dey-examples: add adc_sample application for ccimx6ul

https://jira.digi.com/browse/DEL-3218

Signed-off-by: Pedro Perez de Heredia <pedro.perez@digi.com>

meta-digi-dey/recipes-digi/dey-examples/dey-examples-adc.bb

@@ -0,0 +1,16 @@
+SUMMARY = "DEY examples: ADC test application"
+SECTION = "examples"
+LICENSE = "GPL-2.0"
+LIC_FILES_CHKSUM = "file://${COMMON_LICENSE_DIR}/GPL-2.0;md5=801f80980d171dd6425610833a22dbe6"
+
+SRC_URI = "file://adc_sample"
+
+S = "${WORKDIR}/adc_sample"
+
+do_install() {
+	install -d ${D}${bindir}
+	install -m 0755 adc_sample ${D}${bindir}
+}
+
+PACKAGE_ARCH = "${MACHINE_ARCH}"
+COMPATIBLE_MACHINE = "(ccimx6ul)"

meta-digi-dey/recipes-digi/dey-examples/files/adc_sample/Makefile

@@ -0,0 +1,11 @@
+CFLAGS = -Wall -g -D_GNU_SOURCE
+
+all: adc_sample
+
+adc_sample: adc_sample.o iio_utils.o
+
+%.o: %.c iio_utils.h
+
+.PHONY: clean
+clean:
+	rm -f *.o adc_sample

meta-digi-dey/recipes-digi/dey-examples/files/adc_sample/adc_sample.c

@@ -0,0 +1,337 @@
+/*
+ * ConnectCore 6UL ADC sample application.
+ *
+ * Copyright (c) 2016 Digi International Inc.
+ * All rights reserved.
+ *
+ * Partially based on iio_event_monitor.c from the tools/iio directory, of the
+ * linux kernel.
+ *
+ * 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.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <poll.h>
+#include <sys/ioctl.h>
+
+#include "iio_utils.h"
+
+#define ARRAY_SIZE(v)		(sizeof(v) / sizeof((v)[0]))
+#define BUFFER_LEN		20
+
+#define ADC_SAMPLE_USAGE						\
+	"Usage:\n"							\
+	"adc_sample -t ADC_type -c channel [options]\n\n"
+
+#define ADC_SAMPLE_FULL_USAGE						\
+	"Usage:\n"							\
+	"adc_sample -t ADC_type -c channel [options]\n\n"		\
+	"Options:\n"							\
+	"  -t : ADC_type ('MX6UL', 'MCA')\n"				\
+	"  -c : channel number to read from\n"				\
+	"  -n : Number of samples (default: 1)\n"			\
+	"  -d : Delay (in ms) between samples (default: 1000)\n"	\
+	"  -v : Show output in V (otherwise raw ADC value is shown)\n"	\
+	"  -h : help\n\n"
+
+enum adc_type {
+	ADC_TYPE_UNKNOWN,
+	ADC_TYPE_MX6UL,
+	ADC_TYPE_MCA
+};
+
+struct adc_data {
+	enum adc_type type;
+	const char *name;
+	const char *dev_name;
+	unsigned int nbits;
+};
+
+struct adc_data adc_list[] = {
+	{
+		.type 		= ADC_TYPE_MX6UL,
+		.name 		= "MX6UL",
+		.dev_name 	= "2198000.adc",
+		.nbits 		= 12,
+	}, {
+		.type 		= ADC_TYPE_MCA,
+		.name 		= "MCA",
+		.dev_name 	= "mca-cc6ul-adc",
+		.nbits 		= 12,
+	}
+};
+
+typedef struct adc {
+	struct adc_data *data;
+	char *chrdev_name;
+	char *sysfs_file;
+	char *sysfs_dir;
+	int dev_num;
+	unsigned long channel;
+	double voltage_scale;
+} adc_t;
+
+static void show_usage(int full)
+{
+	fprintf(stdout, "%s", full ?
+		ADC_SAMPLE_FULL_USAGE : ADC_SAMPLE_USAGE);
+}
+
+static struct adc_data *get_adc_data(const char *type_str)
+{
+	struct adc_data *data = NULL;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(adc_list); i++) {
+		if (!strcmp(adc_list[i].name, type_str)) {
+			data = &adc_list[i];
+			break;
+		}
+	}
+
+	return data;
+}
+
+static int read_adc_sample_sysfs(adc_t *adc, long int *val)
+{
+	int fd, ret;
+	char buffer[BUFFER_LEN];
+
+	fd = open(adc->sysfs_file, O_RDONLY);
+	if (fd < 0) {
+		fprintf(stdout, "%s: failed to open %s\n",
+			__func__, adc->sysfs_file);
+		ret = fd;
+		goto just_ret;
+	}
+
+	ret = read(fd, buffer, BUFFER_LEN);
+	if (ret < 0) {
+		fprintf(stdout, "%s: failed to read ADC sample from %s (%d)\n",
+			__func__, adc->sysfs_file, ret);
+		goto close_ret;
+	}
+
+	if (ret == 0) {
+		fprintf(stdout, "%s: no data available in %s\n",
+			__func__, adc->sysfs_file);
+		ret = -ENODATA;
+		goto close_ret;
+	}
+
+	*val = strtol(buffer, NULL, 10);
+	ret = 0;
+
+close_ret:
+	close(fd);
+just_ret:
+	return ret;
+}
+
+static int read_voltage_scale(adc_t *adc, double *val)
+{
+	int fd, ret;
+	char buffer[BUFFER_LEN];
+	char *temp;
+
+	/* Read the voltage scale from the sysfs */
+	ret = asprintf(&temp, "%s/in_voltage_scale", adc->sysfs_dir);
+	if (ret < 0) {
+		fprintf(stdout, "%s: failed to allocate memory\n", __func__);
+		return -ENOMEM;
+	}
+
+	fd = open(temp, O_RDONLY);
+	if (fd < 0) {
+		fprintf(stdout, "%s: failed to open %s\n", __func__, temp);
+		ret = fd;
+		goto free_temp;
+	}
+
+	ret = read(fd, buffer, BUFFER_LEN);
+	if (ret < 0) {
+		fprintf(stdout, "%s: failed to voltage scale from %s (%d)\n",
+			__func__, temp, ret);
+		goto close_fd;
+	}
+
+	if (ret == 0) {
+		fprintf(stdout, "%s: no data available in %s\n", __func__, temp);
+		ret = -ENODATA;
+		goto close_fd;
+	}
+
+	*val = atof(buffer);
+
+close_fd:
+	close(fd);
+free_temp:
+	free(temp);
+	return ret;
+}
+
+int main(int argc, char **argv)
+{
+	adc_t *adc;
+	unsigned long nsamples = 1;
+	unsigned long delay_ms = 1000;
+	long sample_val;
+	bool raw = true;
+	int ret, opt, i;
+
+	if (argc <= 2) {
+		show_usage(0);
+		return EXIT_FAILURE;
+	}
+
+	adc = malloc(sizeof(adc_t));
+	if (!adc) {
+		fprintf(stdout, "Failed to allocate memory\n");
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	memset(adc, 0, sizeof(adc_t));
+
+	adc->channel = ~0;
+
+	while ((opt = getopt(argc, argv, "t:n:d:c:vh")) > 0) {
+		switch (opt) {
+		case 't':
+			adc->data = get_adc_data(optarg);
+			if (!adc->data) {
+				fprintf(stdout, "Unknown ADC type %s\n", optarg);
+				show_usage(0);
+				ret = EXIT_FAILURE;
+				goto error_ret2;
+			}
+			break;
+
+		case 'n':
+			nsamples = strtoul(optarg, NULL, 10);
+			if (!nsamples) {
+				fprintf(stdout,
+					"Invalid number of samples parameter (%s)\n",
+					optarg);
+				show_usage(0);
+				ret = EXIT_FAILURE;
+				goto error_ret2;
+			}
+			break;
+
+		case 'd':
+			delay_ms = strtoul(optarg, NULL, 10);
+			if (!delay_ms) {
+				fprintf(stdout,
+					"Invalid inter sample delay parameter (%s)\n",
+					optarg);
+				show_usage(0);
+				ret = EXIT_FAILURE;
+				goto error_ret2;
+			}
+			break;
+
+		case 'c':
+			adc->channel = strtoul(optarg, NULL, 10);
+			break;
+
+		case 'v':
+			raw = false;
+			break;
+
+		case 'h':
+			show_usage(1);
+			return EXIT_SUCCESS;
+
+		default:
+			show_usage(0);
+			return EXIT_FAILURE;
+		}
+	}
+
+	/* Check that the application params provide what we need */
+	if (!adc->data || adc->data->type == ADC_TYPE_UNKNOWN) {
+		fprintf(stdout, "ADC type must be provided\n");
+		show_usage(1);
+		ret = EXIT_FAILURE;
+		goto error_ret2;
+	}
+
+	if (adc->channel == ~0) {
+		fprintf(stdout, "ADC channel must be provided\n");
+		show_usage(1);
+		ret = EXIT_FAILURE;
+		goto error_ret2;
+	}
+
+	adc->dev_num = find_type_by_name(adc->data->dev_name, "iio:device");
+	if (adc->dev_num < 0) {
+		fprintf(stdout, "Failed to find iio:device for %s\n",
+			adc->data->dev_name);
+		ret = -ENODEV;
+		goto error_ret2;
+	}
+	ret = asprintf(&adc->chrdev_name, "/dev/iio:device%d", adc->dev_num);
+	if (ret < 0) {
+		fprintf(stdout, "Failed to allocate memory\n");
+		ret = -ENOMEM;
+		goto error_ret2;
+	}
+
+	ret = asprintf(&adc->sysfs_dir, "/sys/bus/iio/devices/iio:device%d",
+		       adc->dev_num);
+	if (ret < 0) {
+		fprintf(stdout, "Failed to allocate memory\n");
+		ret = -ENOMEM;
+		goto error_ret3;
+	}
+
+	ret = asprintf(&adc->sysfs_file, "%s/in_voltage%lu_raw",
+		       adc->sysfs_dir, adc->channel);
+	if (ret < 0) {
+		fprintf(stdout, "Failed to allocate memory\n");
+		ret = -ENOMEM;
+		goto error_ret4;
+	}
+
+	if (!raw) {
+		ret = read_voltage_scale(adc, &adc->voltage_scale);
+		if (ret < 0) {
+			goto error_ret5;
+		}
+	}
+
+	for (i = 0; i < nsamples; i++) {
+		ret = read_adc_sample_sysfs(adc, &sample_val);
+		if (ret)
+			break;
+
+		if (raw) {
+			fprintf(stdout, "Sample %i: 0x%04x\n",
+				i, (unsigned int)sample_val);
+		} else {
+			fprintf(stdout, "Sample %i: %.2f V\n",
+				i, sample_val * adc->voltage_scale / 1000);
+		}
+
+		usleep(delay_ms * 1000);
+	}
+
+error_ret5:
+	free(adc->sysfs_file);
+error_ret4:
+	free(adc->sysfs_dir);
+error_ret3:
+	free(adc->chrdev_name);
+error_ret2:
+	free(adc);
+error_ret:
+	return ret;
+}

meta-digi-dey/recipes-digi/dey-examples/files/adc_sample/iio_utils.c

@@ -0,0 +1,669 @@
+/* IIO - useful set of util functionality
+ *
+ * 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 _IIO_UTILS_H
+#define _IIO_UTILS_H
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <dirent.h>
+#include <errno.h>
+#include <ctype.h>
+#include "iio_utils.h"
+
+const char *iio_dir = "/sys/bus/iio/devices/";
+
+static char * const iio_direction[] = {
+	"in",
+	"out",
+};
+
+/**
+ * iioutils_break_up_name() - extract generic name from full channel name
+ * @full_name: the full channel name
+ * @generic_name: the output generic channel name
+ **/
+int iioutils_break_up_name(const char *full_name,
+				  char **generic_name)
+{
+	char *current;
+	char *w, *r;
+	char *working, *prefix = "";
+	int i;
+
+	for (i = 0; i < sizeof(iio_direction) / sizeof(iio_direction[0]); i++)
+		if (!strncmp(full_name, iio_direction[i],
+			     strlen(iio_direction[i]))) {
+			prefix = iio_direction[i];
+			break;
+		}
+
+	current = strdup(full_name + strlen(prefix) + 1);
+	working = strtok(current, "_\0");
+
+	w = working;
+	r = working;
+
+	while (*r != '\0') {
+		if (!isdigit(*r)) {
+			*w = *r;
+			w++;
+		}
+		r++;
+	}
+	*w = '\0';
+	asprintf(generic_name, "%s_%s", prefix, working);
+	free(current);
+
+	return 0;
+}
+
+/**
+ * iioutils_get_type() - find and process _type attribute data
+ * @is_signed: output whether channel is signed
+ * @bytes: output how many bytes the channel storage occupies
+ * @mask: output a bit mask for the raw data
+ * @be: big endian
+ * @device_dir: the iio device directory
+ * @name: the channel name
+ * @generic_name: the channel type name
+ **/
+int iioutils_get_type(unsigned *is_signed,
+			     unsigned *bytes,
+			     unsigned *bits_used,
+			     unsigned *shift,
+			     uint64_t *mask,
+			     unsigned *be,
+			     const char *device_dir,
+			     const char *name,
+			     const char *generic_name)
+{
+	FILE *sysfsfp;
+	int ret;
+	DIR *dp;
+	char *scan_el_dir, *builtname, *builtname_generic, *filename = 0;
+	char signchar, endianchar;
+	unsigned padint;
+	const struct dirent *ent;
+
+	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	ret = asprintf(&builtname, FORMAT_TYPE_FILE, name);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_free_scan_el_dir;
+	}
+	ret = asprintf(&builtname_generic, FORMAT_TYPE_FILE, generic_name);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_free_builtname;
+	}
+
+	dp = opendir(scan_el_dir);
+	if (dp == NULL) {
+		ret = -errno;
+		goto error_free_builtname_generic;
+	}
+	while (ent = readdir(dp), ent != NULL)
+		/*
+		 * Do we allow devices to override a generic name with
+		 * a specific one?
+		 */
+		if ((strcmp(builtname, ent->d_name) == 0) ||
+		    (strcmp(builtname_generic, ent->d_name) == 0)) {
+			ret = asprintf(&filename,
+				       "%s/%s", scan_el_dir, ent->d_name);
+			if (ret < 0) {
+				ret = -ENOMEM;
+				goto error_closedir;
+			}
+			sysfsfp = fopen(filename, "r");
+			if (sysfsfp == NULL) {
+				printf("failed to open %s\n", filename);
+				ret = -errno;
+				goto error_free_filename;
+			}
+
+			ret = fscanf(sysfsfp,
+				     "%ce:%c%u/%u>>%u",
+				     &endianchar,
+				     &signchar,
+				     bits_used,
+				     &padint, shift);
+			if (ret < 0) {
+				printf("failed to pass scan type description\n");
+				ret = -errno;
+				goto error_close_sysfsfp;
+			}
+			*be = (endianchar == 'b');
+			*bytes = padint / 8;
+			if (*bits_used == 64)
+				*mask = ~0;
+			else
+				*mask = (1 << *bits_used) - 1;
+			if (signchar == 's')
+				*is_signed = 1;
+			else
+				*is_signed = 0;
+			fclose(sysfsfp);
+			free(filename);
+
+			filename = 0;
+			sysfsfp = 0;
+		}
+error_close_sysfsfp:
+	if (sysfsfp)
+		fclose(sysfsfp);
+error_free_filename:
+	if (filename)
+		free(filename);
+error_closedir:
+	closedir(dp);
+error_free_builtname_generic:
+	free(builtname_generic);
+error_free_builtname:
+	free(builtname);
+error_free_scan_el_dir:
+	free(scan_el_dir);
+error_ret:
+	return ret;
+}
+
+int iioutils_get_param_float(float *output,
+				    const char *param_name,
+				    const char *device_dir,
+				    const char *name,
+				    const char *generic_name)
+{
+	FILE *sysfsfp;
+	int ret;
+	DIR *dp;
+	char *builtname, *builtname_generic;
+	char *filename = NULL;
+	const struct dirent *ent;
+
+	ret = asprintf(&builtname, "%s_%s", name, param_name);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	ret = asprintf(&builtname_generic,
+		       "%s_%s", generic_name, param_name);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_free_builtname;
+	}
+	dp = opendir(device_dir);
+	if (dp == NULL) {
+		ret = -errno;
+		goto error_free_builtname_generic;
+	}
+	while (ent = readdir(dp), ent != NULL)
+		if ((strcmp(builtname, ent->d_name) == 0) ||
+		    (strcmp(builtname_generic, ent->d_name) == 0)) {
+			ret = asprintf(&filename,
+				       "%s/%s", device_dir, ent->d_name);
+			if (ret < 0) {
+				ret = -ENOMEM;
+				goto error_closedir;
+			}
+			sysfsfp = fopen(filename, "r");
+			if (!sysfsfp) {
+				ret = -errno;
+				goto error_free_filename;
+			}
+			fscanf(sysfsfp, "%f", output);
+			break;
+		}
+error_free_filename:
+	if (filename)
+		free(filename);
+error_closedir:
+	closedir(dp);
+error_free_builtname_generic:
+	free(builtname_generic);
+error_free_builtname:
+	free(builtname);
+error_ret:
+	return ret;
+}
+
+/**
+ * bsort_channel_array_by_index() - reorder so that the array is in index order
+ *
+ **/
+
+void bsort_channel_array_by_index(struct iio_channel_info **ci_array,
+					 int cnt)
+{
+
+	struct iio_channel_info temp;
+	int x, y;
+
+	for (x = 0; x < cnt; x++)
+		for (y = 0; y < (cnt - 1); y++)
+			if ((*ci_array)[y].index > (*ci_array)[y+1].index) {
+				temp = (*ci_array)[y + 1];
+				(*ci_array)[y + 1] = (*ci_array)[y];
+				(*ci_array)[y] = temp;
+			}
+}
+
+/**
+ * build_channel_array() - function to figure out what channels are present
+ * @device_dir: the IIO device directory in sysfs
+ * @
+ **/
+int build_channel_array(const char *device_dir,
+			      struct iio_channel_info **ci_array,
+			      int *counter)
+{
+	DIR *dp;
+	FILE *sysfsfp;
+	int count, i;
+	struct iio_channel_info *current;
+	int ret;
+	const struct dirent *ent;
+	char *scan_el_dir;
+	char *filename;
+
+	*counter = 0;
+	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	dp = opendir(scan_el_dir);
+	if (dp == NULL) {
+		ret = -errno;
+		goto error_free_name;
+	}
+	while (ent = readdir(dp), ent != NULL)
+		if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
+			   "_en") == 0) {
+			ret = asprintf(&filename,
+				       "%s/%s", scan_el_dir, ent->d_name);
+			if (ret < 0) {
+				ret = -ENOMEM;
+				goto error_close_dir;
+			}
+			sysfsfp = fopen(filename, "r");
+			if (sysfsfp == NULL) {
+				ret = -errno;
+				free(filename);
+				goto error_close_dir;
+			}
+			fscanf(sysfsfp, "%i", &ret);
+			if (ret == 1)
+				(*counter)++;
+			fclose(sysfsfp);
+			free(filename);
+		}
+	*ci_array = malloc(sizeof(**ci_array) * (*counter));
+	if (*ci_array == NULL) {
+		ret = -ENOMEM;
+		goto error_close_dir;
+	}
+	seekdir(dp, 0);
+	count = 0;
+	while (ent = readdir(dp), ent != NULL) {
+		if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
+			   "_en") == 0) {
+			int current_enabled = 0;
+
+			current = &(*ci_array)[count++];
+			ret = asprintf(&filename,
+				       "%s/%s", scan_el_dir, ent->d_name);
+			if (ret < 0) {
+				ret = -ENOMEM;
+				/* decrement count to avoid freeing name */
+				count--;
+				goto error_cleanup_array;
+			}
+			sysfsfp = fopen(filename, "r");
+			if (sysfsfp == NULL) {
+				free(filename);
+				ret = -errno;
+				goto error_cleanup_array;
+			}
+			fscanf(sysfsfp, "%i", &current_enabled);
+			fclose(sysfsfp);
+
+			if (!current_enabled) {
+				free(filename);
+				count--;
+				continue;
+			}
+
+			current->scale = 1.0;
+			current->offset = 0;
+			current->name = strndup(ent->d_name,
+						strlen(ent->d_name) -
+						strlen("_en"));
+			if (current->name == NULL) {
+				free(filename);
+				ret = -ENOMEM;
+				goto error_cleanup_array;
+			}
+			/* Get the generic and specific name elements */
+			ret = iioutils_break_up_name(current->name,
+						     &current->generic_name);
+			if (ret) {
+				free(filename);
+				goto error_cleanup_array;
+			}
+			ret = asprintf(&filename,
+				       "%s/%s_index",
+				       scan_el_dir,
+				       current->name);
+			if (ret < 0) {
+				free(filename);
+				ret = -ENOMEM;
+				goto error_cleanup_array;
+			}
+			sysfsfp = fopen(filename, "r");
+			fscanf(sysfsfp, "%u", &current->index);
+			fclose(sysfsfp);
+			free(filename);
+			/* Find the scale */
+			ret = iioutils_get_param_float(&current->scale,
+						       "scale",
+						       device_dir,
+						       current->name,
+						       current->generic_name);
+			if (ret < 0)
+				goto error_cleanup_array;
+			ret = iioutils_get_param_float(&current->offset,
+						       "offset",
+						       device_dir,
+						       current->name,
+						       current->generic_name);
+			if (ret < 0)
+				goto error_cleanup_array;
+			ret = iioutils_get_type(&current->is_signed,
+						&current->bytes,
+						&current->bits_used,
+						&current->shift,
+						&current->mask,
+						&current->be,
+						device_dir,
+						current->name,
+						current->generic_name);
+		}
+	}
+
+	closedir(dp);
+	/* reorder so that the array is in index order */
+	bsort_channel_array_by_index(ci_array, *counter);
+
+	return 0;
+
+error_cleanup_array:
+	for (i = count - 1;  i >= 0; i--)
+		free((*ci_array)[i].name);
+	free(*ci_array);
+error_close_dir:
+	closedir(dp);
+error_free_name:
+	free(scan_el_dir);
+error_ret:
+	return ret;
+}
+
+/**
+ * find_type_by_name() - function to match top level types by name
+ * @name: top level type instance name
+ * @type: the type of top level instance being sort
+ *
+ * Typical types this is used for are device and trigger.
+ **/
+int find_type_by_name(const char *name, const char *type)
+{
+	const struct dirent *ent;
+	int number, numstrlen;
+
+	FILE *nameFile;
+	DIR *dp;
+	char thisname[IIO_MAX_NAME_LENGTH];
+	char *filename;
+
+	dp = opendir(iio_dir);
+	if (dp == NULL) {
+		printf("No industrialio devices available\n");
+		return -ENODEV;
+	}
+
+	while (ent = readdir(dp), ent != NULL) {
+		if (strcmp(ent->d_name, ".") != 0 &&
+			strcmp(ent->d_name, "..") != 0 &&
+			strlen(ent->d_name) > strlen(type) &&
+			strncmp(ent->d_name, type, strlen(type)) == 0) {
+			numstrlen = sscanf(ent->d_name + strlen(type),
+					   "%d",
+					   &number);
+			/* verify the next character is not a colon */
+			if (strncmp(ent->d_name + strlen(type) + numstrlen,
+					":",
+					1) != 0) {
+				filename = malloc(strlen(iio_dir)
+						+ strlen(type)
+						+ numstrlen
+						+ 6);
+				if (filename == NULL) {
+					closedir(dp);
+					return -ENOMEM;
+				}
+				sprintf(filename, "%s%s%d/name",
+					iio_dir,
+					type,
+					number);
+				nameFile = fopen(filename, "r");
+				if (!nameFile) {
+					free(filename);
+					continue;
+				}
+				free(filename);
+				fscanf(nameFile, "%s", thisname);
+				fclose(nameFile);
+				if (strcmp(name, thisname) == 0) {
+					closedir(dp);
+					return number;
+				}
+			}
+		}
+	}
+	closedir(dp);
+	return -ENODEV;
+}
+
+int _write_sysfs_int(char *filename, char *basedir, int val, int verify)
+{
+	int ret = 0;
+	FILE *sysfsfp;
+	int test;
+	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
+
+	if (temp == NULL)
+		return -ENOMEM;
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "w");
+	if (sysfsfp == NULL) {
+		printf("failed to open %s\n", temp);
+		ret = -errno;
+		goto error_free;
+	}
+	fprintf(sysfsfp, "%d", val);
+	fclose(sysfsfp);
+	if (verify) {
+		sysfsfp = fopen(temp, "r");
+		if (sysfsfp == NULL) {
+			printf("failed to open %s\n", temp);
+			ret = -errno;
+			goto error_free;
+		}
+		fscanf(sysfsfp, "%d", &test);
+		fclose(sysfsfp);
+		if (test != val) {
+			printf("Possible failure in int write %d to %s%s\n",
+				val,
+				basedir,
+				filename);
+			ret = -1;
+		}
+	}
+error_free:
+	free(temp);
+	return ret;
+}
+
+int write_sysfs_int(char *filename, char *basedir, int val)
+{
+	return _write_sysfs_int(filename, basedir, val, 0);
+}
+
+int write_sysfs_int_and_verify(char *filename, char *basedir, int val)
+{
+	return _write_sysfs_int(filename, basedir, val, 1);
+}
+
+int _write_sysfs_string(char *filename, char *basedir, char *val, int verify)
+{
+	int ret = 0;
+	FILE  *sysfsfp;
+	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
+
+	if (temp == NULL) {
+		printf("Memory allocation failed\n");
+		return -ENOMEM;
+	}
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "w");
+	if (sysfsfp == NULL) {
+		printf("Could not open %s\n", temp);
+		ret = -errno;
+		goto error_free;
+	}
+	fprintf(sysfsfp, "%s", val);
+	fclose(sysfsfp);
+	if (verify) {
+		sysfsfp = fopen(temp, "r");
+		if (sysfsfp == NULL) {
+			printf("could not open file to verify\n");
+			ret = -errno;
+			goto error_free;
+		}
+		fscanf(sysfsfp, "%s", temp);
+		fclose(sysfsfp);
+		if (strcmp(temp, val) != 0) {
+			printf("Possible failure in string write of %s "
+				"Should be %s "
+				"written to %s\%s\n",
+				temp,
+				val,
+				basedir,
+				filename);
+			ret = -1;
+		}
+	}
+error_free:
+	free(temp);
+
+	return ret;
+}
+
+/**
+ * write_sysfs_string_and_verify() - string write, readback and verify
+ * @filename: name of file to write to
+ * @basedir: the sysfs directory in which the file is to be found
+ * @val: the string to write
+ **/
+int write_sysfs_string_and_verify(char *filename, char *basedir, char *val)
+{
+	return _write_sysfs_string(filename, basedir, val, 1);
+}
+
+int write_sysfs_string(char *filename, char *basedir, char *val)
+{
+	return _write_sysfs_string(filename, basedir, val, 0);
+}
+
+int read_sysfs_posint(char *filename, char *basedir)
+{
+	int ret;
+	FILE  *sysfsfp;
+	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
+
+	if (temp == NULL) {
+		printf("Memory allocation failed");
+		return -ENOMEM;
+	}
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "r");
+	if (sysfsfp == NULL) {
+		ret = -errno;
+		goto error_free;
+	}
+	fscanf(sysfsfp, "%d\n", &ret);
+	fclose(sysfsfp);
+error_free:
+	free(temp);
+	return ret;
+}
+
+int read_sysfs_float(char *filename, char *basedir, float *val)
+{
+	int ret = 0;
+	FILE  *sysfsfp;
+	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
+
+	if (temp == NULL) {
+		printf("Memory allocation failed");
+		return -ENOMEM;
+	}
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "r");
+	if (sysfsfp == NULL) {
+		ret = -errno;
+		goto error_free;
+	}
+	fscanf(sysfsfp, "%f\n", val);
+	fclose(sysfsfp);
+error_free:
+	free(temp);
+	return ret;
+}
+
+int read_sysfs_string(const char *filename, const char *basedir, char *str)
+{
+	int ret = 0;
+	FILE  *sysfsfp;
+	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
+
+	if (temp == NULL) {
+		printf("Memory allocation failed");
+		return -ENOMEM;
+	}
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "r");
+	if (sysfsfp == NULL) {
+		ret = -errno;
+		goto error_free;
+	}
+	fscanf(sysfsfp, "%s\n", str);
+	fclose(sysfsfp);
+error_free:
+	free(temp);
+	return ret;
+}
+
+#endif /* _IIO_UTILS_H */

meta-digi-dey/recipes-digi/dey-examples/files/adc_sample/iio_utils.h

@@ -0,0 +1,71 @@
+#ifndef _IIO_UTILS_H_
+#define _IIO_UTILS_H_
+
+/* IIO - useful set of util functionality
+ *
+ * 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.
+ */
+
+#include <stdint.h>
+
+/* Made up value to limit allocation sizes */
+#define IIO_MAX_NAME_LENGTH 30
+
+#define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
+#define FORMAT_TYPE_FILE "%s_type"
+
+extern const char *iio_dir;
+
+/**
+ * struct iio_channel_info - information about a given channel
+ * @name: channel name
+ * @generic_name: general name for channel type
+ * @scale: scale factor to be applied for conversion to si units
+ * @offset: offset to be applied for conversion to si units
+ * @index: the channel index in the buffer output
+ * @bytes: number of bytes occupied in buffer output
+ * @mask: a bit mask for the raw output
+ * @is_signed: is the raw value stored signed
+ * @enabled: is this channel enabled
+ **/
+struct iio_channel_info {
+	char *name;
+	char *generic_name;
+	float scale;
+	float offset;
+	unsigned index;
+	unsigned bytes;
+	unsigned bits_used;
+	unsigned shift;
+	uint64_t mask;
+	unsigned be;
+	unsigned is_signed;
+	unsigned location;
+};
+
+int iioutils_break_up_name(const char *full_name, char **generic_name);
+int iioutils_get_type(unsigned *is_signed, unsigned *bytes,
+					  unsigned *bits_used, unsigned *shift,
+					  uint64_t *mask, unsigned *be,
+					  const char *device_dir, const char *name,
+					  const char *generic_name);
+int iioutils_get_param_float(float *output, const char *param_name,
+							 const char *device_dir, const char *name,
+							 const char *generic_name);
+void bsort_channel_array_by_index(struct iio_channel_info **ci_array, int cnt);
+int build_channel_array(const char *device_dir,
+						struct iio_channel_info **ci_array, int *counter);
+int find_type_by_name(const char *name, const char *type);
+int write_sysfs_int(char *filename, char *basedir, int val);
+int write_sysfs_int_and_verify(char *filename, char *basedir, int val);
+int write_sysfs_string_and_verify(char *filename, char *basedir, char *val);
+int write_sysfs_string(char *filename, char *basedir, char *val);
+int read_sysfs_posint(char *filename, char *basedir);
+int read_sysfs_float(char *filename, char *basedir, float *val);
+int read_sysfs_string(const char *filename, const char *basedir, char *str);
+
+#endif /* _IIO_UTILS_H_ */

meta-digi-dey/recipes-digi/packagegroups/packagegroup-dey-examples.bb

@@ -38,6 +38,7 @@ RDEPENDS_${PN}_append_ccimx6 = "\
 RDEPENDS_${PN}_append_ccimx6ul = "\
 	${@bb.utils.contains("MACHINE_FEATURES", "bluetooth", "dey-examples-bt", "", d)} \
 	${@bb.utils.contains("MACHINE_FEATURES", "bluetooth", "dey-examples-btconfig", "", d)} \
+	dey-examples-adc \
 	dey-examples-can \
 	${@bb.utils.contains("MACHINE_FEATURES", "bluetooth", "dey-examples-hdp", "", d)} \
 	dey-examples-tamper \