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adc.h
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1
6/*
7 * Copyright (c) 2018 Nordic Semiconductor ASA
8 * Copyright (c) 2015 Intel Corporation
9 *
10 * SPDX-License-Identifier: Apache-2.0
11 */
12
13#ifndef ZEPHYR_INCLUDE_DRIVERS_ADC_H_
14#define ZEPHYR_INCLUDE_DRIVERS_ADC_H_
15
16#include <zephyr/device.h>
18#include <zephyr/kernel.h>
19
20#ifdef __cplusplus
21extern "C" {
22#endif
23
57
74int adc_gain_invert(enum adc_gain gain, int32_t *value);
75
92int adc_gain_invert_64(enum adc_gain gain, int64_t *value);
93
104
111
114
125
149
152
153#ifdef CONFIG_ADC_CONFIGURABLE_INPUTS
159 uint8_t input_positive;
160
166 uint8_t input_negative;
167#endif /* CONFIG_ADC_CONFIGURABLE_INPUTS */
168
169#ifdef CONFIG_ADC_CONFIGURABLE_EXCITATION_CURRENT_SOURCE_PIN
170 uint8_t current_source_pin_set : 1;
177 uint8_t current_source_pin[2];
178#endif /* CONFIG_ADC_CONFIGURABLE_EXCITATION_CURRENT_SOURCE_PIN */
179
180#ifdef CONFIG_ADC_CONFIGURABLE_VBIAS_PIN
189 uint32_t vbias_pins;
190#endif /* CONFIG_ADC_CONFIGURABLE_VBIAS_PIN */
191};
192
257#define ADC_CHANNEL_CFG_DT(node_id) { \
258 .gain = DT_STRING_TOKEN(node_id, zephyr_gain), \
259 .reference = DT_STRING_TOKEN(node_id, zephyr_reference), \
260 .acquisition_time = DT_PROP(node_id, zephyr_acquisition_time), \
261 .channel_id = DT_REG_ADDR(node_id), \
262IF_ENABLED(UTIL_OR(DT_PROP(node_id, zephyr_differential), \
263 UTIL_AND(CONFIG_ADC_CONFIGURABLE_INPUTS, \
264 DT_NODE_HAS_PROP(node_id, zephyr_input_negative))), \
265 (.differential = true,)) \
266IF_ENABLED(CONFIG_ADC_CONFIGURABLE_INPUTS, \
267 (.input_positive = DT_PROP_OR(node_id, zephyr_input_positive, 0), \
268 .input_negative = DT_PROP_OR(node_id, zephyr_input_negative, 0),)) \
269IF_ENABLED(CONFIG_ADC_CONFIGURABLE_EXCITATION_CURRENT_SOURCE_PIN, \
270 (.current_source_pin_set = DT_NODE_HAS_PROP(node_id, zephyr_current_source_pin), \
271 .current_source_pin = DT_PROP_OR(node_id, zephyr_current_source_pin, {0}),)) \
272IF_ENABLED(CONFIG_ADC_CONFIGURABLE_VBIAS_PIN, \
273 (.vbias_pins = DT_PROP_OR(node_id, zephyr_vbias_pins, 0),)) \
274}
275
328
331#define ADC_DT_SPEC_STRUCT(ctlr, input) { \
332 .dev = DEVICE_DT_GET(ctlr), \
333 .channel_id = input, \
334 ADC_CHANNEL_CFG_FROM_DT_NODE(\
335 ADC_CHANNEL_DT_NODE(ctlr, input)) \
336 }
337
338#define ADC_CHANNEL_DT_NODE(ctlr, input) \
339 DT_FOREACH_CHILD_VARGS(ctlr, ADC_FOREACH_INPUT, input)
340
341#define ADC_FOREACH_INPUT(node, input) \
342 IF_ENABLED(IS_EQ(DT_REG_ADDR_RAW(node), input), (node))
343
344#define ADC_CHANNEL_CFG_FROM_DT_NODE(node_id) \
345 IF_ENABLED(DT_NODE_EXISTS(node_id), \
346 (.channel_cfg_dt_node_exists = true, \
347 .channel_cfg = ADC_CHANNEL_CFG_DT(node_id), \
348 .vref_mv = DT_PROP_OR(node_id, zephyr_vref_mv, 0), \
349 .resolution = DT_PROP_OR(node_id, zephyr_resolution, 0), \
350 .oversampling = DT_PROP_OR(node_id, zephyr_oversampling, 0),))
351
422#define ADC_DT_SPEC_GET_BY_NAME(node_id, name) \
423 ADC_DT_SPEC_STRUCT(DT_IO_CHANNELS_CTLR_BY_NAME(node_id, name), \
424 DT_IO_CHANNELS_INPUT_BY_NAME(node_id, name))
425
436#define ADC_DT_SPEC_INST_GET_BY_NAME(inst, name) \
437 ADC_DT_SPEC_GET_BY_NAME(DT_DRV_INST(inst), name)
438
508#define ADC_DT_SPEC_GET_BY_IDX(node_id, idx) \
509 ADC_DT_SPEC_STRUCT(DT_IO_CHANNELS_CTLR_BY_IDX(node_id, idx), \
510 DT_IO_CHANNELS_INPUT_BY_IDX(node_id, idx))
511
522#define ADC_DT_SPEC_INST_GET_BY_IDX(inst, idx) \
523 ADC_DT_SPEC_GET_BY_IDX(DT_DRV_INST(inst), idx)
524
534#define ADC_DT_SPEC_GET(node_id) ADC_DT_SPEC_GET_BY_IDX(node_id, 0)
535
544#define ADC_DT_SPEC_INST_GET(inst) ADC_DT_SPEC_GET(DT_DRV_INST(inst))
545
546/* Forward declaration of the adc_sequence structure. */
547struct adc_sequence;
548
565
585typedef enum adc_action (*adc_sequence_callback)(const struct device *dev,
586 const struct adc_sequence *sequence,
587 uint16_t sampling_index);
588
622
690
691
696typedef int (*adc_api_channel_setup)(const struct device *dev,
697 const struct adc_channel_cfg *channel_cfg);
698
703typedef int (*adc_api_read)(const struct device *dev,
704 const struct adc_sequence *sequence);
705
711typedef int (*adc_api_read_async)(const struct device *dev,
712 const struct adc_sequence *sequence,
713 struct k_poll_signal *async);
714
720__subsystem struct adc_driver_api {
723#ifdef CONFIG_ADC_ASYNC
724 adc_api_read_async read_async;
725#endif
727};
728
741__syscall int adc_channel_setup(const struct device *dev,
742 const struct adc_channel_cfg *channel_cfg);
743
744static inline int z_impl_adc_channel_setup(const struct device *dev,
745 const struct adc_channel_cfg *channel_cfg)
746{
747 return DEVICE_API_GET(adc, dev)->channel_setup(dev, channel_cfg);
748}
749
759static inline int adc_channel_setup_dt(const struct adc_dt_spec *spec)
760{
761 if (!spec->channel_cfg_dt_node_exists) {
762 return -ENOTSUP;
763 }
764
765 return adc_channel_setup(spec->dev, &spec->channel_cfg);
766}
767
789__syscall int adc_read(const struct device *dev,
790 const struct adc_sequence *sequence);
791
792static inline int z_impl_adc_read(const struct device *dev,
793 const struct adc_sequence *sequence)
794{
795 return DEVICE_API_GET(adc, dev)->read(dev, sequence);
796}
797
807static inline int adc_read_dt(const struct adc_dt_spec *spec,
808 const struct adc_sequence *sequence)
809{
810 return adc_read(spec->dev, sequence);
811}
812
833__syscall int adc_read_async(const struct device *dev,
834 const struct adc_sequence *sequence,
835 struct k_poll_signal *async);
836
837
838#ifdef CONFIG_ADC_ASYNC
839static inline int z_impl_adc_read_async(const struct device *dev,
840 const struct adc_sequence *sequence,
841 struct k_poll_signal *async)
842{
843 return DEVICE_API_GET(adc, dev)->read_async(dev, sequence, async);
844}
845#endif /* CONFIG_ADC_ASYNC */
846
856static inline uint16_t adc_ref_internal(const struct device *dev)
857{
858 return DEVICE_API_GET(adc, dev)->ref_internal;
859}
860
884typedef int (*adc_raw_to_x_fn)(int32_t ref_mv, enum adc_gain gain, uint8_t resolution,
885 int32_t *valp);
886
892static inline int adc_raw_to_millivolts(int32_t ref_mv, enum adc_gain gain, uint8_t resolution,
893 int32_t *valp)
894{
895 int32_t adc_mv = *valp * ref_mv;
896 int ret = adc_gain_invert(gain, &adc_mv);
897
898 if (ret == 0) {
899 *valp = (adc_mv >> resolution);
900 }
901
902 return ret;
903}
904
910static inline int adc_raw_to_microvolts(int32_t ref_mv, enum adc_gain gain, uint8_t resolution,
911 int32_t *valp)
912{
913 int64_t adc_uv = (int64_t)*valp * ref_mv * 1000;
914 int ret = adc_gain_invert_64(gain, &adc_uv);
915
916 if (ret == 0) {
917 *valp = (int32_t)(adc_uv >> resolution);
918 }
919
920 return ret;
921}
922
939static inline int adc_raw_to_x_dt_chan(adc_raw_to_x_fn conv_func,
940 const struct adc_dt_spec *spec,
941 const struct adc_channel_cfg *channel_cfg,
942 int32_t *valp)
943{
944 int32_t vref_mv;
945 uint8_t resolution;
946
947 if (!spec->channel_cfg_dt_node_exists) {
948 return -ENOTSUP;
949 }
950
951 if (channel_cfg->reference == ADC_REF_INTERNAL) {
952 vref_mv = (int32_t)adc_ref_internal(spec->dev);
953 } else {
954 vref_mv = spec->vref_mv;
955 }
956
957 resolution = spec->resolution;
958
959 /*
960 * For differential channels, one bit less needs to be specified
961 * for resolution to achieve correct conversion.
962 */
963 if (channel_cfg->differential) {
964 resolution -= 1U;
965 }
966
967 return conv_func(vref_mv, channel_cfg->gain, resolution, valp);
968}
969
970
984static inline int adc_raw_to_millivolts_dt(const struct adc_dt_spec *spec, int32_t *valp)
985{
986 return adc_raw_to_x_dt_chan(adc_raw_to_millivolts, spec, &spec->channel_cfg, valp);
987}
988
1002static inline int adc_raw_to_microvolts_dt(const struct adc_dt_spec *spec, int32_t *valp)
1003{
1004 return adc_raw_to_x_dt_chan(adc_raw_to_microvolts, spec, &spec->channel_cfg, valp);
1005}
1006
1025static inline int adc_sequence_init_dt(const struct adc_dt_spec *spec,
1026 struct adc_sequence *seq)
1027{
1028 if (!spec->channel_cfg_dt_node_exists) {
1029 return -ENOTSUP;
1030 }
1031
1032 seq->channels = BIT(spec->channel_id);
1033 seq->resolution = spec->resolution;
1034 seq->oversampling = spec->oversampling;
1035
1036 return 0;
1037}
1038
1046static inline bool adc_is_ready_dt(const struct adc_dt_spec *spec)
1047{
1048 return device_is_ready(spec->dev);
1049}
1050
1055#ifdef __cplusplus
1056}
1057#endif
1058
1059#include <zephyr/syscalls/adc.h>
1060
1061#endif /* ZEPHYR_INCLUDE_DRIVERS_ADC_H_ */
#define DEVICE_API_GET(_class, _dev)
Expands to the pointer of a device's API for a given class.
Definition device.h:1350
int adc_read_async(const struct device *dev, const struct adc_sequence *sequence, struct k_poll_signal *async)
Set an asynchronous read request.
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.
Definition adc.h:984
static int adc_raw_to_x_dt_chan(adc_raw_to_x_fn conv_func, const struct adc_dt_spec *spec, const struct adc_channel_cfg *channel_cfg, int32_t *valp)
Convert a raw ADC value to an arbitrary output unit.
Definition adc.h:939
int adc_gain_invert_64(enum adc_gain gain, int64_t *value)
Invert the application of gain to a measurement value.
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.
Definition adc.h:807
adc_gain
ADC channel gain factors.
Definition adc.h:34
static bool adc_is_ready_dt(const struct adc_dt_spec *spec)
Validate that the ADC device is ready.
Definition adc.h:1046
int(* adc_raw_to_x_fn)(int32_t ref_mv, enum adc_gain gain, uint8_t resolution, int32_t *valp)
Conversion from raw ADC units to a specific output unit.
Definition adc.h:884
static int adc_raw_to_microvolts(int32_t ref_mv, enum adc_gain gain, uint8_t resolution, int32_t *valp)
Convert a raw ADC value to microvolts.
Definition adc.h:910
static int adc_raw_to_microvolts_dt(const struct adc_dt_spec *spec, int32_t *valp)
Convert a raw ADC value to microvolts using information stored in a struct adc_dt_spec.
Definition adc.h:1002
int(* adc_api_read)(const struct device *dev, const struct adc_sequence *sequence)
Type definition of ADC API function for setting a read request.
Definition adc.h:703
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.
Definition adc.h:1025
int adc_gain_invert(enum adc_gain gain, int32_t *value)
Invert the application of gain to a measurement value.
int adc_read(const struct device *dev, const struct adc_sequence *sequence)
Set a read request.
int adc_channel_setup(const struct device *dev, const struct adc_channel_cfg *channel_cfg)
Configure an ADC channel.
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.
Definition adc.h:696
adc_action
Action to be performed after a sampling is done.
Definition adc.h:552
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.
Definition adc.h:585
adc_reference
ADC references.
Definition adc.h:95
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.
Definition adc.h:711
static uint16_t adc_ref_internal(const struct device *dev)
Get the internal reference voltage.
Definition adc.h:856
static int adc_channel_setup_dt(const struct adc_dt_spec *spec)
Configure an ADC channel from a struct adc_dt_spec.
Definition adc.h:759
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.
Definition adc.h:892
@ ADC_GAIN_64
x 64.
Definition adc.h:54
@ ADC_GAIN_3
x 3.
Definition adc.h:46
@ ADC_GAIN_4
x 4.
Definition adc.h:47
@ ADC_GAIN_1_5
x 1/5.
Definition adc.h:36
@ ADC_GAIN_128
x 128.
Definition adc.h:55
@ ADC_GAIN_1_2
x 1/2.
Definition adc.h:41
@ ADC_GAIN_2_7
x 2/7.
Definition adc.h:38
@ ADC_GAIN_12
x 12.
Definition adc.h:50
@ ADC_GAIN_2_5
x 2/5.
Definition adc.h:40
@ ADC_GAIN_16
x 16.
Definition adc.h:51
@ ADC_GAIN_24
x 24.
Definition adc.h:52
@ ADC_GAIN_1
x 1.
Definition adc.h:44
@ ADC_GAIN_6
x 6.
Definition adc.h:48
@ ADC_GAIN_1_6
x 1/6.
Definition adc.h:35
@ ADC_GAIN_32
x 32.
Definition adc.h:53
@ ADC_GAIN_2_3
x 2/3.
Definition adc.h:42
@ ADC_GAIN_4_5
x 4/5.
Definition adc.h:43
@ ADC_GAIN_8
x 8.
Definition adc.h:49
@ ADC_GAIN_1_3
x 1/3.
Definition adc.h:39
@ ADC_GAIN_1_4
x 1/4.
Definition adc.h:37
@ ADC_GAIN_2
x 2.
Definition adc.h:45
@ ADC_ACTION_FINISH
The sequence should be finished immediately.
Definition adc.h:563
@ ADC_ACTION_REPEAT
The sampling should be repeated.
Definition adc.h:560
@ ADC_ACTION_CONTINUE
The sequence should be continued normally.
Definition adc.h:554
@ ADC_REF_INTERNAL
Internal.
Definition adc.h:100
@ ADC_REF_EXTERNAL1
External, input 1.
Definition adc.h:102
@ ADC_REF_VDD_1_2
VDD/2.
Definition adc.h:97
@ ADC_REF_VDD_1_3
VDD/3.
Definition adc.h:98
@ ADC_REF_VDD_1_4
VDD/4.
Definition adc.h:99
@ ADC_REF_VDD_1
VDD.
Definition adc.h:96
@ ADC_REF_EXTERNAL0
External, input 0.
Definition adc.h:101
bool device_is_ready(const struct device *dev)
Verify that a device is ready for use.
#define BIT(n)
Unsigned integer with bit position n set (signed in assembly language).
Definition util_macro.h:44
#define ENOTSUP
Unsupported value.
Definition errno.h:114
Public kernel APIs.
__UINT32_TYPE__ uint32_t
Definition stdint.h:90
__INT32_TYPE__ int32_t
Definition stdint.h:74
__UINT8_TYPE__ uint8_t
Definition stdint.h:88
__UINT16_TYPE__ uint16_t
Definition stdint.h:89
__INT64_TYPE__ int64_t
Definition stdint.h:75
Structure for specifying the configuration of an ADC channel.
Definition adc.h:108
enum adc_gain gain
Gain selection.
Definition adc.h:110
uint8_t differential
Channel type: single-ended or differential.
Definition adc.h:151
uint16_t acquisition_time
Acquisition time.
Definition adc.h:124
enum adc_reference reference
Reference selection.
Definition adc.h:113
uint8_t channel_id
Channel identifier.
Definition adc.h:148
ADC driver API.
Definition adc.h:720
adc_api_read read
Definition adc.h:722
uint16_t ref_internal
Definition adc.h:726
adc_api_channel_setup channel_setup
Definition adc.h:721
Container for ADC channel information specified in devicetree.
Definition adc.h:282
struct adc_channel_cfg channel_cfg
Configuration of the associated ADC channel specified in devicetree.
Definition adc.h:304
uint8_t channel_id
ADC channel identifier used by this io-channel.
Definition adc.h:290
uint16_t vref_mv
Voltage of the reference selected for the channel or 0 if this value is not provided in devicetree.
Definition adc.h:312
const struct device * dev
Pointer to the device structure for the ADC driver instance used by this io-channel.
Definition adc.h:287
uint8_t oversampling
Oversampling setting to be used for that channel.
Definition adc.h:326
bool channel_cfg_dt_node_exists
Flag indicating whether configuration of the associated ADC channel is provided as a child node of th...
Definition adc.h:297
uint8_t resolution
ADC resolution to be used for that channel.
Definition adc.h:319
Structure defining additional options for an ADC sampling sequence.
Definition adc.h:592
void * user_data
Pointer to user data.
Definition adc.h:614
uint16_t extra_samplings
Number of extra samplings to perform (the total number of samplings is 1 + extra_samplings).
Definition adc.h:620
adc_sequence_callback callback
Callback function to be called after each sampling is done.
Definition adc.h:608
uint32_t interval_us
Interval between consecutive samplings (in microseconds), 0 means sample as fast as possible,...
Definition adc.h:602
Structure defining an ADC sampling sequence.
Definition adc.h:626
uint8_t oversampling
Oversampling setting.
Definition adc.h:678
const struct adc_sequence_options * options
Pointer to a structure defining additional options for the sequence.
Definition adc.h:631
uint32_t channels
Bit-mask indicating the channels to be included in each sampling of this sequence.
Definition adc.h:640
void * buffer
Pointer to a buffer where the samples are to be written.
Definition adc.h:653
bool calibrate
Perform calibration before the reading is taken if requested.
Definition adc.h:688
size_t buffer_size
Specifies the actual size of the buffer pointed by the "buffer" field (in bytes).
Definition adc.h:661
uint8_t resolution
ADC resolution.
Definition adc.h:670
Runtime device structure (in ROM) per driver instance.
Definition device.h:510
Definition kernel.h:6068