samples: drivers: Add comparator samples

Adds comparator samples which:
- set and monitors trigger using callback
- set and periodically checks if trigger is pending

Signed-off-by: Bjarki Arge Andreasen <[email protected]>

samples/drivers/comparator/callback/CMakeLists.txt

@@ -0,0 +1,8 @@
+# Copyright (c) 2024 Nordic Semiconductor
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(sample)
+
+target_sources(app PRIVATE src/main.c)

samples/drivers/comparator/callback/README.rst

@@ -0,0 +1,28 @@
+.. zephyr:code-sample:: comparator_callback
+   :name: Comparator callback
+   :relevant-api: comparator_interface
+
+   Monitor the output of a comparator
+
+Overview
+********
+
+This sample demonstrates how to monitor the output from a comparator
+using the comparator device driver API.
+
+Requirements
+************
+
+This sample requires a board with a comparator device present and enabled
+in the devicetree. The comparator shall be pointed to by the devicetree alias
+``comparator``.
+
+Sample Output
+*************
+
+.. code-block:: console
+
+   comparator output is high
+   comparator output is low
+   comparator output is high
+   comparator output is low

samples/drivers/comparator/callback/boards/frdm_ke15z_mke15z7.overlay

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <nxp/kinetis/MKE17Z256VLL7-pinctrl.h>
+
+/{
+	aliases {
+		comparator = &cmp0;
+	};
+};
+
+&pinctrl {
+	cmp0_default: cmp0_default {
+		group0 {
+			pinmux = <ACMP0_IN0_PTA0>,
+				 <ACMP0_IN1_PTA1>;
+
+			/* required but not used */
+			drive-strength = "high";
+		};
+	};
+};
+
+&cmp0 {
+	pinctrl-0 = <&cmp0_default>;
+	pinctrl-names = "default";
+	status = "okay";
+
+	positive-mux-input = "IN0";
+	positive-port-input = "MUX";
+	negative-mux-input = "IN1";
+	negative-port-input = "MUX";
+};

samples/drivers/comparator/callback/boards/nrf5340dk_nrf5340_cpuapp.overlay

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/{
+	aliases {
+		comparator = ∁
+	};
+};
+
+&comp {
+	positive-input = "INPUT_0"; /* P0.04 */
+	external-reference = "EXT_REF_1"; /* P0.05 */
+	main-mode = "DIFF";
+	speed-mode = "NORMAL";
+	hysteresis = "50MV";
+	isource = "OFF";
+	status = "okay";
+};

samples/drivers/comparator/callback/prj.conf

@@ -0,0 +1,4 @@
+# Copyright (c) 2024 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_COMPARATOR=y

samples/drivers/comparator/callback/sample.yaml

@@ -0,0 +1,11 @@
+# Copyright (c) 2024 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+sample:
+  name: Comparator callback sample
+tests:
+  sample.drivers.comparator.callback:
+    tags:
+      - drivers
+      - comparator
+    filter: dt_alias_exists("comparator")

samples/drivers/comparator/callback/src/main.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/drivers/comparator.h>
+#include <zephyr/kernel.h>
+#include <stdio.h>
+
+const struct device *sample_comparator = DEVICE_DT_GET(DT_ALIAS(comparator));
+
+static void sample_get_output_handler(struct k_work *work)
+{
+	int ret;
+
+	ARG_UNUSED(work);
+
+	ret = comparator_get_output(sample_comparator);
+	if (ret == 1) {
+		printf("comparator output is %s\n", "high");
+	} else if (ret == 0) {
+		printf("comparator output is %s\n", "low");
+	} else {
+		printf("failed to get comparator output (ret = %i)\n", ret);
+	}
+}
+
+K_WORK_DEFINE(sample_get_output_work, sample_get_output_handler);
+
+static void sample_callback(const struct device *dev, void *user_data)
+{
+	ARG_UNUSED(dev);
+	ARG_UNUSED(user_data);
+
+	k_work_submit(&sample_get_output_work);
+}
+
+int main(void)
+{
+	int ret;
+
+	ret = comparator_set_trigger(sample_comparator, COMPARATOR_TRIGGER_BOTH_EDGES);
+	if (ret < 0) {
+		printf("failed to set comparator trigger (ret = %i)\n", ret);
+	}
+
+	ret = comparator_set_trigger_callback(sample_comparator,
+					      sample_callback,
+					      NULL);
+	if (ret < 0) {
+		printf("failed to set comparator callback (ret = %i)\n", ret);
+	}
+
+	k_work_submit(&sample_get_output_work);
+	return 0;
+}

samples/drivers/comparator/pending/CMakeLists.txt

@@ -0,0 +1,8 @@
+# Copyright (c) 2024 Nordic Semiconductor
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(sample)
+
+target_sources(app PRIVATE src/main.c)

samples/drivers/comparator/pending/README.rst

@@ -0,0 +1,32 @@
+.. zephyr:code-sample:: comparator_pending
+   :name: Comparator pending
+   :relevant-api: comparator_interface
+
+   Monitor the output of a comparator
+
+Overview
+********
+
+This sample demonstrates how to enable the comparator trigger and
+periodically check and clear the trigger pending flag using the
+comparator device driver API.
+
+Requirements
+************
+
+This sample requires a board with a comparator device present and enabled
+in the devicetree. The comparator shall be pointed to by the devicetree alias
+``comparator``.
+
+Sample Output
+*************
+
+.. code-block:: console
+
+   comparator trigger is not pending
+   comparator trigger is not pending
+   comparator trigger is not pending
+   comparator trigger is not pending
+   comparator trigger is pending
+   comparator trigger is not pending
+   comparator trigger is not pending

samples/drivers/comparator/pending/boards/frdm_ke15z_mke15z7.overlay

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <nxp/kinetis/MKE17Z256VLL7-pinctrl.h>
+
+/{
+	aliases {
+		comparator = &cmp0;
+	};
+};
+
+&pinctrl {
+	cmp0_default: cmp0_default {
+		group0 {
+			pinmux = <ACMP0_IN0_PTA0>,
+				 <ACMP0_IN1_PTA1>;
+
+			/* required but not used */
+			drive-strength = "high";
+		};
+	};
+};
+
+&cmp0 {
+	pinctrl-0 = <&cmp0_default>;
+	pinctrl-names = "default";
+	status = "okay";
+
+	positive-mux-input = "IN0";
+	positive-port-input = "MUX";
+	negative-mux-input = "IN1";
+	negative-port-input = "MUX";
+};

samples/drivers/comparator/pending/boards/nrf5340dk_nrf5340_cpuapp.overlay

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/{
+	aliases {
+		comparator = ∁
+	};
+};
+
+&comp {
+	positive-input = "INPUT_0"; /* P0.04 */
+	external-reference = "EXT_REF_1"; /* P0.05 */
+	main-mode = "DIFF";
+	speed-mode = "NORMAL";
+	hysteresis = "50MV";
+	isource = "OFF";
+	status = "okay";
+};

samples/drivers/comparator/pending/prj.conf

@@ -0,0 +1,4 @@
+# Copyright (c) 2024 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_COMPARATOR=y

samples/drivers/comparator/pending/sample.yaml

@@ -0,0 +1,11 @@
+# Copyright (c) 2024 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+sample:
+  name: Comparator pending sample
+tests:
+  sample.drivers.comparator.pending:
+    tags:
+      - drivers
+      - comparator
+    filter: dt_alias_exists("comparator")

samples/drivers/comparator/pending/src/main.c

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/drivers/comparator.h>
+#include <zephyr/kernel.h>
+#include <stdio.h>
+
+const struct device *sample_comparator = DEVICE_DT_GET(DT_ALIAS(comparator));
+
+int main(void)
+{
+	int ret;
+
+	ret = comparator_set_trigger(sample_comparator, COMPARATOR_TRIGGER_BOTH_EDGES);
+	if (ret < 0) {
+		printf("failed to set comparator trigger (ret = %i)\n", ret);
+	}
+
+	while (1) {
+		k_msleep(1000);
+		ret = comparator_trigger_is_pending(sample_comparator);
+		if (ret == 1) {
+			printf("comparator trigger is %s\n", "pending");
+		} else if (ret == 0) {
+			printf("comparator trigger is %s\n", "not pending");
+		} else {
+			printf("failed to check if trigger is pending (ret = %i)\n", ret);
+		}
+	}
+
+	return 0;
+}