tests: drivers: adc: Add tests support for ADC driver on Renesas EK-RA2A1 board

Add Renesas EK-RA2A1 board support for these tests:

- tests/drivers/adc/adc_api
- tests/drivers/adc/adc_accuracy_test

Signed-off-by: Thinh Le Cong <[email protected]>

Author: Thinh Le Cong

tests/drivers/adc/adc_accuracy_test/boards/ek_ra2a1.conf

@@ -0,0 +1,4 @@
+# Copyright (c) 2025 Renesas Electronics Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_DAC_BUFFER_NOT_SUPPORTED=y

tests/drivers/adc/adc_accuracy_test/boards/ek_ra2a1.overlay

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2024-2025 Renesas Electronics Corporation 
+ *
+ * SPDX-License-Identifier: Apache-2.0 
+ */
+
+/ {
+	zephyr,user {
+		io-channels = <&adc0 2>;
+		reference-mv = <3300>;
+		expected-accuracy = <32>;
+	};
+};
+
+&pinctrl {
+	adc0_default: adc0_default {
+		group1 {
+			/* input */
+			psels = <RA_PSEL(RA_PSEL_ADC, 5, 2)>;
+			renesas,analog-enable;
+		};
+	};
+};
+
+&adc0{
+	pinctrl-0 = <&adc0_default>;
+	pinctrl-names = "default";
+	#address-cells = <1>;
+	#size-cells = <0>;
+	interrupts = <31 1>;
+	interrupt-names = "scanend";
+	status = "okay";
+
+	/*
+	 * Channel 2 is used in single ended mode, with 15 bit resolution
+	 */
+	channel@2 { 
+		reg = <2>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_EXTERNAL0";
+		zephyr,acquisition-time = <0>;
+		zephyr,resolution = <15>;
+		zephyr,vref-mv = <3300>;
+	};
+};

tests/drivers/adc/adc_accuracy_test/src/dac_source.c

@@ -43,6 +43,9 @@ static int test_dac_to_adc(void)
 	struct adc_sequence sequence = {
 		.buffer      = &sample_buffer,
 		.buffer_size = sizeof(sample_buffer),
+#if DT_HAS_COMPAT_STATUS_OKAY(renesas_ra_adc)
+		.calibrate = true,
+#endif
 	};
 
 	const struct device *dac_dev = init_dac();

tests/drivers/adc/adc_api/boards/ek_ra2a1.overlay

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2025 Renesas Electronics Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	zephyr,user {
+		io-channels = <&adc0 0>, <&adc0 1>;
+	};
+};
+
+&pinctrl {
+	adc0_default: adc0_default {
+		group1 {
+			/* input */
+			psels = <RA_PSEL(RA_PSEL_ADC, 5, 0)>,
+				<RA_PSEL(RA_PSEL_ADC, 5, 1)>;
+			renesas,analog-enable;
+		};
+	};
+};
+
+&adc0 {
+	pinctrl-0 = <&adc0_default>;
+	pinctrl-names = "default";
+	status = "okay";
+	#address-cells = <1>;
+	#size-cells = <0>;
+	interrupts = <31 1>;
+	interrupt-names = "scanend";
+
+	/*
+	 * Channel 0 is used in single ended mode, with 15 bit resolution
+	 */
+	channel@0 {
+		reg = <0>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_EXTERNAL0";
+		zephyr,resolution = <15>;
+		zephyr,acquisition-time = <0>;
+		zephyr,vref-mv = <3300>;
+	};
+
+	channel@1 {
+		reg = <1>;
+		zephyr,gain = "ADC_GAIN_1";
+		zephyr,reference = "ADC_REF_EXTERNAL0";
+		zephyr,resolution = <15>;
+		zephyr,acquisition-time = <0>;
+		zephyr,vref-mv = <3300>;
+	};
+};

tests/drivers/adc/adc_api/src/test_adc.c

@@ -136,6 +136,9 @@ static int test_task_one_channel(void)
 	struct adc_sequence sequence = {
 		.buffer = m_sample_buffer,
 		.buffer_size = sizeof(m_sample_buffer),
+#if DT_HAS_COMPAT_STATUS_OKAY(renesas_ra_adc)
+		.calibrate = true,
+#endif
 	};
 
 	init_adc();
@@ -163,6 +166,9 @@ static int test_task_multiple_channels(void)
 	struct adc_sequence sequence = {
 		.buffer      = m_sample_buffer,
 		.buffer_size = sizeof(m_sample_buffer),
+#if DT_HAS_COMPAT_STATUS_OKAY(renesas_ra_adc)
+		.calibrate = true,
+#endif
 	};
 
 	init_adc();
@@ -210,6 +216,9 @@ static int test_task_asynchronous_call(void)
 		.options     = &options,
 		.buffer      = m_sample_buffer,
 		.buffer_size = sizeof(m_sample_buffer),
+#if DT_HAS_COMPAT_STATUS_OKAY(renesas_ra_adc)
+		.calibrate = true,
+#endif
 	};
 	struct k_poll_event  async_evt =
 		K_POLL_EVENT_INITIALIZER(K_POLL_TYPE_SIGNAL,
@@ -272,6 +281,9 @@ static int test_task_with_interval(void)
 		.options     = &options,
 		.buffer      = m_sample_buffer,
 		.buffer_size = sizeof(m_sample_buffer),
+#if DT_HAS_COMPAT_STATUS_OKAY(renesas_ra_adc)
+		.calibrate = true,
+#endif
 	};
 
 	init_adc();
@@ -349,6 +361,9 @@ static int test_task_repeated_samplings(void)
 		.options     = &options,
 		.buffer      = m_sample_buffer,
 		.buffer_size = sizeof(m_sample_buffer),
+#if DT_HAS_COMPAT_STATUS_OKAY(renesas_ra_adc)
+		.calibrate = true,
+#endif
 	};
 
 	init_adc();
@@ -383,6 +398,9 @@ static int test_task_invalid_request(void)
 		.buffer      = m_sample_buffer,
 		.buffer_size = sizeof(m_sample_buffer),
 		.resolution  = 0, /* intentionally invalid value */
+#if DT_HAS_COMPAT_STATUS_OKAY(renesas_ra_adc)
+		.calibrate = true,
+#endif
 	};
 
 	init_adc();