modules: app: Use task watchdog

Use task watchdog. This will reset the device if the application task is blocked for a configurable amount of time. and, minor cleanup. Signed-off-by: Simen S. Røstad <[email protected]> Signed-off-by: Balaji Srinivasan <[email protected]>
hello-nrfcloud · May 29, 2024 · f3fd774 · f3fd774
1 parent 042e06c
commit f3fd774
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Showing 4 changed files with 73 additions and 36 deletions.
diff --git a/app/prj.conf b/app/prj.conf
@@ -212,3 +212,6 @@ CONFIG_APP_LOG_LEVEL_DBG=y
 # Fuel Gage
 CONFIG_NRF_FUEL_GAUGE=y
 CONFIG_NPM1300_CHARGER=y
+
+# Task Watchdog
+CONFIG_TASK_WDT=y
diff --git a/app/src/common/message_channel.h b/app/src/common/message_channel.h
@@ -34,12 +34,12 @@ struct payload {
 };
 
 enum network_status {
-	NETWORK_DISCONNECTED,
+	NETWORK_DISCONNECTED = 0x1,
 	NETWORK_CONNECTED,
 };
 
 enum cloud_status {
-	CLOUD_CONNECTED,
+	CLOUD_CONNECTED = 0x1,
 	CLOUD_DISCONNECTED,
 };
 

diff --git a/app/src/modules/app/Kconfig.app b/app/src/modules/app/Kconfig.app
@@ -14,4 +14,8 @@ config APP_MODULE_MESSAGE_QUEUE_SIZE
 	help
 	  ZBus subscriber message queue size.
 
+config APP_MODULE_WATCDHOG_TIMEOUT_SECONDS
+	int "Watchdog timeout seconds"
+	default 60
+
 endmenu
diff --git a/app/src/modules/app/app.c b/app/src/modules/app/app.c
@@ -8,6 +8,7 @@
 #include <zephyr/logging/log.h>
 #include <zephyr/zbus/zbus.h>
 #include <simple_config/simple_config.h>
+#include <zephyr/task_wdt/task_wdt.h>
 
 #include "message_channel.h"
 
@@ -48,18 +49,6 @@ int config_cb(const char *key, const struct simple_config_val *val)
 	return -EINVAL;
 }
 
-static bool check_cloud_connection(void)
-{
-	enum cloud_status cloud_status;
-	int err = zbus_chan_read(&CLOUD_CHAN, &cloud_status, K_FOREVER);
-
-	if (err) {
-		LOG_ERR("zbus_chan_read, error: %d", err);
-		SEND_FATAL_ERROR();
-	}
-	return cloud_status == CLOUD_CONNECTED;
-}
-
 static void init_app_settings(void)
 {
 	struct simple_config_val val = {.type = SIMPLE_CONFIG_VAL_BOOL, .val._bool = true};
@@ -70,43 +59,75 @@ static void init_app_settings(void)
 	}
 }
 
-static void wait_for_cloud_connection(void)
+static void task_wdt_callback(int channel_id, void *user_data)
 {
-	const struct zbus_channel *chan;
+	LOG_ERR("Watchdog expired, Channel: %d, Thread: %s",
+		channel_id, k_thread_name_get((k_tid_t)user_data));
 
-	while (!zbus_sub_wait(&app, &chan, K_FOREVER)) {
-		if (&CLOUD_CHAN == chan) {
-			if (check_cloud_connection()) {
-				return;
-			}
-		}
-	}
+	SEND_FATAL_ERROR();
 }
 
 static void app_task(void)
 {
-	const struct zbus_channel *chan;
+	int err;
+	const struct zbus_channel *chan = NULL;
+	int task_wdt_id;
+	const uint32_t wdt_timeout_ms = CONFIG_APP_MODULE_WATCDHOG_TIMEOUT_SECONDS * MSEC_PER_SEC;
+	const k_timeout_t zbus_wait_ms = K_MSEC(wdt_timeout_ms - 100);
+	enum cloud_status cloud_status = 0;
+
+	LOG_DBG("Application module task started");
+
+	task_wdt_id = task_wdt_add(wdt_timeout_ms, task_wdt_callback, (void *)k_current_get());
 
 	/* Set up callback for runtime config changes from cloud */
 	simple_config_set_callback(config_cb);
 
-	/* Wait for cloud connection */
-	wait_for_cloud_connection();
-
 	/* Set initial settting values (can be skipped if cloud initializes shadow) */
 	init_app_settings();
 
-	/* Initial config update */
-	simple_config_update();
+	while (true) {
+		err = zbus_sub_wait(&app, &chan, zbus_wait_ms);
+		if (err && err != -EAGAIN) {
+			LOG_ERR("zbus_sub_wait, error: %d", err);
+			SEND_FATAL_ERROR();
+			return;
+		}
+
+		err = task_wdt_feed(task_wdt_id);
+		if (err) {
+			LOG_ERR("task_wdt_feed, error: %d", err);
+			SEND_FATAL_ERROR();
+			return;
+		}
+
+		if (err == -EAGAIN) {
+			continue;
+		}
+
+		if ((&CLOUD_CHAN == chan)) {
+			LOG_DBG("Cloud connection status received");
+
+			err = zbus_chan_read(&CLOUD_CHAN, &cloud_status, K_FOREVER);
+			if (err) {
+				LOG_ERR("zbus_chan_read, error: %d", err);
+				SEND_FATAL_ERROR();
+				return;
+			}
 
-	while (!zbus_sub_wait(&app, &chan, K_FOREVER)) {
-		if (&CLOUD_CHAN == chan) {
-			if (!check_cloud_connection()) {
-				wait_for_cloud_connection();
+			if (cloud_status == CLOUD_CONNECTED) {
+				LOG_INF("Cloud connected");
+				LOG_INF("Getting latest device configuration fron cloud");
+
+				simple_config_update();
+			} else {
+				LOG_INF("Cloud disconnected");
 			}
-		} else if (&TRIGGER_CHAN == chan) {
-			LOG_DBG("Trigger received");
-			/* handle incoming cloud settings */
+		}
+
+		if ((&TRIGGER_CHAN == chan) && (cloud_status == CLOUD_CONNECTED)) {
+			LOG_INF("Getting latest device configuration fron cloud");
+
 			simple_config_update();
 		}
 	}
@@ -115,3 +136,12 @@ static void app_task(void)
 K_THREAD_DEFINE(app_task_id,
 		CONFIG_APP_MODULE_THREAD_STACK_SIZE,
 		app_task, NULL, NULL, NULL, 3, 0, 0);
+
+static int watchdog_init(void)
+{
+	__ASSERT((task_wdt_init(NULL) == 0), "Task watchdog init failure");
+
+	return 0;
+}
+
+SYS_INIT(watchdog_init, POST_KERNEL, CONFIG_APPLICATION_INIT_PRIORITY);