gpio: Add tests for software based GPIO debounce driver

Add tests to validate software based GPIO debounce driver.

Signed-off-by: Al Semjonovs <[email protected]>

Author: asemjonovs

tests/drivers/gpio/gpio_api_1pin/boards/native_posix.overlay

@@ -5,5 +5,31 @@
  */
 
 &gpio0 {
-	ngpios = <2>;
+	ngpios = <3>;
+};
+
+/ {
+	gpio-keys0 {
+		compatible = "zephyr,gpio-keys";
+		debounce-interval-ms = <30>;
+
+		voldown_button: button_0 {
+			gpios = <&gpio0 0 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
+			zephyr,code = <10>;
+		};
+		volup_button: button_1 {
+			gpios = <&gpio0 1 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
+			zephyr,code = <11>;
+		};
+	};
+
+	gpio-keys1 {
+		compatible = "zephyr,gpio-keys";
+		debounce-interval-ms = <100>;
+
+		power_button: button_2 {
+			gpios = <&gpio0 2 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
+			zephyr,code = <20>;
+		};
+	};
 };

tests/drivers/gpio/gpio_api_1pin/src/test_gpio_keys.c

@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2022 Google LLC
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include "zephyr/sys/util.h"
+#include <zephyr/device.h>
+#include <zephyr/drivers/gpio/gpio_emul.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/ztest.h>
+
+#include <zephyr/drivers/gpio_keys.h>
+
+LOG_MODULE_REGISTER(gpio_keys_test, LOG_LEVEL_DBG);
+
+#if DT_NODE_EXISTS(DT_NODELABEL(voldown_button))
+
+const struct device *test_gpio_keys_dev = DEVICE_DT_GET(DT_PARENT(DT_NODELABEL(voldown_button)));
+#define BUTTON_0_IDX DT_NODE_CHILD_IDX(DT_NODELABEL(voldown_button))
+#define BUTTON_1_IDX DT_NODE_CHILD_IDX(DT_NODELABEL(volup_button))
+
+struct gpio_keys_pin_config {
+	/** GPIO specification from devicetree */
+	struct gpio_dt_spec spec;
+	/** Zephyr code from devicetree */
+	uint32_t zephyr_code;
+};
+struct gpio_keys_config {
+	/** Debounce interval in milliseconds from devicetree */
+	uint32_t debounce_interval_ms;
+	const int num_keys;
+	const struct gpio_keys_pin_config *pin_cfg;
+};
+
+/**
+ * @brief Test Suite: Verifies gpio_keys_config functionality.
+ */
+ZTEST_SUITE(gpio_keys, NULL, NULL, NULL, NULL, NULL);
+
+/**
+ * @brief TestPurpose: Verify gpio_keys_config pressed raw.
+ *
+ */
+ZTEST(gpio_keys, test_gpio_keys_pressed)
+{
+	const struct gpio_keys_config *config = test_gpio_keys_dev->config;
+	const struct gpio_keys_pin_config *pin_cfg = &config->pin_cfg[BUTTON_0_IDX];
+	const struct gpio_dt_spec *spec = &pin_cfg->spec;
+
+	zassert_ok(gpio_pin_configure(spec->port, spec->pin, GPIO_INPUT));
+
+	zassert_ok(gpio_emul_input_set(spec->port, spec->pin, 1));
+	zassert_equal(1, gpio_keys_get_pin(test_gpio_keys_dev, BUTTON_0_IDX));
+
+	zassert_ok(gpio_emul_input_set(spec->port, spec->pin, 0));
+	zassert_equal(0, gpio_keys_get_pin(test_gpio_keys_dev, BUTTON_0_IDX));
+}
+
+/**
+ * @brief TestPurpose: Verify button interrupt.
+ *
+ */
+uint32_t gpio_keys_interrupt_called;
+void test_gpio_keys_cb_handler(const struct device *dev, struct gpio_keys_callback *cbdata,
+			       uint32_t pins)
+{
+	LOG_DBG("GPIO_KEY %s pressed, pins=%d, zephyr_code=%u, pin_state=%d", dev->name, pins,
+		cbdata->zephyr_code, cbdata->pin_state);
+	gpio_keys_interrupt_called = cbdata->zephyr_code;
+}
+
+ZTEST(gpio_keys, test_gpio_keys_interrupt)
+{
+	int button_idx[] = {BUTTON_0_IDX, BUTTON_1_IDX};
+	int num_gpio_keys = ARRAY_SIZE(button_idx);
+	const struct gpio_keys_config *config = test_gpio_keys_dev->config;
+	const struct gpio_keys_pin_config *pin_cfg;
+	const struct gpio_dt_spec *spec;
+
+	for (int i = 0; i < num_gpio_keys; i++) {
+		pin_cfg = &config->pin_cfg[button_idx[i]];
+		spec = &pin_cfg->spec;
+
+		LOG_DBG("GPIO_KEY config=[0x%p, %d]", config->debounce_interval_ms,
+			pin_cfg->zephyr_code);
+		LOG_DBG("GPIO_KEY spec=[0x%p, %d]", spec->port, spec->pin);
+
+		zassert_ok(gpio_pin_configure(spec->port, spec->pin, GPIO_INPUT));
+		zassert_ok(gpio_keys_disable_interrupt(test_gpio_keys_dev), NULL);
+		k_sleep(K_MSEC(500));
+
+		/* Check interrupts are disabled */
+		gpio_keys_interrupt_called = 0;
+		zassert_ok(gpio_emul_input_set(spec->port, spec->pin, 0));
+		k_sleep(K_MSEC(1000));
+		zassert_ok(gpio_emul_input_set(spec->port, spec->pin, 1));
+		k_sleep(K_MSEC(1000));
+		zassert_equal(gpio_keys_interrupt_called, 0);
+
+		zassert_ok(
+			gpio_keys_enable_interrupt(test_gpio_keys_dev, test_gpio_keys_cb_handler),
+			NULL);
+		zassert_ok(gpio_emul_input_set(spec->port, spec->pin, 0));
+		k_sleep(K_MSEC(1000));
+
+		gpio_keys_interrupt_called = 0;
+		zassert_ok(gpio_emul_input_set(spec->port, spec->pin, 1));
+
+		/* Check interrupt doesn't prematurely fires */
+		k_sleep(K_MSEC(config->debounce_interval_ms / 2));
+		zassert_equal(gpio_keys_interrupt_called, 0);
+
+		/* Check interrupt fires after debounce interval */
+		k_sleep(K_MSEC(config->debounce_interval_ms));
+		zassert_equal(gpio_keys_interrupt_called, pin_cfg->zephyr_code);
+	}
+}
+
+#endif /* DT_NODE_EXISTS(DT_NODELABEL(voldown_button)) */