samples: subsys: display: lvgl: Add button to reset counter

Connect the sw0 alias to reset the counter.

Signed-off-by: Pieter De Gendt <[email protected]>

Author: pdgendt

samples/subsys/display/lvgl/src/main.c

@@ -5,7 +5,9 @@
  */
 
 #include <zephyr/device.h>
+#include <zephyr/devicetree.h>
 #include <zephyr/drivers/display.h>
+#include <zephyr/drivers/gpio.h>
 #include <lvgl.h>
 #include <stdio.h>
 #include <string.h>
@@ -15,9 +17,28 @@
 #include <zephyr/logging/log.h>
 LOG_MODULE_REGISTER(app);
 
+static uint32_t count;
+
+#ifdef CONFIG_GPIO
+static struct gpio_dt_spec button_gpio = GPIO_DT_SPEC_GET_OR(
+		DT_ALIAS(sw0), gpios, {0});
+static struct gpio_callback button_callback;
+
+static void button_isr_callback(const struct device *port,
+				struct gpio_callback *cb,
+				uint32_t pins)
+{
+	ARG_UNUSED(port);
+	ARG_UNUSED(cb);
+	ARG_UNUSED(pins);
+
+	count = 0;
+}
+#endif
+
 void main(void)
 {
-	uint32_t count = 0U;
+	int err;
 	char count_str[11] = {0};
 	const struct device *display_dev;
 	lv_obj_t *hello_world_label;
@@ -29,6 +50,32 @@ void main(void)
 		return;
 	}
 
+#ifdef CONFIG_GPIO
+	if (device_is_ready(button_gpio.port)) {
+		err = gpio_pin_configure_dt(&button_gpio, GPIO_INPUT);
+		if (err) {
+			LOG_ERR("failed to configure button gpio: %d", err);
+			return;
+		}
+
+		gpio_init_callback(&button_callback, button_isr_callback,
+				   BIT(button_gpio.pin));
+
+		err = gpio_add_callback(button_gpio.port, &button_callback);
+		if (err) {
+			LOG_ERR("failed to add button callback: %d", err);
+			return;
+		}
+
+		err = gpio_pin_interrupt_configure_dt(&button_gpio,
+						      GPIO_INT_EDGE_TO_ACTIVE);
+		if (err) {
+			LOG_ERR("failed to enable button callback: %d", err);
+			return;
+		}
+	}
+#endif
+
 	if (IS_ENABLED(CONFIG_LV_Z_POINTER_KSCAN)) {
 		lv_obj_t *hello_world_button;
 
@@ -54,7 +101,7 @@ void main(void)
 			lv_label_set_text(count_label, count_str);
 		}
 		lv_task_handler();
-		k_sleep(K_MSEC(10));
 		++count;
+		k_sleep(K_MSEC(10));
 	}
 }