) {
+	case IIO_MOD_X:
+		reg_addr = MMA9551_TILT_YZ_ANG_REG;
+		quad_shift = MMA9551_TILT_YZ_QUAD_SHIFT;
+		break;
+	case IIO_MOD_Y:
+		reg_addr = MMA9551_TILT_XZ_ANG_REG;
+		quad_shift = MMA9551_TILT_XZ_QUAD_SHIFT;
+		break;
+	case IIO_MOD_Z:
+		reg_addr = MMA9551_TILT_XY_ANG_REG;
+		quad_shift = MMA9551_TILT_XY_QUAD_SHIFT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = mma9551_read_status_byte(client, MMA9551_APPID_TILT,
+				       reg_addr, &angle);
+	if (ret < 0)
+		return ret;
+
+	ret = mma9551_read_status_byte(client, MMA9551_APPID_TILT,
+				       MMA9551_TILT_QUAD_REG, &quadrant);
+	if (ret < 0)
+		return ret;
+
+	angle &= ~MMA9551_TILT_ANGFLG;
+	quadrant = (quadrant >> quad_shift) & 0x03;
+
+	if (quadrant == 1 || quadrant == 3)
+		*val = 90 * (quadrant + 1) - angle;
+	else
+		*val = angle + 90 * quadrant;
+
+	return IIO_VAL_INT;
+}
+
+static int mma9551_read_accel_chan(struct i2c_client *client,
+				   const struct iio_chan_spec *chan,
+				   int *val, int *val2)
+{
+	u16 reg_addr;
+	s16 raw_accel;
+	int ret;
+
+	switch (chan->channel2) {
+	case IIO_MOD_X:
+		reg_addr = MMA9551_AFE_X_ACCEL_REG;
+		break;
+	case IIO_MOD_Y:
+		reg_addr = MMA9551_AFE_Y_ACCEL_REG;
+		break;
+	case IIO_MOD_Z:
+		reg_addr = MMA9551_AFE_Z_ACCEL_REG;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = mma9551_read_status_word(client, MMA9551_APPID_AFE,
+				       reg_addr, &raw_accel);
+	if (ret < 0)
+		return ret;
+
+	*val = raw_accel;
+
+	return IIO_VAL_INT;
+}
+
+static int mma9551_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct mma9551_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_PROCESSED:
+		switch (chan->type) {
+		case IIO_INCLI:
+			mutex_lock(&data->mutex);
+			ret = mma9551_read_incli_chan(data->client, chan, val);
+			mutex_unlock(&data->mutex);
+			return ret;
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_RAW:
+		switch (chan->type) {
+		case IIO_ACCEL:
+			mutex_lock(&data->mutex);
+			ret = mma9551_read_accel_chan(data->client,
+						      chan, val, val2);
+			mutex_unlock(&data->mutex);
+			return ret;
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_ACCEL:
+			*val = 0;
+			*val2 = 2440;
+			return IIO_VAL_INT_PLUS_MICRO;
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static int mma9551_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 mma9551_data *data = iio_priv(indio_dev);
+
+	switch (chan->type) {
+	case IIO_INCLI:
+		/* IIO counts axes from 1, because IIO_NO_MOD is 0. */
+		return data->event_enabled[chan->channel2 - 1];
+	default:
+		return -EINVAL;
+	}
+}
+
+static int mma9551_config_incli_event(struct iio_dev *indio_dev,
+				      enum iio_modifier axis,
+				      int state)
+{
+	struct mma9551_data *data = iio_priv(indio_dev);
+	enum mma9551_tilt_axis mma_axis;
+	int ret;
+
+	/* IIO counts axes from 1, because IIO_NO_MOD is 0. */
+	mma_axis = axis - 1;
+
+	if (data->event_enabled[mma_axis] == state)
+		return 0;
+
+	if (state == 0) {
+		ret = mma9551_gpio_config(data->client,
+					  (enum mma9551_gpio_pin)mma_axis,
+					  MMA9551_APPID_NONE, 0, 0);
+		if (ret < 0)
+			return ret;
+	} else {
+		int bitnum;
+
+		/* Bit 7 of each angle register holds the angle flag. */
+		switch (axis) {
+		case IIO_MOD_X:
+			bitnum = 7 + 8 * MMA9551_TILT_YZ_ANG_REG;
+			break;
+		case IIO_MOD_Y:
+			bitnum = 7 + 8 * MMA9551_TILT_XZ_ANG_REG;
+			break;
+		case IIO_MOD_Z:
+			bitnum = 7 + 8 * MMA9551_TILT_XY_ANG_REG;
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		ret = mma9551_gpio_config(data->client,
+					  (enum mma9551_gpio_pin)mma_axis,
+					  MMA9551_APPID_TILT, bitnum, 0);
+		if (ret < 0)
+			return ret;
+	}
+
+	data->event_enabled[mma_axis] = state;
+
+	return ret;
+}
+
+static int mma9551_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 mma9551_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (chan->type) {
+	case IIO_INCLI:
+		mutex_lock(&data->mutex);
+		ret = mma9551_config_incli_event(indio_dev,
+						 chan->channel2, state);
+		mutex_unlock(&data->mutex);
+		return ret;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int mma9551_write_event_value(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 mma9551_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (chan->type) {
+	case IIO_INCLI:
+		if (val2 != 0 || val < 1 || val > 10)
+			return -EINVAL;
+		mutex_lock(&data->mutex);
+		ret = mma9551_update_config_bits(data->client,
+						 MMA9551_APPID_TILT,
+						 MMA9551_TILT_CFG_REG,
+						 MMA9551_TILT_ANG_THRESH_MASK,
+						 val);
+		mutex_unlock(&data->mutex);
+		return ret;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int mma9551_read_event_value(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 mma9551_data *data = iio_priv(indio_dev);
+	int ret;
+	u8 tmp;
+
+	switch (chan->type) {
+	case IIO_INCLI:
+		mutex_lock(&data->mutex);
+		ret = mma9551_read_config_byte(data->client,
+					       MMA9551_APPID_TILT,
+					       MMA9551_TILT_CFG_REG, &tmp);
+		mutex_unlock(&data->mutex);
+		if (ret < 0)
+			return ret;
+		*val = tmp & MMA9551_TILT_ANG_THRESH_MASK;
+		*val2 = 0;
+		return IIO_VAL_INT;
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_event_spec mma9551_incli_event = {
+	.type = IIO_EV_TYPE_ROC,
+	.dir = IIO_EV_DIR_RISING,
+	.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+	.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
+};
+
+#define MMA9551_ACCEL_CHANNEL(axis) {				\
+	.type = IIO_ACCEL,					\
+	.modified = 1,						\
+	.channel2 = axis,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+}
+
+#define MMA9551_INCLI_CHANNEL(axis) {				\
+	.type = IIO_INCLI,					\
+	.modified = 1,						\
+	.channel2 = axis,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),	\
+	.event_spec = &mma9551_incli_event,			\
+	.num_event_specs = 1,					\
+}
+
+static const struct iio_chan_spec mma9551_channels[] = {
+	MMA9551_ACCEL_CHANNEL(IIO_MOD_X),
+	MMA9551_ACCEL_CHANNEL(IIO_MOD_Y),
+	MMA9551_ACCEL_CHANNEL(IIO_MOD_Z),
+
+	MMA9551_INCLI_CHANNEL(IIO_MOD_X),
+	MMA9551_INCLI_CHANNEL(IIO_MOD_Y),
+	MMA9551_INCLI_CHANNEL(IIO_MOD_Z),
+};
+
+static const struct iio_info mma9551_info = {
+	.driver_module = THIS_MODULE,
+	.read_raw = mma9551_read_raw,
+	.read_event_config = mma9551_read_event_config,
+	.write_event_config = mma9551_write_event_config,
+	.read_event_value = mma9551_read_event_value,
+	.write_event_value = mma9551_write_event_value,
+};
+
+static irqreturn_t mma9551_event_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct mma9551_data *data = iio_priv(indio_dev);
+	int i, ret, mma_axis = -1;
+	u16 reg;
+	u8 val;
+
+	mutex_lock(&data->mutex);
+
+	for (i = 0; i < 3; i++)
+		if (irq == data->irqs[i]) {
+			mma_axis = i;
+			break;
+		}
+
+	if (mma_axis == -1) {
+		/* IRQ was triggered on 4th line, which we don't use. */
+		dev_warn(&data->client->dev,
+			 "irq triggered on unused line %d\n", data->irqs[3]);
+		goto out;
+	}
+
+	switch (mma_axis) {
+	case mma9551_x:
+		reg = MMA9551_TILT_YZ_ANG_REG;
+		break;
+	case mma9551_y:
+		reg = MMA9551_TILT_XZ_ANG_REG;
+		break;
+	case mma9551_z:
+		reg = MMA9551_TILT_XY_ANG_REG;
+		break;
+	}
+
+	/*
+	 * Read the angle even though we don't use it, otherwise we
+	 * won't get any further interrupts.
+	 */
+	ret = mma9551_read_status_byte(data->client, MMA9551_APPID_TILT,
+				       reg, &val);
+	if (ret < 0) {
+		dev_err(&data->client->dev,
+			"error %d reading tilt register in IRQ\n", ret);
+		goto out;
+	}
+
+	iio_push_event(indio_dev,
+		       IIO_MOD_EVENT_CODE(IIO_INCLI, 0, (mma_axis + 1),
+					  IIO_EV_TYPE_ROC, IIO_EV_DIR_RISING),
+		       iio_get_time_ns());
+
+out:
+	mutex_unlock(&data->mutex);
+
+	return IRQ_HANDLED;
+}
+
+static int mma9551_init(struct mma9551_data *data)
+{
+	int ret;
+
+	ret = mma9551_read_version(data->client);
+	if (ret)
+		return ret;
+
+	/* Power on chip and enable doze mode. */
+	return mma9551_update_config_bits(data->client,
+			 MMA9551_APPID_SLEEP_WAKE,
+			 MMA9551_SLEEP_CFG,
+			 MMA9551_SLEEP_CFG_SCHEN | MMA9551_SLEEP_CFG_SNCEN,
+			 MMA9551_SLEEP_CFG_SCHEN);
+}
+
+static int mma9551_gpio_probe(struct iio_dev *indio_dev)
+{
+	struct gpio_desc *gpio;
+	int i, ret;
+	struct mma9551_data *data = iio_priv(indio_dev);
+	struct device *dev = &data->client->dev;
+
+	for (i = 0; i < MMA9551_GPIO_COUNT; i++) {
+		gpio = devm_gpiod_get_index(dev, MMA9551_GPIO_NAME, i);
+		if (IS_ERR(gpio)) {
+			dev_err(dev, "acpi gpio get index failed\n");
+			return PTR_ERR(gpio);
+		}
+
+		ret = gpiod_direction_input(gpio);
+		if (ret)
+			return ret;
+
+		data->irqs[i] = gpiod_to_irq(gpio);
+		ret = devm_request_threaded_irq(dev, data->irqs[i],
+				NULL, mma9551_event_handler,
+				IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+				MMA9551_IRQ_NAME, indio_dev);
+		if (ret < 0) {
+			dev_err(dev, "request irq %d failed\n", data->irqs[i]);
+			return ret;
+		}
+
+		dev_dbg(dev, "gpio resource, no:%d irq:%d\n",
+			desc_to_gpio(gpio), data->irqs[i]);
+	}
+
+	return 0;
+}
+
+static const char *mma9551_match_acpi_device(struct device *dev)
+{
+	const struct acpi_device_id *id;
+
+	id = acpi_match_device(dev->driver->acpi_match_table, dev);
+	if (!id)
+		return NULL;
+
+	return dev_name(dev);
+}
+
+static int mma9551_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct mma9551_data *data;
+	struct iio_dev *indio_dev;
+	const char *name = NULL;
+	int ret;
+
+	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;
+	else if (ACPI_HANDLE(&client->dev))
+		name = mma9551_match_acpi_device(&client->dev);
+
+	ret = mma9551_init(data);
+	if (ret < 0)
+		return ret;
+
+	mutex_init(&data->mutex);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->channels = mma9551_channels;
+	indio_dev->num_channels = ARRAY_SIZE(mma9551_channels);
+	indio_dev->name = name;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &mma9551_info;
+
+	ret = mma9551_gpio_probe(indio_dev);
+	if (ret < 0)
+		goto out_poweroff;
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&client->dev, "unable to register iio device\n");
+		goto out_poweroff;
+	}
+
+	return 0;
+
+out_poweroff:
+	mma9551_set_device_state(client, false);
+
+	return ret;
+}
+
+static int mma9551_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct mma9551_data *data = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	mutex_lock(&data->mutex);
+	mma9551_set_device_state(data->client, false);
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mma9551_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct mma9551_data *data = iio_priv(indio_dev);
+
+	mutex_lock(&data->mutex);
+	mma9551_set_device_state(data->client, false);
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+
+static int mma9551_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct mma9551_data *data = iio_priv(indio_dev);
+
+	mutex_lock(&data->mutex);
+	mma9551_set_device_state(data->client, true);
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+#else
+#define mma9551_suspend NULL
+#define mma9551_resume NULL
+#endif
+
+static const struct dev_pm_ops mma9551_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(mma9551_suspend, mma9551_resume)
+};
+
+static const struct acpi_device_id mma9551_acpi_match[] = {
+	{"MMA9551", 0},
+	{},
+};
+
+MODULE_DEVICE_TABLE(acpi, mma9551_acpi_match);
+
+static const struct i2c_device_id mma9551_id[] = {
+	{"mma9551", 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, mma9551_id);
+
+static struct i2c_driver mma9551_driver = {
+	.driver = {
+		   .name = MMA9551_DRV_NAME,
+		   .acpi_match_table = ACPI_PTR(mma9551_acpi_match),
+		   .pm = &mma9551_pm_ops,
+		   },
+	.probe = mma9551_probe,
+	.remove = mma9551_remove,
+	.id_table = mma9551_id,
+};
+
+module_i2c_driver(mma9551_driver);
+
+MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
+MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MMA9551L motion-sensing platform driver");