Initial import

1 files changed, 652 insertions, 0 deletions

diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
new file mode 100644
index 000000000..d86b753e9
--- /dev/null
+++ b/include/linux/iio/iio.h
@@ -0,0 +1,652 @@
+
+/* The industrial I/O core
+ *
+ * Copyright (c) 2008 Jonathan Cameron
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+#ifndef _INDUSTRIAL_IO_H_
+#define _INDUSTRIAL_IO_H_
+
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include <linux/iio/types.h>
+#include <linux/of.h>
+/* IIO TODO LIST */
+/*
+ * Provide means of adjusting timer accuracy.
+ * Currently assumes nano seconds.
+ */
+
+enum iio_chan_info_enum {
+	IIO_CHAN_INFO_RAW = 0,
+	IIO_CHAN_INFO_PROCESSED,
+	IIO_CHAN_INFO_SCALE,
+	IIO_CHAN_INFO_OFFSET,
+	IIO_CHAN_INFO_CALIBSCALE,
+	IIO_CHAN_INFO_CALIBBIAS,
+	IIO_CHAN_INFO_PEAK,
+	IIO_CHAN_INFO_PEAK_SCALE,
+	IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW,
+	IIO_CHAN_INFO_AVERAGE_RAW,
+	IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY,
+	IIO_CHAN_INFO_SAMP_FREQ,
+	IIO_CHAN_INFO_FREQUENCY,
+	IIO_CHAN_INFO_PHASE,
+	IIO_CHAN_INFO_HARDWAREGAIN,
+	IIO_CHAN_INFO_HYSTERESIS,
+	IIO_CHAN_INFO_INT_TIME,
+	IIO_CHAN_INFO_ENABLE,
+	IIO_CHAN_INFO_CALIBHEIGHT,
+	IIO_CHAN_INFO_CALIBWEIGHT,
+	IIO_CHAN_INFO_DEBOUNCE_COUNT,
+	IIO_CHAN_INFO_DEBOUNCE_TIME,
+};
+
+enum iio_shared_by {
+	IIO_SEPARATE,
+	IIO_SHARED_BY_TYPE,
+	IIO_SHARED_BY_DIR,
+	IIO_SHARED_BY_ALL
+};
+
+enum iio_endian {
+	IIO_CPU,
+	IIO_BE,
+	IIO_LE,
+};
+
+struct iio_chan_spec;
+struct iio_dev;
+
+/**
+ * struct iio_chan_spec_ext_info - Extended channel info attribute
+ * @name:	Info attribute name
+ * @shared:	Whether this attribute is shared between all channels.
+ * @read:	Read callback for this info attribute, may be NULL.
+ * @write:	Write callback for this info attribute, may be NULL.
+ * @private:	Data private to the driver.
+ */
+struct iio_chan_spec_ext_info {
+	const char *name;
+	enum iio_shared_by shared;
+	ssize_t (*read)(struct iio_dev *, uintptr_t private,
+			struct iio_chan_spec const *, char *buf);
+	ssize_t (*write)(struct iio_dev *, uintptr_t private,
+			 struct iio_chan_spec const *, const char *buf,
+			 size_t len);
+	uintptr_t private;
+};
+
+/**
+ * struct iio_enum - Enum channel info attribute
+ * @items:	An array of strings.
+ * @num_items:	Length of the item array.
+ * @set:	Set callback function, may be NULL.
+ * @get:	Get callback function, may be NULL.
+ *
+ * The iio_enum struct can be used to implement enum style channel attributes.
+ * Enum style attributes are those which have a set of strings which map to
+ * unsigned integer values. The IIO enum helper code takes care of mapping
+ * between value and string as well as generating a "_available" file which
+ * contains a list of all available items. The set callback will be called when
+ * the attribute is updated. The last parameter is the index to the newly
+ * activated item. The get callback will be used to query the currently active
+ * item and is supposed to return the index for it.
+ */
+struct iio_enum {
+	const char * const *items;
+	unsigned int num_items;
+	int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
+	int (*get)(struct iio_dev *, const struct iio_chan_spec *);
+};
+
+ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
+	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
+ssize_t iio_enum_read(struct iio_dev *indio_dev,
+	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
+ssize_t iio_enum_write(struct iio_dev *indio_dev,
+	uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
+	size_t len);
+
+/**
+ * IIO_ENUM() - Initialize enum extended channel attribute
+ * @_name:	Attribute name
+ * @_shared:	Whether the attribute is shared between all channels
+ * @_e:		Pointer to an iio_enum struct
+ *
+ * This should usually be used together with IIO_ENUM_AVAILABLE()
+ */
+#define IIO_ENUM(_name, _shared, _e) \
+{ \
+	.name = (_name), \
+	.shared = (_shared), \
+	.read = iio_enum_read, \
+	.write = iio_enum_write, \
+	.private = (uintptr_t)(_e), \
+}
+
+/**
+ * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
+ * @_name:	Attribute name ("_available" will be appended to the name)
+ * @_e:		Pointer to an iio_enum struct
+ *
+ * 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) \
+{ \
+	.name = (_name "_available"), \
+	.shared = IIO_SHARED_BY_TYPE, \
+	.read = iio_enum_available_read, \
+	.private = (uintptr_t)(_e), \
+}
+
+/**
+ * struct iio_event_spec - specification for a channel event
+ * @type:		    Type of the event
+ * @dir:		    Direction of the event
+ * @mask_separate:	    Bit mask of enum iio_event_info values. Attributes
+ *			    set in this mask will be registered per channel.
+ * @mask_shared_by_type:    Bit mask of enum iio_event_info values. Attributes
+ *			    set in this mask will be shared by channel type.
+ * @mask_shared_by_dir:	    Bit mask of enum iio_event_info values. Attributes
+ *			    set in this mask will be shared by channel type and
+ *			    direction.
+ * @mask_shared_by_all:	    Bit mask of enum iio_event_info values. Attributes
+ *			    set in this mask will be shared by all channels.
+ */
+struct iio_event_spec {
+	enum iio_event_type type;
+	enum iio_event_direction dir;
+	unsigned long mask_separate;
+	unsigned long mask_shared_by_type;
+	unsigned long mask_shared_by_dir;
+	unsigned long mask_shared_by_all;
+};
+
+/**
+ * struct iio_chan_spec - specification of a single channel
+ * @type:		What type of measurement is the channel making.
+ * @channel:		What number do we wish to assign the channel.
+ * @channel2:		If there is a second number for a differential
+ *			channel then this is it. If modified is set then the
+ *			value here specifies the modifier.
+ * @address:		Driver specific identifier.
+ * @scan_index:		Monotonic index to give ordering in scans when read
+ *			from a buffer.
+ * @scan_type:		Sign:		's' or 'u' to specify signed or unsigned
+ *			realbits:	Number of valid bits of data
+ *			storage_bits:	Realbits + padding
+ *			shift:		Shift right by this before masking out
+ *					realbits.
+ *			endianness:	little or big endian
+ *			repeat:		Number of times real/storage bits
+ *					repeats. When the repeat element is
+ *					more than 1, then the type element in
+ *					sysfs will show a repeat value.
+ *					Otherwise, the number of repetitions is
+ *					omitted.
+ * @info_mask_separate: What information is to be exported that is specific to
+ *			this channel.
+ * @info_mask_shared_by_type: What information is to be exported that is shared
+ *			by all channels of the same type.
+ * @info_mask_shared_by_dir: What information is to be exported that is shared
+ *			by all channels of the same direction.
+ * @info_mask_shared_by_all: What information is to be exported that is shared
+ *			by all channels.
+ * @event_spec:		Array of events which should be registered for this
+ *			channel.
+ * @num_event_specs:	Size of the event_spec array.
+ * @ext_info:		Array of extended info attributes for this channel.
+ *			The array is NULL terminated, the last element should
+ *			have its name field set to NULL.
+ * @extend_name:	Allows labeling of channel attributes with an
+ *			informative name. Note this has no effect codes etc,
+ *			unlike modifiers.
+ * @datasheet_name:	A name used in in-kernel mapping of channels. It should
+ *			correspond to the first name that the channel is referred
+ *			to by in the datasheet (e.g. IND), or the nearest
+ *			possible compound name (e.g. IND-INC).
+ * @modified:		Does a modifier apply to this channel. What these are
+ *			depends on the channel type.  Modifier is set in
+ *			channel2. Examples are IIO_MOD_X for axial sensors about
+ *			the 'x' axis.
+ * @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 {
+	enum iio_chan_type	type;
+	int			channel;
+	int			channel2;
+	unsigned long		address;
+	int			scan_index;
+	struct {
+		char	sign;
+		u8	realbits;
+		u8	storagebits;
+		u8	shift;
+		u8	repeat;
+		enum iio_endian endianness;
+	} scan_type;
+	long			info_mask_separate;
+	long			info_mask_shared_by_type;
+	long			info_mask_shared_by_dir;
+	long			info_mask_shared_by_all;
+	const struct iio_event_spec *event_spec;
+	unsigned int		num_event_specs;
+	const struct iio_chan_spec_ext_info *ext_info;
+	const char		*extend_name;
+	const char		*datasheet_name;
+	unsigned		modified:1;
+	unsigned		indexed:1;
+	unsigned		output:1;
+	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_separate & BIT(type)) |
+		(chan->info_mask_shared_by_type & BIT(type)) |
+		(chan->info_mask_shared_by_dir & BIT(type)) |
+		(chan->info_mask_shared_by_all & BIT(type));
+}
+
+#define IIO_CHAN_SOFT_TIMESTAMP(_si) {					\
+	.type = IIO_TIMESTAMP,						\
+	.channel = -1,							\
+	.scan_index = _si,						\
+	.scan_type = {							\
+		.sign = 's',						\
+		.realbits = 64,					\
+		.storagebits = 64,					\
+		},							\
+}
+
+/**
+ * iio_get_time_ns() - utility function to get a time stamp for events etc
+ **/
+static inline s64 iio_get_time_ns(void)
+{
+	return ktime_get_real_ns();
+}
+
+/* Device operating modes */
+#define INDIO_DIRECT_MODE		0x01
+#define INDIO_BUFFER_TRIGGERED		0x02
+#define INDIO_BUFFER_SOFTWARE		0x04
+#define INDIO_BUFFER_HARDWARE		0x08
+
+#define INDIO_ALL_BUFFER_MODES					\
+	(INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE | INDIO_BUFFER_SOFTWARE)
+
+#define INDIO_MAX_RAW_ELEMENTS		4
+
+struct iio_trigger; /* forward declaration */
+struct iio_dev;
+
+/**
+ * struct iio_info - constant information about device
+ * @driver_module:	module structure used to ensure correct
+ *			ownership of chrdevs etc
+ * @event_attrs:	event control attributes
+ * @attrs:		general purpose device attributes
+ * @read_raw:		function to request a value from the device.
+ *			mask specifies which value. Note 0 means a reading of
+ *			the channel in question.  Return value will specify the
+ *			type of value returned by the device. val and val2 will
+ *			contain the elements making up the returned value.
+ * @read_raw_multi:	function to return values from the device.
+ *			mask specifies which value. Note 0 means a reading of
+ *			the channel in question.  Return value will specify the
+ *			type of value returned by the device. vals pointer
+ *			contain the elements making up the returned value.
+ *			max_len specifies maximum number of elements
+ *			vals pointer can contain. val_len is used to return
+ *			length of valid elements in vals.
+ * @write_raw:		function to write a value to the device.
+ *			Parameters are the same as for read_raw.
+ * @write_raw_get_fmt:	callback function to query the expected
+ *			format/precision. If not set by the driver, write_raw
+ *			returns IIO_VAL_INT_PLUS_MICRO.
+ * @read_event_config:	find out if the event is enabled.
+ * @write_event_config:	set if the event is enabled.
+ * @read_event_value:	read a configuration value associated with the event.
+ * @write_event_value:	write a configuration value for the event.
+ * @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
+ * @of_xlate:		function pointer to obtain channel specifier index.
+ *			When #iio-cells is greater than '0', the driver could
+ *			provide a custom of_xlate function that reads the
+ *			*args* and returns the appropriate index in registered
+ *			IIO channels array.
+ * @hwfifo_set_watermark: function pointer to set the current hardware
+ *			fifo watermark level; see hwfifo_* entries in
+ *			Documentation/ABI/testing/sysfs-bus-iio for details on
+ *			how the hardware fifo operates
+ * @hwfifo_flush_to_buffer: function pointer to flush the samples stored
+ *			in the hardware fifo to the device buffer. The driver
+ *			should not flush more than count samples. The function
+ *			must return the number of samples flushed, 0 if no
+ *			samples were flushed or a negative integer if no samples
+ *			were flushed and there was an error.
+ **/
+struct iio_info {
+	struct module			*driver_module;
+	struct attribute_group		*event_attrs;
+	const struct attribute_group	*attrs;
+
+	int (*read_raw)(struct iio_dev *indio_dev,
+			struct iio_chan_spec const *chan,
+			int *val,
+			int *val2,
+			long mask);
+
+	int (*read_raw_multi)(struct iio_dev *indio_dev,
+			struct iio_chan_spec const *chan,
+			int max_len,
+			int *vals,
+			int *val_len,
+			long mask);
+
+	int (*write_raw)(struct iio_dev *indio_dev,
+			 struct iio_chan_spec const *chan,
+			 int val,
+			 int val2,
+			 long mask);
+
+	int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
+			 struct iio_chan_spec const *chan,
+			 long mask);
+
+	int (*read_event_config)(struct iio_dev *indio_dev,
+				 const struct iio_chan_spec *chan,
+				 enum iio_event_type type,
+				 enum iio_event_direction dir);
+
+	int (*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);
+
+	int (*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);
+
+	int (*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);
+
+	int (*validate_trigger)(struct iio_dev *indio_dev,
+				struct iio_trigger *trig);
+	int (*update_scan_mode)(struct iio_dev *indio_dev,
+				const unsigned long *scan_mask);
+	int (*debugfs_reg_access)(struct iio_dev *indio_dev,
+				  unsigned reg, unsigned writeval,
+				  unsigned *readval);
+	int (*of_xlate)(struct iio_dev *indio_dev,
+			const struct of_phandle_args *iiospec);
+	int (*hwfifo_set_watermark)(struct iio_dev *indio_dev, unsigned val);
+	int (*hwfifo_flush_to_buffer)(struct iio_dev *indio_dev,
+				      unsigned count);
+};
+
+/**
+ * struct iio_buffer_setup_ops - buffer setup related callbacks
+ * @preenable:		[DRIVER] function to run prior to marking buffer enabled
+ * @postenable:		[DRIVER] function to run after marking buffer enabled
+ * @predisable:		[DRIVER] function to run prior to marking buffer
+ *			disabled
+ * @postdisable:	[DRIVER] function to run after marking buffer disabled
+ * @validate_scan_mask: [DRIVER] function callback to check whether a given
+ *			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 *);
+	bool (*validate_scan_mask)(struct iio_dev *indio_dev,
+				   const unsigned long *scan_mask);
+};
+
+/**
+ * struct iio_dev - industrial I/O device
+ * @id:			[INTERN] used to identify device internally
+ * @modes:		[DRIVER] operating modes supported by device
+ * @currentmode:	[DRIVER] current operating mode
+ * @dev:		[DRIVER] device structure, should be assigned a parent
+ *			and owner
+ * @event_interface:	[INTERN] event chrdevs associated with interrupt lines
+ * @buffer:		[DRIVER] any buffer present
+ * @buffer_list:	[INTERN] list of all buffers currently attached
+ * @scan_bytes:		[INTERN] num bytes captured to be fed to buffer demux
+ * @mlock:		[INTERN] lock used to prevent simultaneous device state
+ *			changes
+ * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
+ * @masklength:		[INTERN] the length of the mask established from
+ *			channels
+ * @active_scan_mask:	[INTERN] union of all scan masks requested by buffers
+ * @scan_timestamp:	[INTERN] set if any buffers have requested timestamp
+ * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
+ * @trig:		[INTERN] current device trigger (buffer modes)
+ * @pollfunc:		[DRIVER] function run on trigger being received
+ * @channels:		[DRIVER] channel specification structure table
+ * @num_channels:	[DRIVER] number of channels specified in @channels.
+ * @channel_attr_list:	[INTERN] keep track of automatically created channel
+ *			attributes
+ * @chan_attr_group:	[INTERN] group for all attrs in base directory
+ * @name:		[DRIVER] name of the device.
+ * @info:		[DRIVER] callbacks and constant info from driver
+ * @info_exist_lock:	[INTERN] lock to prevent use during removal
+ * @setup_ops:		[DRIVER] callbacks to call before and after buffer
+ *			enable/disable
+ * @chrdev:		[INTERN] associated character device
+ * @groups:		[INTERN] attribute groups
+ * @groupcounter:	[INTERN] index of next attribute group
+ * @flags:		[INTERN] file ops related flags including busy flag.
+ * @debugfs_dentry:	[INTERN] device specific debugfs dentry.
+ * @cached_reg_addr:	[INTERN] cached register address for debugfs reads.
+ */
+struct iio_dev {
+	int				id;
+
+	int				modes;
+	int				currentmode;
+	struct device			dev;
+
+	struct iio_event_interface	*event_interface;
+
+	struct iio_buffer		*buffer;
+	struct list_head		buffer_list;
+	int				scan_bytes;
+	struct mutex			mlock;
+
+	const unsigned long		*available_scan_masks;
+	unsigned			masklength;
+	const unsigned long		*active_scan_mask;
+	bool				scan_timestamp;
+	unsigned			scan_index_timestamp;
+	struct iio_trigger		*trig;
+	struct iio_poll_func		*pollfunc;
+
+	struct iio_chan_spec const	*channels;
+	int				num_channels;
+
+	struct list_head		channel_attr_list;
+	struct attribute_group		chan_attr_group;
+	const char			*name;
+	const struct iio_info		*info;
+	struct mutex			info_exist_lock;
+	const struct iio_buffer_setup_ops	*setup_ops;
+	struct cdev			chrdev;
+#define IIO_MAX_GROUPS 6
+	const struct attribute_group	*groups[IIO_MAX_GROUPS + 1];
+	int				groupcounter;
+
+	unsigned long			flags;
+#if defined(CONFIG_DEBUG_FS)
+	struct dentry			*debugfs_dentry;
+	unsigned			cached_reg_addr;
+#endif
+};
+
+const struct iio_chan_spec
+*iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
+int iio_device_register(struct iio_dev *indio_dev);
+void iio_device_unregister(struct iio_dev *indio_dev);
+int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev);
+void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev);
+int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
+
+extern struct bus_type iio_bus_type;
+
+/**
+ * iio_device_put() - reference counted deallocation of struct device
+ * @indio_dev: 		IIO device structure containing the device
+ **/
+static inline void iio_device_put(struct iio_dev *indio_dev)
+{
+	if (indio_dev)
+		put_device(&indio_dev->dev);
+}
+
+/**
+ * dev_to_iio_dev() - Get IIO device struct from a device struct
+ * @dev: 		The device embedded in the IIO device
+ *
+ * Note: The device must be a IIO device, otherwise the result is undefined.
+ */
+static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
+{
+	return container_of(dev, struct iio_dev, dev);
+}
+
+/**
+ * iio_device_get() - increment reference count for the device
+ * @indio_dev: 		IIO device structure
+ *
+ * Returns: The passed IIO device
+ **/
+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
+struct iio_dev *iio_device_alloc(int sizeof_priv);
+
+static inline void *iio_priv(const struct iio_dev *indio_dev)
+{
+	return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
+}
+
+static inline struct iio_dev *iio_priv_to_dev(void *priv)
+{
+	return (struct iio_dev *)((char *)priv -
+				  ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
+}
+
+void iio_device_free(struct iio_dev *indio_dev);
+struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv);
+void devm_iio_device_free(struct device *dev, struct iio_dev *indio_dev);
+struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
+						const char *fmt, ...);
+void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig);
+
+/**
+ * iio_buffer_enabled() - helper function to test if the buffer is enabled
+ * @indio_dev:		IIO device structure for device
+ **/
+static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
+{
+	return indio_dev->currentmode
+		& (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE |
+		   INDIO_BUFFER_SOFTWARE);
+}
+
+/**
+ * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
+ * @indio_dev:		IIO device structure for device
+ **/
+#if defined(CONFIG_DEBUG_FS)
+static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
+{
+	return indio_dev->debugfs_dentry;
+}
+#else
+static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
+{
+	return NULL;
+}
+#endif
+
+int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
+	int *fract);
+
+/**
+ * IIO_DEGREE_TO_RAD() - Convert degree to rad
+ * @deg: A value in degree
+ *
+ * Returns the given value converted from degree to rad
+ */
+#define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
+
+/**
+ * IIO_G_TO_M_S_2() - Convert g to meter / second**2
+ * @g: A value in g
+ *
+ * Returns the given value converted from g to meter / second**2
+ */
+#define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
+
+#endif /* _INDUSTRIAL_IO_H_ */