Device

Data Structures
struct	iio_device
	Represents a device in the IIO context. More...

Functions
__api __pure const char *	iio_device_get_id (const struct iio_device *dev)
	Retrieve the device ID (e.g. iio:device0) More...
__api __pure const char *	iio_device_get_name (const struct iio_device *dev)
	Retrieve the device name (e.g. xadc) More...
__api __pure unsigned int	iio_device_get_channels_count (const struct iio_device *dev)
	Enumerate the channels of the given device. More...
__api __pure unsigned int	iio_device_get_attrs_count (const struct iio_device *dev)
	Enumerate the device-specific attributes of the given device. More...
__api __pure struct iio_channel *	iio_device_get_channel (const struct iio_device *dev, unsigned int index)
	Get the channel present at the given index. More...
__api __pure const char *	iio_device_get_attr (const struct iio_device *dev, unsigned int index)
	Get the device-specific attribute present at the given index. More...
__api __pure struct iio_channel *	iio_device_find_channel (const struct iio_device *dev, const char *name, bool output)
	Try to find a channel structure by its name of ID. More...
__api __pure const char *	iio_device_find_attr (const struct iio_device *dev, const char *name)
	Try to find a device-specific attribute by its name. More...
__api ssize_t	iio_device_attr_read (const struct iio_device *dev, const char *attr, char *dst, size_t len)
	Read the content of the given device-specific attribute. More...
__api int	iio_device_attr_read_all (struct iio_device *dev, int(*cb)(struct iio_device *dev, const char *attr, const char *value, size_t len, void *d), void *data)
	Read the content of all device-specific attributes. More...
__api int	iio_device_attr_read_bool (const struct iio_device *dev, const char *attr, bool *val)
	Read the content of the given device-specific attribute. More...
__api int	iio_device_attr_read_longlong (const struct iio_device *dev, const char *attr, long long *val)
	Read the content of the given device-specific attribute. More...
__api int	iio_device_attr_read_double (const struct iio_device *dev, const char *attr, double *val)
	Read the content of the given device-specific attribute. More...
__api ssize_t	iio_device_attr_write (const struct iio_device *dev, const char *attr, const char *src)
	Set the value of the given device-specific attribute. More...
__api ssize_t	iio_device_attr_write_raw (const struct iio_device *dev, const char *attr, const void *src, size_t len)
	Set the value of the given device-specific attribute. More...
__api int	iio_device_attr_write_all (struct iio_device *dev, ssize_t(*cb)(struct iio_device *dev, const char *attr, void *buf, size_t len, void *d), void *data)
	Set the values of all device-specific attributes. More...
__api int	iio_device_attr_write_bool (const struct iio_device *dev, const char *attr, bool val)
	Set the value of the given device-specific attribute. More...
__api int	iio_device_attr_write_longlong (const struct iio_device *dev, const char *attr, long long val)
	Set the value of the given device-specific attribute. More...
__api int	iio_device_attr_write_double (const struct iio_device *dev, const char *attr, double val)
	Set the value of the given device-specific attribute. More...
__api void	iio_device_set_data (struct iio_device *dev, void *data)
	Associate a pointer to an iio_device structure. More...
__api void *	iio_device_get_data (const struct iio_device *dev)
	Retrieve a previously associated pointer of an iio_device structure. More...
__api int	iio_device_get_trigger (const struct iio_device *dev, const struct iio_device **trigger)
	Retrieve the trigger of a given device. More...
__api int	iio_device_set_trigger (const struct iio_device *dev, const struct iio_device *trigger)
	Associate a trigger to a given device. More...
__api __pure bool	iio_device_is_trigger (const struct iio_device *dev)
	Return True if the given device is a trigger. More...

Detailed Description

Function Documentation

iio_device_attr_read()

__api ssize_t iio_device_attr_read	(	const struct iio_device *	dev,
		const char *	attr,
		char *	dst,
		size_t	len
	)

Read the content of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
dst	A pointer to the memory area where the NULL-terminated string corresponding to the value read will be stored
len	The available length of the memory area, in bytes

Returns

On success, the number of bytes written to the buffer

On error, a negative errno code is returned

NOTE:By passing NULL as the "attr" argument to iio_device_attr_read, it is now possible to read all of the attributes of a device.

The buffer is filled with one block of data per attribute of the device, by the order they appear in the iio_device structure.

The first four bytes of one block correspond to a 32-bit signed value in network order. If negative, it corresponds to the errno code that were returned when reading the attribute; if positive, it corresponds to the length of the data read. In that case, the rest of the block contains the data.

iio_device_attr_read_all()

__api int iio_device_attr_read_all	(	struct iio_device *	dev,
		int(*)(struct iio_device *dev, const char *attr, const char *value, size_t len, void *d)	cb,
		void *	data
	)

Read the content of all device-specific attributes.

Parameters

dev	A pointer to an iio_device structure
cb	A pointer to a callback function
data	A pointer that will be passed to the callback function

Returns

On success, 0 is returned

On error, a negative errno code is returned

NOTE: This function is especially useful when used with the network backend, as all the device-specific attributes are read in one single command.

iio_device_attr_read_bool()

__api int iio_device_attr_read_bool	(	const struct iio_device *	dev,
		const char *	attr,
		bool *	val
	)

Read the content of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
val	A pointer to a bool variable where the value should be stored

Returns

On success, 0 is returned

On error, a negative errno code is returned

iio_device_attr_read_double()

__api int iio_device_attr_read_double	(	const struct iio_device *	dev,
		const char *	attr,
		double *	val
	)

Read the content of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
val	A pointer to a double variable where the value should be stored

Returns

On success, 0 is returned

On error, a negative errno code is returned

iio_device_attr_read_longlong()

__api int iio_device_attr_read_longlong	(	const struct iio_device *	dev,
		const char *	attr,
		long long *	val
	)

Read the content of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
val	A pointer to a long long variable where the value should be stored

Returns

On success, 0 is returned

On error, a negative errno code is returned

iio_device_attr_write()

__api ssize_t iio_device_attr_write	(	const struct iio_device *	dev,
		const char *	attr,
		const char *	src
	)

Set the value of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
src	A NULL-terminated string to set the attribute to

Returns

On success, the number of bytes written

On error, a negative errno code is returned

NOTE:By passing NULL as the "attr" argument to iio_device_attr_write, it is now possible to write all of the attributes of a device.

The buffer must contain one block of data per attribute of the device, by the order they appear in the iio_device structure.

The first four bytes of one block correspond to a 32-bit signed value in network order. If negative, the attribute is not written; if positive, it corresponds to the length of the data to write. In that case, the rest of the block must contain the data.

iio_device_attr_write_all()

__api int iio_device_attr_write_all	(	struct iio_device *	dev,
		ssize_t(*)(struct iio_device *dev, const char *attr, void *buf, size_t len, void *d)	cb,
		void *	data
	)

Set the values of all device-specific attributes.

Parameters

dev	A pointer to an iio_device structure
cb	A pointer to a callback function
data	A pointer that will be passed to the callback function

Returns

On success, 0 is returned

On error, a negative errno code is returned

NOTE: This function is especially useful when used with the network backend, as all the device-specific attributes are written in one single command.

iio_device_attr_write_bool()

__api int iio_device_attr_write_bool	(	const struct iio_device *	dev,
		const char *	attr,
		bool	val
	)

Set the value of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
val	A bool value to set the attribute to

Returns

On success, 0 is returned

On error, a negative errno code is returned

iio_device_attr_write_double()

__api int iio_device_attr_write_double	(	const struct iio_device *	dev,
		const char *	attr,
		double	val
	)

Set the value of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
val	A double value to set the attribute to

Returns

On success, 0 is returned

On error, a negative errno code is returned

iio_device_attr_write_longlong()

__api int iio_device_attr_write_longlong	(	const struct iio_device *	dev,
		const char *	attr,
		long long	val
	)

Set the value of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
val	A long long value to set the attribute to

Returns

On success, 0 is returned

On error, a negative errno code is returned

iio_device_attr_write_raw()

__api ssize_t iio_device_attr_write_raw	(	const struct iio_device *	dev,
		const char *	attr,
		const void *	src,
		size_t	len
	)

Set the value of the given device-specific attribute.

Parameters

dev	A pointer to an iio_device structure
attr	A NULL-terminated string corresponding to the name of the attribute
src	A pointer to the data to be written
len	The number of bytes that should be written

Returns

On success, the number of bytes written

On error, a negative errno code is returned

iio_device_find_attr()

__api __pure const char* iio_device_find_attr	(	const struct iio_device *	dev,
		const char *	name
	)

Try to find a device-specific attribute by its name.

Parameters

dev	A pointer to an iio_device structure
name	A NULL-terminated string corresponding to the name of the attribute

Returns

On success, a pointer to a static NULL-terminated string

If the name does not correspond to any known attribute of the given device, NULL is returned

NOTE: This function is useful to detect the presence of an attribute. It can also be used to retrieve the name of an attribute as a pointer to a static string from a dynamically allocated string.

iio_device_find_channel()

__api __pure struct iio_channel* iio_device_find_channel	(	const struct iio_device *	dev,
		const char *	name,
		bool	output
	)

Try to find a channel structure by its name of ID.

Parameters

dev	A pointer to an iio_device structure
name	A NULL-terminated string corresponding to the name or the ID of the channel to search for
output	True if the searched channel is output, False otherwise

Returns

On success, a pointer to an iio_channel structure

If the name or ID does not correspond to any known channel of the given device, NULL is returned

iio_device_get_attr()

__api __pure const char* iio_device_get_attr	(	const struct iio_device *	dev,
		unsigned int	index
	)

Get the device-specific attribute present at the given index.

Parameters

dev	A pointer to an iio_device structure
index	The index corresponding to the attribute

Returns

On success, a pointer to a static NULL-terminated string

If the index is invalid, NULL is returned

iio_device_get_attrs_count()

__api __pure unsigned int iio_device_get_attrs_count

(

const struct iio_device *

dev

)

Enumerate the device-specific attributes of the given device.

Parameters

dev	A pointer to an iio_device structure

Returns

The number of device-specific attributes found

iio_device_get_channel()

__api __pure struct iio_channel* iio_device_get_channel	(	const struct iio_device *	dev,
		unsigned int	index
	)

Get the channel present at the given index.

Parameters

dev	A pointer to an iio_device structure
index	The index corresponding to the channel

Returns

On success, a pointer to an iio_channel structure

If the index is invalid, NULL is returned

iio_device_get_channels_count()

__api __pure unsigned int iio_device_get_channels_count

(

const struct iio_device *

dev

)

Enumerate the channels of the given device.

Parameters

dev	A pointer to an iio_device structure

Returns

The number of channels found

iio_device_get_data()

__api void* iio_device_get_data

(

const struct iio_device *

dev

)

Retrieve a previously associated pointer of an iio_device structure.

Parameters

dev	A pointer to an iio_device structure

Returns

The pointer previously associated if present, or NULL

iio_device_get_id()

__api __pure const char* iio_device_get_id

(

const struct iio_device *

dev

)

Retrieve the device ID (e.g. iio:device0)

Parameters

dev	A pointer to an iio_device structure

Returns

A pointer to a static NULL-terminated string

iio_device_get_name()

__api __pure const char* iio_device_get_name

(

const struct iio_device *

dev

)

Retrieve the device name (e.g. xadc)

Parameters

dev	A pointer to an iio_device structure

Returns

A pointer to a static NULL-terminated string

NOTE: if the device has no name, NULL is returned.

iio_device_get_trigger()

__api int iio_device_get_trigger	(	const struct iio_device *	dev,
		const struct iio_device **	trigger
	)

Retrieve the trigger of a given device.

Parameters

dev	A pointer to an iio_device structure
trigger	a pointer to a pointer of an iio_device structure. The pointed pointer will be set to the address of the iio_device structure corresponding to the associated trigger device.

Returns

On success, 0 is returned

On error, a negative errno code is returned

iio_device_is_trigger()

__api __pure bool iio_device_is_trigger

(

const struct iio_device *

dev

)

Return True if the given device is a trigger.

Parameters

dev	A pointer to an iio_device structure

Returns

True if the device is a trigger, False otherwise

iio_device_set_data()

__api void iio_device_set_data	(	struct iio_device *	dev,
		void *	data
	)

Associate a pointer to an iio_device structure.

Parameters

dev	A pointer to an iio_device structure
data	The pointer to be associated

iio_device_set_trigger()

__api int iio_device_set_trigger	(	const struct iio_device *	dev,
		const struct iio_device *	trigger
	)

Associate a trigger to a given device.

Parameters

dev	A pointer to an iio_device structure
trigger	a pointer to the iio_device structure corresponding to the trigger that should be associated.

Returns

On success, 0 is returned

On error, a negative errno code is returned