ADC driver APIs . More...

Topics
	Emulated ADC
	Emulated ADC backend API .

Data Structures
struct	adc_channel_cfg
	Structure for specifying the configuration of an ADC channel. More...

struct	adc_dt_spec
	Container for ADC channel information specified in devicetree. More...

struct	adc_sequence_options
	Structure defining additional options for an ADC sampling sequence. More...

struct	adc_sequence
	Structure defining an ADC sampling sequence. More...

struct	adc_driver_api
	ADC driver API. More...

Macros
#define	ADC_CHANNEL_CFG_DT(node_id)
	Get ADC channel configuration from a given devicetree node.

#define	ADC_DT_SPEC_GET_BY_NAME(node_id, name)
	Get ADC io-channel information from devicetree by name.

#define	ADC_DT_SPEC_INST_GET_BY_NAME(inst, name)
	Get ADC io-channel information from a DT_DRV_COMPAT devicetree instance by name.

#define	ADC_DT_SPEC_GET_BY_IDX(node_id, idx)
	Get ADC io-channel information from devicetree.

#define	ADC_DT_SPEC_INST_GET_BY_IDX(inst, idx)
	Get ADC io-channel information from a DT_DRV_COMPAT devicetree instance.

#define	ADC_DT_SPEC_GET(node_id)
	Equivalent to ADC_DT_SPEC_GET_BY_IDX(node_id, 0).

#define	ADC_DT_SPEC_INST_GET(inst)
	Equivalent to ADC_DT_SPEC_INST_GET_BY_IDX(inst, 0).

Typedefs
typedef enum adc_action(*	adc_sequence_callback) (const struct device dev, const struct adc_sequence sequence, uint16_t sampling_index)
	Type definition of the optional callback function to be called after a requested sampling is done.

typedef int(*	adc_api_channel_setup) (const struct device dev, const struct adc_channel_cfg channel_cfg)
	Type definition of ADC API function for configuring a channel.

typedef int(*	adc_api_read) (const struct device dev, const struct adc_sequence sequence)
	Type definition of ADC API function for setting a read request.

typedef int(*	adc_api_read_async) (const struct device dev, const struct adc_sequence sequence, struct k_poll_signal *async)
	Type definition of ADC API function for setting an asynchronous read request.

Enumerations
enum	adc_gain { ADC_GAIN_1_6 , ADC_GAIN_1_5 , ADC_GAIN_1_4 , ADC_GAIN_1_3 , ADC_GAIN_2_5 , ADC_GAIN_1_2 , ADC_GAIN_2_3 , ADC_GAIN_4_5 , ADC_GAIN_1 , ADC_GAIN_2 , ADC_GAIN_3 , ADC_GAIN_4 , ADC_GAIN_6 , ADC_GAIN_8 , ADC_GAIN_12 , ADC_GAIN_16 , ADC_GAIN_24 , ADC_GAIN_32 , ADC_GAIN_64 , ADC_GAIN_128 }
	ADC channel gain factors. More...

enum	adc_reference { ADC_REF_VDD_1 , ADC_REF_VDD_1_2 , ADC_REF_VDD_1_3 , ADC_REF_VDD_1_4 , ADC_REF_INTERNAL , ADC_REF_EXTERNAL0 , ADC_REF_EXTERNAL1 }
	ADC references. More...

enum	adc_action { ADC_ACTION_CONTINUE = 0 , ADC_ACTION_REPEAT , ADC_ACTION_FINISH }
	Action to be performed after a sampling is done. More...

Functions
int	adc_gain_invert (enum adc_gain gain, int32_t *value)
	Invert the application of gain to a measurement value.

int	adc_channel_setup (const struct device dev, const struct adc_channel_cfg channel_cfg)
	Configure an ADC channel.

static int	adc_channel_setup_dt (const struct adc_dt_spec *spec)
	Configure an ADC channel from a struct adc_dt_spec.

int	adc_read (const struct device dev, const struct adc_sequence sequence)
	Set a read request.

static int	adc_read_dt (const struct adc_dt_spec spec, const struct adc_sequence sequence)
	Set a read request from a struct adc_dt_spec.

int	adc_read_async (const struct device dev, const struct adc_sequence sequence, struct k_poll_signal *async)
	Set an asynchronous read request.

static uint16_t	adc_ref_internal (const struct device *dev)
	Get the internal reference voltage.

static int	adc_raw_to_millivolts (int32_t ref_mv, enum adc_gain gain, uint8_t resolution, int32_t *valp)
	Convert a raw ADC value to millivolts.

static int	adc_raw_to_millivolts_dt (const struct adc_dt_spec spec, int32_t valp)
	Convert a raw ADC value to millivolts using information stored in a struct adc_dt_spec.

static int	adc_sequence_init_dt (const struct adc_dt_spec spec, struct adc_sequence seq)
	Initialize a struct adc_sequence from information stored in struct adc_dt_spec.

static bool	adc_is_ready_dt (const struct adc_dt_spec *spec)
	Validate that the ADC device is ready.

Detailed Description

ADC driver APIs .

Since: 1.0

Version: 1.0.0

Macro Definition Documentation

◆ ADC_CHANNEL_CFG_DT

#define ADC_CHANNEL_CFG_DT ( node_id )

#include <zephyr/drivers/adc.h>

Value:

        { \
        .gain             = DT_STRING_TOKEN(node_id, zephyr_gain), \
        .reference        = DT_STRING_TOKEN(node_id, zephyr_reference), \
        .acquisition_time = DT_PROP(node_id, zephyr_acquisition_time), \
        .channel_id       = DT_REG_ADDR(node_id), \
IF_ENABLED(UTIL_OR(DT_PROP(node_id, zephyr_differential), \
                   UTIL_AND(CONFIG_ADC_CONFIGURABLE_INPUTS, \
                            DT_NODE_HAS_PROP(node_id, zephyr_input_negative))), \
        (.differential    = true,)) \
IF_ENABLED(CONFIG_ADC_CONFIGURABLE_INPUTS, \
        (.input_positive  = DT_PROP_OR(node_id, zephyr_input_positive, 0), \
         .input_negative  = DT_PROP_OR(node_id, zephyr_input_negative, 0),)) \
IF_ENABLED(CONFIG_ADC_CONFIGURABLE_EXCITATION_CURRENT_SOURCE_PIN, \
        (.current_source_pin_set = DT_NODE_HAS_PROP(node_id, zephyr_current_source_pin), \
         .current_source_pin = DT_PROP_OR(node_id, zephyr_current_source_pin, {0}),)) \
IF_ENABLED(CONFIG_ADC_CONFIGURABLE_VBIAS_PIN, \
        (.vbias_pins = DT_PROP_OR(node_id, zephyr_vbias_pins, 0),)) \
}

Get ADC channel configuration from a given devicetree node.

This returns a static initializer for a struct adc_channel_cfg filled with data from a given devicetree node.

Example devicetree fragment:

&adc {
   #address-cells = <1>;
   #size-cells = <0>;
 
   channel@0 {
       reg = <0>;
       zephyr,gain = "ADC_GAIN_1_6";
       zephyr,reference = "ADC_REF_INTERNAL";
       zephyr,acquisition-time = <ADC_ACQ_TIME(ADC_ACQ_TIME_MICROSECONDS, 20)>;
       zephyr,input-positive = <NRF_SAADC_AIN6>;
       zephyr,input-negative = <NRF_SAADC_AIN7>;
   };
 
   channel@1 {
       reg = <1>;
       zephyr,gain = "ADC_GAIN_1_6";
       zephyr,reference = "ADC_REF_INTERNAL";
       zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
       zephyr,input-positive = <NRF_SAADC_AIN0>;
   };
};

Example usage:

static const struct adc_channel_cfg ch0_cfg_dt =
    ADC_CHANNEL_CFG_DT(DT_CHILD(DT_NODELABEL(adc), channel_0));
static const struct adc_channel_cfg ch1_cfg_dt =
    ADC_CHANNEL_CFG_DT(DT_CHILD(DT_NODELABEL(adc), channel_1));
 
// Initializes 'ch0_cfg_dt' to:
// {
//     .channel_id = 0,
//     .gain = ADC_GAIN_1_6,
//     .reference = ADC_REF_INTERNAL,
//     .acquisition_time = ADC_ACQ_TIME(ADC_ACQ_TIME_MICROSECONDS, 20),
//     .differential = true,
//     .input_positive = NRF_SAADC_AIN6,
//     .input-negative = NRF_SAADC_AIN7,
// }
// and 'ch1_cfg_dt' to:
// {
//     .channel_id = 1,
//     .gain = ADC_GAIN_1_6,
//     .reference = ADC_REF_INTERNAL,
//     .acquisition_time = ADC_ACQ_TIME_DEFAULT,
//     .input_positive = NRF_SAADC_AIN0,
// }

Parameters

node_id Devicetree node identifier.

Returns: Static initializer for an adc_channel_cfg structure.

◆ ADC_DT_SPEC_GET

#define ADC_DT_SPEC_GET ( node_id )

#include <zephyr/drivers/adc.h>

Value:

ADC_DT_SPEC_GET_BY_IDX(node_id, 0)

ADC_DT_SPEC_GET_BY_IDX

#define ADC_DT_SPEC_GET_BY_IDX(node_id, idx)

Get ADC io-channel information from devicetree.

Definition adc.h:490

Equivalent to ADC_DT_SPEC_GET_BY_IDX(node_id, 0).

See also: ADC_DT_SPEC_GET_BY_IDX()

Parameters

node_id Devicetree node identifier.

Returns: Static initializer for an adc_dt_spec structure.

◆ ADC_DT_SPEC_GET_BY_IDX

#define ADC_DT_SPEC_GET_BY_IDX	(		node_id,
			idx )

#include <zephyr/drivers/adc.h>

Value:

ADC_DT_SPEC_STRUCT(DT_IO_CHANNELS_CTLR_BY_IDX(node_id, idx), \

DT_IO_CHANNELS_INPUT_BY_IDX(node_id, idx))

DT_IO_CHANNELS_INPUT_BY_IDX

#define DT_IO_CHANNELS_INPUT_BY_IDX(node_id, idx)

Get an io-channels specifier input cell at an index.

Definition io-channels.h:161

DT_IO_CHANNELS_CTLR_BY_IDX

#define DT_IO_CHANNELS_CTLR_BY_IDX(node_id, idx)

Get the node identifier for the node referenced by an io-channels property at an index.

Definition io-channels.h:50

Get ADC io-channel information from devicetree.

This returns a static initializer for an adc_dt_spec structure given a devicetree node and a channel index. The node must have the "io-channels" property defined.

Example devicetree fragment:

/ {
    zephyr,user {
        io-channels = <&adc0 1>, <&adc0 3>;
    };
};
 
&adc0 {
   #address-cells = <1>;
   #size-cells = <0>;
 
   channel@3 {
       reg = <3>;
       zephyr,gain = "ADC_GAIN_1_5";
       zephyr,reference = "ADC_REF_VDD_1_4";
       zephyr,vref-mv = <750>;
       zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
       zephyr,resolution = <12>;
       zephyr,oversampling = <4>;
   };
};

Example usage:

static const struct adc_dt_spec adc_chan0 =
    ADC_DT_SPEC_GET_BY_IDX(DT_PATH(zephyr_user), 0);
static const struct adc_dt_spec adc_chan1 =
    ADC_DT_SPEC_GET_BY_IDX(DT_PATH(zephyr_user), 1);
 
// Initializes 'adc_chan0' to:
// {
//     .dev = DEVICE_DT_GET(DT_NODELABEL(adc0)),
//     .channel_id = 1,
// }
// and 'adc_chan1' to:
// {
//     .dev = DEVICE_DT_GET(DT_NODELABEL(adc0)),
//     .channel_id = 3,
//     .channel_cfg_dt_node_exists = true,
//     .channel_cfg = {
//         .channel_id = 3,
//         .gain = ADC_GAIN_1_5,
//         .reference = ADC_REF_VDD_1_4,
//         .acquisition_time = ADC_ACQ_TIME_DEFAULT,
//     },
//     .vref_mv = 750,
//     .resolution = 12,
//     .oversampling = 4,
// }

See also: ADC_DT_SPEC_GET()

Parameters

node_id	Devicetree node identifier.
idx	Channel index.

Returns: Static initializer for an adc_dt_spec structure.

◆ ADC_DT_SPEC_GET_BY_NAME

#define ADC_DT_SPEC_GET_BY_NAME	(		node_id,
			name )

#include <zephyr/drivers/adc.h>

Value:

ADC_DT_SPEC_STRUCT(DT_IO_CHANNELS_CTLR_BY_NAME(node_id, name), \

DT_IO_CHANNELS_INPUT_BY_NAME(node_id, name))

DT_IO_CHANNELS_CTLR_BY_NAME

#define DT_IO_CHANNELS_CTLR_BY_NAME(node_id, name)

Get the node identifier for the node referenced by an io-channels property by name.

Definition io-channels.h:79

DT_IO_CHANNELS_INPUT_BY_NAME

#define DT_IO_CHANNELS_INPUT_BY_NAME(node_id, name)

Get an io-channels specifier input cell by name.

Definition io-channels.h:203

Get ADC io-channel information from devicetree by name.

This returns a static initializer for an adc_dt_spec structure given a devicetree node and a channel name. The node must have the "io-channels" property defined.

Example devicetree fragment:

/ {
    zephyr,user {
        io-channels = <&adc0 1>, <&adc0 3>;
        io-channel-names = "A0", "A1";
    };
};
 
&adc0 {
   #address-cells = <1>;
   #size-cells = <0>;
 
   channel@3 {
       reg = <3>;
       zephyr,gain = "ADC_GAIN_1_5";
       zephyr,reference = "ADC_REF_VDD_1_4";
       zephyr,vref-mv = <750>;
       zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
       zephyr,resolution = <12>;
       zephyr,oversampling = <4>;
   };
};

Example usage:

static const struct adc_dt_spec adc_chan0 =
    ADC_DT_SPEC_GET_BY_NAME(DT_PATH(zephyr_user), a0);
static const struct adc_dt_spec adc_chan1 =
    ADC_DT_SPEC_GET_BY_NAME(DT_PATH(zephyr_user), a1);
 
// Initializes 'adc_chan0' to:
// {
//     .dev = DEVICE_DT_GET(DT_NODELABEL(adc0)),
//     .channel_id = 1,
// }
// and 'adc_chan1' to:
// {
//     .dev = DEVICE_DT_GET(DT_NODELABEL(adc0)),
//     .channel_id = 3,
//     .channel_cfg_dt_node_exists = true,
//     .channel_cfg = {
//         .channel_id = 3,
//         .gain = ADC_GAIN_1_5,
//         .reference = ADC_REF_VDD_1_4,
//         .acquisition_time = ADC_ACQ_TIME_DEFAULT,
//     },
//     .vref_mv = 750,
//     .resolution = 12,
//     .oversampling = 4,
// }

Parameters

node_id	Devicetree node identifier.
name	Channel name.

Returns: Static initializer for an adc_dt_spec structure.

◆ ADC_DT_SPEC_INST_GET

#define ADC_DT_SPEC_INST_GET ( inst )

#include <zephyr/drivers/adc.h>

Value:

ADC_DT_SPEC_GET(DT_DRV_INST(inst))

ADC_DT_SPEC_GET

#define ADC_DT_SPEC_GET(node_id)

Equivalent to ADC_DT_SPEC_GET_BY_IDX(node_id, 0).

Definition adc.h:516

DT_DRV_INST

#define DT_DRV_INST(inst)

Node identifier for an instance of a DT_DRV_COMPAT compatible.

Definition devicetree.h:3645

Equivalent to ADC_DT_SPEC_INST_GET_BY_IDX(inst, 0).

See also: ADC_DT_SPEC_GET()

Parameters

inst	DT_DRV_COMPAT instance number

Returns: Static initializer for an adc_dt_spec structure.

◆ ADC_DT_SPEC_INST_GET_BY_IDX

#define ADC_DT_SPEC_INST_GET_BY_IDX	(		inst,
			idx )

#include <zephyr/drivers/adc.h>

Value:

ADC_DT_SPEC_GET_BY_IDX(DT_DRV_INST(inst), idx)

Get ADC io-channel information from a DT_DRV_COMPAT devicetree instance.

See also: ADC_DT_SPEC_GET_BY_IDX()

Parameters

inst	DT_DRV_COMPAT instance number
idx	Channel index.

Returns: Static initializer for an adc_dt_spec structure.

◆ ADC_DT_SPEC_INST_GET_BY_NAME

#define ADC_DT_SPEC_INST_GET_BY_NAME	(		inst,
			name )

#include <zephyr/drivers/adc.h>

Value:

ADC_DT_SPEC_GET_BY_NAME(DT_DRV_INST(inst), name)

Get ADC io-channel information from a DT_DRV_COMPAT devicetree instance by name.

See also: ADC_DT_SPEC_GET_BY_NAME()

Parameters

inst	DT_DRV_COMPAT instance number
name	Channel name.

Returns: Static initializer for an adc_dt_spec structure.

Typedef Documentation

◆ adc_api_channel_setup

typedef int(* adc_api_channel_setup) (const struct device *dev, const struct adc_channel_cfg *channel_cfg)

#include <zephyr/drivers/adc.h>

Type definition of ADC API function for configuring a channel.

See adc_channel_setup() for argument descriptions.

◆ adc_api_read

typedef int(* adc_api_read) (const struct device *dev, const struct adc_sequence *sequence)

#include <zephyr/drivers/adc.h>

Type definition of ADC API function for setting a read request.

See adc_read() for argument descriptions.

◆ adc_api_read_async

typedef int(* adc_api_read_async) (const struct device *dev, const struct adc_sequence *sequence, struct k_poll_signal *async)

#include <zephyr/drivers/adc.h>

Type definition of ADC API function for setting an asynchronous read request.

See adc_read_async() for argument descriptions.

◆ adc_sequence_callback

typedef enum adc_action(* adc_sequence_callback) (const struct device *dev, const struct adc_sequence *sequence, uint16_t sampling_index)

#include <zephyr/drivers/adc.h>

Type definition of the optional callback function to be called after a requested sampling is done.

Parameters

dev	Pointer to the device structure for the driver instance.
sequence	Pointer to the sequence structure that triggered the sampling. This parameter points to a copy of the structure that was supplied to the call that started the sampling sequence, thus it cannot be used with the CONTAINER_OF() macro to retrieve some other data associated with the sequence. Instead, the adc_sequence_options::user_data field should be used for such purpose.
sampling_index	Index (0-65535) of the sampling done.

Returns: Action to be performed by the driver. See adc_action.

Enumeration Type Documentation

◆ adc_action

enum adc_action

#include <zephyr/drivers/adc.h>

Action to be performed after a sampling is done.

Enumerator

ADC_ACTION_CONTINUE

The sequence should be continued normally.

ADC_ACTION_REPEAT

The sampling should be repeated.

New samples or sample should be read from the ADC and written in the same place as the recent ones.

ADC_ACTION_FINISH

The sequence should be finished immediately.

◆ adc_gain

enum adc_gain

#include <zephyr/drivers/adc.h>

ADC channel gain factors.

Enumerator
ADC_GAIN_1_6	x 1/6.
ADC_GAIN_1_5	x 1/5.
ADC_GAIN_1_4	x 1/4.
ADC_GAIN_1_3	x 1/3.
ADC_GAIN_2_5	x 2/5.
ADC_GAIN_1_2	x 1/2.
ADC_GAIN_2_3	x 2/3.
ADC_GAIN_4_5	x 4/5.
ADC_GAIN_1	x 1.
ADC_GAIN_2	x 2.
ADC_GAIN_3	x 3.
ADC_GAIN_4	x 4.
ADC_GAIN_6	x 6.
ADC_GAIN_8	x 8.
ADC_GAIN_12	x 12.
ADC_GAIN_16	x 16.
ADC_GAIN_24	x 24.
ADC_GAIN_32	x 32.
ADC_GAIN_64	x 64.
ADC_GAIN_128	x 128.

◆ adc_reference

enum adc_reference

#include <zephyr/drivers/adc.h>

ADC references.

Enumerator
ADC_REF_VDD_1	VDD.
ADC_REF_VDD_1_2	VDD/2.
ADC_REF_VDD_1_3	VDD/3.
ADC_REF_VDD_1_4	VDD/4.
ADC_REF_INTERNAL	Internal.
ADC_REF_EXTERNAL0	External, input 0.
ADC_REF_EXTERNAL1	External, input 1.

Function Documentation

◆ adc_channel_setup()

int adc_channel_setup	(	const struct device *	dev,
		const struct adc_channel_cfg *	channel_cfg )

#include <zephyr/drivers/adc.h>

Configure an ADC channel.

It is required to call this function and configure each channel before it is selected for a read request.

Parameters

dev	Pointer to the device structure for the driver instance.
channel_cfg	Channel configuration.

Return values

0	On success.
-EINVAL	If a parameter with an invalid value has been provided.

◆ adc_channel_setup_dt()

static int adc_channel_setup_dt ( const struct adc_dt_spec * spec )

inlinestatic

#include <zephyr/drivers/adc.h>

Configure an ADC channel from a struct adc_dt_spec.

Parameters

spec	ADC specification from Devicetree.

Returns: A value from adc_channel_setup() or -ENOTSUP if information from Devicetree is not valid.

See also: adc_channel_setup()

◆ adc_gain_invert()

int adc_gain_invert	(	enum adc_gain	gain,
		int32_t *	value )

#include <zephyr/drivers/adc.h>

Invert the application of gain to a measurement value.

For example, if the gain passed in is ADC_GAIN_1_6 and the referenced value is 10, the value after the function returns is 60.

Parameters

gain	the gain used to amplify the input signal.
value	a pointer to a value that initially has the effect of the applied gain but has that effect removed when this function successfully returns. If the gain cannot be reversed the value remains unchanged.

Return values

0	if the gain was successfully reversed
-EINVAL	if the gain could not be interpreted

◆ adc_is_ready_dt()

static bool adc_is_ready_dt ( const struct adc_dt_spec * spec )

inlinestatic

#include <zephyr/drivers/adc.h>

Validate that the ADC device is ready.

Parameters

spec	ADC specification from devicetree

Return values

true	if the ADC device is ready for use and false otherwise.

◆ adc_raw_to_millivolts()

static int adc_raw_to_millivolts	(	int32_t	ref_mv,
		enum adc_gain	gain,
		uint8_t	resolution,
		int32_t *	valp )

inlinestatic

#include <zephyr/drivers/adc.h>

Convert a raw ADC value to millivolts.

This function performs the necessary conversion to transform a raw ADC measurement to a voltage in millivolts.

Parameters

ref_mv	the reference voltage used for the measurement, in millivolts. This may be from adc_ref_internal() or a known external reference.
gain	the ADC gain configuration used to sample the input
resolution	the number of bits in the absolute value of the sample. For differential sampling this needs to be one less than the resolution in struct adc_sequence.
valp	pointer to the raw measurement value on input, and the corresponding millivolt value on successful conversion. If conversion fails the stored value is left unchanged.

Return values

0	on successful conversion
-EINVAL	if the gain is not reversible

◆ adc_raw_to_millivolts_dt()

static int adc_raw_to_millivolts_dt	(	const struct adc_dt_spec *	spec,
		int32_t *	valp )

inlinestatic

#include <zephyr/drivers/adc.h>

Convert a raw ADC value to millivolts using information stored in a struct adc_dt_spec.

Parameters

[in]	spec	ADC specification from Devicetree.
[in,out]	valp	Pointer to the raw measurement value on input, and the corresponding millivolt value on successful conversion. If conversion fails the stored value is left unchanged.

Returns: A value from adc_raw_to_millivolts() or -ENOTSUP if information from Devicetree is not valid.

See also: adc_raw_to_millivolts()

◆ adc_read()

int adc_read	(	const struct device *	dev,
		const struct adc_sequence *	sequence )

#include <zephyr/drivers/adc.h>

Set a read request.

Parameters

dev	Pointer to the device structure for the driver instance.
sequence	Structure specifying requested sequence of samplings.

If invoked from user mode, any sequence struct options for callback must be NULL.

Return values

0	On success.
-EINVAL	If a parameter with an invalid value has been provided.
-ENOMEM	If the provided buffer is to small to hold the results of all requested samplings.
-ENOTSUP	If the requested mode of operation is not supported.
-EBUSY	If another sampling was triggered while the previous one was still in progress. This may occur only when samplings are done with intervals, and it indicates that the selected interval was too small. All requested samples are written in the buffer, but at least some of them were taken with an extra delay compared to what was scheduled.

◆ adc_read_async()

int adc_read_async	(	const struct device *	dev,
		const struct adc_sequence *	sequence,
		struct k_poll_signal *	async )

#include <zephyr/drivers/adc.h>

Set an asynchronous read request.

Note

This function is available only if

CONFIG_ADC_ASYNC

is selected.

If invoked from user mode, any sequence struct options for callback must be NULL.

Parameters

dev	Pointer to the device structure for the driver instance.
sequence	Structure specifying requested sequence of samplings.
async	Pointer to a valid and ready to be signaled struct k_poll_signal. (Note: if NULL this function will not notify the end of the transaction, and whether it went successfully or not).

Returns: 0 on success, negative error code otherwise. See adc_read() for a list of possible error codes.

◆ adc_read_dt()

static int adc_read_dt	(	const struct adc_dt_spec *	spec,
		const struct adc_sequence *	sequence )

inlinestatic

#include <zephyr/drivers/adc.h>

Set a read request from a struct adc_dt_spec.

Parameters

spec	ADC specification from Devicetree.
sequence	Structure specifying requested sequence of samplings.

Returns: A value from adc_read().

See also: adc_read()

◆ adc_ref_internal()

static uint16_t adc_ref_internal ( const struct device * dev )

inlinestatic

#include <zephyr/drivers/adc.h>

Get the internal reference voltage.

Returns the voltage corresponding to ADC_REF_INTERNAL, measured in millivolts.

Returns: a positive value is the reference voltage value. Returns zero if reference voltage information is not available.

◆ adc_sequence_init_dt()

static int adc_sequence_init_dt	(	const struct adc_dt_spec *	spec,
		struct adc_sequence *	seq )

inlinestatic

#include <zephyr/drivers/adc.h>

Initialize a struct adc_sequence from information stored in struct adc_dt_spec.

Note that this function only initializes the following fields:

Other fields should be initialized by the caller.

Parameters

[in]	spec	ADC specification from Devicetree.
[out]	seq	Sequence to initialize.

Return values

0	On success
-ENOTSUP	If `spec` does not have valid channel configuration

Topics

Data Structures

Macros

Typedefs

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ ADC_CHANNEL_CFG_DT

◆ ADC_DT_SPEC_GET

◆ ADC_DT_SPEC_GET_BY_IDX

◆ ADC_DT_SPEC_GET_BY_NAME

◆ ADC_DT_SPEC_INST_GET

◆ ADC_DT_SPEC_INST_GET_BY_IDX

◆ ADC_DT_SPEC_INST_GET_BY_NAME

Typedef Documentation

◆ adc_api_channel_setup

◆ adc_api_read

◆ adc_api_read_async

◆ adc_sequence_callback

Enumeration Type Documentation

◆ adc_action

◆ adc_gain

◆ adc_reference

Function Documentation

◆ adc_channel_setup()

◆ adc_channel_setup_dt()

◆ adc_gain_invert()

◆ adc_is_ready_dt()

◆ adc_raw_to_millivolts()

◆ adc_raw_to_millivolts_dt()

◆ adc_read()

◆ adc_read_async()

◆ adc_read_dt()

◆ adc_ref_internal()

◆ adc_sequence_init_dt()