esp_netif: docs update to include tcpip_adapter migration guide

added migration guide link to the esp-netif page and network page
added redirects from tcpip_adapter to new esp_netif

docs/en/api-reference/network/esp_netif.rst

@@ -12,9 +12,11 @@ Some ESP-NETIF API functions are intended to be called by application code, for
 
 In many cases, applications do not need to call ESP-NETIF APIs directly as they are called from the default network event handlers.
 
+ESP-NETIF component is a successor of the tcpip_adapter, former network interface abstraction, which has become deprecated since IDF v4.1.
+Please refer to the :doc:`/api-reference/network/tcpip_adapter_migration` section in case existing applications to be ported to use the esp-netif API instead.
 
 ESP-NETIF architecture
-======================
+----------------------
 
 .. code-block:: text
 

docs/en/api-reference/network/index.rst

@@ -38,8 +38,16 @@ IP Network Layer
 
    ESP-NETIF <esp_netif.rst>
 
+.. toctree::
+    :hidden:
+
+    TCP/IP Adapter Migration Guide <tcpip_adapter_migration.rst>
+
 Code examples for TCP/IP socket APIs are provided in the :example:`protocols/sockets` directory of ESP-IDF examples.
 
+The TCP/IP Adapter (legacy network interface library) has been deprecated, please consult the :doc:`/api-reference/network/tcpip_adapter_migration`
+to update existing IDF applications.
+
 Application Layer 
 =================
 

docs/en/api-reference/network/tcpip_adapter_migration.rst

@@ -0,0 +1,83 @@
+TCP/IP Adapter Migration Guide
+==============================
+
+TCP/IP Adapter is a network interface abstraction component used in IDF prior to v4.1. This page outlines migration from tcpip_adapter API
+to its successor :doc:`/api-reference/network/esp_netif`.
+
+
+Updating network connection code
+--------------------------------
+
+
+Network stack initialization
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Simply replace ``tcpip_adapter_init()`` with ``esp_netif_init()``. Please note that the :doc:`/api-reference/network/esp_netif` initialization API returns standard error code and the ``esp_netif_deinit()``
+for un-initialization is available.
+
+Also replace ``#include "tcpip_adapter.h"`` with ``#include "esp_netif.h"``.
+
+
+Network interface creation
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+TCP/IP Adapter defined these three interfaces statically:
+
+- WiFi Station
+- WiFi Access Point
+- Ethernet
+
+Network interface instance shall be explicitly constructed for the :doc:`/api-reference/network/esp_netif` to enable its connection to the TCP/IP stack.
+For example initialization code for WiFi has to explicitly call ``esp_netif_create_default_wifi_sta();`` or ``esp_netif_create_default_wifi_ap();`` after the TCP/IP stack and the event loop
+have been initialized.
+Please consult an example initialization code for these three interfaces:
+
+- WiFi Station: :example:`examples/wifi/getting_started/station/main/station_example_main.c`
+- WiFi Access Point: :example:`examples/wifi/getting_started/softAP/main/softap_example_main.c`
+- Ethernet :example:`examples/ethernet/basic/main/ethernet_example_main.c`
+
+
+Replacing other tcpip_adapter API
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+All the tcpip_adapter functions have their esp-netif counter-part. Please refer to the esp_netif.h grouped into these sections:
+
+*  :component_file:`Setters/Getters <esp_netif/include/esp_netif.h#L241>`
+*  :component_file:`DHCP <esp_netif/include/esp_netif.h#L387>`
+*  :component_file:`DNS <esp_netif/include/esp_netif.h#L516>`
+*  :component_file:`IP address <esp_netif/include/esp_netif.h#L568>`
+
+
+Default event handlers
+^^^^^^^^^^^^^^^^^^^^^^
+
+Event handlers are moved from tcpip_adapter to appropriate driver code. There is no change from application code perspective, all events shall be handled in the same way.
+Please note that within IP related event handlers, application code usually receives IP addresses in a form of esp-netif specific struct (not the lwIP structs, but binary compatible).
+This is the preferred way of printing the address:
+
+.. code-block:: c
+
+           ESP_LOGI(TAG, "got ip:" IPSTR "\n", IP2STR(&event->ip_info.ip));
+
+Instead of
+
+.. code-block:: c
+
+           ESP_LOGI(TAG, "got ip:%s\n", ip4addr_ntoa(&event->ip_info.ip));
+
+Since ``ip4addr_ntoa()`` is a lwIP API, the esp-netif provides ``esp_ip4addr_ntoa()`` as a replacement, but the above method is generally preferred.
+
+
+IP addresses
+^^^^^^^^^^^^
+
+It is preferred to use esp-netif defined IP structures. Please note that the lwIP structs will still work when default compatibility enabled.
+*  :component_file:`esp-netif IP address definitions <esp_netif/include/esp_netif_ip_addr.h#L96>`
+
+
+Next steps
+^^^^^^^^^^
+
+Additional step in porting an application to fully benefit from the :doc:`/api-reference/network/esp_netif` is to disable the tcpip_adapter compatibility layer in the component configuration:
+``ESP NETIF Adapter`` -> ``Enable backward compatible tcpip_adapter interface`` and check if the project compiles.
+TCP/IP adapter brings many include dependencies and this step might help in decoupling the application from using specific TCP/IP stack API directly.

docs/page_redirects.txt

@@ -14,7 +14,7 @@ api-reference/wifi/index                  api-reference/network/index
 api-reference/wifi/esp_now                api-reference/network/esp_now
 api-reference/wifi/esp_smartconfig        api-reference/network/esp_smartconfig
 api-reference/wifi/esp_wifi               api-reference/network/esp_wifi
-api-reference/system/tcpip_adapter        api-reference/network/tcpip_adapter
+api-reference/system/tcpip_adapter        api-reference/network/esp_netif
 get-started/idf-monitor                   api-guides/tools/idf-monitor
 get-started-cmake/idf-monitor             api-guides/tools/idf-monitor
 get-started/get-started-devkitc           hw-reference/get-started-devkitc
@@ -50,3 +50,4 @@ api-guide/build-system-cmake                   api-guide/build-system
 api-guide/ulp-cmake                            api-guide/ulp
 api-guide/unit-tests-cmake                     api-guide/unit-tests
 
+api-reference/network/tcpip_adapter            api-reference/network/esp_netif

docs/zh_CN/api-reference/network/index.rst

@@ -37,6 +37,7 @@ IP 网络层协议
    :maxdepth: 1
 
    ESP-NETIF <esp_netif.rst>
+   TCP/IP Adapter Migration Guide <tcpip_adapter_migration.rst>
 
 TCP/IP 套接字 API 的示例代码存放在 ESP-IDF 示例项目的 :example:`protocols/sockets` 目录下。
 

docs/zh_CN/api-reference/network/tcpip_adapter_migration.rst

@@ -0,0 +1 @@
+.. include:: ../../../en/api-reference/network/tcpip_adapter_migration.rst