[Thread] Fix linker errors when linking with OpenThread MTD (#3845)

- Add config variable CHIP_DEVICE_CONFIG_THREAD_FTD
  indicating if CHIP should use Full Thread Device features.
- On nrfconnect bind the variable to Kconfig variable
  CONFIG_OPENTHREAD_FTD.
- Fix ThreadStackManager build with FTD features disabled.

src/include/platform/CHIPDeviceConfig.h

@@ -532,6 +532,15 @@
 #define CHIP_DEVICE_CONFIG_ENABLE_THREAD 0
 #endif
 
+/**
+ * CHIP_DEVICE_CONFIG_THREAD_FTD
+ *
+ * Enable Full Thread Device features
+ */
+#ifndef CHIP_DEVICE_CONFIG_THREAD_FTD
+#define CHIP_DEVICE_CONFIG_THREAD_FTD 1
+#endif
+
 /**
  * CHIP_DEVICE_CONFIG_THREAD_TASK_NAME
  *

src/platform/OpenThread/GenericThreadStackManagerImpl_OpenThread.cpp

@@ -28,13 +28,17 @@
 
 #include <openthread/cli.h>
 #include <openthread/dataset.h>
-#include <openthread/dataset_ftd.h>
 #include <openthread/joiner.h>
 #include <openthread/link.h>
 #include <openthread/netdata.h>
 #include <openthread/tasklet.h>
 #include <openthread/thread.h>
+
+#if CHIP_DEVICE_CONFIG_THREAD_FTD
+#include <openthread/dataset_ftd.h>
 #include <openthread/thread_ftd.h>
+#endif
+
 #include <platform/OpenThread/GenericThreadStackManagerImpl_OpenThread.h>
 #include <platform/OpenThread/OpenThreadUtils.h>
 #include <platform/ThreadStackManager.h>
@@ -281,36 +285,24 @@ bool GenericThreadStackManagerImpl_OpenThread<ImplClass>::_IsThreadAttached(void
 template <class ImplClass>
 ConnectivityManager::ThreadDeviceType GenericThreadStackManagerImpl_OpenThread<ImplClass>::_GetThreadDeviceType(void)
 {
-    otLinkModeConfig linkMode;
     ConnectivityManager::ThreadDeviceType deviceType;
 
     Impl()->LockThreadStack();
 
-    linkMode = otThreadGetLinkMode(mOTInst);
+    const otLinkModeConfig linkMode = otThreadGetLinkMode(mOTInst);
 
+#if CHIP_DEVICE_CONFIG_THREAD_FTD
+    if (linkMode.mDeviceType && otThreadIsRouterEligible(mOTInst))
+        ExitNow(deviceType = ConnectivityManager::kThreadDeviceType_Router);
     if (linkMode.mDeviceType)
-    {
-        if (otThreadIsRouterEligible(mOTInst))
-        {
-            deviceType = ConnectivityManager::kThreadDeviceType_Router;
-        }
-        else
-        {
-            deviceType = ConnectivityManager::kThreadDeviceType_FullEndDevice;
-        }
-    }
-    else
-    {
-        if (linkMode.mRxOnWhenIdle)
-        {
-            deviceType = ConnectivityManager::kThreadDeviceType_MinimalEndDevice;
-        }
-        else
-        {
-            deviceType = ConnectivityManager::kThreadDeviceType_SleepyEndDevice;
-        }
-    }
+        ExitNow(deviceType = ConnectivityManager::kThreadDeviceType_FullEndDevice);
+#endif
+    if (linkMode.mRxOnWhenIdle)
+        ExitNow(deviceType = ConnectivityManager::kThreadDeviceType_MinimalEndDevice);
 
+    ExitNow(deviceType = ConnectivityManager::kThreadDeviceType_SleepyEndDevice);
+
+exit:
     Impl()->UnlockThreadStack();
 
     return deviceType;
@@ -323,11 +315,18 @@ GenericThreadStackManagerImpl_OpenThread<ImplClass>::_SetThreadDeviceType(Connec
     CHIP_ERROR err = CHIP_NO_ERROR;
     otLinkModeConfig linkMode;
 
-    VerifyOrExit(deviceType == ConnectivityManager::kThreadDeviceType_Router ||
-                     deviceType == ConnectivityManager::kThreadDeviceType_FullEndDevice ||
-                     deviceType == ConnectivityManager::kThreadDeviceType_MinimalEndDevice ||
-                     deviceType == ConnectivityManager::kThreadDeviceType_SleepyEndDevice,
-                 err = CHIP_ERROR_INVALID_ARGUMENT);
+    switch (deviceType)
+    {
+#if CHIP_DEVICE_CONFIG_THREAD_FTD
+    case ConnectivityManager::kThreadDeviceType_Router:
+    case ConnectivityManager::kThreadDeviceType_FullEndDevice:
+#endif
+    case ConnectivityManager::kThreadDeviceType_MinimalEndDevice:
+    case ConnectivityManager::kThreadDeviceType_SleepyEndDevice:
+        break;
+    default:
+        ExitNow(err = CHIP_ERROR_INVALID_ARGUMENT);
+    }
 
 #if CHIP_PROGRESS_LOGGING
 
@@ -362,12 +361,14 @@ GenericThreadStackManagerImpl_OpenThread<ImplClass>::_SetThreadDeviceType(Connec
 
     switch (deviceType)
     {
+#if CHIP_DEVICE_CONFIG_THREAD_FTD
     case ConnectivityManager::kThreadDeviceType_Router:
     case ConnectivityManager::kThreadDeviceType_FullEndDevice:
         linkMode.mDeviceType   = true;
         linkMode.mRxOnWhenIdle = true;
         otThreadSetRouterEligible(mOTInst, deviceType == ConnectivityManager::kThreadDeviceType_Router);
         break;
+#endif
     case ConnectivityManager::kThreadDeviceType_MinimalEndDevice:
         linkMode.mDeviceType   = false;
         linkMode.mRxOnWhenIdle = true;
@@ -607,8 +608,9 @@ CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_GetAndLogThread
 #define TELEM_NEIGHBOR_TABLE_SIZE (64)
 #define TELEM_PRINT_BUFFER_SIZE (64)
 
+#if CHIP_DEVICE_CONFIG_THREAD_FTD
 template <class ImplClass>
-CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_GetAndLogThreadTopologyFull(void)
+CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_GetAndLogThreadTopologyFull()
 {
     CHIP_ERROR err = CHIP_NO_ERROR;
     otError otErr;
@@ -762,6 +764,13 @@ CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_GetAndLogThread
     }
     return err;
 }
+#else // CHIP_DEVICE_CONFIG_THREAD_FTD
+template <class ImplClass>
+CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_GetAndLogThreadTopologyFull()
+{
+    return CHIP_ERROR_UNSUPPORTED_CHIP_FEATURE;
+}
+#endif
 
 template <class ImplClass>
 CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_GetPrimary802154MACAddress(uint8_t * buf)

src/platform/nrfconnect/CHIPDevicePlatformConfig.h

@@ -31,6 +31,7 @@
 #define CHIP_DEVICE_CONFIG_ENABLE_WIFI_AP 0
 
 #define CHIP_DEVICE_CONFIG_ENABLE_THREAD CONFIG_NET_L2_OPENTHREAD
+#define CHIP_DEVICE_CONFIG_THREAD_FTD CONFIG_OPENTHREAD_FTD
 
 #define CHIP_DEVICE_CONFIG_ENABLE_CHIPOBLE CONFIG_BT