Add test for ADC pins

boards/test_stm32f405_feather/test_stm32f405_feather.dts

@@ -107,6 +107,11 @@
 	status = "okay";
 };
 
+&adc1 {
+	st,adc-prescaler = <2>;
+	status = "okay";
+};
+
 zephyr_udc0: &usbotg_fs {
 	pinctrl-0 = <&usb_otg_fs_dm_pa11 &usb_otg_fs_dp_pa12>;
 	pinctrl-names = "default";

samples/test_adc/CMakeLists.txt

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(test_adc)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

samples/test_adc/VERSION

@@ -0,0 +1,5 @@
+VERSION_MAJOR = 0
+VERSION_MINOR = 0
+PATCHLEVEL = 0
+VERSION_TWEAK = 0
+EXTRAVERSION =

samples/test_adc/boards/test_stm32f405_feather.overlay

@@ -0,0 +1,67 @@
+/* Copyright (c) 2025 Lucian Copeland for Adafruit Industries
+   SPDX-License-Identifier: Apache-2.0 */
+
+   / {
+	zephyr,user {
+		/* adjust channel number according to pinmux in board.dts */
+		io-channels = <&adc1 4>, <&adc1 5>, <&adc1 6>, <&adc1 7>, <&adc1 14>, <&adc1 15>;
+	};
+};
+
+&adc1 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	pinctrl-0 = <&adc1_in4_pa4>, <&adc1_in5_pa5>, <&adc1_in6_pa6>, <&adc1_in7_pa7>,
+                <&adc1_in14_pc4>, <&adc1_in15_pc5>;
+    pinctrl-names = "default";
+
+	/* Define ADC channels */
+	channel@4 {
+		reg = <4>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+
+	channel@5 {
+		reg = <5>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+
+	channel@6 {
+		reg = <6>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+
+	channel@7 {
+		reg = <7>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+
+	channel@14 {
+		reg = <14>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+
+	channel@15 {
+		reg = <15>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_INTERNAL";
+		zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+		zephyr,resolution = <12>;
+	};
+};

samples/test_adc/prj.conf

@@ -0,0 +1 @@
+CONFIG_ADC=y

samples/test_adc/src/main.c

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2020 Libre Solar Technologies GmbH
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <inttypes.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <zephyr/device.h>
+#include <zephyr/devicetree.h>
+#include <zephyr/drivers/adc.h>
+#include <zephyr/kernel.h>
+#include <zephyr/sys/printk.h>
+#include <zephyr/sys/util.h>
+
+#if !DT_NODE_EXISTS(DT_PATH(zephyr_user)) || \
+	!DT_NODE_HAS_PROP(DT_PATH(zephyr_user), io_channels)
+#error "No suitable devicetree overlay specified"
+#endif
+
+#define DT_SPEC_AND_COMMA(node_id, prop, idx) \
+	ADC_DT_SPEC_GET_BY_IDX(node_id, idx),
+
+/* Data of ADC io-channels specified in devicetree. */
+static const struct adc_dt_spec adc_channels[] = {
+	DT_FOREACH_PROP_ELEM(DT_PATH(zephyr_user), io_channels,
+			     DT_SPEC_AND_COMMA)
+};
+
+int main(void)
+{
+	int err;
+	uint32_t count = 0;
+	uint16_t buf;
+	struct adc_sequence sequence = {
+		.buffer = &buf,
+		/* buffer size in bytes, not number of samples */
+		.buffer_size = sizeof(buf),
+	};
+
+	/* Configure channels individually prior to sampling. */
+	for (size_t i = 0U; i < ARRAY_SIZE(adc_channels); i++) {
+		if (!adc_is_ready_dt(&adc_channels[i])) {
+			printk("ADC controller device %s not ready\n", adc_channels[i].dev->name);
+			return 0;
+		}
+
+		err = adc_channel_setup_dt(&adc_channels[i]);
+		if (err < 0) {
+			printk("Could not setup channel #%d (%d)\n", i, err);
+			return 0;
+		}
+	}
+
+#ifndef CONFIG_COVERAGE
+	while (1) {
+#else
+	for (int k = 0; k < 10; k++) {
+#endif
+		printk("ADC reading[%u]:\n", count++);
+		for (size_t i = 0U; i < ARRAY_SIZE(adc_channels); i++) {
+			int32_t val_mv;
+
+			printk("- %s, channel %d: ",
+			       adc_channels[i].dev->name,
+			       adc_channels[i].channel_id);
+
+			(void)adc_sequence_init_dt(&adc_channels[i], &sequence);
+
+			err = adc_read_dt(&adc_channels[i], &sequence);
+			if (err < 0) {
+				printk("Could not read (%d)\n", err);
+				continue;
+			}
+
+			/*
+			 * If using differential mode, the 16 bit value
+			 * in the ADC sample buffer should be a signed 2's
+			 * complement value.
+			 */
+			if (adc_channels[i].channel_cfg.differential) {
+				val_mv = (int32_t)((int16_t)buf);
+			} else {
+				val_mv = (int32_t)buf;
+			}
+			printk("%"PRId32, val_mv);
+			err = adc_raw_to_millivolts_dt(&adc_channels[i],
+						       &val_mv);
+			/* conversion to mV may not be supported, skip if not */
+			if (err < 0) {
+				printk(" (value in mV not available)\n");
+			} else {
+				printk(" = %"PRId32" mV\n", val_mv);
+			}
+		}
+
+		k_sleep(K_MSEC(1000));
+	}
+	return 0;
+}