diff --git a/src/datamodel.c b/src/datamodel.c
index f1e0c5c7c5838987915dcdefe7310de290b8613d..be99ac01a79665b8f70b4712c109b3ba44ba38cf 100644
--- a/src/datamodel.c
+++ b/src/datamodel.c
@@ -218,7 +218,7 @@ static int get_SoftwareModulesExecEnv_Alias(char *refparam, struct dmctx *ctx, v
 
 static int set_SoftwareModulesExecEnv_Alias(char *refparam, struct dmctx *ctx, void *data, char *instance, char *value, int action)
 {
-	char *ee_name;
+	char *ee_name = NULL;
 
 	switch (action)	{
 		case VALUECHECK:
@@ -228,6 +228,9 @@ static int set_SoftwareModulesExecEnv_Alias(char *refparam, struct dmctx *ctx, v
 		case VALUESET:
 			ee_name = dmjson_get_value((json_object *)data, 1, "ee_name");
 
+			if (DM_STRLEN(ee_name) == 0)
+				return 0;
+
 			dmubus_call_set("swmodules", "set_config", UBUS_ARGS{
 					{"ee_name", ee_name, String},
 					{"parameter", "ee_alias", String},
@@ -399,7 +402,7 @@ static int get_SoftwareModulesDeploymentUnit_Alias(char *refparam, struct dmctx
 
 static int set_SoftwareModulesDeploymentUnit_Alias(char *refparam, struct dmctx *ctx, void *data, char *instance, char *value, int action)
 {
-	char *ee_name, *uuid = NULL;
+	char *ee_name = NULL, *uuid = NULL;
 
 	switch (action)	{
 		case VALUECHECK:
@@ -410,13 +413,8 @@ static int set_SoftwareModulesDeploymentUnit_Alias(char *refparam, struct dmctx
 			ee_name = dmjson_get_value((json_object *)data, 1, "ee_name");
 			uuid = dmjson_get_value((json_object *)data, 1, "uuid");
 
-			if (ee_name == NULL || uuid == NULL) {
-				return 0;
-			}
-
-			if (ee_name[0] == '\0' || uuid[0] == '\0') {
+			if (DM_STRLEN(ee_name) == 0 || DM_STRLEN(uuid) == 0)
 				return 0;
-			}
 
 			dmubus_call_set("swmodules", "set_config", UBUS_ARGS{
 					{"ee_name", ee_name, String},
@@ -597,13 +595,8 @@ static int set_SoftwareModulesExecutionUnit_Alias(char *refparam, struct dmctx *
 			eu_name = dmjson_get_value((json_object *)data, 1, "eu_name");
 			eu_env = dmjson_get_value((json_object *)data, 1, "ee_name");
 
-			if (eu_name == NULL || eu_env == NULL) {
+			if (DM_STRLEN(eu_name) == 0 || DM_STRLEN(eu_env) == 0)
 				return 0;
-			}
-
-			if (eu_name[0] == '\0' || eu_env[0] == '\0') {
-				return 0;
-			}
 
 			dmubus_call_set("swmodules", "set_config", UBUS_ARGS{
 					{"ee_name", eu_env, String},
@@ -814,12 +807,12 @@ static int get_SoftwareModulesExecutionUnit_ExecutionEnvRef(char *refparam, stru
  *************************************************************/
 static int operate_SoftwareModulesExecEnv_Reset(char *refparam, struct dmctx *ctx, void *data, char *instance, char *value, int action)
 {
-	return CMD_FAIL;
+	return USP_FAULT_COMMAND_FAILURE;
 }
 
 static int operate_SoftwareModulesExecEnv_SetRunLevel(char *refparam, struct dmctx *ctx, void *data, char *instance, char *value, int action)
 {
-	return CMD_FAIL;
+	return USP_FAULT_COMMAND_FAILURE;
 }
 
 static operation_args softwaremodules_installdu_args = {
@@ -846,7 +839,7 @@ static int operate_SoftwareModules_InstallDU(char *refparam, struct dmctx *ctx,
 
 	char *url = dmjson_get_value((json_object *)value, 1, "URL");
 	if (url[0] == '\0')
-		return CMD_INVALID_ARGUMENTS;
+		return USP_FAULT_INVALID_ARGUMENT;
 
 	char *uuid = dmjson_get_value((json_object *)value, 1, "UUID");
 	char *username = dmjson_get_value((json_object *)value, 1, "Username");
@@ -859,7 +852,7 @@ static int operate_SoftwareModules_InstallDU(char *refparam, struct dmctx *ctx,
 	}
 
 	if (eeid == 0)
-		return CMD_FAIL;
+		return USP_FAULT_COMMAND_FAILURE;
 
 	char eeid_str[16] = {0};
 	snprintf(eeid_str, sizeof(eeid_str), "%u", eeid);
@@ -874,7 +867,7 @@ static int operate_SoftwareModules_InstallDU(char *refparam, struct dmctx *ctx,
 			&res);
 
 	char *status = dmjson_get_value(res, 1, "status");
-	return (strcmp(status, "true") == 0) ? CMD_SUCCESS : CMD_FAIL;
+	return (strcmp(status, "true") == 0) ? 0 : USP_FAULT_COMMAND_FAILURE;
 }
 
 static operation_args softwaremodulesdeploymentunit_update_args = {
@@ -899,14 +892,14 @@ int operate_SoftwareModulesDeploymentUnit_Update(char *refparam, struct dmctx *c
 
 	char *url = dmjson_get_value((json_object *)value, 1, "URL");
 	if (url[0] == '\0')
-		return CMD_INVALID_ARGUMENTS;
+		return USP_FAULT_INVALID_ARGUMENT;
 
 	char *username = dmjson_get_value((json_object *)value, 1, "Username");
 	char *password = dmjson_get_value((json_object *)value, 1, "Password");
 
 	char *du_uuid = dmjson_get_value((json_object *)data, 1, "uuid");
 	if (!du_uuid || du_uuid[0] == '\0')
-		return CMD_FAIL;
+		return USP_FAULT_COMMAND_FAILURE;
 
 	// Find the uuid in config
 	uci_foreach_sections_safe("swmodd", "du_eu_assoc", stmp, s) {
@@ -919,7 +912,7 @@ int operate_SoftwareModulesDeploymentUnit_Update(char *refparam, struct dmctx *c
 	}
 
 	if (found == false)
-		return CMD_FAIL;
+		return USP_FAULT_COMMAND_FAILURE;
 
 	dmuci_set_value_by_section(s, "new_url", url);
 	dmuci_set_value_by_section(s, "username", username);
@@ -945,7 +938,7 @@ static int operate_SoftwareModulesDeploymentUnit_Uninstall(char *refparam, struc
 
 	char *status = dmjson_get_value(res, 1, "status");
 
-	return (strcmp(status, "true") == 0) ? CMD_SUCCESS : CMD_FAIL;
+	return (strcmp(status, "true") == 0) ? 0 : USP_FAULT_COMMAND_FAILURE;
 }
 
 static operation_args softwaremodulesexecutionunit_setrequestedstate_args = {
@@ -965,13 +958,13 @@ static int operate_SoftwareModulesExecutionUnit_SetRequestedState(char *refparam
 {
 	char *req_state = dmjson_get_value((json_object *)value, 1, "RequestedState");
 	if (strcmp(req_state, "Idle") != 0 && strcmp(req_state, "Active") != 0)
-		return CMD_INVALID_ARGUMENTS;
+		return USP_FAULT_INVALID_ARGUMENT;
 
 	char *eid = dmjson_get_value((json_object *)data, 1, "eeid");
 	char *name = dmjson_get_value((json_object *)data, 1, "eu_name");
 
 	if (!eid || !name) {
-		return CMD_FAIL;
+		return USP_FAULT_COMMAND_FAILURE;
 	}
 
 	dmubus_call_set("swmodules", "set_config", UBUS_ARGS{
@@ -981,7 +974,7 @@ static int operate_SoftwareModulesExecutionUnit_SetRequestedState(char *refparam
 			{"value", req_state, String}},
 			4);
 
-	return CMD_SUCCESS;
+	return 0;
 }
 
 /*************************************************************