tests: drivers: Add test for temperature sensor

Add a simple test intended primarily for checking the nRF temperature
sensor in its nrfs variant but intentionally was made generic enough
that it should be usable with other temperature sensors (after just
providing an overlay) and could be helpful in development of new
temperature sensor drivers, and possibly extended then if needed.

Signed-off-by: Andrzej Głąbek <andrzej.glabek@nordicsemi.no>

tests/drivers/sensor/temp_sensor/CMakeLists.txt

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(temp_sensor)
+
+FILE(GLOB app_sources src/*.c)
+
+target_sources(app PRIVATE ${app_sources})

tests/drivers/sensor/temp_sensor/boards/nrf52840dk_nrf52840.overlay

@@ -0,0 +1,3 @@
+temp_sensor: &temp {
+	status = "okay";
+};

tests/drivers/sensor/temp_sensor/boards/nrf54h20dk_nrf54h20_cpuapp.conf

@@ -0,0 +1,2 @@
+CONFIG_NRFS=y
+CONFIG_TEMP_NRFS_TRIGGER_OWN_THREAD=y

tests/drivers/sensor/temp_sensor/boards/nrf54h20dk_nrf54h20_cpuapp.overlay

@@ -0,0 +1,3 @@
+temp_sensor: &temp_nrfs {
+	status = "okay";
+};

tests/drivers/sensor/temp_sensor/prj.conf

@@ -0,0 +1,2 @@
+CONFIG_ZTEST=y
+CONFIG_SENSOR=y

tests/drivers/sensor/temp_sensor/src/main.c

@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2024, Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/ztest.h>
+#include <zephyr/device.h>
+#include <zephyr/drivers/sensor.h>
+
+static const struct device *temp_dev = DEVICE_DT_GET(DT_NODELABEL(temp_sensor));
+static enum sensor_channel chan_to_use; /* this is filled by before() */
+
+static volatile bool trigger_handler_called;
+
+ZTEST(temp_sensor, test_polling)
+{
+	int rc;
+	int cnt;
+	struct sensor_value val;
+
+	cnt = 0;
+	while (1) {
+		int32_t temp_val;
+
+		rc = sensor_sample_fetch_chan(temp_dev, chan_to_use);
+		zassert_ok(rc, "Cannot fetch chan sample: %d.", rc);
+
+		rc = sensor_channel_get(temp_dev, chan_to_use, &val);
+		zassert_ok(rc, "Cannot read from channel %d: %d.",
+			   chan_to_use, rc);
+
+		temp_val = (val.val1 * 100) + (val.val2 / 10000);
+		TC_PRINT("Temperature: %d.%02u\n",
+			temp_val/100, abs(temp_val) % 100);
+
+		++cnt;
+		if (cnt >= 5) {
+			break;
+		}
+
+		k_sleep(K_MSEC(500));
+	}
+}
+
+static void trigger_handler(const struct device *temp_dev,
+			    const struct sensor_trigger *trig)
+{
+	ARG_UNUSED(temp_dev);
+	ARG_UNUSED(trig);
+
+	trigger_handler_called = true;
+}
+
+ZTEST(temp_sensor, test_trigger)
+{
+	int rc;
+	struct sensor_value val;
+	struct sensor_trigger trig = { .type = SENSOR_TRIG_THRESHOLD,
+				       .chan = chan_to_use };
+
+	/* Check if the sensor allows setting a threshold trigger.
+	 * If not, skip the test.
+	 */
+	rc = sensor_trigger_set(temp_dev, &trig, NULL);
+	if (rc == -ENOSYS || rc == -ENOTSUP) {
+		TC_PRINT("This sensor does not support threshold trigger.\n");
+		ztest_test_skip();
+	}
+
+	rc = sensor_channel_get(temp_dev, chan_to_use, &val);
+	zassert_ok(rc, "Cannot read from channel %d: %d.",
+			chan_to_use, rc);
+
+	/* Set the upper threshold somewhat below the temperature read above. */
+	val.val1 -= 5;
+	rc = sensor_attr_set(temp_dev, chan_to_use,
+			     SENSOR_ATTR_UPPER_THRESH, &val);
+	zassert_ok(rc, "Cannot set upper threshold: %d.", rc);
+
+	/* And the lower threshold below the upper one. */
+	val.val1 -= 1;
+	rc = sensor_attr_set(temp_dev, chan_to_use,
+			     SENSOR_ATTR_LOWER_THRESH, &val);
+	zassert_ok(rc, "Cannot set lower threshold: %d.", rc);
+
+	/* Set sampling frequency to 10 Hz, to expect a trigger after 100 ms. */
+	val.val1 = 10;
+	val.val2 = 0;
+	rc = sensor_attr_set(temp_dev, chan_to_use,
+			     SENSOR_ATTR_SAMPLING_FREQUENCY, &val);
+	zassert_ok(rc, "Cannot set sampling frequency: %d.", rc);
+
+	trigger_handler_called = false;
+
+	rc = sensor_trigger_set(temp_dev, &trig, trigger_handler);
+	zassert_ok(rc, "Cannot enable the trigger: %d.", rc);
+
+	k_sleep(K_MSEC(300));
+	zassert_true(trigger_handler_called);
+
+	rc = sensor_trigger_set(temp_dev, &trig, NULL);
+	zassert_ok(rc, "Cannot disable the trigger: %d.", rc);
+
+	trigger_handler_called = false;
+
+	k_sleep(K_MSEC(300));
+	zassert_false(trigger_handler_called);
+}
+
+static void before(void *fixture)
+{
+	ARG_UNUSED(fixture);
+
+	int rc;
+	int cnt;
+	struct sensor_value val;
+
+	zassert_true(device_is_ready(temp_dev),
+		"Device %s is not ready.", temp_dev->name);
+
+	cnt = 0;
+	/* Try to fetch a sample to check if the sensor is ready to work.
+	 * Try several times if it appears to be needing a while for some
+	 * initialization of communication etc.
+	 */
+	while (1) {
+		rc = sensor_sample_fetch(temp_dev);
+		if (rc != -EAGAIN && rc != -ENOTCONN) {
+			break;
+		}
+
+		++cnt;
+		zassert_false(cnt >= 3, "Cannot fetch a sample: %d.", rc);
+
+		k_sleep(K_MSEC(1000));
+	}
+	zassert_ok(rc, "Cannot fetch a sample: %d.", rc);
+
+	/* Check if the sensor provides the die temperature.
+	 * If not, switch to the ambient one.
+	 */
+	chan_to_use = SENSOR_CHAN_DIE_TEMP;
+	rc = sensor_channel_get(temp_dev, chan_to_use, &val);
+	if (rc == -ENOTSUP) {
+		chan_to_use = SENSOR_CHAN_AMBIENT_TEMP;
+	}
+}
+
+ZTEST_SUITE(temp_sensor, NULL, NULL, before, NULL, NULL);

tests/drivers/sensor/temp_sensor/testcase.yaml

@@ -0,0 +1,9 @@
+tests:
+  drivers.sensor.temp_sensor:
+    tags:
+      - drivers
+      - sensors
+    filter: dt_nodelabel_enabled("temp_sensor")
+    integration_platforms:
+      - nrf52840dk/nrf52840
+      - nrf54h20dk/nrf54h20/cpuapp