modules: Handle desired configurations

Handle desired configurations set in the shadow:
 - Add cddl schema for configurations set in the shadow
 - Add configuration channel that interested modules can subscribe to
 - Enable PWM and set RGB values according to the shadow configurations
 - Update trigger module to only use system workqueue, this is ok
   since we are not blocking the system workqueue for long periods of
   time and its simplifies the module quite a bit.
 - The trigger will only run as long as we are connected.

Missing:
 - Adopting gnss enable. This depends on GNSS being sent internally
   from the location module.

Signed-off-by: Simen S. Røstad <[email protected]>

app/prj.conf

@@ -6,6 +6,8 @@
 
 CONFIG_NCS_SAMPLES_DEFAULTS=y
 CONFIG_RESET_ON_FATAL_ERROR=y
+CONFIG_DK_LIBRARY=y
+CONFIG_PWM=y
 
 # Heap and stacks
 # Extended AT host/monitor stack/heap sizes since some nrf_cloud credentials are longer than 1024 bytes.
@@ -105,11 +107,6 @@ CONFIG_NRF_CLOUD_COAP_SEC_TAG=4242
 #Required if device is provisioned to nRF Cloud using attestation token
 #CONFIG_NRF_CLOUD_CLIENT_ID_SRC_INTERNAL_UUID=y
 
-CONFIG_SIMPLE_CONFIG=y
-CONFIG_DK_LIBRARY=y
-
-CONFIG_SIMPLE_CONFIG_LOG_LEVEL_DBG=y
-
 # needed for processing floats
 CONFIG_PICOLIBC=y
 CONFIG_FPU=y

app/src/common/message_channel.c

@@ -50,18 +50,18 @@ ZBUS_CHAN_DEFINE(FATAL_ERROR_CHAN,
 		 ZBUS_MSG_INIT(0)
 );
 
-ZBUS_CHAN_DEFINE(LED_CHAN,
-		 int,
+ZBUS_CHAN_DEFINE(CONFIG_CHAN,
+		 struct configuration,
 		 NULL,
 		 NULL,
-		 ZBUS_OBSERVERS(led),
+		 ZBUS_OBSERVERS(led, trigger),
 		 ZBUS_MSG_INIT(0)
 );
 
 ZBUS_CHAN_DEFINE(CLOUD_CHAN,
 		 enum cloud_status,
 		 NULL,
 		 NULL,
-		 ZBUS_OBSERVERS(fota, app, location),
+		 ZBUS_OBSERVERS(fota, app, location, trigger),
 		 CLOUD_DISCONNECTED
 );

app/src/common/message_channel.h

@@ -42,14 +42,23 @@ enum cloud_status {
 	CLOUD_DISCONNECTED,
 };
 
+struct configuration {
+	int led_red;
+	int led_green;
+	int led_blue;
+	bool gnss;
+	uint64_t update_interval;
+};
+
 ZBUS_CHAN_DECLARE(
 	TRIGGER_CHAN,
 	PAYLOAD_CHAN,
 	NETWORK_CHAN,
 	FATAL_ERROR_CHAN,
 	LED_CHAN,
 	CLOUD_CHAN,
-	FOTA_ONGOING_CHAN
+	FOTA_ONGOING_CHAN,
+	CONFIG_CHAN
 );
 
 #ifdef __cplusplus

app/src/modules/app/CMakeLists.txt

@@ -5,3 +5,30 @@
 #
 
 target_sources(app PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/app.c)
+
+# generate encoder code using zcbor
+set(zcbor_command
+	zcbor code # Invoke code generation
+	--cddl ${ZEPHYR_BASE}/subsys/net/lib/lwm2m/lwm2m_senml_cbor.cddl
+	--cddl ${CMAKE_CURRENT_SOURCE_DIR}/app_object.cddl
+	--decode # Generate decoding functions
+	--short-names # Attempt to make generated symbol names shorter (at the risk of collision)
+	-t app-object # Create a public API for decoding the "app_object" type from the cddl file
+	--output-cmake ${CMAKE_CURRENT_BINARY_DIR}/app_object.cmake # The generated cmake file will be placed here
+)
+execute_process(COMMAND ${zcbor_command} COMMAND_ERROR_IS_FATAL ANY)
+
+# Include the cmake file generated by zcbor. It adds the
+# generated code and the necessary zcbor C code files.
+include(${CMAKE_CURRENT_BINARY_DIR}/app_object.cmake)
+
+# Ensure that the cmake reconfiguration is triggerred everytime the cddl file changes.
+# This ensures that the codec generation is triggered.
+set_property(
+	DIRECTORY
+	PROPERTY
+	CMAKE_CONFIGURE_DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/app_object.cddl
+)
+
+zephyr_link_libraries(app_object)
+target_link_libraries(app_object PRIVATE zephyr_interface)

app/src/modules/app/Kconfig.app

@@ -6,7 +6,7 @@ menu "App"
 
 config APP_MODULE_THREAD_STACK_SIZE
 	int "Thread stack size"
-	default 4096
+	default 8192
 
 config APP_MODULE_MESSAGE_QUEUE_SIZE
 	int "Message queue size"

app/src/modules/app/app.c

@@ -7,10 +7,12 @@
 #include <zephyr/kernel.h>
 #include <zephyr/logging/log.h>
 #include <zephyr/zbus/zbus.h>
-#include <simple_config/simple_config.h>
 #include <zephyr/task_wdt/task_wdt.h>
+#include <net/nrf_cloud_coap.h>
+#include <nrf_cloud_coap_transport.h>
 
 #include "message_channel.h"
+#include "app_object_decode.h" /* change this to config object and add led object here */
 
 /* Register log module */
 LOG_MODULE_REGISTER(app, CONFIG_APP_LOG_LEVEL);
@@ -21,45 +23,86 @@ ZBUS_SUBSCRIBER_DEFINE(app, CONFIG_APP_MODULE_MESSAGE_QUEUE_SIZE);
 BUILD_ASSERT(CONFIG_APP_MODULE_WATCHDOG_TIMEOUT_SECONDS > CONFIG_APP_MODULE_EXEC_TIME_SECONDS_MAX,
 	     "Watchdog timeout must be greater than maximum execution time");
 
-int config_cb(const char *key, const struct simple_config_val *val)
+static void shadow_get(bool get_desired)
 {
 	int err;
-
-	if (val->type == SIMPLE_CONFIG_VAL_STRING) {
-		LOG_DBG("\"%s\" = %s", key, val->val._str);
-	} else if (val->type == SIMPLE_CONFIG_VAL_BOOL) {
-		LOG_DBG("\"%s\" = %s", key, val->val._bool ? "true" : "false");
-	} else if (val->type == SIMPLE_CONFIG_VAL_DOUBLE) {
-		LOG_DBG("\"%s\" = %f", key, val->val._double);
-	} else {
-		return -EINVAL;
+	struct app_object app_object = { 0 };
+	uint8_t buf_cbor[512] = { 0 };
+	uint8_t buf_json[512] = { 0 };
+	size_t buf_cbor_len = sizeof(buf_cbor);
+	size_t buf_json_len = sizeof(buf_json);
+	size_t not_used;
+
+	/* Request shadow delta, request only changes by setting delta parameter to true. */
+	err = nrf_cloud_coap_shadow_get(buf_json, &buf_json_len, !get_desired,
+					COAP_CONTENT_FORMAT_APP_JSON);
+	if (err == -EACCES) {
+		LOG_WRN("Not connected");
+		return;
+	} else if (err) {
+		LOG_ERR("Failed to request shadow delta: %d", err);
+		SEND_FATAL_ERROR();
+		return;
 	}
 
-	if (strcmp(key, "led_blue") == 0) {
-		int status = val->val._bool;
-
-		err = zbus_chan_pub(&LED_CHAN, &status, K_NO_WAIT);
-		if (err) {
-			LOG_ERR("zbus_chan_pub, error:%d", err);
-			SEND_FATAL_ERROR();
-			return err;
-		}
+	if (buf_json_len == 0 || strlen(buf_json) == 0) {
+		LOG_WRN("No shadow delta changes available");
+		return;
+	}
 
-		return 0;
+	/* Shadow available, fetch CBOR encoded desired section. */
+	err = nrf_cloud_coap_shadow_get(buf_cbor, &buf_cbor_len, false,
+					COAP_CONTENT_FORMAT_APP_CBOR);
+	if (err == -EACCES) {
+		LOG_WRN("Not connected");
+		return;
+	} else if (err) {
+		LOG_ERR("Failed to request shadow delta: %d", err);
+		SEND_FATAL_ERROR();
+		return;
 	}
 
-	return -EINVAL;
-}
+	err = cbor_decode_app_object(buf_cbor, buf_cbor_len, &app_object, &not_used);
+	if (err) {
+		LOG_ERR("Failed to decode app object, error: %d", err);
+		SEND_FATAL_ERROR();
+		return;
+	}
 
-static void init_app_settings(void)
-{
-	struct simple_config_val val = {.type = SIMPLE_CONFIG_VAL_BOOL, .val._bool = true};
-	int err = simple_config_set("blue_led", &val);
+	struct configuration configuration = {
+		.led_red = app_object.lwm2m._1424010._0._0,
+		.led_green = app_object.lwm2m._1424010._0._1,
+		.led_blue = app_object.lwm2m._1424010._0._2,
+		.gnss = app_object.lwm2m._1430110._0._1,
+		.update_interval = app_object.lwm2m._1430110._0._0,
+	};
+
+	LOG_DBG("LED object (1424010) values received from cloud:");
+	LOG_DBG("R: %d", app_object.lwm2m._1424010._0._0);
+	LOG_DBG("G: %d", app_object.lwm2m._1424010._0._1);
+	LOG_DBG("B: %d", app_object.lwm2m._1424010._0._2);
+	LOG_DBG("Timestamp: %lld", app_object.lwm2m._1424010._0._99);
+
+	LOG_DBG("Application configuration object (1430110) values received from cloud:");
+	LOG_DBG("Update interval: %lld", app_object.lwm2m._1430110._0._0);
+	LOG_DBG("GNSS: %d", app_object.lwm2m._1430110._0._1);
+	LOG_DBG("Timestamp: %lld", app_object.lwm2m._1430110._0._99);
+
+	/* Distribute configuration */
+	err = zbus_chan_pub(&CONFIG_CHAN, &configuration, K_SECONDS(1));
 	if (err) {
-		LOG_ERR("simple_config_set, error: %d", err);
+		LOG_ERR("zbus_chan_pub, error: %d", err);
 		SEND_FATAL_ERROR();
 		return;
 	}
+
+	/* Send the received configuration back to the reported shadow section. */
+	err = nrf_cloud_coap_shadow_state_update(buf_json);
+	if (err < 0) {
+		LOG_ERR("Failed to send PATCH request: %d", err);
+	} else if (err > 0) {
+		LOG_ERR("Error from server: %d", err);
+	}
 }
 
 static void task_wdt_callback(int channel_id, void *user_data)
@@ -84,12 +127,6 @@ static void app_task(void)
 
 	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);
-
-	/* Set initial settting values (can be skipped if cloud initializes shadow) */
-	init_app_settings();
-
 	while (true) {
 		err = task_wdt_feed(task_wdt_id);
 		if (err) {
@@ -118,19 +155,15 @@ static void app_task(void)
 			}
 
 			if (cloud_status == CLOUD_CONNECTED) {
-				LOG_INF("Cloud connected");
-				LOG_INF("Getting latest device configuration from cloud");
+				LOG_DBG("Cloud connected");
+				LOG_DBG("Getting latest device configuration from device shadow");
 
-				simple_config_update();
-			} else {
-				LOG_INF("Cloud disconnected");
+				shadow_get(true);
 			}
 		}
 
 		if ((&TRIGGER_CHAN == chan) && (cloud_status == CLOUD_CONNECTED)) {
-			LOG_INF("Getting latest device configuration from cloud");
-
-			simple_config_update();
+			shadow_get(false);
 		}
 	}
 }

app/src/modules/app/app_object.cddl

@@ -0,0 +1,41 @@
+; Define the basic structure of the JSON object
+app-object = {
+    "nrfcloud_mqtt_topic_prefix": tstr,
+    "pairing": pairing-type,
+    "lwm2m": lwm2m-map
+}
+
+; Define the pairing object with nested topics
+pairing-type = {
+    "state": tstr,
+    "topics": {
+        "d2c": tstr,
+        "c2d": tstr
+    }
+}
+
+lwm2m-map = {
+  "14240:1.0": led,
+  "14301:1.0": config
+}
+
+led = {
+  "0": lwm2m_inner_object_1
+}
+
+lwm2m_inner_object_1 = {
+  "0": int .size 4,
+  "1": int .size 4,
+  "2": int .size 4,
+  "99": int .size 8
+}
+
+config = {
+  "0": lwm2m_inner_object
+}
+
+lwm2m_inner_object = {
+  "0": int .size 8,
+  "1": bool,
+  "99": int .size 8
+}

app/src/modules/led/led.c

@@ -7,26 +7,73 @@
 #include <zephyr/kernel.h>
 #include <zephyr/logging/log.h>
 #include <zephyr/zbus/zbus.h>
+#include <zephyr/drivers/led.h>
+#include <zephyr/drivers/pwm.h>
 #include <dk_buttons_and_leds.h>
 
 #include "message_channel.h"
 
 /* Register log module */
 LOG_MODULE_REGISTER(led, CONFIG_APP_LED_LOG_LEVEL);
 
+#define PWM_LED0_NODE	DT_ALIAS(pwm_led0)
+#define PWM_LED1_NODE	DT_ALIAS(pwm_led1)
+#define PWM_LED2_NODE	DT_ALIAS(pwm_led2)
+
+#if DT_NODE_HAS_STATUS(PWM_LED0_NODE, okay)
+static const struct pwm_dt_spec led0 = PWM_DT_SPEC_GET(PWM_LED0_NODE);
+#else
+#error "Unsupported board: pwm-led 0 devicetree alias is not defined"
+#endif
+#if DT_NODE_HAS_STATUS(PWM_LED1_NODE, okay)
+static const struct pwm_dt_spec led1 = PWM_DT_SPEC_GET(PWM_LED1_NODE);
+#else
+#error "Unsupported board: pwm-led 1 devicetree alias is not defined"
+#endif
+#if DT_NODE_HAS_STATUS(PWM_LED2_NODE, okay)
+static const struct pwm_dt_spec led2 = PWM_DT_SPEC_GET(PWM_LED2_NODE);
+#else
+#error "Unsupported board: pwm-led 2 devicetree alias is not defined"
+#endif
+
+#define PWM_PERIOD	20000U
+#define LIGHTNESS_MAX	UINT8_MAX
+
 void led_callback(const struct zbus_channel *chan)
 {
 	int err;
-	const int *status;
 
-	if (&LED_CHAN == chan) {
-		/* Get LED status from channel. */
-		status = zbus_chan_const_msg(chan);
+	if (&CONFIG_CHAN == chan) {
+		/* Get LED configuration from channel. */
+
+		const struct configuration *config = zbus_chan_const_msg(chan);
+
+		LOG_DBG("LED configuration: red:%d, green:%d, blue:%d",
+			config->led_red, config->led_green, config->led_blue);
+
+		/* Red LED */
+		err = pwm_set_dt(&led0, PWM_USEC(PWM_PERIOD),
+				 PWM_USEC((PWM_PERIOD * config->led_red) / LIGHTNESS_MAX));
+		if (err) {
+			LOG_ERR("pwm_set_dt, error:%d", err);
+			SEND_FATAL_ERROR();
+			return;
+		}
 
 		/* Blue LED */
-		err = dk_set_led(DK_LED2, *status);
+		err = pwm_set_dt(&led1, PWM_USEC(PWM_PERIOD),
+				 PWM_USEC((PWM_PERIOD * config->led_blue) / LIGHTNESS_MAX));
+		if (err) {
+			LOG_ERR("pwm_set_dt, error:%d", err);
+			SEND_FATAL_ERROR();
+			return;
+		}
+
+		/* Green LED */
+		err = pwm_set_dt(&led2, PWM_USEC(PWM_PERIOD),
+				 PWM_USEC((PWM_PERIOD * config->led_green) / LIGHTNESS_MAX));
 		if (err) {
-			LOG_ERR("dk_set_led, error:%d", err);
+			LOG_ERR("pwm_set_dt, error:%d", err);
 			SEND_FATAL_ERROR();
 			return;
 		}