Merge tag 'staging-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging tree update from Greg Kroah-Hartman:
 "Here is the big staging tree update for the 3.7-rc1 merge window.

  There are a few patches in here that are outside of the staging area,
  namely HID and IIO patches, but all of them have been acked by the
  relevant subsystem maintainers.  The IIO stuff is still coming in
  through this tree as it hasn't entirely moved out of the staging tree,
  but is almost there.

  Other than that, there wa a ton of work on the comedi drivers to make
  them more readable and the correct style.  Doing that removed a lot of
  code, but we added a new driver to the staging tree, so we didn't end
  up with a net reduction this time around:

   662 files changed, 51649 insertions(+), 26582 deletions(-)

  All of these patches have been in the linux-next tree already.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'staging-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1094 commits)
  staging: comedi: jr3_pci: fix iomem dereference
  staging: comedi: drivers: use comedi_fc.h cmdtest helpers
  Staging: winbond: usb_free_urb(NULL) is safe
  Staging: winbond: checkpatch cleanup
  Staging: winbond: Removed undesired spaces, lines and tabs
  Staging: winbond: Typo corrections in comments
  Staging: winbond: Changed c99 comments to c89 comments
  staging: r8712u: Do not queue cloned skb
  staging: comedi: ni_mio_common: always lock in ni_ai_poll()
  staging: comedi: s626: add FIXME comment
  staging: comedi: s626: don't dereference insn->data
  staging: comedi: s526: fix if() check in s526_gpct_winsn()
  staging: comedi: s626: cleanup comments in s626_initialize()
  staging: comedi: s626: remove clear of kzalloc'ed data
  staging: comedi: s626: remove 'WDInterval' from private data
  staging: comedi: s626: remove 'ChargeEnabled' from private data
  staging: comedi: s626: remove 'IsBoardRevA' comment
  staging: comedi: s626: #if 0 out the "SAA7146 BUG WORKAROUND"
  staging: comedi: s626: remove 'allocatedBuf' from private data
  staging: comedi: s626: add final attach message
  ...

9 files changed, 301 insertions, 20 deletions

diff --git a/include/linux/iio/adc/ad_sigma_delta.h b/include/linux/iio/adc/ad_sigma_delta.h
new file mode 100644
index 000000000000..2e4eab9868a3
--- /dev/null
+++ b/include/linux/iio/adc/ad_sigma_delta.h
@@ -0,0 +1,173 @@
+/*
+ * Support code for Analog Devices Sigma-Delta ADCs
+ *
+ * Copyright 2012 Analog Devices Inc.
+ *  Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Licensed under the GPL-2.
+ */
+#ifndef __AD_SIGMA_DELTA_H__
+#define __AD_SIGMA_DELTA_H__
+
+enum ad_sigma_delta_mode {
+	AD_SD_MODE_CONTINUOUS = 0,
+	AD_SD_MODE_SINGLE = 1,
+	AD_SD_MODE_IDLE = 2,
+	AD_SD_MODE_POWERDOWN = 3,
+};
+
+/**
+ * struct ad_sigma_delta_calib_data - Calibration data for Sigma Delta devices
+ * @mode: Calibration mode.
+ * @channel: Calibration channel.
+ */
+struct ad_sd_calib_data {
+	unsigned int mode;
+	unsigned int channel;
+};
+
+struct ad_sigma_delta;
+struct iio_dev;
+
+/**
+ * struct ad_sigma_delta_info - Sigma Delta driver specific callbacks and options
+ * @set_channel: Will be called to select the current channel, may be NULL.
+ * @set_mode: Will be called to select the current mode, may be NULL.
+ * @postprocess_sample: Is called for each sampled data word, can be used to
+ *		modify or drop the sample data, it, may be NULL.
+ * @has_registers: true if the device has writable and readable registers, false
+ *		if there is just one read-only sample data shift register.
+ * @addr_shift: Shift of the register address in the communications register.
+ * @read_mask: Mask for the communications register having the read bit set.
+ */
+struct ad_sigma_delta_info {
+	int (*set_channel)(struct ad_sigma_delta *, unsigned int channel);
+	int (*set_mode)(struct ad_sigma_delta *, enum ad_sigma_delta_mode mode);
+	int (*postprocess_sample)(struct ad_sigma_delta *, unsigned int raw_sample);
+	bool has_registers;
+	unsigned int addr_shift;
+	unsigned int read_mask;
+};
+
+/**
+ * struct ad_sigma_delta - Sigma Delta device struct
+ * @spi: The spi device associated with the Sigma Delta device.
+ * @trig: The IIO trigger associated with the Sigma Delta device.
+ *
+ * Most of the fields are private to the sigma delta library code and should not
+ * be accessed by individual drivers.
+ */
+struct ad_sigma_delta {
+	struct spi_device	*spi;
+	struct iio_trigger	*trig;
+
+/* private: */
+	struct completion	completion;
+	bool			irq_dis;
+
+	bool			bus_locked;
+
+	uint8_t			comm;
+
+	const struct ad_sigma_delta_info *info;
+
+	/*
+	 * DMA (thus cache coherency maintenance) requires the
+	 * transfer buffers to live in their own cache lines.
+	 */
+	uint8_t				data[4] ____cacheline_aligned;
+};
+
+static inline int ad_sigma_delta_set_channel(struct ad_sigma_delta *sd,
+	unsigned int channel)
+{
+	if (sd->info->set_channel)
+		return sd->info->set_channel(sd, channel);
+
+	return 0;
+}
+
+static inline int ad_sigma_delta_set_mode(struct ad_sigma_delta *sd,
+	unsigned int mode)
+{
+	if (sd->info->set_mode)
+		return sd->info->set_mode(sd, mode);
+
+	return 0;
+}
+
+static inline int ad_sigma_delta_postprocess_sample(struct ad_sigma_delta *sd,
+	unsigned int raw_sample)
+{
+	if (sd->info->postprocess_sample)
+		return sd->info->postprocess_sample(sd, raw_sample);
+
+	return 0;
+}
+
+void ad_sd_set_comm(struct ad_sigma_delta *sigma_delta, uint8_t comm);
+int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg,
+	unsigned int size, unsigned int val);
+int ad_sd_read_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg,
+	unsigned int size, unsigned int *val);
+
+int ad_sigma_delta_single_conversion(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, int *val);
+int ad_sd_calibrate_all(struct ad_sigma_delta *sigma_delta,
+	const struct ad_sd_calib_data *cd, unsigned int n);
+int ad_sd_init(struct ad_sigma_delta *sigma_delta, struct iio_dev *indio_dev,
+	struct spi_device *spi, const struct ad_sigma_delta_info *info);
+
+int ad_sd_setup_buffer_and_trigger(struct iio_dev *indio_dev);
+void ad_sd_cleanup_buffer_and_trigger(struct iio_dev *indio_dev);
+
+int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig);
+
+#define __AD_SD_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
+	_storagebits, _shift, _extend_name, _type) \
+	{ \
+		.type = (_type), \
+		.differential = (_channel2 == -1 ? 0 : 1), \
+		.indexed = 1, \
+		.channel = (_channel1), \
+		.channel2 = (_channel2), \
+		.address = (_address), \
+		.extend_name = (_extend_name), \
+		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
+			IIO_CHAN_INFO_SCALE_SHARED_BIT | \
+			IIO_CHAN_INFO_OFFSET_SEPARATE_BIT, \
+		.scan_index = (_si), \
+		.scan_type = { \
+			.sign = 'u', \
+			.realbits = (_bits), \
+			.storagebits = (_storagebits), \
+			.shift = (_shift), \
+			.endianness = IIO_BE, \
+		}, \
+	}
+
+#define AD_SD_DIFF_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
+	_storagebits, _shift) \
+	__AD_SD_CHANNEL(_si, _channel1, _channel2, _address, _bits, \
+		_storagebits, _shift, NULL, IIO_VOLTAGE)
+
+#define AD_SD_SHORTED_CHANNEL(_si, _channel, _address, _bits, \
+	_storagebits, _shift) \
+	__AD_SD_CHANNEL(_si, _channel, _channel, _address, _bits, \
+		_storagebits, _shift, "shorted", IIO_VOLTAGE)
+
+#define AD_SD_CHANNEL(_si, _channel, _address, _bits, \
+	_storagebits, _shift) \
+	__AD_SD_CHANNEL(_si, _channel, -1, _address, _bits, \
+		_storagebits, _shift, NULL, IIO_VOLTAGE)
+
+#define AD_SD_TEMP_CHANNEL(_si, _address, _bits, _storagebits, _shift) \
+	__AD_SD_CHANNEL(_si, 0, -1, _address, _bits, \
+		_storagebits, _shift, NULL, IIO_TEMP)
+
+#define AD_SD_SUPPLY_CHANNEL(_si, _channel, _address, _bits, _storagebits, \
+	_shift) \
+	__AD_SD_CHANNEL(_si, _channel, -1, _address, _bits, \
+		_storagebits, _shift, "supply", IIO_VOLTAGE)
+
+#endif
diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h
index 8ba516fc2ec6..c629b3a1d9a9 100644
--- a/include/linux/iio/buffer.h
+++ b/include/linux/iio/buffer.h
@@ -36,7 +36,7 @@ struct iio_buffer;
  * any of them not existing.
  **/
 struct iio_buffer_access_funcs {
-	int (*store_to)(struct iio_buffer *buffer, u8 *data, s64 timestamp);
+	int (*store_to)(struct iio_buffer *buffer, u8 *data);
 	int (*read_first_n)(struct iio_buffer *buffer,
 			    size_t n,
 			    char __user *buf);
@@ -118,10 +118,8 @@ int iio_scan_mask_set(struct iio_dev *indio_dev,
  * iio_push_to_buffer() - push to a registered buffer.
  * @buffer:		IIO buffer structure for device
  * @data:		the data to push to the buffer
- * @timestamp:		timestamp to associate with the data
  */
-int iio_push_to_buffer(struct iio_buffer *buffer, unsigned char *data,
-		       s64 timestamp);
+int iio_push_to_buffer(struct iio_buffer *buffer, unsigned char *data);
 
 int iio_update_demux(struct iio_dev *indio_dev);
 
diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
index e2657e6d4d26..e875bcf0478f 100644
--- a/include/linux/iio/consumer.h
+++ b/include/linux/iio/consumer.h
@@ -8,7 +8,7 @@
  * the Free Software Foundation.
  */
 #ifndef _IIO_INKERN_CONSUMER_H_
-#define _IIO_INKERN_CONSUMER_H
+#define _IIO_INKERN_CONSUMER_H_
 #include <linux/iio/types.h>
 
 struct iio_dev;
@@ -61,7 +61,7 @@ void iio_channel_release_all(struct iio_channel *chan);
 
 /**
  * iio_read_channel_raw() - read from a given channel
- * @channel:		The channel being queried.
+ * @chan:		The channel being queried.
  * @val:		Value read back.
  *
  * Note raw reads from iio channels are in adc counts and hence
@@ -71,6 +71,21 @@ int iio_read_channel_raw(struct iio_channel *chan,
 			 int *val);
 
 /**
+ * iio_read_channel_processed() - read processed value from a given channel
+ * @chan:		The channel being queried.
+ * @val:		Value read back.
+ *
+ * Returns an error code or 0.
+ *
+ * This function will read a processed value from a channel. A processed value
+ * means that this value will have the correct unit and not some device internal
+ * representation. If the device does not support reporting a processed value
+ * the function will query the raw value and the channels scale and offset and
+ * do the appropriate transformation.
+ */
+int iio_read_channel_processed(struct iio_channel *chan, int *val);
+
+/**
  * iio_get_channel_type() - get the type of a channel
  * @channel:		The channel being queried.
  * @type:		The type of the channel.
@@ -82,7 +97,7 @@ int iio_get_channel_type(struct iio_channel *channel,
 
 /**
  * iio_read_channel_scale() - read the scale value for a channel
- * @channel:		The channel being queried.
+ * @chan:		The channel being queried.
  * @val:		First part of value read back.
  * @val2:		Second part of value read back.
  *
@@ -93,4 +108,27 @@ int iio_get_channel_type(struct iio_channel *channel,
 int iio_read_channel_scale(struct iio_channel *chan, int *val,
 			   int *val2);
 
+/**
+ * iio_convert_raw_to_processed() - Converts a raw value to a processed value
+ * @chan:		The channel being queried
+ * @raw:		The raw IIO to convert
+ * @processed:		The result of the conversion
+ * @scale:		Scale factor to apply during the conversion
+ *
+ * Returns an error code or 0.
+ *
+ * This function converts a raw value to processed value for a specific channel.
+ * A raw value is the device internal representation of a sample and the value
+ * returned by iio_read_channel_raw, so the unit of that value is device
+ * depended. A processed value on the other hand is value has a normed unit
+ * according with the IIO specification.
+ *
+ * The scale factor allows to increase the precession of the returned value. For
+ * a scale factor of 1 the function will return the result in the normal IIO
+ * unit for the channel type. E.g. millivolt for voltage channels, if you want
+ * nanovolts instead pass 1000 as the scale factor.
+ */
+int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
+	int *processed, unsigned int scale);
+
 #endif
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index be82936c4089..c0ae76ac4e0b 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -35,10 +35,13 @@ enum iio_chan_info_enum {
 	IIO_CHAN_INFO_FREQUENCY,
 	IIO_CHAN_INFO_PHASE,
 	IIO_CHAN_INFO_HARDWAREGAIN,
+	IIO_CHAN_INFO_HYSTERESIS,
 };
 
 #define IIO_CHAN_INFO_SHARED_BIT(type) BIT(type*2)
 #define IIO_CHAN_INFO_SEPARATE_BIT(type) BIT(type*2 + 1)
+#define IIO_CHAN_INFO_BITS(type) (IIO_CHAN_INFO_SHARED_BIT(type) | \
+				    IIO_CHAN_INFO_SEPARATE_BIT(type))
 
 #define IIO_CHAN_INFO_RAW_SEPARATE_BIT			\
 	IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_RAW)
@@ -100,6 +103,10 @@ enum iio_chan_info_enum {
 	IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_HARDWAREGAIN)
 #define IIO_CHAN_INFO_HARDWAREGAIN_SHARED_BIT			\
 	IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_HARDWAREGAIN)
+#define IIO_CHAN_INFO_HYSTERESIS_SEPARATE_BIT			\
+	IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_HYSTERESIS)
+#define IIO_CHAN_INFO_HYSTERESIS_SHARED_BIT			\
+	IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_HYSTERESIS)
 
 enum iio_endian {
 	IIO_CPU,
@@ -164,7 +171,7 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
  * IIO_ENUM() - Initialize enum extended channel attribute
  * @_name:	Attribute name
  * @_shared:	Whether the attribute is shared between all channels
- * @_e:		Pointer to a iio_enum struct
+ * @_e:		Pointer to an iio_enum struct
  *
  * This should usually be used together with IIO_ENUM_AVAILABLE()
  */
@@ -180,9 +187,9 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
 /**
  * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
  * @_name:	Attribute name ("_available" will be appended to the name)
- * @_e:		Pointer to a iio_enum struct
+ * @_e:		Pointer to an iio_enum struct
  *
- * Creates a read only attribute which list all the available enum items in a
+ * Creates a read only attribute which lists all the available enum items in a
  * space separated list. This should usually be used together with IIO_ENUM()
  */
 #define IIO_ENUM_AVAILABLE(_name, _e) \
@@ -229,6 +236,7 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
  * @indexed:		Specify the channel has a numerical index. If not,
  *			the channel index number will be suppressed for sysfs
  *			attributes but not for event codes.
+ * @output:		Channel is output.
  * @differential:	Channel is differential.
  */
 struct iio_chan_spec {
@@ -255,6 +263,21 @@ struct iio_chan_spec {
 	unsigned		differential:1;
 };
 
+
+/**
+ * iio_channel_has_info() - Checks whether a channel supports a info attribute
+ * @chan: The channel to be queried
+ * @type: Type of the info attribute to be checked
+ *
+ * Returns true if the channels supports reporting values for the given info
+ * attribute type, false otherwise.
+ */
+static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
+	enum iio_chan_info_enum type)
+{
+	return chan->info_mask & IIO_CHAN_INFO_BITS(type);
+}
+
 #define IIO_ST(si, rb, sb, sh)						\
 	{ .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
 
@@ -312,6 +335,9 @@ struct iio_dev;
  *			Meaning is event dependent.
  * @validate_trigger:	function to validate the trigger when the
  *			current trigger gets changed.
+ * @update_scan_mode:	function to configure device and scan buffer when
+ *			channels have changed
+ * @debugfs_reg_access:	function to read or write register value of device
  **/
 struct iio_info {
 	struct module			*driver_module;
@@ -367,10 +393,10 @@ struct iio_info {
  *			scan mask is valid for the device.
  */
 struct iio_buffer_setup_ops {
-	int				(*preenable)(struct iio_dev *);
-	int				(*postenable)(struct iio_dev *);
-	int				(*predisable)(struct iio_dev *);
-	int				(*postdisable)(struct iio_dev *);
+	int (*preenable)(struct iio_dev *);
+	int (*postenable)(struct iio_dev *);
+	int (*predisable)(struct iio_dev *);
+	int (*postdisable)(struct iio_dev *);
 	bool (*validate_scan_mask)(struct iio_dev *indio_dev,
 				   const unsigned long *scan_mask);
 };
@@ -516,6 +542,31 @@ static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
 	return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
 }
 
+
+/**
+ * iio_device_set_drvdata() - Set device driver data
+ * @indio_dev: IIO device structure
+ * @data: Driver specific data
+ *
+ * Allows to attach an arbitrary pointer to an IIO device, which can later be
+ * retrieved by iio_device_get_drvdata().
+ */
+static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
+{
+	dev_set_drvdata(&indio_dev->dev, data);
+}
+
+/**
+ * iio_device_get_drvdata() - Get device driver data
+ * @indio_dev: IIO device structure
+ *
+ * Returns the data previously set with iio_device_set_drvdata()
+ */
+static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev)
+{
+	return dev_get_drvdata(&indio_dev->dev);
+}
+
 /* Can we make this smaller? */
 #define IIO_ALIGN L1_CACHE_BYTES
 /**
diff --git a/include/linux/iio/kfifo_buf.h b/include/linux/iio/kfifo_buf.h
index 014d5a13b32b..25eeac762e84 100644
--- a/include/linux/iio/kfifo_buf.h
+++ b/include/linux/iio/kfifo_buf.h
@@ -1,3 +1,5 @@
+#ifndef __LINUX_IIO_KFIFO_BUF_H__
+#define __LINUX_IIO_KFIFO_BUF_H__
 
 #include <linux/kfifo.h>
 #include <linux/iio/iio.h>
@@ -6,3 +8,4 @@
 struct iio_buffer *iio_kfifo_allocate(struct iio_dev *indio_dev);
 void iio_kfifo_free(struct iio_buffer *r);
 
+#endif
diff --git a/include/linux/iio/machine.h b/include/linux/iio/machine.h
index 400a453ff67b..809a3f08d5a5 100644
--- a/include/linux/iio/machine.h
+++ b/include/linux/iio/machine.h
@@ -8,6 +8,9 @@
  * the Free Software Foundation.
  */
 
+#ifndef __LINUX_IIO_MACHINE_H__
+#define __LINUX_IIO_MACHINE_H__
+
 /**
  * struct iio_map - description of link between consumer and device channels
  * @adc_channel_label:	Label used to identify the channel on the provider.
@@ -22,3 +25,5 @@ struct iio_map {
 	const char *consumer_dev_name;
 	const char *consumer_channel;
 };
+
+#endif
diff --git a/include/linux/iio/trigger.h b/include/linux/iio/trigger.h
index a9819940a84c..20239da1d0f7 100644
--- a/include/linux/iio/trigger.h
+++ b/include/linux/iio/trigger.h
@@ -29,7 +29,7 @@ struct iio_subirq {
  * instances of a given device.
  **/
 struct iio_trigger_ops {
-	struct module			*owner;
+	struct module *owner;
 	int (*set_trigger_state)(struct iio_trigger *trig, bool state);
 	int (*try_reenable)(struct iio_trigger *trig);
 	int (*validate_device)(struct iio_trigger *trig,
@@ -39,7 +39,7 @@ struct iio_trigger_ops {
 
 /**
  * struct iio_trigger - industrial I/O trigger device
- *
+ * @ops:		[DRIVER] operations structure
  * @id:			[INTERN] unique id number
  * @name:		[DRIVER] unique name
  * @dev:		[DRIVER] associated device (if relevant)
@@ -76,19 +76,19 @@ struct iio_trigger {
 static inline struct iio_trigger *to_iio_trigger(struct device *d)
 {
 	return container_of(d, struct iio_trigger, dev);
-};
+}
 
 static inline void iio_trigger_put(struct iio_trigger *trig)
 {
 	module_put(trig->ops->owner);
 	put_device(&trig->dev);
-};
+}
 
 static inline void iio_trigger_get(struct iio_trigger *trig)
 {
 	get_device(&trig->dev);
 	__module_get(trig->ops->owner);
-};
+}
 
 /**
  * iio_trigger_register() - register a trigger with the IIO core
@@ -104,7 +104,8 @@ void iio_trigger_unregister(struct iio_trigger *trig_info);
 
 /**
  * iio_trigger_poll() - called on a trigger occurring
- * @trig: trigger which occurred
+ * @trig:	trigger which occurred
+ * @time:	timestamp when trigger occurred
  *
  * Typically called in relevant hardware interrupt handler.
  **/
diff --git a/include/linux/iio/trigger_consumer.h b/include/linux/iio/trigger_consumer.h
index 60d64b356945..c4f8c7409666 100644
--- a/include/linux/iio/trigger_consumer.h
+++ b/include/linux/iio/trigger_consumer.h
@@ -7,6 +7,15 @@
  * the Free Software Foundation.
  */
 
+#ifndef __LINUX_IIO_TRIGGER_CONSUMER_H__
+#define __LINUX_IIO_TRIGGER_CONSUMER_H__
+
+#include <linux/interrupt.h>
+#include <linux/types.h>
+
+struct iio_dev;
+struct iio_trigger;
+
 /**
  * struct iio_poll_func - poll function pair
  *
@@ -50,3 +59,5 @@ void iio_trigger_notify_done(struct iio_trigger *trig);
  */
 int iio_triggered_buffer_postenable(struct iio_dev *indio_dev);
 int iio_triggered_buffer_predisable(struct iio_dev *indio_dev);
+
+#endif
diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h
index 44e397705d7f..5c647ecfd5ba 100644
--- a/include/linux/iio/types.h
+++ b/include/linux/iio/types.h
@@ -57,5 +57,6 @@ enum iio_modifier {
 #define IIO_VAL_INT_PLUS_MICRO 2
 #define IIO_VAL_INT_PLUS_NANO 3
 #define IIO_VAL_INT_PLUS_MICRO_DB 4
+#define IIO_VAL_FRACTIONAL 10
 
 #endif /* _IIO_TYPES_H_ */