Merge pull request #941 from gabsuren/ws_bump_1.6.0

bump(websocket): 1.5.0 -> 1.6.0

.github/workflows/eppp__build.yml

@@ -13,7 +13,7 @@ jobs:
     name: Build
     strategy:
       matrix:
-        idf_ver: ["latest", "release-v5.3"]
+        idf_ver: ["latest", "release-v5.5", "release-v5.4", "release-v5.3"]
         test: [ { app: host, path: "examples/host" }, { app: slave, path: "examples/slave" }, { app: test_app, path: "test/test_app" }]
     runs-on: ubuntu-22.04
     container: espressif/idf:${{ matrix.idf_ver }}
@@ -21,6 +21,8 @@ jobs:
       - name: Checkout esp-protocols
         uses: actions/checkout@v3
       - name: Build ${{ matrix.test.app }} with IDF-${{ matrix.idf_ver }}
+        env:
+          EXPECTED_WARNING: "DeprecationWarning: 'MultiCommand' is deprecated and will be removed\nCryptographyDeprecationWarning: Parsed a serial number which wasn't positive"
         shell: bash
         run: |
           . ${IDF_PATH}/export.sh

.github/workflows/esp_dns__build.yml

@@ -33,6 +33,9 @@ jobs:
         shell: bash
         working-directory: ${{matrix.test.path}}
         run: |
+          if [[ "${{ matrix.idf_ver }}" == "release-v5.3" || "${{ matrix.idf_ver }}" == "release-v5.4" ]]; then
+            export EXPECTED_WARNING="unknown kconfig symbol 'LWIP_USE_ESP_GETADDRINFO'"
+          fi
           . ${IDF_PATH}/export.sh
           pip install idf-component-manager idf-build-apps --upgrade
           python ../../../ci/build_apps.py ./${{ matrix.test.app }} --target ${{ matrix.idf_target }} -vv --preserve-all --pytest-app

.github/workflows/examples_build-host-test.yml

@@ -59,10 +59,11 @@ jobs:
       - name: Build with IDF-${{ matrix.idf_ver }}
         shell: bash
         run: |
+          . ${GITHUB_WORKSPACE}/ci/config_env.sh
           . ${IDF_PATH}/export.sh
           python -m pip install idf-build-apps
-          python ./ci/build_apps.py examples/mqtt -l -t linux
-          timeout 5 ./examples/mqtt/build_linux_default/esp_mqtt_demo.elf | tee test.log  || true
+          python ./ci/build_apps.py examples/mqtt -l -t linux -r 'sdkconfig.ci'
+          timeout 5 ./examples/mqtt/build_linux/esp_mqtt_demo.elf | tee test.log  || true
           grep 'MQTT_EVENT_DATA' test.log
 
   run_on_target:

.github/workflows/mdns__build-target-test.yml

@@ -24,6 +24,11 @@ jobs:
         shell: bash
         run: |
           . ${IDF_PATH}/export.sh
+          if [[ "${{ matrix.idf_ver }}" == "latest" ]]; then
+            export EXPECTED_WARNING="warning: unknown kconfig symbol 'EXAMPLE_ETH_PHY_IP101'"
+          else
+            export EXPECTED_WARNING="warning: unknown kconfig symbol 'EXAMPLE_ETH_PHY_GENERIC'"
+          fi
           python -m pip install idf-build-apps
           # Build default configs for all targets
           python ./ci/build_apps.py components/mdns/${{ matrix.test.path }} -r default -d
@@ -71,6 +76,22 @@ jobs:
       - name: Run ${{ matrix.test.app }} application on ${{ matrix.idf_target }}
         working-directory: components/mdns/${{ matrix.test.path }}
         run: |
+            export PYENV_ROOT="$HOME/.pyenv"
+            export PATH="$PYENV_ROOT/bin:$PATH"
+            eval "$(pyenv init --path)"
+            eval "$(pyenv init -)"
+            if ! pyenv versions --bare | grep -q '^3\.12\.6$'; then
+              echo "Installing Python 3.12.6..."
+              pyenv install -s 3.12.6
+            fi
+            if ! pyenv virtualenvs --bare | grep -q '^myenv$'; then
+              echo "Creating pyenv virtualenv 'myenv'..."
+              pyenv virtualenv 3.12.6 myenv
+            fi
+            pyenv activate myenv
+            python --version
+            pip install --prefer-binary cryptography pytest-embedded pytest-embedded-serial-esp pytest-embedded-idf pytest-custom_exit_code esptool
+            pip install --extra-index-url https://dl.espressif.com/pypi/ -r $GITHUB_WORKSPACE/ci/requirements.txt
             unzip ci/artifacts.zip -d ci
             for dir in `ls -d ci/build_*`; do
             rm -rf build sdkconfig.defaults

.github/workflows/mdns__host-tests.yml

@@ -24,7 +24,7 @@ jobs:
         shell: bash
         run: |
           . ${IDF_PATH}/export.sh
-          python -m pip install idf-build-apps dnspython pytest pytest-embedded pytest-embedded-serial-esp pytest-embedded-idf
+          python -m pip install idf-build-apps==2.10.0 dnspython pytest pytest-embedded pytest-embedded-serial-esp pytest-embedded-idf
           cd $GITHUB_WORKSPACE/protocols
           # Build host tests app (with all configs and targets supported)
           python ./ci/build_apps.py components/mdns/tests/host_test/
@@ -68,3 +68,43 @@ jobs:
             diff -q $file /tmp/$file || exit 1
             echo "OK"
           done
+
+  fuzz_test:
+    if: contains(github.event.pull_request.labels.*.name, 'mdns-fuzz') || github.event_name == 'push'
+    name: Fuzzer tests for mdns lib
+    strategy:
+      matrix:
+        idf_ver: ["latest"]
+
+    runs-on: ubuntu-22.04
+    container: aflplusplus/aflplusplus
+    steps:
+      - name: Checkout esp-protocols
+        uses: actions/checkout@v4
+
+      - name: Checkout ESP-IDF
+        uses: actions/checkout@v4
+        with:
+          repository: espressif/esp-idf
+          path: idf
+          submodules: recursive
+
+      - name: Install Necessary Libs
+        run: |
+          apt-get update -y
+          apt-get install -y libbsd-dev
+
+      - name: Run AFL++
+        shell: bash
+        run: |
+          export IDF_PATH=$GITHUB_WORKSPACE/idf
+          cd components/mdns/tests/test_afl_fuzz_host/
+          make fuzz
+
+      - name: Upload Crash Artifacts
+        if: failure()
+        uses: actions/upload-artifact@v4
+        with:
+          name: fuzz-crashes
+          path: components/mdns/tests/test_afl_fuzz_host/out/default/crashes.tar.gz
+          if-no-files-found: ignore

.github/workflows/modem__build-host-tests.yml

@@ -15,11 +15,6 @@ jobs:
       matrix:
         idf_ver: ["latest", "release-v5.0", "release-v5.1", "release-v5.2", "release-v5.3", "release-v5.4"]
         example: ["pppos_client", "modem_console", "modem_tcp_client", "ap_to_pppos", "simple_cmux_client"]
-        include:
-          - idf_ver: "release-v5.0"
-            example: "simple_cmux_client"
-            warning: "Warning: The smallest app partition is nearly full"
-
     runs-on: ubuntu-22.04
     container: espressif/idf:${{ matrix.idf_ver }}
     steps:
@@ -30,9 +25,9 @@ jobs:
       - if: ${{ matrix.skip_config }}
         run: rm -f $GITHUB_WORKSPACE/protocols/components/esp_modem/examples/${{ matrix.example }}/sdkconfig.ci.${{ matrix.skip_config }}*
       - name: Build ${{ matrix.example }} with IDF-${{ matrix.idf_ver }}
-        env:
-          EXPECTED_WARNING: ${{ matrix.warning }}
         shell: bash
+        env:
+          EXPECTED_WARNING: "Warning: The smallest app partition is nearly full\nwarning: unknown kconfig symbol 'ESP32_PANIC_PRINT_HALT'"
         run: |
           . ${IDF_PATH}/export.sh
           python -m pip install idf-build-apps
@@ -45,7 +40,7 @@ jobs:
     strategy:
       matrix:
         idf_ver: ["release-v5.0", "release-v5.1", "release-v5.2", "release-v5.3", "release-v5.4", "latest"]
-        test: ["target", "target_ota", "target_iperf"]
+        test: ["target", "target_ota", "target_iperf", "target_urc"]
 
     runs-on: ubuntu-22.04
     container: espressif/idf:${{ matrix.idf_ver }}

.github/workflows/modem__target-test.yml

@@ -34,18 +34,16 @@ jobs:
           IDF_TARGET: ${{ matrix.idf_target }}
           SDKCONFIG: sdkconfig.ci.${{ matrix.test.app }}
         shell: bash
-        working-directory: ${{ env.TEST_DIR }}
         run: |
+          . ${GITHUB_WORKSPACE}/ci/config_env.sh
           . ${IDF_PATH}/export.sh
-          rm -rf sdkconfig build
-          [ -f ${SDKCONFIG} ] && cp ${SDKCONFIG} sdkconfig.defaults
-          idf.py set-target ${{ matrix.idf_target }}
-          idf.py build
-          $GITHUB_WORKSPACE/ci/clean_build_artifacts.sh ${GITHUB_WORKSPACE}/${TEST_DIR}/build
+          python -m pip install idf-build-apps
+          python ./ci/build_apps.py ${{ env.TEST_DIR }} -t ${{ matrix.idf_target }} -r 'sdkconfig.ci.${{ matrix.test.app }}'
+          $GITHUB_WORKSPACE/ci/clean_build_artifacts.sh ${GITHUB_WORKSPACE}/${TEST_DIR}/build_${{ matrix.idf_target }}
       - uses: actions/upload-artifact@v4
         with:
           name: modem_target_bin_${{ matrix.idf_target }}_${{ matrix.idf_ver }}_${{ matrix.test.app }}
-          path: ${{ env.TEST_DIR }}/build
+          path: ${{ env.TEST_DIR }}/build_${{ matrix.idf_target }}
           if-no-files-found: error
 
   target_tests_esp_modem:

.github/workflows/modem_sim__build.yml

@@ -0,0 +1,32 @@
+name: "modem_sim: build-tests"
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    types: [opened, synchronize, reopened, labeled]
+
+jobs:
+  build_modem_sim:
+    if: contains(github.event.pull_request.labels.*.name, 'modem_sim') || github.event_name == 'push'
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout esp-protocols
+        uses: actions/checkout@v3
+      - name: Checkout idf
+        uses: actions/checkout@v3
+        with:
+          repository: espressif/esp-idf
+          ref: 8ad0d3d8f2faab752635bee36070313c47c07a13
+          path: idf
+      - name: Build ESP-AT with IDF-${{ matrix.idf_ver }}
+        shell: bash
+        run: |
+          export IDF_PATH=$GITHUB_WORKSPACE/idf
+          ${IDF_PATH}/install.sh
+          cd common_components/modem_sim
+          ./install.sh
+          source export.sh
+          idf.py build

.github/workflows/mosq__build.yml

@@ -13,11 +13,19 @@ jobs:
     name: Mosquitto build
     strategy:
       matrix:
-        idf_ver: ["latest", "release-v5.3"]
+        idf_ver: ["latest", "release-v5.5", "release-v5.4", "release-v5.3", "release-v5.2", "release-v5.1"]
+        example: ["broker", "serverless_mqtt"]
+        exclude:
+          # serverless_mqtt is not supported on v5.1 and master (esp-peer dependency)
+          - idf_ver: "release-v5.1"
+            example: "serverless_mqtt"
+          - idf_ver: "latest"
+            example: "serverless_mqtt"
+
     runs-on: ubuntu-22.04
     container: espressif/idf:${{ matrix.idf_ver }}
     env:
-      TEST_DIR: components/mosquitto/examples
+      TEST_DIR: components/mosquitto/examples/${{ matrix.example }}
       TARGET_TEST: broker
       TARGET_TEST_DIR: build_esp32_default
     steps:
@@ -31,14 +39,17 @@ jobs:
           . ${IDF_PATH}/export.sh
           pip install idf-component-manager idf-build-apps --upgrade
           python ci/build_apps.py -c ${TEST_DIR} -m components/mosquitto/.build-test-rules.yml
-          # upload only the target test artifacts
-          cd ${TEST_DIR}/${TARGET_TEST}
-          ${GITHUB_WORKSPACE}/ci/clean_build_artifacts.sh `pwd`/${TARGET_TEST_DIR}
-          zip -qur artifacts.zip ${TARGET_TEST_DIR}
+          if [ "${{ matrix.example }}" == "${TARGET_TEST}" ]; then
+            # upload only the target test artifacts
+            cd ${TEST_DIR}
+            ${GITHUB_WORKSPACE}/ci/clean_build_artifacts.sh `pwd`/${TARGET_TEST_DIR}
+            zip -qur artifacts.zip ${TARGET_TEST_DIR}
+          fi
       - uses: actions/upload-artifact@v4
+        if: ${{ matrix.example == 'broker' }}
         with:
           name: mosq_target_esp32_${{ matrix.idf_ver }}
-          path: ${{ env.TEST_DIR }}/${{ env.TARGET_TEST }}/artifacts.zip
+          path: ${{ env.TEST_DIR }}/artifacts.zip
           if-no-files-found: error
 
   test_mosq:

.github/workflows/pre_commit_check.yml

@@ -39,7 +39,7 @@ jobs:
           if ! pre-commit run --from-ref origin/HEAD --to-ref HEAD --hook-stage manual --show-diff-on-failure ; then
             echo ""
             echo "::notice::It looks like the commits in this PR have been made without having pre-commit hooks installed."
-            echo "::notice::Please see https://github.com/espressif/esp-protocols/CONTRIBUTING.md for instructions."
+            echo "::notice::Please see https://github.com/espressif/esp-protocols/blob/master/CONTRIBUTING.md for instructions."
             echo ""
             exit 1
           fi

.github/workflows/websocket__build-target-test.yml

@@ -65,14 +65,27 @@ jobs:
         with:
           name: websocket_bin_esp32_${{ matrix.idf_ver }}_${{ matrix.test.app }}
           path: ${{ env.TEST_DIR }}/ci/
-      - name: Install Python packages
+      - name: Run Example Test on target
+        working-directory: ${{ env.TEST_DIR }}
         env:
           PIP_EXTRA_INDEX_URL: "https://www.piwheels.org/simple"
         run: |
-          pip install --only-binary cryptography --extra-index-url https://dl.espressif.com/pypi/ -r $GITHUB_WORKSPACE/ci/requirements.txt
-      - name: Run Example Test on target
-        working-directory: ${{ env.TEST_DIR }}
-        run: |
+          export PYENV_ROOT="$HOME/.pyenv"
+          export PATH="$PYENV_ROOT/bin:$PATH"
+          eval "$(pyenv init --path)"
+          eval "$(pyenv init -)"
+          if ! pyenv versions --bare | grep -q '^3\.12\.6$'; then
+            echo "Installing Python 3.12.6..."
+            pyenv install -s 3.12.6
+          fi
+          if ! pyenv virtualenvs --bare | grep -q '^myenv$'; then
+            echo "Creating pyenv virtualenv 'myenv'..."
+            pyenv virtualenv 3.12.6 myenv
+          fi
+          pyenv activate myenv
+          python --version
+          pip install --prefer-binary cryptography pytest-embedded pytest-embedded-serial-esp pytest-embedded-idf pytest-custom_exit_code esptool
+          pip install --extra-index-url https://dl.espressif.com/pypi/ -r $GITHUB_WORKSPACE/ci/requirements.txt
           unzip ci/artifacts.zip -d ci
           for dir in `ls -d ci/build_*`; do
           rm -rf build sdkconfig.defaults

.gitignore

@@ -94,3 +94,9 @@ docs/html
 
 # esp-idf managed components
 **/managed_components/**
+
+# modem simulator uses esp-at clone
+common_components/modem_sim/modem_sim_esp32/
+
+# repository release tools
+release_notes.txt

.pre-commit-config.yaml

@@ -25,12 +25,8 @@ repos:
            (?x)^(
                .*.py
            )$
-  - repo: https://github.com/myint/unify
-    rev: v0.5
-    hooks:
-      - id: unify
-  - repo: https://github.com/pre-commit/mirrors-yapf
-    rev: "v0.32.0"
+  - repo: https://github.com/google/yapf
+    rev: "v0.43.0"
     hooks:
       - id: yapf
         args: ['style={based_on_style: google, column_limit: 160, indent_width: 4}']
@@ -39,7 +35,7 @@ repos:
     hooks:
       - id: isort
   - repo: https://github.com/myint/eradicate/
-    rev: v2.1.0
+    rev: 3.0.0
     hooks:
       - id: eradicate
   - repo: https://github.com/espressif/check-copyright/
@@ -61,8 +57,8 @@ repos:
   - repo: local
     hooks:
       - id: commit message scopes
-        name: "commit message must be scoped with: mdns, dns, modem, websocket, asio, mqtt_cxx, console, common, eppp, tls_cxx, mosq, sockutls, lws"
-        entry: '\A(?!(feat|fix|ci|bump|test|docs|chore)\((mdns|dns|modem|common|console|websocket|asio|mqtt_cxx|examples|eppp|tls_cxx|mosq|sockutls|lws)\)\:)'
+        name: "commit message must be scoped with: mdns, dns, modem, websocket, asio, mqtt_cxx, console, common, eppp, tls_cxx, mosq, sockutls, lws, modem_sim"
+        entry: '\A(?!(feat|fix|ci|bump|test|docs|chore)\((mdns|dns|modem|common|console|websocket|asio|mqtt_cxx|examples|eppp|tls_cxx|mosq|sockutls|lws|modem_sim)\)\:)'
         language: pygrep
         args: [--multiline]
         stages: [commit-msg]

ci/build_apps.py

@@ -56,7 +56,7 @@ if __name__ == '__main__':
         build_dir='build_@t_@w',
         config_rules_str=args.rules,
         build_log_filename='build_log.txt',
-        size_json_filename='size.json' if not args.linux else None,
+        size_json_filename=None,
         check_warnings=True,
         manifest_files=args.manifests,
         default_build_targets=SUPPORTED_TARGETS,
@@ -65,6 +65,7 @@ if __name__ == '__main__':
 
     sys.exit(
         build_apps(apps,
+                   verbose=2,
                    dry_run=False,
                    keep_going=False,
                    no_preserve=args.delete,

ci/config_env.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+# This script is used to set some common variables for the CI pipeline.
+
+set -e
+
+# MQTT public broker URI
+export CI_MQTT_BROKER_URI="test.mosquitto.org"

ci/ignore_build_warnings.txt

@@ -1 +1,7 @@
 DeprecationWarning: pkg_resources is deprecated as an API
+Warning: Deprecated: Option '--flash_size' is deprecated. Use '--flash-size' instead.
+Warning: Deprecated: Option '--flash_mode' is deprecated. Use '--flash-mode' instead.
+Warning: Deprecated: Option '--flash_freq' is deprecated. Use '--flash-freq' instead.
+Warning: Deprecated: Command 'sign_data' is deprecated. Use 'sign-data' instead.
+Warning: Deprecated: Command 'extract_public_key' is deprecated. Use 'extract-public-key' instead.
+warning: unknown kconfig symbol 'EXAMPLE_ETH_PHY_IP101'

ci/requirements.txt

@@ -6,3 +6,4 @@ dpkt
 pytest
 idf_build_apps
 netifaces
+esptool>=5.1.0

common_components/modem_sim/README.md

@@ -0,0 +1,51 @@
+# Modem Simulator Component
+
+A Wi-Fi modem simulator that extends ESP-AT with PPP server capabilities, turning ESP32 into a fully functional Wi-Fi modem. Perfect for testing AT commands and PPP connections without real hardware dependencies.
+
+## What it does
+
+- Extends ESP-AT firmware with PPP server functionality
+- Provides DATA mode for raw IP communication
+- Enables existing communication stacks (MQTT, HTTP, custom protocols) to work over Wi-Fi
+- Ideal for testing ESP-Modem library and CI reliability
+
+## Quick Start
+
+```bash
+cd common_components/modem_sim
+./install.sh
+source export.sh
+idf.py build
+```
+
+## Custom Platform/Module
+
+```bash
+./install.sh PLATFORM_ESP32S3 WROOM-32
+```
+
+## Configuration
+
+The `sdkconfig.defaults` includes:
+- Wi-Fi and Bluetooth enabled
+- PPP server support
+- AT commands for HTTP/MQTT
+- 4MB flash configuration
+
+## Project Structure
+
+```
+modem_sim/
+├── install.sh              # Installation script
+├── export.sh               # Environment setup
+├── sdkconfig.defaults      # Default configuration
+├── pppd_cmd/               # Custom PPP commands
+└── modem_sim_esp32/        # Generated ESP-AT build
+```
+
+## Use Cases
+
+- Testing ESP-Modem library without real hardware
+- Quick Wi-Fi connectivity for existing communication stacks
+- CI/CD testing with reliable modem simulation
+- Development and debugging of AT command implementations

common_components/modem_sim/export.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+source $IDF_PATH/export.sh
+
+export AT_CUSTOM_COMPONENTS="`pwd`/pppd_cmd"
+
+cd modem_sim_esp32/esp-at
+
+python -m pip install -r requirements.txt
+
+python build.py reconfigure

common_components/modem_sim/install.sh

@@ -0,0 +1,64 @@
+#!/bin/bash
+set -e
+
+# Create directory "modem_sim_esp32", go inside it
+# Usage: ./install.sh [platform] [module]
+
+SCRIPT_DIR=$(pwd)
+mkdir -p modem_sim_esp32
+cd modem_sim_esp32
+
+if [ -z "$IDF_PATH" ]; then
+    echo "Error: IDF_PATH environment variable is not set"
+    exit 1
+fi
+
+# Default ESP_AT_VERSION uses this specific commit from master to support new chips and features
+ESP_AT_VERSION="aa9d7e0e9b741744f7bf5bec3bbf887cff033d5f"
+
+# Shallow clone of esp-at.git at $ESP_AT_VERSION
+if [ ! -d "esp-at" ]; then
+    # cannot shallow clone from a specific commit, so we init, shallow fetch, and checkout
+    mkdir -p esp-at && cd esp-at && git init && git remote add origin https://github.com/espressif/esp-at.git
+    git fetch --depth 1 origin $ESP_AT_VERSION && git checkout $ESP_AT_VERSION
+else
+    echo "esp-at directory already exists, skipping clone."
+    cd esp-at
+fi
+
+# Add esp-idf directory which is a symlink to the $IDF_PATH
+if [ ! -L "esp-idf" ]; then
+    ln -sf "$IDF_PATH" esp-idf
+else
+    echo "esp-idf symlink already exists, skipping."
+fi
+
+# Create "build" directory
+mkdir -p build
+
+# Default values for platform and module
+platform="PLATFORM_ESP32"
+module="WROOM-32"
+
+# Override defaults if parameters are provided
+if [ ! -z "$1" ]; then
+    platform="$1"
+fi
+if [ ! -z "$2" ]; then
+    module="$2"
+fi
+
+# Create file "build/module_info.json" with content
+cat > build/module_info.json << EOF
+{
+    "platform": "$platform",
+    "module": "$module",
+    "description": "4MB, Wi-Fi + BLE, OTA, TX:17 RX:16",
+    "silence": 0
+}
+EOF
+
+cp "$SCRIPT_DIR/sdkconfig.defaults" "module_config/module_esp32_default/sdkconfig.defaults"
+
+echo "Installation completed successfully!"
+echo "Created modem_sim_esp32 directory with esp-at repository and configuration"

common_components/modem_sim/pppd_cmd/CMakeLists.txt

@@ -0,0 +1,6 @@
+idf_component_register(
+    SRCS additional_commands.c
+    INCLUDE_DIRS include
+    REQUIRES at freertos nvs_flash)
+
+idf_component_set_property(${COMPONENT_NAME} WHOLE_ARCHIVE TRUE)

common_components/modem_sim/pppd_cmd/additional_commands.c

@@ -0,0 +1,411 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include "esp_at.h"
+#include "driver/gpio.h"
+#include "driver/uart.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/event_groups.h"
+#include "freertos/semphr.h"
+#include "freertos/queue.h"
+#include "esp_netif.h"
+#include "esp_netif_ppp.h"
+#include "esp_check.h"
+#include "esp_http_server.h"
+#include "esp_timer.h"
+
+static uint8_t at_test_cmd_test(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "test command: <AT%s=?> is executed\r\n", cmd_name);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_query_cmd_test(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "query command: <AT%s?> is executed\r\n", cmd_name);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_setup_cmd_test(uint8_t para_num)
+{
+    uint8_t index = 0;
+    printf("setup command: <AT%s=%d> is executed\r\n", esp_at_get_current_cmd_name(), para_num);
+
+    // get first parameter, and parse it into a digit
+    int32_t digit = 0;
+    if (esp_at_get_para_as_digit(index++, &digit) != ESP_AT_PARA_PARSE_RESULT_OK) {
+        return ESP_AT_RESULT_CODE_ERROR;
+    }
+    printf("digit: %d\r\n", digit);
+
+    // get second parameter, and parse it into a string
+    uint8_t *str = NULL;
+    if (esp_at_get_para_as_str(index++, &str) != ESP_AT_PARA_PARSE_RESULT_OK) {
+        return ESP_AT_RESULT_CODE_ERROR;
+    }
+    printf("string: %s\r\n", str);
+
+    // allocate a buffer and construct the data, then send the data to mcu via interface (uart/spi/sdio/socket)
+    uint8_t *buffer = (uint8_t *)malloc(512);
+    if (!buffer) {
+        return ESP_AT_RESULT_CODE_ERROR;
+    }
+    int len = snprintf((char *)buffer, 512, "setup command: <AT%s=%d,\"%s\"> is executed\r\n",
+                       esp_at_get_current_cmd_name(), digit, str);
+    esp_at_port_write_data(buffer, len);
+
+    // remember to free the buffer
+    free(buffer);
+
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+#define TAG "at_custom_cmd"
+static esp_netif_t *s_netif = NULL;
+static httpd_handle_t http_server = NULL;
+
+static void on_ppp_event(void *arg, esp_event_base_t base, int32_t event_id, void *data)
+{
+    esp_netif_t **netif = data;
+    if (base == NETIF_PPP_STATUS && event_id == NETIF_PPP_ERRORUSER) {
+        printf("Disconnected!");
+    }
+}
+
+static void on_ip_event(void *arg, esp_event_base_t base, int32_t event_id, void *data)
+{
+    ip_event_got_ip_t *event = (ip_event_got_ip_t *)data;
+    esp_netif_t *netif = event->esp_netif;
+    if (event_id == IP_EVENT_PPP_GOT_IP) {
+        printf("Got IPv4 event: Interface \"%s(%s)\" address: " IPSTR, esp_netif_get_desc(netif),
+               esp_netif_get_ifkey(netif), IP2STR(&event->ip_info.ip));
+        ESP_ERROR_CHECK(esp_netif_napt_enable(s_netif));
+
+    } else if (event_id == IP_EVENT_PPP_LOST_IP) {
+        ESP_LOGI(TAG, "Disconnected");
+    }
+}
+
+static SemaphoreHandle_t at_sync_sema = NULL;
+static void wait_data_callback(void)
+{
+    static uint8_t buffer[1500] = {0};
+    int len = esp_at_port_read_data(buffer, sizeof(buffer) - 1);
+
+    // Check for the escape sequence "+++" in the received data
+    const uint8_t escape_seq[] = "+++";
+    uint8_t *escape_ptr = memmem(buffer, len, escape_seq, 3);
+
+    if (escape_ptr != NULL) {
+        printf("Found +++ sequence, signal to the command processing thread\n");
+
+        int data_before_escape = escape_ptr - buffer;
+        if (data_before_escape > 0) {
+            esp_netif_receive(s_netif, buffer, data_before_escape, NULL);
+        }
+
+        if (at_sync_sema) {
+            xSemaphoreGive(at_sync_sema);
+        }
+        return;
+    }
+    esp_netif_receive(s_netif, buffer, len, NULL);
+}
+
+static esp_err_t transmit(void *h, void *buffer, size_t len)
+{
+    printf("transmit: %d bytes\n", len);
+    esp_at_port_write_data(buffer, len);
+    return ESP_OK;
+}
+
+static uint8_t at_exe_cmd_test(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "execute command: <AT%s> is executed\r\n", cmd_name);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+    printf("Command <AT%s> executed successfully\r\n", cmd_name);
+    if (!at_sync_sema) {
+        at_sync_sema = xSemaphoreCreateBinary();
+        assert(at_sync_sema != NULL);
+        esp_netif_driver_ifconfig_t driver_cfg = {
+            .handle = (void *)1,
+            .transmit = transmit,
+        };
+        const esp_netif_driver_ifconfig_t *ppp_driver_cfg = &driver_cfg;
+
+        esp_netif_inherent_config_t base_netif_cfg = ESP_NETIF_INHERENT_DEFAULT_PPP();
+        esp_netif_config_t netif_ppp_config = { .base = &base_netif_cfg,
+                                                .driver = ppp_driver_cfg,
+                                                .stack = ESP_NETIF_NETSTACK_DEFAULT_PPP
+                                              };
+
+        s_netif = esp_netif_new(&netif_ppp_config);
+        esp_netif_ppp_config_t netif_params;
+        ESP_ERROR_CHECK(esp_netif_ppp_get_params(s_netif, &netif_params));
+        netif_params.ppp_our_ip4_addr.addr = ESP_IP4TOADDR(192, 168, 11, 1);
+        netif_params.ppp_their_ip4_addr.addr = ESP_IP4TOADDR(192, 168, 11, 2);
+        netif_params.ppp_error_event_enabled = true;
+        ESP_ERROR_CHECK(esp_netif_ppp_set_params(s_netif, &netif_params));
+        if (esp_event_handler_register(IP_EVENT, ESP_EVENT_ANY_ID, on_ip_event, NULL) != ESP_OK) {
+            printf("Failed to register IP event handler");
+        }
+        if (esp_event_handler_register(NETIF_PPP_STATUS, ESP_EVENT_ANY_ID, on_ppp_event, NULL) !=  ESP_OK) {
+            printf("Failed to register NETIF_PPP_STATUS event handler");
+        }
+
+
+    }
+    esp_at_port_write_data((uint8_t *)"CONNECT\r\n", strlen("CONNECT\r\n"));
+
+    // set the callback function which will be called by AT port after receiving the input data
+    esp_at_port_enter_specific(wait_data_callback);
+    esp_netif_action_start(s_netif, 0, 0, 0);
+    esp_netif_action_connected(s_netif, 0, 0, 0);
+
+    while (xSemaphoreTake(at_sync_sema, pdMS_TO_TICKS(1000)) == pdFALSE) {
+        printf(".");
+    }
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_test_cereg(uint8_t *cmd_name)
+{
+    printf("%s: AT command <AT%s> is executed\r\n", __func__, cmd_name);
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_query_cereg(uint8_t *cmd_name)
+{
+    printf("%s: AT command <AT%s> is executed\r\n", __func__, cmd_name);
+    static uint8_t buffer[] = "+CEREG: 7,8\r\n";
+    esp_at_port_write_data(buffer, sizeof(buffer));
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_setup_cereg(uint8_t num)
+{
+    printf("%s: AT command <AT%d> is executed\r\n", __func__, num);
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_exe_cereg(uint8_t *cmd_name)
+{
+    printf("%s: AT command <AT%s> is executed\r\n", __func__, cmd_name);
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static esp_err_t hello_get_handler(httpd_req_t *req)
+{
+    const char* resp_str = "Hello from ESP-AT HTTP Server!";
+    httpd_resp_send(req, resp_str, HTTPD_RESP_USE_STRLEN);
+    return ESP_OK;
+}
+
+static esp_err_t root_get_handler(httpd_req_t *req)
+{
+    const char* resp_str = "ESP-AT HTTP Server is running";
+    httpd_resp_send(req, resp_str, HTTPD_RESP_USE_STRLEN);
+    return ESP_OK;
+}
+
+static esp_err_t test_get_handler(httpd_req_t *req)
+{
+    const char* resp_str = "{\"status\":\"success\",\"message\":\"Test endpoint working\",\"timestamp\":12345}";
+    httpd_resp_set_type(req, "application/json");
+    httpd_resp_send(req, resp_str, HTTPD_RESP_USE_STRLEN);
+    return ESP_OK;
+}
+
+static esp_err_t async_get_handler(httpd_req_t *req)
+{
+    printf("Starting async chunked response handler\r\n");
+
+    // Set content type for plain text response
+    httpd_resp_set_type(req, "text/plain");
+
+    // Static counter to track requests
+    static uint8_t req_count = 0;
+    req_count++;
+
+    // Send initial response with request count
+    char buffer[256];
+    snprintf(buffer, sizeof(buffer), "=== Async Response #%d ===\r\n", req_count);
+    httpd_resp_sendstr_chunk(req, buffer);
+
+    // Long message broken into chunks
+    const char* chunks[] = {
+        "This is a simulated slow server response.\r\n",
+        "Chunk 1: The ESP-AT HTTP server is demonstrating...\r\n",
+        "Chunk 2: ...asynchronous chunked transfer encoding...\r\n",
+        "Chunk 3: ...with artificial delays between chunks...\r\n",
+        "Chunk 4: ...to simulate real-world network conditions.\r\n",
+        "Chunk 5: Processing data... please wait...\r\n",
+        "Chunk 6: Still processing... almost done...\r\n",
+        "Chunk 7: Final chunk - transfer complete!\r\n",
+        "=== END OF RESPONSE ===\r\n"
+    };
+
+    int num_chunks = sizeof(chunks) / sizeof(chunks[0]);
+
+    // Send each chunk with delays
+    for (int i = 0; i < num_chunks; i++) {
+        // Add a delay to simulate slow processing
+        vTaskDelay(pdMS_TO_TICKS(1500)); // 1.5 second delay between chunks
+
+        // Add chunk number and timestamp
+        snprintf(buffer, sizeof(buffer), "[%d/%d] [%d ms] %s",
+                 i + 1, num_chunks, (int)(esp_timer_get_time() / 1000), chunks[i]);
+
+        printf("Sending chunk %d: %s", i + 1, chunks[i]);
+        httpd_resp_sendstr_chunk(req, buffer);
+    }
+
+    // Add final summary
+    vTaskDelay(pdMS_TO_TICKS(500));
+    snprintf(buffer, sizeof(buffer), "\r\nTransfer completed in %d chunks with delays.\r\n", num_chunks);
+    httpd_resp_sendstr_chunk(req, buffer);
+
+    // Send NULL to signal end of chunked transfer
+    httpd_resp_sendstr_chunk(req, NULL);
+
+    printf("Async chunked response completed\r\n");
+    return ESP_OK;
+}
+
+static const httpd_uri_t hello = {
+    .uri       = "/hello",
+    .method    = HTTP_GET,
+    .handler   = hello_get_handler,
+    .user_ctx  = NULL
+};
+
+static const httpd_uri_t root = {
+    .uri       = "/",
+    .method    = HTTP_GET,
+    .handler   = root_get_handler,
+    .user_ctx  = NULL
+};
+
+static const httpd_uri_t test = {
+    .uri       = "/test",
+    .method    = HTTP_GET,
+    .handler   = test_get_handler,
+    .user_ctx  = NULL
+};
+
+static const httpd_uri_t async_uri = {
+    .uri       = "/async",
+    .method    = HTTP_GET,
+    .handler   = async_get_handler,
+    .user_ctx  = NULL
+};
+
+static esp_err_t start_http_server(void)
+{
+    if (http_server != NULL) {
+        printf("HTTP server already running\r\n");
+        return ESP_OK;
+    }
+
+    httpd_config_t config = HTTPD_DEFAULT_CONFIG();
+    config.server_port = 8080;
+    config.lru_purge_enable = true;
+
+    printf("Starting HTTP server on port: %d\r\n", config.server_port);
+    if (httpd_start(&http_server, &config) == ESP_OK) {
+        printf("Registering URI handlers\r\n");
+        httpd_register_uri_handler(http_server, &hello);
+        httpd_register_uri_handler(http_server, &root);
+        httpd_register_uri_handler(http_server, &test);
+        httpd_register_uri_handler(http_server, &async_uri);
+        return ESP_OK;
+    }
+
+    printf("Error starting HTTP server!\r\n");
+    return ESP_FAIL;
+}
+
+static esp_err_t stop_http_server(void)
+{
+    if (http_server != NULL) {
+        httpd_stop(http_server);
+        http_server = NULL;
+        printf("HTTP server stopped\r\n");
+        return ESP_OK;
+    }
+    return ESP_OK;
+}
+
+/* HTTP Server AT Commands */
+static uint8_t at_test_httpd(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "AT%s=<0/1> - Start/Stop HTTP server\r\n", cmd_name);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_query_httpd(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "+HTTPD:%d\r\n", http_server != NULL ? 1 : 0);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_setup_httpd(uint8_t para_num)
+{
+    int32_t action = 0;
+    if (esp_at_get_para_as_digit(0, &action) != ESP_AT_PARA_PARSE_RESULT_OK) {
+        return ESP_AT_RESULT_CODE_ERROR;
+    }
+
+    if (action == 1) {
+        if (start_http_server() == ESP_OK) {
+            printf("HTTP server started successfully\r\n");
+            return ESP_AT_RESULT_CODE_OK;
+        }
+    } else if (action == 0) {
+        if (stop_http_server() == ESP_OK) {
+            return ESP_AT_RESULT_CODE_OK;
+        }
+    }
+
+    return ESP_AT_RESULT_CODE_ERROR;
+}
+
+static uint8_t at_exe_httpd(uint8_t *cmd_name)
+{
+    // Default action: start server
+    if (start_http_server() == ESP_OK) {
+        printf("HTTP server started via execute command\r\n");
+        return ESP_AT_RESULT_CODE_OK;
+    }
+    return ESP_AT_RESULT_CODE_ERROR;
+}
+
+
+static const esp_at_cmd_struct at_custom_cmd[] = {
+    {"+PPPD", at_test_cmd_test, at_query_cmd_test, at_setup_cmd_test, at_exe_cmd_test},
+    {"+CEREG", at_test_cereg, at_query_cereg, at_setup_cereg, at_exe_cereg},
+    {"+HTTPD", at_test_httpd, at_query_httpd, at_setup_httpd, at_exe_httpd},
+};
+
+bool esp_at_custom_cmd_register(void)
+{
+    return esp_at_custom_cmd_array_regist(at_custom_cmd, sizeof(at_custom_cmd) / sizeof(esp_at_cmd_struct));
+}
+
+ESP_AT_CMD_SET_INIT_FN(esp_at_custom_cmd_register, 1);

common_components/modem_sim/pppd_cmd/include/at_custom_cmd.h

@@ -0,0 +1,12 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#pragma once
+#include "esp_at_core.h"
+#include "esp_at.h"
+
+/**
+ * @brief You can include more header files here for your own AT commands.
+ */

common_components/modem_sim/sdkconfig.defaults

@@ -0,0 +1,79 @@
+# This file was generated using idf.py save-defconfig. It can be edited manually.
+# Espressif IoT Development Framework (ESP-IDF) 5.4.1 Project Minimal Configuration
+#
+CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE=y
+CONFIG_APP_PROJECT_VER_FROM_CONFIG=y
+CONFIG_APP_PROJECT_VER="v4.1.0.0-dev"
+CONFIG_ESPTOOLPY_FLASHSIZE_4MB=y
+CONFIG_PARTITION_TABLE_CUSTOM=y
+CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="module_config/module_esp32_default/partitions_at.csv"
+CONFIG_PARTITION_TABLE_MD5=n
+CONFIG_AT_CUSTOMIZED_PARTITION_TABLE_FILE="module_config/module_esp32_default/at_customize.csv"
+CONFIG_BT_ENABLED=y
+CONFIG_BT_BTU_TASK_STACK_SIZE=5120
+CONFIG_BT_BLE_BLUFI_ENABLE=y
+CONFIG_BT_STACK_NO_LOG=y
+CONFIG_BT_BLE_DYNAMIC_ENV_MEMORY=y
+CONFIG_BTDM_CTRL_MODE_BTDM=y
+CONFIG_BTDM_CTRL_LPCLK_SEL_EXT_32K_XTAL=y
+CONFIG_BTDM_SCAN_DUPL_CACHE_SIZE=200
+CONFIG_ESP_TLS_PSK_VERIFICATION=y
+CONFIG_ESP_TLS_INSECURE=y
+CONFIG_ESP_TLS_SKIP_SERVER_CERT_VERIFY=y
+CONFIG_ESP_ERR_TO_NAME_LOOKUP=n
+CONFIG_GPIO_ESP32_SUPPORT_SWITCH_SLP_PULL=y
+CONFIG_ETH_DMA_RX_BUFFER_NUM=3
+CONFIG_ETH_DMA_TX_BUFFER_NUM=3
+CONFIG_HTTPD_MAX_REQ_HDR_LEN=1024
+CONFIG_HTTPD_MAX_URI_LEN=1024
+CONFIG_ESP_HTTPS_OTA_ALLOW_HTTP=y
+CONFIG_RTC_CLK_SRC_EXT_CRYS=y
+CONFIG_RTC_EXT_CRYST_ADDIT_CURRENT=y
+CONFIG_RTC_CLK_CAL_CYCLES=1024
+CONFIG_PM_ENABLE=y
+CONFIG_PM_SLP_DISABLE_GPIO=y
+CONFIG_ESP_DEFAULT_CPU_FREQ_MHZ_80=y
+CONFIG_ESP_TASK_WDT_PANIC=y
+CONFIG_ESP_TASK_WDT_TIMEOUT_S=60
+CONFIG_ESP_DEBUG_OCDAWARE=n
+CONFIG_ESP_WIFI_IRAM_OPT=n
+CONFIG_ESP_WIFI_RX_IRAM_OPT=n
+CONFIG_ESP_WIFI_SLP_IRAM_OPT=y
+CONFIG_ESP_WIFI_SLP_BEACON_LOST_OPT=y
+CONFIG_ESP_WIFI_ESPNOW_MAX_ENCRYPT_NUM=0
+CONFIG_FATFS_LFN_HEAP=y
+CONFIG_FREERTOS_UNICORE=y
+CONFIG_FREERTOS_HZ=1000
+CONFIG_FREERTOS_USE_TICKLESS_IDLE=y
+CONFIG_FREERTOS_CHECK_MUTEX_GIVEN_BY_OWNER=n
+CONFIG_FREERTOS_PLACE_FUNCTIONS_INTO_FLASH=y
+CONFIG_HEAP_PLACE_FUNCTION_INTO_FLASH=y
+CONFIG_LOG_DEFAULT_LEVEL_ERROR=y
+CONFIG_LWIP_MAX_SOCKETS=16
+CONFIG_LWIP_SO_LINGER=y
+CONFIG_LWIP_SO_RCVBUF=y
+CONFIG_LWIP_IP4_REASSEMBLY=y
+CONFIG_LWIP_IP6_REASSEMBLY=y
+CONFIG_LWIP_IPV6_AUTOCONFIG=y
+CONFIG_LWIP_TCP_MAXRTX=6
+CONFIG_LWIP_TCP_SYNMAXRTX=3
+CONFIG_LWIP_PPP_SUPPORT=y
+CONFIG_LWIP_PPP_SERVER_SUPPORT=y
+CONFIG_LWIP_SNTP_MAX_SERVERS=3
+CONFIG_LWIP_SNTP_STARTUP_DELAY=n
+CONFIG_MBEDTLS_DYNAMIC_BUFFER=y
+CONFIG_MBEDTLS_DYNAMIC_FREE_CONFIG_DATA=y
+CONFIG_MBEDTLS_SSL_KEEP_PEER_CERTIFICATE=n
+CONFIG_MBEDTLS_HAVE_TIME_DATE=y
+CONFIG_MBEDTLS_DHM_C=y
+CONFIG_NEWLIB_NANO_FORMAT=y
+CONFIG_VFS_SUPPORT_TERMIOS=n
+CONFIG_WL_SECTOR_SIZE_512=y
+CONFIG_AT_PROCESS_TASK_STACK_SIZE=6144
+CONFIG_AT_MQTT_COMMAND_SUPPORT=y
+CONFIG_AT_HTTP_COMMAND_SUPPORT=y
+CONFIG_AT_BLE_COMMAND_SUPPORT=n
+CONFIG_AT_BLE_HID_COMMAND_SUPPORT=n
+CONFIG_AT_BLUFI_COMMAND_SUPPORT=n
+CONFIG_LWIP_IP_FORWARD=y
+CONFIG_LWIP_IPV4_NAPT=y

components/asio/port/src/asio_stub.cpp

@@ -28,7 +28,7 @@ posix_event::posix_event()
 }
 } // namespace asio::detail
 
-extern "C" int pause (void)
+extern "C" int pause(void)
 {
     while (true) {
         ::sleep(UINT_MAX);

components/console_cmd_ping/.cz.yaml

@@ -3,6 +3,6 @@ commitizen:
   bump_message: 'bump(console): $current_version -> $new_version'
   pre_bump_hooks: python ../../ci/changelog.py console_cmd_ping
   tag_format: console_cmd_ping-v$version
-  version: 1.1.0
+  version: 1.2.0
   version_files:
   - idf_component.yml

components/console_cmd_ping/CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## [1.2.0](https://github.com/espressif/esp-protocols/commits/console_cmd_ping-v1.2.0)
+
+### Features
+
+- Add support for interface argument ([90ddb04e](https://github.com/espressif/esp-protocols/commit/90ddb04e))
+
 ## [1.1.0](https://github.com/espressif/esp-protocols/commits/console_cmd_ping-v1.1.0)
 
 ### Features

components/console_cmd_ping/README.md

@@ -48,7 +48,7 @@ For more details refer [IDF Component Manager](https://docs.espressif.com/projec
 
 ### ping:
 ```
-ping  [-W <t>] [-i <t>] [-s <n>] [-c <n>] [-Q <n>] [-T <n>] <host>
+ping  [-W <t>] [-i <t>] [-s <n>] [-c <n>] [-Q <n>] [-T <n>] [-I <n>] <host>
   send ICMP ECHO_REQUEST to network hosts
   -W, --timeout=<t>  Time to wait for a response, in seconds
   -i, --interval=<t>  Wait interval seconds between sending each packet
@@ -56,6 +56,7 @@ ping  [-W <t>] [-i <t>] [-s <n>] [-c <n>] [-Q <n>] [-T <n>] <host>
   -c, --count=<n>  Stop after sending count packets
   -Q, --tos=<n>  Set Type of Service related bits in IP datagrams
   -T, --ttl=<n>  Set Time to Live related bits in IP datagrams
+  -I, --interface=<n>  Set Interface number 0=no-interface selected, >0 netif number + 1 (1 is usually 'lo0')
         <host>  Host address
 
 getaddrinfo  [-f <AF>] [-F <FLAGS>]... [-p <port>] <hostname>
@@ -121,8 +122,8 @@ getaddrinfo -f AF_INET -F AI_PASSIVE www.example.com
 ping www.example.com
 ```
 
-2. To specify additional options, such as timeout, interval, packet size, etc.:
+2. To specify additional options, such as timeout, interval, packet size, interface, etc.:
 
 ```
-ping -W 5 -i 1 -s 64 -c 4 -Q 0x10 -T 64 www.example.com
+ping -W 5 -i 1 -s 64 -c 4 -Q 0x10 -T 64 -I 0 www.example.com
 ```

components/console_cmd_ping/console_ping.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -99,6 +99,7 @@ static struct {
     struct arg_int *count;
     struct arg_int *tos;
     struct arg_int *ttl;
+    struct arg_int *interface;
     struct arg_str *host;
     struct arg_end *end;
 } ping_args;
@@ -137,6 +138,10 @@ static int do_ping_cmd(int argc, char **argv)
         config.ttl = (uint32_t)(ping_args.ttl->ival[0]);
     }
 
+    if (ping_args.interface->count > 0) {
+        config.interface = (uint32_t)(ping_args.interface->ival[0]);
+    }
+
     // parse IP address
     struct sockaddr_in6 sock_addr6;
     ip_addr_t target_addr = {0};
@@ -155,12 +160,12 @@ static int do_ping_cmd(int argc, char **argv)
         }
         if (res->ai_family == AF_INET) {
 #if CONFIG_LWIP_IPV4
-            struct in_addr addr4 = ((struct sockaddr_in *) (res->ai_addr))->sin_addr;
+            struct in_addr addr4 = ((struct sockaddr_in *)(res->ai_addr))->sin_addr;
             inet_addr_to_ip4addr(ip_2_ip4(&target_addr), &addr4);
 #endif
         } else {
 #if CONFIG_LWIP_IPV6
-            struct in6_addr addr6 = ((struct sockaddr_in6 *) (res->ai_addr))->sin6_addr;
+            struct in6_addr addr6 = ((struct sockaddr_in6 *)(res->ai_addr))->sin6_addr;
             inet6_addr_to_ip6addr(ip_2_ip6(&target_addr), &addr6);
 #endif
         }
@@ -204,6 +209,7 @@ esp_err_t console_cmd_ping_register(void)
     ping_args.count = arg_int0("c", "count", "<n>", "Stop after sending count packets");
     ping_args.tos = arg_int0("Q", "tos", "<n>", "Set Type of Service related bits in IP datagrams");
     ping_args.ttl = arg_int0("T", "ttl", "<n>", "Set Time to Live related bits in IP datagrams");
+    ping_args.interface = arg_int0("I", "interface", "<n>", "Set Interface number");
     ping_args.host = arg_str1(NULL, NULL, "<host>", "Host address");
     ping_args.end = arg_end(1);
     const esp_console_cmd_t ping_cmd = {

components/console_cmd_ping/idf_component.yml

@@ -1,4 +1,4 @@
-version: 1.1.0
+version: 1.2.0
 url: https://github.com/espressif/esp-protocols/tree/master/components/console_cmd_ping
 description: The component provides a console where the 'ping' command can be executed.
 dependencies:

components/eppp_link/.cz.yaml

@@ -3,6 +3,6 @@ commitizen:
   bump_message: 'bump(eppp): $current_version -> $new_version'
   pre_bump_hooks: python ../../ci/changelog.py eppp_link
   tag_format: eppp-v$version
-  version: 0.2.0
+  version: 1.1.3
   version_files:
   - idf_component.yml

components/eppp_link/CHANGELOG.md

@@ -1,5 +1,65 @@
 # Changelog
 
+## [1.1.3](https://github.com/espressif/esp-protocols/commits/eppp-v1.1.3)
+
+### Bug Fixes
+
+- Fix test dependency issue on driver ([1ace92c2](https://github.com/espressif/esp-protocols/commit/1ace92c2))
+- Fix tun netif to (optionally) return errors ([7a6cf0f9](https://github.com/espressif/esp-protocols/commit/7a6cf0f9))
+
+## [1.1.2](https://github.com/espressif/esp-protocols/commits/eppp-v1.1.2)
+
+### Bug Fixes
+
+- Update uart driver deps per IDF > v5.3 ([92e14607](https://github.com/espressif/esp-protocols/commit/92e14607))
+
+## [1.1.1](https://github.com/espressif/esp-protocols/commits/eppp-v1.1.1)
+
+### Bug Fixes
+
+- Fix getting context for channel API ([94563cdc](https://github.com/espressif/esp-protocols/commit/94563cdc))
+- Cover more combinations in build tests ([e0b8de8f](https://github.com/espressif/esp-protocols/commit/e0b8de8f))
+
+## [1.1.0](https://github.com/espressif/esp-protocols/commits/eppp-v1.1.0)
+
+### Features
+
+- Add support for UART flow control ([cd57f1bb](https://github.com/espressif/esp-protocols/commit/cd57f1bb), [#870](https://github.com/espressif/esp-protocols/issues/870))
+
+### Bug Fixes
+
+- Fix SPI transport to allow already init GPIO ISR ([497ee2d6](https://github.com/espressif/esp-protocols/commit/497ee2d6), [#868](https://github.com/espressif/esp-protocols/issues/868))
+- Fix stack-overflow in ping task for TUN netif ([b2568a3d](https://github.com/espressif/esp-protocols/commit/b2568a3d), [#867](https://github.com/espressif/esp-protocols/issues/867))
+
+### Updated
+
+- ci(common): Update test component dir for IDFv6.0 ([18418c83](https://github.com/espressif/esp-protocols/commit/18418c83))
+
+## [1.0.1](https://github.com/espressif/esp-protocols/commits/eppp-v1.0.1)
+
+### Bug Fixes
+
+- Support for IPv4-only mode ([653328ba](https://github.com/espressif/esp-protocols/commit/653328ba), [#864](https://github.com/espressif/esp-protocols/issues/864))
+
+## [1.0.0](https://github.com/espressif/esp-protocols/commits/eppp-v1.0.0)
+
+### Features
+
+- Add support for custom channels ([4ee9360f](https://github.com/espressif/esp-protocols/commit/4ee9360f))
+
+## [0.3.1](https://github.com/espressif/esp-protocols/commits/eppp-v0.3.1)
+
+### Bug Fixes
+
+- Fix NETIF_PPP_STATUS link issue if PPP disabled in lwip ([077ea0bb](https://github.com/espressif/esp-protocols/commit/077ea0bb))
+
+## [0.3.0](https://github.com/espressif/esp-protocols/commits/eppp-v0.3.0)
+
+### Features
+
+- Add support for TUN interface ([2ff150c3](https://github.com/espressif/esp-protocols/commit/2ff150c3))
+- Add support for transport via Ethernet link ([a21ce883](https://github.com/espressif/esp-protocols/commit/a21ce883))
+
 ## [0.2.0](https://github.com/espressif/esp-protocols/commits/eppp-v0.2.0)
 
 ### Features

components/eppp_link/CMakeLists.txt

@@ -1,3 +1,33 @@
-idf_component_register(SRCS eppp_link.c eppp_sdio_slave.c eppp_sdio_host.c
+if("${IDF_VERSION_MAJOR}.${IDF_VERSION_MINOR}" VERSION_GREATER "5.3")
+    set(driver_deps esp_driver_gpio esp_driver_spi esp_driver_uart esp_driver_sdio)
+else()
+    set(driver_deps driver)
+endif()
+
+if(CONFIG_EPPP_LINK_DEVICE_ETH)
+    set(transport_src eppp_eth.c)
+endif()
+
+if(CONFIG_EPPP_LINK_DEVICE_SPI)
+    set(transport_src eppp_spi.c)
+endif()
+
+if(CONFIG_EPPP_LINK_DEVICE_UART)
+    set(transport_src eppp_uart.c)
+endif()
+
+if(CONFIG_EPPP_LINK_DEVICE_SDIO)
+    set(transport_src eppp_sdio.c eppp_sdio_slave.c eppp_sdio_host.c)
+endif()
+
+if(NOT CONFIG_EPPP_LINK_USES_PPP)
+    set(netif_src eppp_netif_tun.c)
+endif()
+
+idf_component_register(SRCS eppp_link.c ${transport_src} ${netif_src}
                     INCLUDE_DIRS "include"
-                    PRIV_REQUIRES esp_netif esp_driver_spi esp_driver_gpio esp_timer driver)
+                    PRIV_REQUIRES esp_netif esp_timer esp_eth ${driver_deps})
+
+if(CONFIG_EPPP_LINK_DEVICE_ETH)
+    idf_component_optional_requires(PRIVATE ethernet_init espressif__ethernet_init)
+endif()

components/eppp_link/Kconfig

@@ -1,10 +1,16 @@
 menu "eppp_link"
 
-    config EPPP_LINK_USES_LWIP
-        bool
-        default "y"
+    config EPPP_LINK_USES_PPP
+        bool "Use PPP network interface"
+        default "n"
         select LWIP_PPP_SUPPORT
         select LWIP_PPP_SERVER_SUPPORT
+        help
+            Enable this option to use PPP network interface.
+            This is useful when pairing with another PPP device,
+            e.g. pppd service on Linux.
+            By default EPPP_LINK uses plain TUN interface,
+            relying on transports to split on packet boundaries.
 
     choice EPPP_LINK_DEVICE
         prompt "Choose PPP device"
@@ -28,6 +34,16 @@ menu "eppp_link"
             help
                 Use SDIO.
 
+        config EPPP_LINK_DEVICE_ETH
+            bool "Ethernet"
+            depends on SOC_EMAC_SUPPORTED
+            help
+                Use Ethernet.
+                This transport could employ a full fledged Ethernet connection
+                between two EPPP nodes via standard Ethernet cable.
+                It could be also effectively connected directly on PCB, EMAC to EMAC,
+                without any Ethernet PHY chips (using eth_dummy_phy driver).
+
     endchoice
 
     config EPPP_LINK_CONN_MAX_RETRY
@@ -67,4 +83,31 @@ menu "eppp_link"
 
     endchoice
 
+    config EPPP_LINK_ETHERNET_OUR_ADDRESS
+        string "MAC address our local node"
+        default "06:00:00:00:00:01"
+        depends on EPPP_LINK_DEVICE_ETH
+
+    config EPPP_LINK_ETHERNET_THEIR_ADDRESS
+        string "MAC address the remote node"
+        default "06:00:00:00:00:02"
+        depends on EPPP_LINK_DEVICE_ETH
+
+    config EPPP_LINK_CHANNELS_SUPPORT
+        bool "Enable channel support (multiple logical channels)"
+        default n
+        depends on !EPPP_LINK_DEVICE_ETH
+        help
+            Enable support for multiple logical channels in the EPPP link layer.
+            When enabled, you can configure the number of channels used for communication.
+
+    config EPPP_LINK_NR_OF_CHANNELS
+        int "Number of logical channels"
+        depends on EPPP_LINK_CHANNELS_SUPPORT && !EPPP_LINK_DEVICE_ETH
+        range 1 8
+        default 2
+        help
+            Set the number of logical channels for EPPP link communication.
+            Each channel can be used for independent data streams.
+
 endmenu

components/eppp_link/README.md

@@ -1,24 +1,74 @@
 # ESP PPP Link component (eppp_link)
 
-The component provides a general purpose connectivity engine between two microcontrollers, one acting as PPP server (slave), the other one as PPP client (host).
-This component could be used for extending network using physical serial connection. Applications could vary from providing PRC engine for multiprocessor solutions to serial connection to POSIX machine. This uses a standard PPP protocol to negotiate IP addresses and networking, so standard PPP toolset could be used, e.g. a `pppd` service on linux. Typical application is a WiFi connectivity provider for chips that do not have WiFi
+The component provides a general purpose connectivity engine between two microcontrollers, one acting as PPP server, the other one as PPP client.
+This component could be used for extending network using physical serial connection. Applications could vary from providing RPC engine for multiprocessor solutions to serial connection to POSIX machine. This uses a standard PPP protocol (if enabled) to negotiate IP addresses and networking, so standard PPP toolset could be used, e.g. a `pppd` service on linux. Typical application is a WiFi connectivity provider for chips that do not have WiFi.
+Uses simplified TUN network interface by default to enable faster data transfer on non-UART transports.
 
 ## Typical application
 
 Using this component we can construct a WiFi connectivity gateway on PPP channel. The below diagram depicts an application where
 PPP server is running on a WiFi capable chip with NAPT module translating packets between WiFi and PPPoS interface.
-We usually call this node a SLAVE microcontroller. The "HOST" microcontroller runs PPP client and connects only to the serial line,
-brings in the WiFi connectivity from the "SLAVE" microcontroller.
+We usually call this node a communication coprocessor, or a "SLAVE" microcontroller.
+The main microcontroller (sometimes also called the "HOST") runs PPP client and connects only to the serial line,
+brings in the WiFi connectivity from the communication coprocessor.
 
 ```
-             SLAVE micro                                  HOST micro
-    \|/  +----------------+                           +----------------+
-     |   |                |          serial line      |                |
-     +---+ WiFi NAT PPPoS |=== UART / SPI / SDIO =====| PPPoS client   |
-         |        (server)|                           |                |
-         +----------------+                           +----------------+
+        Communication coprocessor                        Main microcontroller
+    \|/  +----------------+                               +----------------+
+     |   |                |       (serial) line           |                |
+     +---+ WiFi NAT PPPoS |=== UART / SPI / SDIO / ETH ===| PPPoS client   |
+         |        (server)|                               |                |
+         +----------------+                               +----------------+
 ```
 
+## Features
+
+### Network Interface Modes
+
+Standard PPP Mode (where PPP protocols is preferred) or simple tunnel using TUN Mode.
+
+### Transport layer
+
+UART, SPI, SDIO, Ethernet
+
+### Support for logical channels
+
+Allows channeling custom data (e.g. 802.11 frames)
+
+## (Other) usecases
+
+Besides the communication coprocessor example mentioned above, this component could be used to:
+* Bring Wi-Fi connectivity to a computer using ESP32 chip.
+* Connect your microcontroller to the internet via a pppd server (running on a raspberry)
+* Bridging two networks with two microcontrollers
+
+## Configuration
+
+### Choose the transport layer
+
+Use `idf.py menuconfig` to select the transport layer:
+
+* `CONFIG_EPPP_LINK_UART` -- Use UART transport layer
+* `CONFIG_EPPP_LINK_SPI` -- Use SPI transport layer
+* `CONFIG_EPPP_LINK_SDIO` -- Use SDIO transport layer
+* `CONFIG_EPPP_LINK_ETHERNET` -- Use Ethernet transport
+  - Note: Ethernet creates it's own task, so calling `eppp_perform()` would not work
+  - Note: Add dependency to ethernet_init component to use other Ethernet drivers
+  - Note: You can override functions `eppp_transport_ethernet_deinit()` and `eppp_transport_ethernet_init()` to use your own Ethernet driver
+
+### Choose the network interface
+
+Use PPP netif for UART; Keep the default (TUN) for others
+
+### Channel support (multiple logical channels)
+
+* `CONFIG_EPPP_LINK_CHANNELS_SUPPORT` -- Enable support for multiple logical channels (default: disabled)
+* `CONFIG_EPPP_LINK_NR_OF_CHANNELS` -- Number of logical channels (default: 2, range: 1-8, only visible if channel support is enabled)
+
+When channel support is enabled, the EPPP link can multiplex multiple logical data streams over the same transport. The number of channels is configurable. Channel support is not available for Ethernet transport.
+
+To use channels in your application, use the `eppp_add_channels()` API and provide your own channel transmit/receive callbacks. These APIs and related types are only available when channel support is enabled in Kconfig.
+
 ## API
 
 ### Client
@@ -36,6 +86,9 @@ brings in the WiFi connectivity from the "SLAVE" microcontroller.
 * `eppp_netif_start()` -- Starts the network, could be called after startup or whenever a connection is lost
 * `eppp_netif_stop()` --  Stops the network
 * `eppp_perform()` -- Perform one iteration of the PPP task (need to be called regularly in task-less configuration)
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+* `eppp_add_channels()` -- Register channel transmit/receive callbacks (only available if channel support is enabled)
+#endif
 
 ## Throughput
 
@@ -55,3 +108,9 @@ Tested with WiFi-NAPT example
 
 * TCP - 9Mbits/s
 * UDP - 11Mbits/s
+
+### Ethernet
+
+- Internal EMAC with real PHY chip
+    * TCP - 5Mbits/s
+    * UDP - 8Mbits/s

components/eppp_link/detailed_description.md

@@ -0,0 +1,370 @@
+# ESP PPP Link Component (eppp_link) - Detailed Documentation
+
+## Overview
+
+The ESP PPP Link component provides a versatile communication bridge between two ESP32 microcontrollers, enabling network connectivity over various physical transport layers. One device acts as a server (typically providing connectivity), while the other acts as a client (consuming connectivity).
+
+## Network Interface Modes
+
+### PPP Mode vs TUN Mode
+
+The component supports two distinct network interface modes:
+
+#### PPP Mode (`CONFIG_EPPP_LINK_USES_PPP=y`)
+- **Standard PPP Protocol**: Uses the Point-to-Point Protocol (RFC 1661) with full LCP negotiation
+- **Compatibility**: Compatible with standard PPP implementations like Linux `pppd`
+- **Features**:
+  - Automatic IP address negotiation
+  - Link Control Protocol (LCP) for connection establishment
+  - Authentication support (if configured)
+  - Standard PPP framing with escape sequences
+- **Use Case**: When interfacing with standard PPP-capable systems or when full PPP compatibility is required
+- **Transport Limitation**: Primarily designed for UART transport due to PPP's serial nature
+
+#### TUN Mode (`CONFIG_EPPP_LINK_USES_PPP=n`, default)
+- **Simplified Packet Interface**: Uses a custom packet-based protocol without PPP negotiation
+- **Performance**: Faster data transfer due to reduced protocol overhead
+- **Features**:
+  - Direct IP packet transmission
+  - Custom framing for packet boundaries
+  - No negotiation overhead
+  - Static IP address configuration
+- **Use Case**: Default mode for ESP-to-ESP communication, optimal for non-UART transports
+- **Transport Support**: Works efficiently with all transport types (UART, SPI, SDIO, Ethernet)
+
+**Mode Selection**: Configure via `idf.py menuconfig` → `Component config` → `eppp_link` → `Use PPP network interface`
+
+## Transport Layer Options
+
+### UART Transport
+- **Configuration**: `CONFIG_EPPP_LINK_DEVICE_UART=y`
+- **Features**:
+  - Simple serial communication
+  - Configurable baud rate (up to 3Mbps tested)
+  - Hardware flow control support
+  - Custom framing for packet boundaries in TUN mode
+- **Performance**: ~2 Mbps (TCP/UDP) @ 3 Mbaud
+- **Use Case**: Basic connectivity, long-distance communication, debugging
+- **Pins**: TX, RX configurable
+
+```c
+eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+config.transport = EPPP_TRANSPORT_UART;
+config.uart.tx_io = 25;
+config.uart.rx_io = 26;
+config.uart.baud = 921600;
+```
+
+### SPI Transport
+- **Configuration**: `CONFIG_EPPP_LINK_DEVICE_SPI=y`
+- **Features**:
+  - Master/slave configuration
+  - GPIO interrupt signaling for flow control
+  - Configurable clock frequency
+  - Full-duplex communication
+  - Packet queue for transmission
+- **Performance**: ~5 Mbps (TCP), ~8 Mbps (UDP) @ 16MHz
+- **Use Case**: High-speed local communication, PCB-level connections
+- **Pins**: MOSI, MISO, SCLK, CS, interrupt GPIO
+
+```c
+eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+config.transport = EPPP_TRANSPORT_SPI;
+config.spi.is_master = true;
+config.spi.freq = 16000000;
+config.spi.mosi = 11;
+config.spi.miso = 13;
+config.spi.sclk = 12;
+config.spi.cs = 10;
+config.spi.intr = 2;
+```
+
+### SDIO Transport
+- **Configuration**: `CONFIG_EPPP_LINK_DEVICE_SDIO=y`
+- **Features**:
+  - Host/slave configuration
+  - High-speed data transfer
+  - 1-bit or 4-bit bus width
+  - Hardware flow control
+- **Performance**: ~9 Mbps (TCP), ~11 Mbps (UDP)
+- **Use Case**: Highest throughput applications, module-to-module communication
+- **Pins**: CLK, CMD, D0-D3 (configurable width)
+
+```c
+eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+config.transport = EPPP_TRANSPORT_SDIO;
+config.sdio.is_host = true;
+config.sdio.width = 4;
+config.sdio.clk = 18;
+config.sdio.cmd = 19;
+config.sdio.d0 = 14;
+// ... additional data pins
+```
+
+### Ethernet Transport
+- **Configuration**: `CONFIG_EPPP_LINK_DEVICE_ETH=y`
+- **Features**:
+  - Direct MAC-to-MAC communication
+  - Can work with or without PHY chips
+  - Standard Ethernet framing
+  - Automatic task management (no `eppp_perform()` needed)
+- **Performance**: ~5 Mbps (TCP), ~8 Mbps (UDP) with internal EMAC
+- **Use Case**: Board-to-board communication, integration with existing Ethernet infrastructure
+- **Pins**: MDC, MDIO, plus PHY-specific pins
+
+```c
+eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+config.transport = EPPP_TRANSPORT_ETHERNET;
+config.ethernet.mdc_io = 23;
+config.ethernet.mdio_io = 18;
+config.ethernet.phy_addr = 1;
+config.ethernet.rst_io = 5;
+```
+
+## Channel Support (Multiple Logical Channels)
+
+### Overview
+Channel support allows multiplexing multiple independent data streams over a single transport connection. This enables applications to separate different types of data (e.g., network traffic, control commands, sensor data) into distinct logical channels.
+
+### Configuration
+- **Enable**: `CONFIG_EPPP_LINK_CHANNELS_SUPPORT=y`
+- **Count**: `CONFIG_EPPP_LINK_NR_OF_CHANNELS` (1-8 channels, default 2)
+- **Limitation**: Not available for Ethernet transport
+
+### Channel Usage
+```c
+// Channel callback function type
+typedef esp_err_t (*eppp_channel_fn_t)(esp_netif_t *netif, int nr, void *buffer, size_t len);
+
+// Register channel callbacks
+esp_err_t eppp_add_channels(esp_netif_t *netif,
+                           eppp_channel_fn_t *tx,     // Transmit function pointer (output)
+                           const eppp_channel_fn_t rx, // Receive callback (input)
+                           void* context);             // User context
+
+// Get user context
+void* eppp_get_context(esp_netif_t *netif);
+```
+
+### Channel Example
+```c
+// Channel 0: Default network traffic (handled automatically)
+// Channel 1: Control/chat messages
+// Channel 2: WiFi data forwarding
+
+static esp_err_t channel_receive(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    switch(channel) {
+        case 1: // Control channel
+            process_control_message(buffer, len);
+            break;
+        case 2: // WiFi channel
+            forward_to_wifi(buffer, len);
+            break;
+        default:
+            ESP_LOGE(TAG, "Unknown channel %d", channel);
+            return ESP_FAIL;
+    }
+    return ESP_OK;
+}
+
+// Register channels
+eppp_channel_fn_t tx_func;
+eppp_add_channels(netif, &tx_func, channel_receive, user_context);
+
+// Transmit on specific channel
+tx_func(netif, 1, "Hello", 5);  // Send to channel 1
+```
+
+## API Reference
+
+### Simple API (Recommended for most use cases)
+
+#### Client Side
+```c
+esp_netif_t *eppp_connect(eppp_config_t *config);
+```
+- **Purpose**: Simplified client connection
+- **Behavior**: Blocks until connection is established
+- **Returns**: Configured network interface or NULL on failure
+- **Use Case**: Simple applications that don't need fine-grained control
+
+#### Server Side
+```c
+esp_netif_t *eppp_listen(eppp_config_t *config);
+```
+- **Purpose**: Simplified server listening
+- **Behavior**: Blocks until client connects
+- **Returns**: Configured network interface or NULL on failure
+- **Use Case**: Simple applications that don't need fine-grained control
+
+#### Connection Management
+```c
+void eppp_close(esp_netif_t *netif);
+```
+- **Purpose**: Close connection and cleanup resources
+- **Behavior**: Stops tasks, closes transport, destroys network interface
+
+### Advanced API (Manual Control)
+
+#### Initialization
+```c
+esp_netif_t *eppp_init(eppp_type_t role, eppp_config_t *config);
+```
+- **Purpose**: Initialize endpoint without starting communication
+- **Parameters**:
+  - `role`: `EPPP_SERVER` or `EPPP_CLIENT`
+  - `config`: Transport and network configuration
+- **Returns**: Network interface handle
+- **Use Case**: Applications needing manual control over connection lifecycle
+
+#### Connection Control
+```c
+esp_err_t eppp_netif_start(esp_netif_t *netif);
+esp_err_t eppp_netif_stop(esp_netif_t *netif, int stop_timeout_ms);
+```
+- **Purpose**: Manual network interface start/stop
+- **Use Case**: Dynamic connection management, error recovery
+
+#### Task Management
+```c
+esp_err_t eppp_perform(esp_netif_t *netif);
+```
+- **Purpose**: Single iteration of communication task
+- **Returns**:
+  - `ESP_OK`: Continue operation
+  - `ESP_FAIL`: Operation failed but should continue
+  - `ESP_ERR_TIMEOUT`: Stop operation requested
+- **Use Case**: Task-less operation, integration with custom task schedulers
+- **Note**: Not needed for Ethernet transport (has its own task)
+
+#### Resource Management
+```c
+void eppp_deinit(esp_netif_t *netif);
+```
+- **Purpose**: Clean up resources without stopping tasks
+- **Use Case**: Manual resource management
+
+## Configuration Examples
+
+### Basic Client-Server Setup
+
+**Client (Host) Configuration:**
+```c
+void app_main(void)
+{
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+    config.transport = EPPP_TRANSPORT_UART;
+    config.uart.tx_io = 25;
+    config.uart.rx_io = 26;
+    config.uart.baud = 921600;
+
+    esp_netif_t *netif = eppp_connect(&config);
+    if (netif == NULL) {
+        ESP_LOGE(TAG, "Failed to connect");
+        return;
+    }
+
+    ESP_LOGI(TAG, "Connected successfully");
+    // Use network interface for communication
+}
+```
+
+**Server (Slave) Configuration:**
+```c
+void app_main(void)
+{
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    // Initialize WiFi or other network interface
+    init_wifi();
+
+    eppp_config_t config = EPPP_DEFAULT_SERVER_CONFIG();
+    config.transport = EPPP_TRANSPORT_UART;
+    config.uart.tx_io = 26;  // Crossed with client
+    config.uart.rx_io = 25;  // Crossed with client
+    config.uart.baud = 921600;
+
+    esp_netif_t *netif = eppp_listen(&config);
+    if (netif == NULL) {
+        ESP_LOGE(TAG, "Failed to setup server");
+        return;
+    }
+
+    // Enable NAT to share WiFi connection
+    ESP_ERROR_CHECK(esp_netif_napt_enable(netif));
+    ESP_LOGI(TAG, "Server ready");
+}
+```
+
+### Advanced Manual Control
+```c
+void app_main(void)
+{
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+    config.task.run_task = false;  // Disable automatic task
+
+    esp_netif_t *netif = eppp_init(EPPP_CLIENT, &config);
+    if (netif == NULL) {
+        ESP_LOGE(TAG, "Failed to initialize");
+        return;
+    }
+
+    // Start network interface
+    ESP_ERROR_CHECK(eppp_netif_start(netif));
+
+    // Custom task loop
+    while (true) {
+        esp_err_t ret = eppp_perform(netif);
+        if (ret == ESP_ERR_TIMEOUT) {
+            ESP_LOGI(TAG, "Operation stopped");
+            break;
+        } else if (ret != ESP_OK) {
+            ESP_LOGE(TAG, "Operation failed: %s", esp_err_to_name(ret));
+        }
+
+        // Add custom processing here
+        vTaskDelay(pdMS_TO_TICKS(1));
+    }
+
+    eppp_deinit(netif);
+}
+```
+
+### Multi-Channel Configuration
+```c
+typedef struct {
+    eppp_channel_fn_t tx_func;
+    esp_netif_t *netif;
+} channel_context_t;
+
+static esp_err_t channel_rx(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    ESP_LOGI(TAG, "Channel %d received %d bytes", channel, len);
+    // Process channel data based on channel number
+    return ESP_OK;
+}
+
+void setup_channels(void)
+{
+    eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+    esp_netif_t *netif = eppp_connect(&config);
+
+    channel_context_t *ctx = calloc(1, sizeof(channel_context_t));
+    ctx->netif = netif;
+
+    // Register channel callbacks
+    ESP_ERROR_CHECK(eppp_add_channels(netif, &ctx->tx_func, channel_rx, ctx));
+
+    // Send data on channel 1
+    const char *msg = "Hello on channel 1";
+    ctx->tx_func(netif, 1, (void*)msg, strlen(msg));
+}
+```

components/eppp_link/eppp_eth.c

@@ -0,0 +1,210 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <string.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include "esp_log.h"
+#include "esp_netif.h"
+#include "esp_check.h"
+#include "esp_event.h"
+#include "esp_mac.h"
+#include "esp_idf_version.h"
+#include "eppp_link.h"
+#include "eppp_transport.h"
+#include "esp_eth_driver.h"
+#include "esp_eth_spec.h"
+#include "eppp_transport_eth.h"
+// Use Ethernet Init component if available
+// (otherwise use just simple init/deinit with generic MAC/PHY)
+#if __has_include("ethernet_init.h")
+#define USE_ETHERNET_INIT_COMPONENT
+#include "ethernet_init.h"
+#endif
+
+typedef struct header {
+    uint8_t dst[ETH_ADDR_LEN];
+    uint8_t src[ETH_ADDR_LEN];
+    uint16_t len;
+} __attribute__((packed)) header_t;
+
+static const char *TAG = "eppp_ethernet";
+static bool s_is_connected = false;
+static esp_eth_handle_t *s_eth_handles = NULL;
+static uint8_t s_their_mac[ETH_ADDR_LEN];
+static uint8_t s_our_mac[ETH_ADDR_LEN];
+
+#ifndef USE_ETHERNET_INIT_COMPONENT
+static esp_eth_handle_t s_handles[1] = { NULL };
+static esp_eth_mac_t *s_mac = NULL;
+static esp_eth_phy_t *s_phy = NULL;
+
+static void simple_deinit(esp_eth_handle_t *handle_array[])
+{
+    if (s_handles[0] != NULL) {
+        esp_eth_driver_uninstall(s_handles[0]);
+        s_handles[0] = NULL;
+    }
+    if (s_mac != NULL) {
+        s_mac->del(s_mac);
+        s_mac = NULL;
+    }
+    if (s_phy != NULL) {
+        s_phy->del(s_phy);
+        s_phy = NULL;
+    }
+}
+
+static esp_err_t simple_init(struct eppp_config_ethernet_s *config, esp_eth_handle_t *handle_array[])
+{
+    esp_err_t ret = ESP_OK;
+    eth_mac_config_t mac_config = ETH_MAC_DEFAULT_CONFIG();
+    eth_esp32_emac_config_t esp32_emac_config = ETH_ESP32_EMAC_DEFAULT_CONFIG();
+    esp32_emac_config.smi_gpio.mdc_num = config->mdc_io;
+    esp32_emac_config.smi_gpio.mdio_num = config->mdio_io;
+    s_mac = esp_eth_mac_new_esp32(&esp32_emac_config, &mac_config);
+    eth_phy_config_t phy_config = ETH_PHY_DEFAULT_CONFIG();
+    phy_config.phy_addr = config->phy_addr;
+    phy_config.reset_gpio_num = config->rst_io;
+#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(5, 4, 0)
+    s_phy = esp_eth_phy_new_generic(&phy_config);
+#else
+    s_phy = esp_eth_phy_new_ip101(&phy_config);
+#endif
+    esp_eth_config_t eth_config = ETH_DEFAULT_CONFIG(s_mac, s_phy);
+    ESP_GOTO_ON_ERROR(esp_eth_driver_install(&eth_config, &s_handles[0]), err, TAG, "Ethernet driver install failed");
+    *handle_array = s_handles;
+    return ESP_OK;
+err:
+    simple_deinit(handle_array);
+    return ret;
+}
+
+#endif // USE_ETHERNET_INIT_COMPONENT
+
+static void event_handler(void *arg, esp_event_base_t event_base,
+                          int32_t event_id, void *event_data)
+{
+    switch (event_id) {
+    case ETHERNET_EVENT_CONNECTED:
+        ESP_LOGI(TAG, "Ethernet Link Up");
+        s_is_connected = true;
+        break;
+    case ETHERNET_EVENT_DISCONNECTED:
+        ESP_LOGI(TAG, "Ethernet Link Down");
+        s_is_connected = false;
+        break;
+    case ETHERNET_EVENT_START:
+        ESP_LOGI(TAG, "Ethernet Started");
+        break;
+    case ETHERNET_EVENT_STOP:
+        ESP_LOGI(TAG, "Ethernet Stopped");
+        break;
+    default:
+        break;
+    }
+}
+
+static esp_err_t receive(esp_eth_handle_t h, uint8_t *buffer, uint32_t len, void *netif)
+{
+    header_t *head = (header_t *)buffer;
+    size_t packet_len = head->len;
+    if (len >= packet_len) {
+        esp_err_t ret = esp_netif_receive(netif, buffer + ETH_HEADER_LEN, packet_len, NULL);
+        free(buffer);
+        return ret;
+    }
+    return ESP_FAIL;
+}
+
+__attribute__((weak)) esp_err_t eppp_transport_ethernet_init(struct eppp_config_ethernet_s *config, esp_eth_handle_t *handle_array[])
+{
+#ifdef USE_ETHERNET_INIT_COMPONENT
+    uint8_t eth_port_cnt = 0;
+    ESP_RETURN_ON_ERROR(ethernet_init_all(handle_array, &eth_port_cnt), TAG, "Failed to init common eth drivers");
+    ESP_RETURN_ON_FALSE(eth_port_cnt == 1, ESP_ERR_INVALID_ARG, TAG, "multiple Ethernet devices detected, please init only one");
+    return ESP_OK;
+#else
+    return simple_init(config, handle_array);
+#endif
+}
+
+__attribute__((weak)) void eppp_transport_ethernet_deinit(esp_eth_handle_t *handle_array[])
+{
+#ifdef USE_ETHERNET_INIT_COMPONENT
+    ethernet_deinit_all(s_eth_handles);
+#else
+    simple_deinit(handle_array);
+#endif
+}
+
+esp_err_t eppp_transport_tx(void *h, void *buffer, size_t len)
+{
+    static uint8_t out_buffer[ETH_HEADER_LEN];
+    if (!s_is_connected) {
+        return ESP_FAIL;
+    }
+    // setup Ethernet header
+    header_t *head = (header_t *)out_buffer;
+    memcpy(head->dst, s_their_mac, ETH_ADDR_LEN);
+    memcpy(head->src, s_our_mac, ETH_ADDR_LEN);
+    head->len = len;
+    // support only payloads with len <=  ETH_MAX_PAYLOAD_LEN
+    if (len > ETH_MAX_PAYLOAD_LEN) {
+        return ESP_FAIL;
+    }
+    return esp_eth_transmit_vargs(s_eth_handles[0], 2, out_buffer, ETH_HEADER_LEN, buffer, len);
+}
+
+static esp_err_t start_driver(esp_netif_t *esp_netif)
+{
+    ESP_RETURN_ON_ERROR(esp_eth_update_input_path(s_eth_handles[0], receive, esp_netif), TAG, "Failed to set Ethernet Rx callback");
+    sscanf(CONFIG_EPPP_LINK_ETHERNET_OUR_ADDRESS, "%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8,
+           &s_our_mac[0], &s_our_mac[1], &s_our_mac[2], &s_our_mac[3], &s_our_mac[4], &s_our_mac[5]);
+
+    sscanf(CONFIG_EPPP_LINK_ETHERNET_THEIR_ADDRESS, "%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8,
+           &s_their_mac[0], &s_their_mac[1], &s_their_mac[2], &s_their_mac[3], &s_their_mac[4], &s_their_mac[5]);
+    esp_eth_ioctl(s_eth_handles[0], ETH_CMD_S_MAC_ADDR, s_our_mac);
+    ESP_RETURN_ON_ERROR(esp_event_handler_register(ETH_EVENT, ESP_EVENT_ANY_ID, event_handler, NULL), TAG, "Failed to register Ethernet handlers");
+    ESP_RETURN_ON_ERROR(esp_eth_start(s_eth_handles[0]), TAG, "Failed to start Ethernet driver");
+    return ESP_OK;
+}
+
+static esp_err_t post_attach(esp_netif_t *esp_netif, void *args)
+{
+    eppp_transport_handle_t h = (eppp_transport_handle_t)args;
+    ESP_RETURN_ON_FALSE(h, ESP_ERR_INVALID_ARG, TAG, "Transport handle cannot be null");
+    h->base.netif = esp_netif;
+
+    esp_netif_driver_ifconfig_t driver_ifconfig = {
+        .handle =  h,
+        .transmit = eppp_transport_tx,
+    };
+
+    ESP_RETURN_ON_ERROR(esp_netif_set_driver_config(esp_netif, &driver_ifconfig), TAG, "Failed to set driver config");
+    ESP_LOGI(TAG, "EPPP Ethernet transport attached to EPPP netif %s", esp_netif_get_desc(esp_netif));
+    ESP_RETURN_ON_ERROR(start_driver(esp_netif), TAG, "Failed to start EPPP ethernet driver");
+    ESP_LOGI(TAG, "EPPP Ethernet driver started");
+    return ESP_OK;
+}
+
+eppp_transport_handle_t eppp_eth_init(struct eppp_config_ethernet_s *config)
+{
+    __attribute__((unused)) esp_err_t ret = ESP_OK;
+    ESP_RETURN_ON_FALSE(config, NULL, TAG, "Config cannot be null");
+    eppp_transport_handle_t h = calloc(1, sizeof(struct eppp_handle));
+    ESP_RETURN_ON_FALSE(h, NULL, TAG, "Failed to allocate eppp_handle");
+    ESP_GOTO_ON_ERROR(eppp_transport_ethernet_init(config, &s_eth_handles), err, TAG, "Failed to init Ethernet transport");
+    h->base.post_attach = post_attach;
+    return h;
+err:
+    return NULL;
+}
+
+void eppp_eth_deinit(eppp_transport_handle_t h)
+{
+    esp_eth_stop(s_eth_handles[0]);
+    eppp_transport_ethernet_deinit(&s_eth_handles);
+}

components/eppp_link/eppp_link.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2019-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2019-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -12,16 +12,17 @@
 #include "esp_event.h"
 #include "esp_netif_ppp.h"
 #include "eppp_link.h"
-#include "esp_serial_slave_link/essl_sdio.h"
+#include "eppp_transport_eth.h"
+#include "eppp_transport_spi.h"
+#include "eppp_transport_uart.h"
+#include "eppp_transport_sdio.h"
+#include "eppp_transport.h"
 
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-#include "driver/spi_master.h"
-#include "driver/spi_slave.h"
-#include "driver/gpio.h"
-#include "esp_timer.h"
-#include "esp_rom_crc.h"
-#elif CONFIG_EPPP_LINK_DEVICE_UART
-#include "driver/uart.h"
+
+#if CONFIG_EPPP_LINK_DEVICE_ETH
+#define EPPP_NEEDS_TASK 0
+#else
+#define EPPP_NEEDS_TASK 1
 #endif
 
 static const int GOT_IPV4 = BIT0;
@@ -33,204 +34,54 @@ static const char *TAG = "eppp_link";
 static int s_retry_num = 0;
 static int s_eppp_netif_count = 0; // used as a suffix for the netif key
 
-
-struct packet {
-    size_t len;
-    uint8_t *data;
-};
-
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-#define MAX_PAYLOAD 1500
-#define MIN_TRIGGER_US 20
-#define SPI_HEADER_MAGIC 0x1234
-
-static void timer_callback(void *arg);
-
-struct header {
-    uint16_t magic;
-    uint16_t size;
-    uint16_t next_size;
-    uint16_t check;
-} __attribute__((packed));
-
-enum blocked_status {
-    NONE,
-    MASTER_BLOCKED,
-    MASTER_WANTS_READ,
-    SLAVE_BLOCKED,
-    SLAVE_WANTS_WRITE,
-};
-
-#endif // CONFIG_EPPP_LINK_DEVICE_SPI
-
-struct eppp_handle {
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-    QueueHandle_t out_queue;
-    QueueHandle_t ready_semaphore;
-    spi_device_handle_t spi_device;
-    spi_host_device_t spi_host;
-    int gpio_intr;
-    uint16_t next_size;
-    uint16_t transaction_size;
-    struct packet outbound;
-    enum blocked_status blocked;
-    uint32_t slave_last_edge;
-    esp_timer_handle_t timer;
-#elif CONFIG_EPPP_LINK_DEVICE_UART
-    QueueHandle_t uart_event_queue;
-    uart_port_t uart_port;
-#endif
-    esp_netif_t *netif;
-    eppp_type_t role;
-    bool stop;
-    bool exited;
-    bool netif_stop;
-};
-
-typedef esp_err_t (*transmit_t)(void *h, void *buffer, size_t len);
-
-#if CONFIG_EPPP_LINK_DEVICE_SDIO
-esp_err_t eppp_sdio_host_tx(void *h, void *buffer, size_t len);
-esp_err_t eppp_sdio_host_rx(esp_netif_t *netif);
-esp_err_t eppp_sdio_slave_rx(esp_netif_t *netif);
-esp_err_t eppp_sdio_slave_tx(void *h, void *buffer, size_t len);
-esp_err_t eppp_sdio_host_init(struct eppp_config_sdio_s *config);
-esp_err_t eppp_sdio_slave_init(void);
-void eppp_sdio_slave_deinit(void);
-void eppp_sdio_host_deinit(void);
-#else
-static esp_err_t transmit(void *h, void *buffer, size_t len)
-{
-    struct eppp_handle *handle = h;
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-    struct packet buf = { };
-    uint8_t *current_buffer = buffer;
-    size_t remaining = len;
-    do {    // TODO(IDF-9194): Refactor this loop to allocate only once and perform
-        //       fragmentation after receiving from the queue (applicable only if MTU > MAX_PAYLOAD)
-        size_t batch = remaining > MAX_PAYLOAD ? MAX_PAYLOAD : remaining;
-        buf.data = malloc(batch);
-        if (buf.data == NULL) {
-            ESP_LOGE(TAG, "Failed to allocate packet");
-            return ESP_ERR_NO_MEM;
-        }
-        buf.len = batch;
-        remaining -= batch;
-        memcpy(buf.data, current_buffer, batch);
-        current_buffer += batch;
-        BaseType_t ret = xQueueSend(handle->out_queue, &buf, 0);
-        if (ret != pdTRUE) {
-            ESP_LOGE(TAG, "Failed to queue packet to slave!");
-            return ESP_ERR_NO_MEM;
-        }
-    } while (remaining > 0);
-
-    if (handle->role == EPPP_SERVER && handle->blocked == SLAVE_BLOCKED) {
-        uint32_t now = esp_timer_get_time();
-        uint32_t diff = now - handle->slave_last_edge;
-        if (diff < MIN_TRIGGER_US) {
-            esp_rom_delay_us(MIN_TRIGGER_US - diff);
-        }
-        gpio_set_level(handle->gpio_intr, 0);
-    }
-
-#elif CONFIG_EPPP_LINK_DEVICE_UART
-    ESP_LOG_BUFFER_HEXDUMP("ppp_uart_send", buffer, len, ESP_LOG_VERBOSE);
-    uart_write_bytes(handle->uart_port, buffer, len);
-#endif // DEVICE UART or SPI
-    return ESP_OK;
-}
-#endif
-
-static void netif_deinit(esp_netif_t *netif)
+void eppp_netif_deinit(esp_netif_t *netif)
 {
     if (netif == NULL) {
         return;
     }
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    if (h == NULL) {
-        return;
-    }
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-    struct packet buf = { };
-    while (xQueueReceive(h->out_queue, &buf, 0) == pdTRUE) {
-        if (buf.len > 0) {
-            free(buf.data);
-        }
-    }
-    vQueueDelete(h->out_queue);
-    if (h->role == EPPP_CLIENT) {
-        vSemaphoreDelete(h->ready_semaphore);
-    }
-#endif
-    free(h);
     esp_netif_destroy(netif);
     if (s_eppp_netif_count > 0) {
         s_eppp_netif_count--;
     }
 }
 
-static esp_netif_t *netif_init(eppp_type_t role, eppp_config_t *eppp_config)
+#ifdef CONFIG_EPPP_LINK_USES_PPP
+#define NETSTACK_CONFIG() ESP_NETIF_NETSTACK_DEFAULT_PPP
+#else
+#define NETSTACK_CONFIG() g_eppp_netif_config_tun
+extern esp_netif_netstack_config_t *g_eppp_netif_config_tun;
+#define ESP_NETIF_INHERENT_DEFAULT_SLIP() \
+    {   \
+        ESP_COMPILER_DESIGNATED_INIT_AGGREGATE_TYPE_EMPTY(mac) \
+        ESP_COMPILER_DESIGNATED_INIT_AGGREGATE_TYPE_EMPTY(ip_info) \
+        .flags = ESP_NETIF_FLAG_EVENT_IP_MODIFIED,              \
+        .get_ip_event = IP_EVENT_PPP_GOT_IP,    \
+        .lost_ip_event = IP_EVENT_PPP_LOST_IP,   \
+        .if_key = "EPPP_TUN",  \
+        .if_desc = "eppp",    \
+        .route_prio = 1,     \
+        .bridge_info = NULL \
+};
+#endif // CONFIG_EPPP_LINK_USES_PPP
+
+esp_netif_t *eppp_netif_init(eppp_type_t role, eppp_transport_handle_t h, eppp_config_t *eppp_config)
 {
     if (s_eppp_netif_count > 9) {   // Limit to max 10 netifs, since we use "EPPPx" as the unique key (where x is 0-9)
         ESP_LOGE(TAG, "Cannot create more than 10 instances");
         return NULL;
     }
 
-    // Create the object first
-    struct eppp_handle *h = calloc(1, sizeof(struct eppp_handle));
-    if (!h) {
-        ESP_LOGE(TAG, "Failed to allocate eppp_handle");
-        return NULL;
-    }
     h->role = role;
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-    h->out_queue = xQueueCreate(CONFIG_EPPP_LINK_PACKET_QUEUE_SIZE, sizeof(struct packet));
-    if (!h->out_queue) {
-        ESP_LOGE(TAG, "Failed to create the packet queue");
-        free(h);
-        return NULL;
-    }
-    if (role == EPPP_CLIENT) {
-        h->ready_semaphore = xSemaphoreCreateBinary();
-        if (!h->ready_semaphore) {
-            ESP_LOGE(TAG, "Failed to create the packet queue");
-            vQueueDelete(h->out_queue);
-            free(h);
-            return NULL;
-        }
-    }
-    h->transaction_size = 0;
-    h->outbound.data = NULL;
-    h->outbound.len = 0;
-    if (role == EPPP_SERVER) {
-        esp_timer_create_args_t args = {
-            .callback = &timer_callback,
-            .arg = h,
-            .name = "timer"
-        };
-        if (esp_timer_create(&args, &h->timer) != ESP_OK) {
-            ESP_LOGE(TAG, "Failed to create the packet queue");
-            vQueueDelete(h->out_queue);
-            vSemaphoreDelete(h->ready_semaphore);
-            free(h);
-            return NULL;
-        }
-    }
-
-#endif
-
-    esp_netif_driver_ifconfig_t driver_cfg = {
-        .handle = h,
-#if CONFIG_EPPP_LINK_DEVICE_SDIO
-        .transmit = role == EPPP_CLIENT ? eppp_sdio_host_tx : eppp_sdio_slave_tx,
-#else
-        .transmit = transmit,
-#endif
-    };
-    const esp_netif_driver_ifconfig_t *ppp_driver_cfg = &driver_cfg;
-
+#ifdef CONFIG_EPPP_LINK_USES_PPP
     esp_netif_inherent_config_t base_netif_cfg = ESP_NETIF_INHERENT_DEFAULT_PPP();
+#else
+    esp_netif_inherent_config_t base_netif_cfg = ESP_NETIF_INHERENT_DEFAULT_SLIP();
+    esp_netif_ip_info_t slip_ip4 = {};
+    slip_ip4.ip.addr = eppp_config->ppp.our_ip4_addr.addr;
+    slip_ip4.gw.addr = eppp_config->ppp.their_ip4_addr.addr;
+    slip_ip4.netmask.addr = ESP_IP4TOADDR(255, 255, 255, 0);
+    base_netif_cfg.ip_info = &slip_ip4;
+#endif
     char if_key[] = "EPPP0"; // netif key needs to be unique
     if_key[sizeof(if_key) - 2 /* 2 = two chars before the terminator */ ] += s_eppp_netif_count++;
     base_netif_cfg.if_key = if_key;
@@ -242,25 +93,27 @@ static esp_netif_t *netif_init(eppp_type_t role, eppp_config_t *eppp_config)
     if (eppp_config->ppp.netif_prio) {
         base_netif_cfg.route_prio = eppp_config->ppp.netif_prio;
     }
-    esp_netif_config_t netif_ppp_config = { .base = &base_netif_cfg,
-                                            .driver = ppp_driver_cfg,
-                                            .stack = ESP_NETIF_NETSTACK_DEFAULT_PPP
-                                          };
+    esp_netif_config_t netif_config = { .base = &base_netif_cfg,
+                                        .driver = NULL,
+                                        .stack = NETSTACK_CONFIG(),
+                                      };
 
-    esp_netif_t *netif = esp_netif_new(&netif_ppp_config);
-    if (!netif) {
-        ESP_LOGE(TAG, "Failed to create esp_netif");
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-        vQueueDelete(h->out_queue);
-        if (h->ready_semaphore) {
-            vSemaphoreDelete(h->ready_semaphore);
-        }
-#endif
-        free(h);
-        return NULL;
-    }
+#ifdef CONFIG_EPPP_LINK_USES_PPP
+    __attribute__((unused)) esp_err_t ret = ESP_OK;
+    esp_netif_t *netif = esp_netif_new(&netif_config);
+    esp_netif_ppp_config_t netif_params;
+    ESP_GOTO_ON_ERROR(esp_netif_ppp_get_params(netif, &netif_params), err, TAG, "Failed to get PPP params");
+    netif_params.ppp_our_ip4_addr = eppp_config->ppp.our_ip4_addr;
+    netif_params.ppp_their_ip4_addr = eppp_config->ppp.their_ip4_addr;
+    netif_params.ppp_error_event_enabled = true;
+    ESP_GOTO_ON_ERROR(esp_netif_ppp_set_params(netif, &netif_params), err, TAG, "Failed to set PPP params");
     return netif;
-
+err:
+    esp_netif_destroy(netif);
+    return NULL;
+#else
+    return esp_netif_new(&netif_config);
+#endif // CONFIG_EPPP_LINK_USES_PPP
 }
 
 esp_err_t eppp_netif_stop(esp_netif_t *netif, int stop_timeout_ms)
@@ -285,7 +138,12 @@ esp_err_t eppp_netif_start(esp_netif_t *netif)
 {
     esp_netif_action_start(netif, 0, 0, 0);
     esp_netif_action_connected(netif, 0, 0, 0);
+#ifndef CONFIG_EPPP_LINK_USES_PPP
+    // PPP provides address negotiation, if not PPP, we need to check connection manually
+    return eppp_check_connection(netif);
+#else
     return ESP_OK;
+#endif
 }
 
 static int get_netif_num(esp_netif_t *netif)
@@ -305,16 +163,17 @@ static int get_netif_num(esp_netif_t *netif)
     return  netif_cnt;
 }
 
+#ifdef CONFIG_EPPP_LINK_USES_PPP
 static void on_ppp_event(void *arg, esp_event_base_t base, int32_t event_id, void *data)
 {
     esp_netif_t **netif = data;
-    ESP_LOGD(TAG, "PPP status event: %" PRId32, event_id);
     if (base == NETIF_PPP_STATUS && event_id == NETIF_PPP_ERRORUSER) {
         ESP_LOGI(TAG, "Disconnected %d", get_netif_num(*netif));
         struct eppp_handle *h = esp_netif_get_io_driver(*netif);
         h->netif_stop = true;
     }
 }
+#endif // CONFIG_EPPP_LINK_USES_PPP
 
 static void on_ip_event(void *arg, esp_event_base_t base, int32_t event_id, void *data)
 {
@@ -341,356 +200,7 @@ static void on_ip_event(void *arg, esp_event_base_t base, int32_t event_id, void
     }
 }
 
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-
-#define SPI_ALIGN(size) (((size) + 3U) & ~(3U))
-#define TRANSFER_SIZE SPI_ALIGN((MAX_PAYLOAD + 6))
-#define NEXT_TRANSACTION_SIZE(a,b) (((a)>(b))?(a):(b)) /* next transaction: whichever is bigger */
-
-static void IRAM_ATTR timer_callback(void *arg)
-{
-    struct eppp_handle *h = arg;
-    if (h->blocked == SLAVE_WANTS_WRITE) {
-        gpio_set_level(h->gpio_intr, 0);
-    }
-}
-
-static void IRAM_ATTR gpio_isr_handler(void *arg)
-{
-    static uint32_t s_last_time;
-    uint32_t now = esp_timer_get_time();
-    uint32_t diff = now - s_last_time;
-    if (diff < MIN_TRIGGER_US) { // debounce
-        return;
-    }
-    s_last_time = now;
-    struct eppp_handle *h = arg;
-    BaseType_t yield = false;
-
-    // Positive edge means SPI slave prepared the data
-    if (gpio_get_level(h->gpio_intr) == 1) {
-        xSemaphoreGiveFromISR(h->ready_semaphore, &yield);
-        if (yield) {
-            portYIELD_FROM_ISR();
-        }
-        return;
-    }
-
-    // Negative edge (when master blocked) means that slave wants to transmit
-    if (h->blocked == MASTER_BLOCKED) {
-        struct packet buf = { .data = NULL, .len = -1 };
-        xQueueSendFromISR(h->out_queue, &buf, &yield);
-        if (yield) {
-            portYIELD_FROM_ISR();
-        }
-    }
-}
-
-static esp_err_t deinit_master(esp_netif_t *netif)
-{
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    ESP_RETURN_ON_ERROR(spi_bus_remove_device(h->spi_device), TAG, "Failed to remove SPI bus");
-    ESP_RETURN_ON_ERROR(spi_bus_free(h->spi_host), TAG, "Failed to free SPI bus");
-    return ESP_OK;
-}
-
-static esp_err_t init_master(struct eppp_config_spi_s *config, esp_netif_t *netif)
-{
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    h->spi_host = config->host;
-    h->gpio_intr = config->intr;
-    spi_bus_config_t bus_cfg = {};
-    bus_cfg.mosi_io_num = config->mosi;
-    bus_cfg.miso_io_num = config->miso;
-    bus_cfg.sclk_io_num = config->sclk;
-    bus_cfg.quadwp_io_num = -1;
-    bus_cfg.quadhd_io_num = -1;
-    bus_cfg.max_transfer_sz = TRANSFER_SIZE;
-    bus_cfg.flags = 0;
-    bus_cfg.intr_flags = 0;
-
-    // TODO: Init and deinit SPI bus separately (per Kconfig?)
-    if (spi_bus_initialize(config->host, &bus_cfg, SPI_DMA_CH_AUTO) != ESP_OK) {
-        return ESP_FAIL;
-    }
-
-    spi_device_interface_config_t dev_cfg = {};
-    dev_cfg.clock_speed_hz = config->freq;
-    dev_cfg.mode = 0;
-    dev_cfg.spics_io_num = config->cs;
-    dev_cfg.cs_ena_pretrans = config->cs_ena_pretrans;
-    dev_cfg.cs_ena_posttrans = config->cs_ena_posttrans;
-    dev_cfg.duty_cycle_pos = 128;
-    dev_cfg.input_delay_ns = config->input_delay_ns;
-    dev_cfg.pre_cb = NULL;
-    dev_cfg.post_cb = NULL;
-    dev_cfg.queue_size = 3;
-
-    if (spi_bus_add_device(config->host, &dev_cfg, &h->spi_device) != ESP_OK) {
-        return ESP_FAIL;
-    }
-
-    //GPIO config for the handshake line.
-    gpio_config_t io_conf = {
-        .intr_type = GPIO_INTR_ANYEDGE,
-        .mode = GPIO_MODE_INPUT,
-        .pull_up_en = 1,
-        .pin_bit_mask = BIT64(config->intr),
-    };
-
-    gpio_config(&io_conf);
-    gpio_install_isr_service(0);
-    gpio_set_intr_type(config->intr, GPIO_INTR_ANYEDGE);
-    gpio_isr_handler_add(config->intr, gpio_isr_handler, esp_netif_get_io_driver(netif));
-    return ESP_OK;
-}
-
-static void post_setup(spi_slave_transaction_t *trans)
-{
-    struct eppp_handle *h = trans->user;
-    h->slave_last_edge = esp_timer_get_time();
-    gpio_set_level(h->gpio_intr, 1);
-    if (h->transaction_size == 0) { // If no transaction planned:
-        if (h->outbound.len == 0) { // we're blocked if we don't have any data
-            h->blocked = SLAVE_BLOCKED;
-        } else {
-            h->blocked = SLAVE_WANTS_WRITE; // we notify the master that we want to write
-            esp_timer_start_once(h->timer, MIN_TRIGGER_US);
-        }
-    }
-}
-
-static void post_trans(spi_slave_transaction_t *trans)
-{
-    struct eppp_handle *h = trans->user;
-    h->blocked = NONE;
-    gpio_set_level(h->gpio_intr, 0);
-}
-
-static esp_err_t deinit_slave(esp_netif_t *netif)
-{
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    ESP_RETURN_ON_ERROR(spi_slave_free(h->spi_host), TAG, "Failed to free SPI slave host");
-    ESP_RETURN_ON_ERROR(spi_bus_remove_device(h->spi_device), TAG, "Failed to remove SPI device");
-    ESP_RETURN_ON_ERROR(spi_bus_free(h->spi_host), TAG, "Failed to free SPI bus");
-    return ESP_OK;
-}
-
-static esp_err_t init_slave(struct eppp_config_spi_s *config, esp_netif_t *netif)
-{
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    h->spi_host = config->host;
-    h->gpio_intr = config->intr;
-    spi_bus_config_t bus_cfg = {};
-    bus_cfg.mosi_io_num = config->mosi;
-    bus_cfg.miso_io_num = config->miso;
-    bus_cfg.sclk_io_num = config->sclk;
-    bus_cfg.quadwp_io_num = -1;
-    bus_cfg.quadhd_io_num = -1;
-    bus_cfg.flags = 0;
-    bus_cfg.intr_flags = 0;
-
-    //Configuration for the SPI slave interface
-    spi_slave_interface_config_t slvcfg = {
-        .mode = 0,
-        .spics_io_num = config->cs,
-        .queue_size = 3,
-        .flags = 0,
-        .post_setup_cb = post_setup,
-        .post_trans_cb = post_trans,
-    };
-
-    //Configuration for the handshake line
-    gpio_config_t io_conf = {
-        .intr_type = GPIO_INTR_DISABLE,
-        .mode = GPIO_MODE_OUTPUT,
-        .pin_bit_mask = BIT64(config->intr),
-    };
-
-    gpio_config(&io_conf);
-    gpio_set_pull_mode(config->mosi, GPIO_PULLUP_ONLY);
-    gpio_set_pull_mode(config->sclk, GPIO_PULLUP_ONLY);
-    gpio_set_pull_mode(config->cs, GPIO_PULLUP_ONLY);
-
-    //Initialize SPI slave interface
-    if (spi_slave_initialize(config->host, &bus_cfg, &slvcfg, SPI_DMA_CH_AUTO) != ESP_OK) {
-        return ESP_FAIL;
-    }
-    return ESP_OK;
-}
-
-typedef esp_err_t (*perform_transaction_t)(struct eppp_handle *h, size_t len, const void *tx_buffer, void *rx_buffer);
-
-static esp_err_t perform_transaction_master(struct eppp_handle *h, size_t len, const void *tx_buffer, void *rx_buffer)
-{
-    spi_transaction_t t = {};
-    t.length = len * 8;
-    t.tx_buffer = tx_buffer;
-    t.rx_buffer = rx_buffer;
-    return spi_device_transmit(h->spi_device, &t);
-}
-
-static esp_err_t perform_transaction_slave(struct eppp_handle *h, size_t len, const void *tx_buffer, void *rx_buffer)
-{
-    spi_slave_transaction_t t = {};
-    t.user = h;
-    t.length = len * 8;
-    t.tx_buffer = tx_buffer;
-    t.rx_buffer = rx_buffer;
-    return spi_slave_transmit(h->spi_host, &t, portMAX_DELAY);
-}
-
-esp_err_t eppp_perform(esp_netif_t *netif)
-{
-    static WORD_ALIGNED_ATTR uint8_t out_buf[TRANSFER_SIZE] = {};
-    static WORD_ALIGNED_ATTR uint8_t in_buf[TRANSFER_SIZE] = {};
-
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-
-    // Perform transaction for master and slave
-    const perform_transaction_t perform_transaction = h->role == EPPP_CLIENT ? perform_transaction_master : perform_transaction_slave;
-
-    if (h->stop) {
-        return ESP_ERR_TIMEOUT;
-    }
-
-    BaseType_t tx_queue_stat;
-    bool allow_test_tx = false;
-    uint16_t next_tx_size = 0;
-    if (h->role == EPPP_CLIENT) {
-        // SPI MASTER only code
-        if (xSemaphoreTake(h->ready_semaphore, pdMS_TO_TICKS(1000)) != pdTRUE) {
-            // slave might not be ready, but maybe we just missed an interrupt
-            allow_test_tx = true;
-        }
-        if (h->outbound.len == 0 && h->transaction_size == 0 && h->blocked == NONE) {
-            h->blocked = MASTER_BLOCKED;
-            xQueueReceive(h->out_queue, &h->outbound, portMAX_DELAY);
-            h->blocked = NONE;
-            if (h->outbound.len == -1) {
-                h->outbound.len = 0;
-                h->blocked = MASTER_WANTS_READ;
-            }
-        } else if (h->blocked == MASTER_WANTS_READ) {
-            h->blocked = NONE;
-        }
-    }
-    struct header *head = (void *)out_buf;
-    if (h->outbound.len <= h->transaction_size && allow_test_tx == false) {
-        // sending outbound
-        head->size = h->outbound.len;
-        if (h->outbound.len > 0) {
-            memcpy(out_buf + sizeof(struct header), h->outbound.data, h->outbound.len);
-            free(h->outbound.data);
-            ESP_LOG_BUFFER_HEXDUMP(TAG, out_buf + sizeof(struct header), head->size, ESP_LOG_VERBOSE);
-            h->outbound.data = NULL;
-            h->outbound.len = 0;
-        }
-        do {
-            tx_queue_stat = xQueueReceive(h->out_queue, &h->outbound, 0);
-        } while (tx_queue_stat == pdTRUE && h->outbound.len == -1);
-        if (h->outbound.len == -1) { // used as a signal only, no actual data
-            h->outbound.len = 0;
-        }
-    } else {
-        // outbound is bigger, need to transmit in another transaction (keep this empty)
-        head->size = 0;
-    }
-    next_tx_size = head->next_size = h->outbound.len;
-    head->magic = SPI_HEADER_MAGIC;
-    head->check = esp_rom_crc16_le(0, out_buf, sizeof(struct header) - sizeof(uint16_t));
-    esp_err_t ret = perform_transaction(h, sizeof(struct header) + h->transaction_size, out_buf, in_buf);
-    if (ret != ESP_OK) {
-        ESP_LOGE(TAG, "spi_device_transmit failed");
-        h->transaction_size = 0; // need to start with HEADER only transaction
-        return ESP_FAIL;
-    }
-    head = (void *)in_buf;
-    uint16_t check = esp_rom_crc16_le(0, in_buf, sizeof(struct header) - sizeof(uint16_t));
-    if (check != head->check || head->magic != SPI_HEADER_MAGIC) {
-        h->transaction_size = 0; // need to start with HEADER only transaction
-        if (allow_test_tx) {
-            return ESP_OK;
-        }
-        ESP_LOGE(TAG, "Wrong checksum or magic");
-        return ESP_FAIL;
-    }
-    if (head->size > 0) {
-        ESP_LOG_BUFFER_HEXDUMP(TAG, in_buf + sizeof(struct header), head->size, ESP_LOG_VERBOSE);
-        esp_netif_receive(netif, in_buf + sizeof(struct header), head->size, NULL);
-    }
-    h->transaction_size = NEXT_TRANSACTION_SIZE(next_tx_size, head->next_size);
-    return ESP_OK;
-}
-
-#elif CONFIG_EPPP_LINK_DEVICE_UART
-#define BUF_SIZE (1024)
-
-static esp_err_t init_uart(struct eppp_handle *h, eppp_config_t *config)
-{
-    h->uart_port = config->uart.port;
-    uart_config_t uart_config = {};
-    uart_config.baud_rate = config->uart.baud;
-    uart_config.data_bits = UART_DATA_8_BITS;
-    uart_config.parity    = UART_PARITY_DISABLE;
-    uart_config.stop_bits = UART_STOP_BITS_1;
-    uart_config.flow_ctrl = UART_HW_FLOWCTRL_DISABLE;
-    uart_config.source_clk = UART_SCLK_DEFAULT;
-
-    ESP_RETURN_ON_ERROR(uart_driver_install(h->uart_port, config->uart.rx_buffer_size, 0, config->uart.queue_size, &h->uart_event_queue, 0), TAG, "Failed to install UART");
-    ESP_RETURN_ON_ERROR(uart_param_config(h->uart_port, &uart_config), TAG, "Failed to set params");
-    ESP_RETURN_ON_ERROR(uart_set_pin(h->uart_port, config->uart.tx_io, config->uart.rx_io, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE), TAG, "Failed to set UART pins");
-    ESP_RETURN_ON_ERROR(uart_set_rx_timeout(h->uart_port, 1), TAG, "Failed to set UART Rx timeout");
-    return ESP_OK;
-}
-
-static void deinit_uart(struct eppp_handle *h)
-{
-    uart_driver_delete(h->uart_port);
-}
-
-esp_err_t eppp_perform(esp_netif_t *netif)
-{
-    static uint8_t buffer[BUF_SIZE] = {};
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    uart_event_t event = {};
-    if (h->stop) {
-        return ESP_ERR_TIMEOUT;
-    }
-
-    if (xQueueReceive(h->uart_event_queue, &event, pdMS_TO_TICKS(100)) != pdTRUE) {
-        return ESP_OK;
-    }
-    if (event.type == UART_DATA) {
-        size_t len;
-        uart_get_buffered_data_len(h->uart_port, &len);
-        if (len) {
-            len = uart_read_bytes(h->uart_port, buffer, BUF_SIZE, 0);
-            ESP_LOG_BUFFER_HEXDUMP("ppp_uart_recv", buffer, len, ESP_LOG_VERBOSE);
-            esp_netif_receive(netif, buffer, len, NULL);
-        }
-    } else {
-        ESP_LOGW(TAG, "Received UART event: %d", event.type);
-    }
-    return ESP_OK;
-}
-#elif CONFIG_EPPP_LINK_DEVICE_SDIO
-
-esp_err_t eppp_perform(esp_netif_t *netif)
-{
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    if (h->stop) {
-        return ESP_ERR_TIMEOUT;
-    }
-    if (h->role == EPPP_SERVER) {
-        return eppp_sdio_slave_rx(netif);
-    } else {
-        return eppp_sdio_host_rx(netif);
-    }
-}
-
-#endif // CONFIG_EPPP_LINK_DEVICE_SPI / UART
-
+#if EPPP_NEEDS_TASK
 static void ppp_task(void *args)
 {
     esp_netif_t *netif = args;
@@ -699,6 +209,7 @@ static void ppp_task(void *args)
     h->exited = true;
     vTaskDelete(NULL);
 }
+#endif
 
 static bool have_some_eppp_netif(esp_netif_t *netif, void *ctx)
 {
@@ -709,11 +220,13 @@ static void remove_handlers(void)
 {
     esp_netif_t *netif = esp_netif_find_if(have_some_eppp_netif, NULL);
     if (netif == NULL) {
-        // if EPPP netif in the system, we cleanup the statics
+        // if EPPP netif in the system, we clean up the statics
         vEventGroupDelete(s_event_group);
         s_event_group = NULL;
         esp_event_handler_unregister(IP_EVENT, ESP_EVENT_ANY_ID, on_ip_event);
+#ifdef CONFIG_EPPP_LINK_USES_PPP
         esp_event_handler_unregister(NETIF_PPP_STATUS, ESP_EVENT_ANY_ID, on_ppp_event);
+#endif
     }
 }
 
@@ -722,67 +235,33 @@ void eppp_deinit(esp_netif_t *netif)
     if (netif == NULL) {
         return;
     }
-#if CONFIG_EPPP_LINK_DEVICE_SPI
     struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    if (h->role == EPPP_CLIENT) {
-        deinit_master(netif);
-    } else {
-        deinit_slave(netif);
-    }
-#elif CONFIG_EPPP_LINK_DEVICE_UART
-    deinit_uart(esp_netif_get_io_driver(netif));
-#elif CONFIG_EPPP_LINK_DEVICE_SDIO
-    struct eppp_handle *h = esp_netif_get_io_driver(netif);
-    if (h->role == EPPP_CLIENT) {
-        eppp_sdio_host_deinit();
-    } else {
-        eppp_sdio_slave_deinit();
-    }
-#endif
-    netif_deinit(netif);
+    EPPP_TRANSPORT_DEINIT(h);
+    eppp_netif_deinit(netif);
 }
 
 esp_netif_t *eppp_init(eppp_type_t role, eppp_config_t *config)
 {
+    __attribute__((unused)) esp_err_t ret = ESP_OK;
+    esp_netif_t *netif = NULL;
     if (config == NULL || (role != EPPP_SERVER && role != EPPP_CLIENT)) {
         ESP_LOGE(TAG, "Invalid configuration or role");
         return NULL;
     }
 
-    esp_netif_t *netif = netif_init(role, config);
-    if (!netif) {
-        ESP_LOGE(TAG, "Failed to initialize PPP netif");
-        return NULL;
-    }
-    esp_netif_ppp_config_t netif_params;
-    ESP_ERROR_CHECK(esp_netif_ppp_get_params(netif, &netif_params));
-    netif_params.ppp_our_ip4_addr = config->ppp.our_ip4_addr;
-    netif_params.ppp_their_ip4_addr = config->ppp.their_ip4_addr;
-    netif_params.ppp_error_event_enabled = true;
-    ESP_ERROR_CHECK(esp_netif_ppp_set_params(netif, &netif_params));
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-    if (role == EPPP_CLIENT) {
-        init_master(&config->spi, netif);
-    } else {
-        init_slave(&config->spi, netif);
-
-    }
-#elif CONFIG_EPPP_LINK_DEVICE_UART
-    init_uart(esp_netif_get_io_driver(netif), config);
-#elif CONFIG_EPPP_LINK_DEVICE_SDIO
-    esp_err_t ret;
-    if (role == EPPP_SERVER) {
-        ret = eppp_sdio_slave_init();
-    } else {
-        ret = eppp_sdio_host_init(&config->sdio);
-    }
-
-    if (ret != ESP_OK) {
-        ESP_LOGE(TAG, "Failed to initialize SDIO %d", ret);
-        return NULL;
-    }
-#endif
+    eppp_transport_handle_t h = EPPP_TRANSPORT_INIT(config);
+    ESP_GOTO_ON_FALSE(h, ESP_ERR_NO_MEM, err, TAG, "Failed to init EPPP transport");
+    ESP_GOTO_ON_FALSE(netif = eppp_netif_init(role, h, config), ESP_ERR_NO_MEM, err, TAG, "Failed to init EPPP netif");
+    ESP_GOTO_ON_ERROR(esp_netif_attach(netif, h), err, TAG, "Failed to attach netif to EPPP transport");
     return netif;
+err:
+    if (h) {
+        EPPP_TRANSPORT_DEINIT(h);
+    }
+    if (netif) {
+        eppp_netif_deinit(netif);
+    }
+    return NULL;
 }
 
 esp_netif_t *eppp_open(eppp_type_t role, eppp_config_t *config, int connect_timeout_ms)
@@ -821,11 +300,13 @@ esp_netif_t *eppp_open(eppp_type_t role, eppp_config_t *config, int connect_time
             remove_handlers();
             return NULL;
         }
+#ifdef CONFIG_EPPP_LINK_USES_PPP
         if (esp_event_handler_register(NETIF_PPP_STATUS, ESP_EVENT_ANY_ID, on_ppp_event, NULL) !=  ESP_OK) {
             ESP_LOGE(TAG, "Failed to register PPP status handler");
             remove_handlers();
             return NULL;
         }
+#endif // CONFIG_EPPP_LINK_USES_PPP
     }
     esp_netif_t *netif = eppp_init(role, config);
     if (!netif) {
@@ -834,12 +315,13 @@ esp_netif_t *eppp_open(eppp_type_t role, eppp_config_t *config, int connect_time
     }
 
     eppp_netif_start(netif);
-
+#if EPPP_NEEDS_TASK
     if (xTaskCreate(ppp_task, "ppp connect", config->task.stack_size, netif, config->task.priority, NULL) != pdTRUE) {
         ESP_LOGE(TAG, "Failed to create a ppp connection task");
         eppp_deinit(netif);
         return NULL;
     }
+#endif
     int netif_cnt = get_netif_num(netif);
     if (netif_cnt < 0) {
         eppp_close(netif);
@@ -885,3 +367,24 @@ void eppp_close(esp_netif_t *netif)
     eppp_deinit(netif);
     remove_handlers();
 }
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+esp_err_t eppp_add_channels(esp_netif_t *netif, eppp_channel_fn_t *tx, const eppp_channel_fn_t rx, void* context)
+{
+    ESP_RETURN_ON_FALSE(netif != NULL && tx != NULL && rx != NULL, ESP_ERR_INVALID_ARG, TAG, "Invalid arguments");
+    struct eppp_handle *h = esp_netif_get_io_driver(netif);
+    ESP_RETURN_ON_FALSE(h != NULL && h->channel_tx != NULL, ESP_ERR_INVALID_STATE, TAG, "Transport not initialized");
+    *tx = h->channel_tx;
+    h->channel_rx = rx;
+    h->context = context;
+    return ESP_OK;
+}
+
+void* eppp_get_context(esp_netif_t *netif)
+{
+    ESP_RETURN_ON_FALSE(netif != NULL, NULL, TAG, "Invalid netif");
+    struct eppp_handle *h = esp_netif_get_io_driver(netif);
+    ESP_RETURN_ON_FALSE(h != NULL, NULL, TAG, "EPPP Not initialized");
+    return h->context;
+}
+#endif

components/eppp_link/eppp_netif_tun.c

@@ -0,0 +1,207 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <string.h>
+#include <stdint.h>
+#include "sdkconfig.h"
+#include "esp_log.h"
+#include "esp_netif.h"
+#include "esp_netif_net_stack.h"
+#include "lwip/esp_netif_net_stack.h"
+#include "lwip/prot/ethernet.h"
+#include "lwip/inet.h"
+#include "lwip/sockets.h"
+#include "ping/ping_sock.h"
+#include "esp_check.h"
+#include "esp_idf_version.h"
+
+#if defined(CONFIG_ESP_NETIF_RECEIVE_REPORT_ERRORS)
+typedef esp_err_t esp_netif_recv_ret_t;
+#define ESP_NETIF_OPTIONAL_RETURN_CODE(expr) expr
+#else
+typedef void esp_netif_recv_ret_t;
+#define ESP_NETIF_OPTIONAL_RETURN_CODE(expr)
+#endif // CONFIG_ESP_NETIF_RECEIVE_REPORT_ERRORS
+
+static const char *TAG = "eppp_tun_netif";
+
+static esp_netif_recv_ret_t tun_input(void *h, void *buffer, unsigned int len, void *eb)
+{
+    __attribute__((unused)) esp_err_t ret = ESP_OK;
+    struct netif *netif = h;
+    struct pbuf *p = NULL;
+
+    ESP_LOG_BUFFER_HEXDUMP(TAG, buffer, len, ESP_LOG_VERBOSE);
+    // need to alloc extra space for the ETH header to support possible packet forwarding
+    ESP_GOTO_ON_FALSE(p = pbuf_alloc(PBUF_RAW, len + SIZEOF_ETH_HDR, PBUF_RAM), ESP_ERR_NO_MEM, err, TAG, "pbuf_alloc failed");
+    ESP_GOTO_ON_FALSE(pbuf_remove_header(p, SIZEOF_ETH_HDR) == 0, ESP_FAIL, err, TAG, "pbuf_remove_header failed");
+    memcpy(p->payload, buffer, len);
+    ESP_GOTO_ON_FALSE(netif->input(p, netif) == ERR_OK, ESP_FAIL, err, TAG, "failed to input packet to lwip");
+    return ESP_NETIF_OPTIONAL_RETURN_CODE(ESP_OK);
+err:
+    if (p) {
+        pbuf_free(p);
+    }
+    return ESP_NETIF_OPTIONAL_RETURN_CODE(ret);
+}
+
+static err_t tun_output(struct netif *netif, struct pbuf *p)
+{
+    LWIP_ASSERT("netif != NULL", (netif != NULL));
+    LWIP_ASSERT("netif->state != NULL", (netif->state != NULL));
+    LWIP_ASSERT("p != NULL", (p != NULL));
+    esp_err_t ret = esp_netif_transmit(netif->state, p->payload, p->len);
+    switch (ret) {
+    case ESP_OK:
+        return ERR_OK;
+    case ESP_ERR_NO_MEM:
+        return ERR_MEM;
+#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(5, 4, 0)
+    case ESP_ERR_ESP_NETIF_TX_FAILED:
+        return ERR_BUF;
+#endif
+    case ESP_ERR_INVALID_ARG:
+        return ERR_ARG;
+    default:
+        return ERR_IF;
+    }
+}
+
+static err_t tun_output_v4(struct netif *netif, struct pbuf *p, const ip4_addr_t *ipaddr)
+{
+    LWIP_UNUSED_ARG(ipaddr);
+    return tun_output(netif, p);
+}
+#if LWIP_IPV6
+static err_t tun_output_v6(struct netif *netif, struct pbuf *p, const ip6_addr_t *ipaddr)
+{
+    LWIP_UNUSED_ARG(ipaddr);
+    return tun_output(netif, p);
+}
+#endif
+static err_t tun_init(struct netif *netif)
+{
+    if (netif == NULL) {
+        return ERR_IF;
+    }
+    netif->name[0] = 't';
+    netif->name[1] = 'u';
+#if LWIP_IPV4
+    netif->output = tun_output_v4;
+#endif
+#if LWIP_IPV6
+    netif->output_ip6 = tun_output_v6;
+#endif
+    netif->mtu = 1500;
+    return ERR_OK;
+}
+
+static const struct esp_netif_netstack_config s_config_tun = {
+    .lwip = {
+        .init_fn = tun_init,
+        .input_fn = tun_input,
+    }
+};
+
+const esp_netif_netstack_config_t *g_eppp_netif_config_tun = &s_config_tun;
+
+static void cmd_ping_on_ping_success(esp_ping_handle_t hdl, void *args)
+{
+    uint8_t ttl;
+    uint16_t seqno;
+    uint32_t elapsed_time, recv_len;
+    ip_addr_t target_addr;
+    esp_ping_get_profile(hdl, ESP_PING_PROF_SEQNO, &seqno, sizeof(seqno));
+    esp_ping_get_profile(hdl, ESP_PING_PROF_TTL, &ttl, sizeof(ttl));
+    esp_ping_get_profile(hdl, ESP_PING_PROF_IPADDR, &target_addr, sizeof(target_addr));
+    esp_ping_get_profile(hdl, ESP_PING_PROF_SIZE, &recv_len, sizeof(recv_len));
+    esp_ping_get_profile(hdl, ESP_PING_PROF_TIMEGAP, &elapsed_time, sizeof(elapsed_time));
+    ESP_LOGD(TAG, "%" PRIu32 " bytes from %s icmp_seq=%" PRIu16 " ttl=%" PRIu16 " time=%" PRIu32 " ms\n",
+             recv_len, ipaddr_ntoa((ip_addr_t *)&target_addr), seqno, ttl, elapsed_time);
+    if (esp_ping_stop(hdl) != ESP_OK) {
+        ESP_LOGE(TAG, "Failed to stop ping session");
+        // continue to delete the session
+    }
+    esp_ping_delete_session(hdl);
+    ESP_LOGI(TAG, "PING success -> stop and post IP");
+    esp_netif_t *netif = (esp_netif_t *)args;
+    esp_netif_ip_info_t ip = {0};
+    esp_netif_get_ip_info(netif, &ip);
+    esp_netif_set_ip_info(netif, &ip);
+}
+
+static void cmd_ping_on_ping_timeout(esp_ping_handle_t hdl, void *args)
+{
+    uint16_t seqno;
+    ip_addr_t target_addr;
+    esp_ping_get_profile(hdl, ESP_PING_PROF_SEQNO, &seqno, sizeof(seqno));
+    esp_ping_get_profile(hdl, ESP_PING_PROF_IPADDR, &target_addr, sizeof(target_addr));
+    ESP_LOGD(TAG, "From %s icmp_seq=%" PRIu16 "timeout", ipaddr_ntoa((ip_addr_t *)&target_addr), seqno);
+}
+
+static void cmd_ping_on_ping_end(esp_ping_handle_t hdl, void *args)
+{
+    ip_addr_t target_addr;
+    uint32_t transmitted;
+    uint32_t received;
+    uint32_t total_time_ms;
+    uint32_t loss;
+
+    esp_ping_get_profile(hdl, ESP_PING_PROF_REQUEST, &transmitted, sizeof(transmitted));
+    esp_ping_get_profile(hdl, ESP_PING_PROF_REPLY, &received, sizeof(received));
+    esp_ping_get_profile(hdl, ESP_PING_PROF_IPADDR, &target_addr, sizeof(target_addr));
+    esp_ping_get_profile(hdl, ESP_PING_PROF_DURATION, &total_time_ms, sizeof(total_time_ms));
+
+    if (transmitted > 0) {
+        loss = (uint32_t)((1 - ((float)received) / transmitted) * 100);
+    } else {
+        loss = 0;
+    }
+    if (IP_IS_V4(&target_addr)) {
+        ESP_LOGD(TAG, "\n--- %s ping statistics ---\n", inet_ntoa(*ip_2_ip4(&target_addr)));
+    }
+#if LWIP_IPV6
+    else {
+        ESP_LOGD(TAG, "\n--- %s ping statistics ---\n", inet6_ntoa(*ip_2_ip6(&target_addr)));
+    }
+#endif
+    ESP_LOGI(TAG, "%" PRIu32 " packets transmitted, %" PRIu32 " received, %" PRIu32 "%% packet loss, time %" PRIu32 "ms\n",
+             transmitted, received, loss, total_time_ms);
+    esp_ping_delete_session(hdl);
+}
+
+esp_err_t eppp_check_connection(esp_netif_t *netif)
+{
+    esp_err_t ret = ESP_OK;
+    esp_ping_config_t config = ESP_PING_DEFAULT_CONFIG();
+#if CONFIG_LOG_MAXIMUM_LEVEL > 3
+    config.task_stack_size += 1024;  // Some additional stack needed for verbose logs
+#endif
+    config.count = 100;
+    ESP_LOGI(TAG, "Checking connection on EPPP interface #%" PRIu32, config.interface);
+    ip_addr_t target_addr = {0};
+    esp_netif_ip_info_t ip;
+    esp_netif_get_ip_info(netif, &ip);
+#if LWIP_IPV6
+    target_addr.u_addr.ip4.addr =  ip.gw.addr;
+#else
+    target_addr.addr =  ip.gw.addr;
+#endif
+    config.target_addr = target_addr;
+    esp_ping_callbacks_t cbs = {
+        .cb_args = netif,
+        .on_ping_success = cmd_ping_on_ping_success,
+        .on_ping_timeout = cmd_ping_on_ping_timeout,
+        .on_ping_end = cmd_ping_on_ping_end
+    };
+    esp_ping_handle_t ping;
+    ESP_GOTO_ON_ERROR(esp_ping_new_session(&config, &cbs, &ping), err, TAG, "Failed to create ping session");
+    ESP_GOTO_ON_ERROR(esp_ping_start(ping), err, TAG, "Failed to start ping session");
+    ESP_LOGI(TAG, "Ping started");
+    return ret;
+err:
+    ESP_LOGE(TAG, "Failed to start connection check");
+    return ret;
+}

components/eppp_link/eppp_sdio.c

@@ -0,0 +1,92 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <string.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include "esp_log.h"
+#include "esp_netif.h"
+#include "esp_check.h"
+#include "esp_mac.h"
+#include "eppp_link.h"
+#include "eppp_transport.h"
+#include "eppp_transport_sdio.h"
+#include "eppp_sdio.h"
+
+#define TAG "eppp_sdio"
+
+struct eppp_sdio {
+    struct eppp_handle parent;
+    bool is_host;
+};
+
+esp_err_t eppp_sdio_host_tx(void *h, void *buffer, size_t len);
+esp_err_t eppp_sdio_host_rx(esp_netif_t *netif);
+esp_err_t eppp_sdio_slave_rx(esp_netif_t *netif);
+esp_err_t eppp_sdio_slave_tx(void *h, void *buffer, size_t len);
+esp_err_t eppp_sdio_host_init(struct eppp_config_sdio_s *config);
+esp_err_t eppp_sdio_slave_init(struct eppp_config_sdio_s *config);
+void eppp_sdio_slave_deinit(void);
+void eppp_sdio_host_deinit(void);
+
+esp_err_t eppp_perform(esp_netif_t *netif)
+{
+    struct eppp_handle *h = esp_netif_get_io_driver(netif);
+    if (h->stop) {
+        return ESP_ERR_TIMEOUT;
+    }
+    struct eppp_sdio *handle = __containerof(h, struct eppp_sdio, parent);;
+    if (handle->is_host) {
+        return eppp_sdio_host_rx(netif);
+    } else {
+        return eppp_sdio_slave_rx(netif);
+    }
+}
+
+static esp_err_t post_attach(esp_netif_t *esp_netif, void *args)
+{
+    eppp_transport_handle_t h = (eppp_transport_handle_t)args;
+    ESP_RETURN_ON_FALSE(h, ESP_ERR_INVALID_ARG, TAG, "Transport handle cannot be null");
+    struct eppp_sdio *sdio = __containerof(h, struct eppp_sdio, parent);
+    h->base.netif = esp_netif;
+
+    esp_netif_driver_ifconfig_t driver_ifconfig = {
+        .handle =  h,
+        .transmit = sdio->is_host ? eppp_sdio_host_tx : eppp_sdio_slave_tx,
+    };
+
+    ESP_RETURN_ON_ERROR(esp_netif_set_driver_config(esp_netif, &driver_ifconfig), TAG, "Failed to set driver config");
+    ESP_LOGI(TAG, "EPPP SDIO transport attached to EPPP netif %s", esp_netif_get_desc(esp_netif));
+    return ESP_OK;
+}
+
+eppp_transport_handle_t eppp_sdio_init(struct eppp_config_sdio_s *config)
+{
+    __attribute__((unused)) esp_err_t ret = ESP_OK;
+    ESP_RETURN_ON_FALSE(config, NULL, TAG, "Config cannot be null");
+    struct eppp_sdio *h = calloc(1, sizeof(struct eppp_sdio));
+    ESP_RETURN_ON_FALSE(h, NULL, TAG, "Failed to allocate eppp_handle");
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+    h->parent.channel_tx = eppp_sdio_transmit_channel;
+#endif
+    h->parent.base.post_attach = post_attach;
+    h->is_host = config->is_host;
+    esp_err_t (*init_fn)(struct eppp_config_sdio_s * eppp_config) = h->is_host ? eppp_sdio_host_init : eppp_sdio_slave_init;
+    ESP_GOTO_ON_ERROR(init_fn(config), err, TAG, "Failed to init SDIO");
+    return &h->parent;
+err:
+    free(h);
+    return NULL;
+}
+
+void eppp_sdio_deinit(eppp_transport_handle_t h)
+{
+    struct eppp_sdio *sdio = __containerof(h, struct eppp_sdio, parent);
+    if (sdio->is_host) {
+        eppp_sdio_host_deinit();
+    } else {
+        eppp_sdio_slave_deinit();
+    }
+}

components/eppp_link/eppp_sdio.h

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -8,8 +8,10 @@
 #define MAX_SDIO_PAYLOAD 1500
 #define SDIO_ALIGN(size) (((size) + 3U) & ~(3U))
 #define SDIO_PAYLOAD SDIO_ALIGN(MAX_SDIO_PAYLOAD)
+#define SDIO_PACKET_SIZE SDIO_ALIGN(MAX_SDIO_PAYLOAD + 4)
 #define PPP_SOF 0x7E
 
+
 // Interrupts and registers
 #define SLAVE_INTR      0
 #define SLAVE_REG_REQ   0
@@ -17,3 +19,11 @@
 // Requests from host to slave
 #define REQ_RESET 1
 #define REQ_INIT  2
+
+struct header {
+    uint8_t magic;
+    uint8_t channel;
+    uint16_t size;
+} __attribute__((packed));
+
+esp_err_t eppp_sdio_transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len);

components/eppp_link/eppp_sdio_host.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -15,6 +15,7 @@
 #include "sdmmc_cmd.h"
 #include "esp_check.h"
 #include "eppp_link.h"
+#include "eppp_transport.h"
 
 #if CONFIG_EPPP_LINK_DEVICE_SDIO_HOST
 
@@ -28,22 +29,23 @@ static SemaphoreHandle_t s_essl_mutex = NULL;
 static essl_handle_t s_essl = NULL;
 static sdmmc_card_t *s_card = NULL;
 
-static DRAM_DMA_ALIGNED_ATTR uint8_t send_buffer[SDIO_PAYLOAD];
-static DMA_ATTR uint8_t rcv_buffer[SDIO_PAYLOAD];
+static DRAM_DMA_ALIGNED_ATTR uint8_t send_buffer[SDIO_PACKET_SIZE];
+static DMA_ATTR uint8_t rcv_buffer[SDIO_PACKET_SIZE];
 
-esp_err_t eppp_sdio_host_tx(void *h, void *buffer, size_t len)
+static esp_err_t eppp_sdio_host_tx_generic(int channel, void *buffer, size_t len)
 {
     if (s_essl == NULL || s_essl_mutex == NULL) {
         // silently skip the Tx if the SDIO not fully initialized
         return ESP_OK;
     }
 
-    memcpy(send_buffer, buffer, len);
-    size_t send_len = SDIO_ALIGN(len);
-    if (send_len > len) {
-        // pad with SOF's
-        memset(&send_buffer[len], PPP_SOF, send_len - len);
-    }
+
+    struct header *head = (void *)send_buffer;
+    head->magic = PPP_SOF;
+    head->channel = channel;
+    head->size = len;
+    memcpy(send_buffer + sizeof(struct header), buffer, len);
+    size_t send_len = SDIO_ALIGN(len + sizeof(struct header));
     xSemaphoreTake(s_essl_mutex, portMAX_DELAY);
     esp_err_t ret = essl_send_packet(s_essl, send_buffer, send_len, PACKET_TIMEOUT_MS);
     if (ret != ESP_OK) {
@@ -56,6 +58,19 @@ esp_err_t eppp_sdio_host_tx(void *h, void *buffer, size_t len)
     return ret;
 }
 
+esp_err_t eppp_sdio_host_tx(void *h, void *buffer, size_t len)
+{
+    return eppp_sdio_host_tx_generic(0, buffer, len);
+}
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+esp_err_t eppp_sdio_transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    return eppp_sdio_host_tx_generic(channel, buffer, len);
+}
+#endif
+
+
 static esp_err_t request_slave_reset(void)
 {
     esp_err_t ret = ESP_OK;
@@ -145,15 +160,37 @@ esp_err_t eppp_sdio_host_rx(esp_netif_t *netif)
     if (intr & ESSL_SDIO_DEF_ESP32.new_packet_intr_mask) {
         esp_err_t ret;
         do {
-            size_t size_read = SDIO_PAYLOAD;
-            ret = essl_get_packet(s_essl, rcv_buffer, SDIO_PAYLOAD, &size_read, PACKET_TIMEOUT_MS);
+            size_t size_read = SDIO_PACKET_SIZE;
+            ret = essl_get_packet(s_essl, rcv_buffer, SDIO_PACKET_SIZE, &size_read, PACKET_TIMEOUT_MS);
             if (ret == ESP_ERR_NOT_FOUND) {
                 ESP_LOGE(TAG, "interrupt but no data can be read");
                 break;
             } else if (ret == ESP_OK) {
                 ESP_LOGD(TAG, "receive data, size: %d", size_read);
+                struct header *head = (void *)rcv_buffer;
+                if (head->magic != PPP_SOF) {
+                    ESP_LOGE(TAG, "invalid magic %x", head->magic);
+                    break;
+                }
+                if (head->channel > NR_OF_CHANNELS) {
+                    ESP_LOGE(TAG, "invalid channel %x", head->channel);
+                    break;
+                }
+                if (head->size > SDIO_PAYLOAD || head->size > size_read) {
+                    ESP_LOGE(TAG, "invalid size %x", head->size);
+                    break;
+                }
                 ESP_LOG_BUFFER_HEXDUMP(TAG, rcv_buffer, size_read, ESP_LOG_VERBOSE);
-                esp_netif_receive(netif, rcv_buffer, size_read, NULL);
+                if (head->channel == 0) {
+                    esp_netif_receive(netif, rcv_buffer + sizeof(struct header), head->size, NULL);
+                } else {
+#if defined(CONFIG_EPPP_LINK_CHANNELS_SUPPORT)
+                    struct eppp_handle *h = esp_netif_get_io_driver(netif);
+                    if (h->channel_rx) {
+                        h->channel_rx(netif, head->channel, rcv_buffer + sizeof(struct header), head->size);
+                    }
+#endif
+                }
                 break;
             } else {
                 ESP_LOGE(TAG, "rx packet error: %08X", ret);

components/eppp_link/eppp_sdio_slave.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -9,9 +9,10 @@
 #include "esp_log.h"
 #include "esp_netif.h"
 #include "driver/sdio_slave.h"
+#include "eppp_link.h"
+#include "eppp_transport.h"
 #include "eppp_sdio.h"
 #include "esp_check.h"
-
 #if CONFIG_EPPP_LINK_DEVICE_SDIO_SLAVE
 #define BUFFER_NUM 4
 #define BUFFER_SIZE SDIO_PAYLOAD
@@ -20,19 +21,18 @@ static DMA_ATTR uint8_t sdio_slave_rx_buffer[BUFFER_NUM][BUFFER_SIZE];
 static DMA_ATTR uint8_t sdio_slave_tx_buffer[SDIO_PAYLOAD];
 static int s_slave_request = 0;
 
-esp_err_t eppp_sdio_slave_tx(void *h, void *buffer, size_t len)
+static esp_err_t eppp_sdio_host_tx_generic(int channel, void *buffer, size_t len)
 {
     if (s_slave_request != REQ_INIT) {
         // silently skip the Tx if the SDIO not fully initialized
         return ESP_OK;
     }
-    memcpy(sdio_slave_tx_buffer, buffer, len);
-    size_t send_len = SDIO_ALIGN(len);
-    if (send_len > len) {
-        // pad with SOF's if the size is not 4 bytes aligned
-        memset(&sdio_slave_tx_buffer[len], PPP_SOF, send_len - len);
-    }
-
+    struct header *head = (void *)sdio_slave_tx_buffer;
+    head->magic = PPP_SOF;
+    head->channel = channel;
+    head->size = len;
+    memcpy(sdio_slave_tx_buffer + sizeof(struct header), buffer, len);
+    size_t send_len = SDIO_ALIGN(len + sizeof(struct header));
     ESP_LOG_BUFFER_HEXDUMP(TAG, sdio_slave_tx_buffer, send_len, ESP_LOG_VERBOSE);
     esp_err_t ret = sdio_slave_transmit(sdio_slave_tx_buffer, send_len);
     if (ret != ESP_OK) {
@@ -43,6 +43,18 @@ esp_err_t eppp_sdio_slave_tx(void *h, void *buffer, size_t len)
     return ESP_OK;
 }
 
+esp_err_t eppp_sdio_slave_tx(void *h, void *buffer, size_t len)
+{
+    return eppp_sdio_host_tx_generic(0, buffer, len);
+}
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+esp_err_t eppp_sdio_transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    return eppp_sdio_host_tx_generic(channel, buffer, len);
+}
+#endif
+
 static esp_err_t slave_reset(void)
 {
     esp_err_t ret = ESP_OK;
@@ -81,7 +93,29 @@ esp_err_t eppp_sdio_slave_rx(esp_netif_t *netif)
     if (ret == ESP_ERR_NOT_FINISHED || ret == ESP_OK) {
 again:
         ptr = sdio_slave_recv_get_buf(handle, &length);
-        esp_netif_receive(netif, ptr, length, NULL);
+        struct header *head = (void *)ptr;
+        if (head->magic != PPP_SOF) {
+            ESP_LOGE(TAG, "invalid magic %x", head->magic);
+            return ESP_FAIL;
+        }
+        if (head->channel > NR_OF_CHANNELS) {
+            ESP_LOGE(TAG, "invalid channel %x", head->channel);
+            return ESP_FAIL;
+        }
+        if (head->size > SDIO_PAYLOAD || head->size > length) {
+            ESP_LOGE(TAG, "invalid size %x", head->size);
+            return ESP_FAIL;
+        }
+        if (head->channel == 0) {
+            esp_netif_receive(netif, ptr + sizeof(struct header), head->size, NULL);
+        } else {
+#if defined(CONFIG_EPPP_LINK_CHANNELS_SUPPORT)
+            struct eppp_handle *h = esp_netif_get_io_driver(netif);
+            if (h->channel_rx) {
+                h->channel_rx(netif, head->channel, ptr + sizeof(struct header), head->size);
+            }
+#endif
+        }
         if (sdio_slave_recv_load_buf(handle) != ESP_OK) {
             ESP_LOGE(TAG, "Failed to recycle packet buffer");
             return ESP_FAIL;
@@ -109,7 +143,7 @@ static void event_cb(uint8_t pos)
     }
 }
 
-esp_err_t eppp_sdio_slave_init(void)
+esp_err_t eppp_sdio_slave_init(struct eppp_config_sdio_s *eppp_config)
 {
     sdio_slave_config_t config = {
         .sending_mode       = SDIO_SLAVE_SEND_PACKET,
@@ -166,7 +200,7 @@ void eppp_sdio_slave_deinit(void)
 {
 }
 
-esp_err_t eppp_sdio_slave_init(void)
+esp_err_t eppp_sdio_slave_init(struct eppp_config_sdio_s *config)
 {
     return ESP_ERR_NOT_SUPPORTED;
 }

components/eppp_link/eppp_spi.c

@@ -0,0 +1,495 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <string.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include "sdkconfig.h"
+#include "esp_log.h"
+#include "esp_netif.h"
+#include "esp_check.h"
+#include "esp_event.h"
+#include "esp_mac.h"
+#include "eppp_link.h"
+#include "eppp_transport.h"
+#include "eppp_transport_spi.h"
+#include "driver/spi_master.h"
+#include "driver/spi_slave.h"
+#include "driver/gpio.h"
+#include "esp_timer.h"
+#include "esp_rom_crc.h"
+
+#define TAG "eppp_spi"
+
+#define MAX_PAYLOAD 1500
+#define MIN_TRIGGER_US 20
+#define PPP_SOF 0x7E
+#define SPI_HEADER_MAGIC PPP_SOF
+#define SPI_ALIGN(size) (((size) + 3U) & ~(3U))
+#define TRANSFER_SIZE SPI_ALIGN((MAX_PAYLOAD + 6))
+#define NEXT_TRANSACTION_SIZE(a,b) (((a)>(b))?(a):(b)) /* next transaction: whichever is bigger */
+
+struct packet {
+    size_t len;
+    uint8_t *data;
+    int channel;
+};
+
+struct header {
+    uint8_t magic;
+    uint8_t channel;
+    uint16_t size;
+    uint16_t next_size;
+    uint16_t check;
+} __attribute__((packed));
+
+enum blocked_status {
+    NONE,
+    MASTER_BLOCKED,
+    MASTER_WANTS_READ,
+    SLAVE_BLOCKED,
+    SLAVE_WANTS_WRITE,
+};
+
+struct eppp_spi {
+    struct eppp_handle parent;
+    bool is_master;
+    QueueHandle_t out_queue;
+    QueueHandle_t ready_semaphore;
+    spi_device_handle_t spi_device;
+    spi_host_device_t spi_host;
+    int gpio_intr;
+    uint16_t next_size;
+    uint16_t transaction_size;
+    struct packet outbound;
+    enum blocked_status blocked;
+    uint32_t slave_last_edge;
+    esp_timer_handle_t timer;
+};
+
+static esp_err_t transmit_generic(struct eppp_spi *handle, int channel, void *buffer, size_t len)
+{
+
+    struct packet buf = { .channel = channel };
+    uint8_t *current_buffer = buffer;
+    size_t remaining = len;
+    do {    // TODO(IDF-9194): Refactor this loop to allocate only once and perform
+        //       fragmentation after receiving from the queue (applicable only if MTU > MAX_PAYLOAD)
+        size_t batch = remaining > MAX_PAYLOAD ? MAX_PAYLOAD : remaining;
+        buf.data = malloc(batch);
+        if (buf.data == NULL) {
+            ESP_LOGE(TAG, "Failed to allocate packet");
+            return ESP_ERR_NO_MEM;
+        }
+        buf.len = batch;
+        remaining -= batch;
+        memcpy(buf.data, current_buffer, batch);
+        current_buffer += batch;
+        BaseType_t ret = xQueueSend(handle->out_queue, &buf, 0);
+        if (ret != pdTRUE) {
+            ESP_LOGE(TAG, "Failed to queue packet to slave!");
+            return ESP_ERR_NO_MEM;
+        }
+    } while (remaining > 0);
+
+    if (!handle->is_master && handle->blocked == SLAVE_BLOCKED) {
+        uint32_t now = esp_timer_get_time();
+        uint32_t diff = now - handle->slave_last_edge;
+        if (diff < MIN_TRIGGER_US) {
+            esp_rom_delay_us(MIN_TRIGGER_US - diff);
+        }
+        gpio_set_level(handle->gpio_intr, 0);
+    }
+    return ESP_OK;
+}
+
+static esp_err_t transmit(void *h, void *buffer, size_t len)
+{
+    struct eppp_handle *handle = h;
+    struct eppp_spi *spi_handle = __containerof(handle, struct eppp_spi, parent);;
+    return transmit_generic(spi_handle, 0, buffer, len);
+}
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+static esp_err_t transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    struct eppp_handle *handle = esp_netif_get_io_driver(netif);
+    struct eppp_spi *spi_handle = __containerof(handle, struct eppp_spi, parent);;
+    return transmit_generic(spi_handle, channel, buffer, len);
+}
+#endif
+
+static void IRAM_ATTR timer_callback(void *arg)
+{
+    struct eppp_spi *h = arg;
+    if (h->blocked == SLAVE_WANTS_WRITE) {
+        gpio_set_level(h->gpio_intr, 0);
+    }
+}
+
+static void IRAM_ATTR gpio_isr_handler(void *arg)
+{
+    static uint32_t s_last_time;
+    uint32_t now = esp_timer_get_time();
+    uint32_t diff = now - s_last_time;
+    if (diff < MIN_TRIGGER_US) { // debounce
+        return;
+    }
+    s_last_time = now;
+    struct eppp_spi *h = arg;
+    BaseType_t yield = false;
+
+    // Positive edge means SPI slave prepared the data
+    if (gpio_get_level(h->gpio_intr) == 1) {
+        xSemaphoreGiveFromISR(h->ready_semaphore, &yield);
+        if (yield) {
+            portYIELD_FROM_ISR();
+        }
+        return;
+    }
+
+    // Negative edge (when master blocked) means that slave wants to transmit
+    if (h->blocked == MASTER_BLOCKED) {
+        struct packet buf = { .data = NULL, .len = -1 };
+        xQueueSendFromISR(h->out_queue, &buf, &yield);
+        if (yield) {
+            portYIELD_FROM_ISR();
+        }
+    }
+}
+
+static esp_err_t deinit_master(struct eppp_spi *h)
+{
+    ESP_RETURN_ON_ERROR(spi_bus_remove_device(h->spi_device), TAG, "Failed to remove SPI bus");
+    ESP_RETURN_ON_ERROR(spi_bus_free(h->spi_host), TAG, "Failed to free SPI bus");
+    return ESP_OK;
+}
+
+static esp_err_t init_master(struct eppp_config_spi_s *config, struct eppp_spi *h)
+{
+    esp_err_t ret = ESP_OK;
+    h->spi_host = config->host;
+    h->gpio_intr = config->intr;
+    spi_bus_config_t bus_cfg = {};
+    bus_cfg.mosi_io_num = config->mosi;
+    bus_cfg.miso_io_num = config->miso;
+    bus_cfg.sclk_io_num = config->sclk;
+    bus_cfg.quadwp_io_num = -1;
+    bus_cfg.quadhd_io_num = -1;
+    bus_cfg.max_transfer_sz = TRANSFER_SIZE;
+    bus_cfg.flags = 0;
+    bus_cfg.intr_flags = 0;
+
+    // TODO(IDF-13351): Init and deinit SPI bus separately (per Kconfig?)
+    ESP_RETURN_ON_ERROR(spi_bus_initialize(config->host, &bus_cfg, SPI_DMA_CH_AUTO), TAG, "Failed to init SPI bus");
+
+    spi_device_interface_config_t dev_cfg = {};
+    dev_cfg.clock_speed_hz = config->freq;
+    dev_cfg.mode = 0;
+    dev_cfg.spics_io_num = config->cs;
+    dev_cfg.cs_ena_pretrans = config->cs_ena_pretrans;
+    dev_cfg.cs_ena_posttrans = config->cs_ena_posttrans;
+    dev_cfg.duty_cycle_pos = 128;
+    dev_cfg.input_delay_ns = config->input_delay_ns;
+    dev_cfg.pre_cb = NULL;
+    dev_cfg.post_cb = NULL;
+    dev_cfg.queue_size = 3;
+
+    ESP_GOTO_ON_ERROR(spi_bus_add_device(config->host, &dev_cfg, &h->spi_device), err, TAG, "Failed to add SPI device");
+
+    //GPIO config for the handshake line.
+    gpio_config_t io_conf = {
+        .intr_type = GPIO_INTR_ANYEDGE,
+        .mode = GPIO_MODE_INPUT,
+        .pull_up_en = 1,
+        .pin_bit_mask = BIT64(config->intr),
+    };
+
+    ESP_GOTO_ON_ERROR(gpio_config(&io_conf), err_dev, TAG, "Failed to config interrupt GPIO");
+    ret = gpio_install_isr_service(0);
+    ESP_GOTO_ON_FALSE(ret == ESP_OK || ret == ESP_ERR_INVALID_STATE /* In case the GPIO ISR already installed */,
+                      ret, err_dev, TAG, "Failed to install GPIO ISR");
+    ESP_GOTO_ON_ERROR(gpio_set_intr_type(config->intr, GPIO_INTR_ANYEDGE), err_dev, TAG, "Failed to set ISR type");
+    ESP_GOTO_ON_ERROR(gpio_isr_handler_add(config->intr, gpio_isr_handler, h), err_dev, TAG, "Failed to add ISR handler");
+    return ESP_OK;
+err_dev:
+    spi_bus_remove_device(h->spi_device);
+err:
+    spi_bus_free(config->host);
+    return ret;
+}
+
+static void post_setup(spi_slave_transaction_t *trans)
+{
+    struct eppp_spi *h = trans->user;
+    h->slave_last_edge = esp_timer_get_time();
+    gpio_set_level(h->gpio_intr, 1);
+    if (h->transaction_size == 0) { // If no transaction planned:
+        if (h->outbound.len == 0) { // we're blocked if we don't have any data
+            h->blocked = SLAVE_BLOCKED;
+        } else {
+            h->blocked = SLAVE_WANTS_WRITE; // we notify the master that we want to write
+            esp_timer_start_once(h->timer, MIN_TRIGGER_US);
+        }
+    }
+}
+
+static void post_transaction(spi_slave_transaction_t *transaction)
+{
+    struct eppp_spi *h = transaction->user;
+    h->blocked = NONE;
+    gpio_set_level(h->gpio_intr, 0);
+}
+
+static esp_err_t deinit_slave(struct eppp_spi *h)
+{
+    ESP_RETURN_ON_ERROR(spi_slave_free(h->spi_host), TAG, "Failed to free SPI slave host");
+    ESP_RETURN_ON_ERROR(spi_bus_remove_device(h->spi_device), TAG, "Failed to remove SPI device");
+    ESP_RETURN_ON_ERROR(spi_bus_free(h->spi_host), TAG, "Failed to free SPI bus");
+    return ESP_OK;
+}
+
+static esp_err_t init_slave(struct eppp_config_spi_s *config, struct eppp_spi *h)
+{
+    h->spi_host = config->host;
+    h->gpio_intr = config->intr;
+    spi_bus_config_t bus_cfg = {};
+    bus_cfg.mosi_io_num = config->mosi;
+    bus_cfg.miso_io_num = config->miso;
+    bus_cfg.sclk_io_num = config->sclk;
+    bus_cfg.quadwp_io_num = -1;
+    bus_cfg.quadhd_io_num = -1;
+    bus_cfg.flags = 0;
+    bus_cfg.intr_flags = 0;
+
+    //Configuration for the SPI slave interface
+    spi_slave_interface_config_t slvcfg = {
+        .mode = 0,
+        .spics_io_num = config->cs,
+        .queue_size = 3,
+        .flags = 0,
+        .post_setup_cb = post_setup,
+        .post_trans_cb = post_transaction,
+    };
+
+    //Configuration for the handshake line
+    gpio_config_t io_conf = {
+        .intr_type = GPIO_INTR_DISABLE,
+        .mode = GPIO_MODE_OUTPUT,
+        .pin_bit_mask = BIT64(config->intr),
+    };
+
+    gpio_config(&io_conf);
+    gpio_set_pull_mode(config->mosi, GPIO_PULLUP_ONLY);
+    gpio_set_pull_mode(config->sclk, GPIO_PULLUP_ONLY);
+    gpio_set_pull_mode(config->cs, GPIO_PULLUP_ONLY);
+
+    //Initialize SPI slave interface
+    if (spi_slave_initialize(config->host, &bus_cfg, &slvcfg, SPI_DMA_CH_AUTO) != ESP_OK) {
+        return ESP_FAIL;
+    }
+    return ESP_OK;
+}
+
+typedef esp_err_t (*perform_transaction_t)(struct eppp_spi *h, size_t len, const void *tx_buffer, void *rx_buffer);
+
+static esp_err_t perform_transaction_master(struct eppp_spi *h, size_t len, const void *tx_buffer, void *rx_buffer)
+{
+    spi_transaction_t t = {};
+    t.length = len * 8;
+    t.tx_buffer = tx_buffer;
+    t.rx_buffer = rx_buffer;
+    return spi_device_transmit(h->spi_device, &t);
+}
+
+static esp_err_t perform_transaction_slave(struct eppp_spi *h, size_t len, const void *tx_buffer, void *rx_buffer)
+{
+    spi_slave_transaction_t t = {};
+    t.user = h;
+    t.length = len * 8;
+    t.tx_buffer = tx_buffer;
+    t.rx_buffer = rx_buffer;
+    return spi_slave_transmit(h->spi_host, &t, portMAX_DELAY);
+}
+
+esp_err_t eppp_perform(esp_netif_t *netif)
+{
+    static WORD_ALIGNED_ATTR uint8_t out_buf[TRANSFER_SIZE] = {};
+    static WORD_ALIGNED_ATTR uint8_t in_buf[TRANSFER_SIZE] = {};
+
+    struct eppp_handle *handle = esp_netif_get_io_driver(netif);
+    struct eppp_spi *h = __containerof(handle, struct eppp_spi, parent);
+
+    // Perform transaction for master and slave
+    const perform_transaction_t perform_transaction = h->is_master ? perform_transaction_master : perform_transaction_slave;
+
+    if (h->parent.stop) {
+        return ESP_ERR_TIMEOUT;
+    }
+
+    BaseType_t tx_queue_stat;
+    bool allow_test_tx = false;
+    uint16_t next_tx_size = 0;
+    if (h->is_master) {
+        // SPI MASTER only code
+        if (xSemaphoreTake(h->ready_semaphore, pdMS_TO_TICKS(1000)) != pdTRUE) {
+            // slave might not be ready, but maybe we just missed an interrupt
+            allow_test_tx = true;
+        }
+        if (h->outbound.len == 0 && h->transaction_size == 0 && h->blocked == NONE) {
+            h->blocked = MASTER_BLOCKED;
+            xQueueReceive(h->out_queue, &h->outbound, portMAX_DELAY);
+            h->blocked = NONE;
+            if (h->outbound.len == -1) {
+                h->outbound.len = 0;
+                h->blocked = MASTER_WANTS_READ;
+            }
+        } else if (h->blocked == MASTER_WANTS_READ) {
+            h->blocked = NONE;
+        }
+    }
+    struct header *head = (void *)out_buf;
+    if (h->outbound.len <= h->transaction_size && allow_test_tx == false) {
+        // sending outbound
+        head->size = h->outbound.len;
+        head->channel = h->outbound.channel;
+        if (h->outbound.len > 0) {
+            memcpy(out_buf + sizeof(struct header), h->outbound.data, h->outbound.len);
+            free(h->outbound.data);
+            ESP_LOG_BUFFER_HEXDUMP(TAG, out_buf + sizeof(struct header), head->size, ESP_LOG_VERBOSE);
+            h->outbound.data = NULL;
+            h->outbound.len = 0;
+        }
+        do {
+            tx_queue_stat = xQueueReceive(h->out_queue, &h->outbound, 0);
+        } while (tx_queue_stat == pdTRUE && h->outbound.len == -1);
+        if (h->outbound.len == -1) { // used as a signal only, no actual data
+            h->outbound.len = 0;
+        }
+    } else {
+        // outbound is bigger, need to transmit in another transaction (keep this empty)
+        head->size = 0;
+        head->channel = 0;
+    }
+    next_tx_size = head->next_size = h->outbound.len;
+    head->magic = SPI_HEADER_MAGIC;
+    head->check = esp_rom_crc16_le(0, out_buf, sizeof(struct header) - sizeof(uint16_t));
+    esp_err_t ret = perform_transaction(h, sizeof(struct header) + h->transaction_size, out_buf, in_buf);
+    if (ret != ESP_OK) {
+        ESP_LOGE(TAG, "spi_device_transmit failed");
+        h->transaction_size = 0; // need to start with HEADER only transaction
+        return ESP_FAIL;
+    }
+    head = (void *)in_buf;
+    uint16_t check = esp_rom_crc16_le(0, in_buf, sizeof(struct header) - sizeof(uint16_t));
+    if (check != head->check || head->magic != SPI_HEADER_MAGIC || head->channel > NR_OF_CHANNELS) {
+        h->transaction_size = 0; // need to start with HEADER only transaction
+        if (allow_test_tx) {
+            return ESP_OK;
+        }
+        ESP_LOGE(TAG, "Wrong checksum, magic, or channel: %x %x %x", check, head->magic, head->channel);
+        return ESP_FAIL;
+    }
+    if (head->size > 0) {
+        ESP_LOG_BUFFER_HEXDUMP(TAG, in_buf + sizeof(struct header), head->size, ESP_LOG_VERBOSE);
+        if (head->channel == 0) {
+            esp_netif_receive(netif, in_buf + sizeof(struct header), head->size, NULL);
+        } else {
+#if defined(CONFIG_EPPP_LINK_CHANNELS_SUPPORT)
+            if (h->parent.channel_rx) {
+                h->parent.channel_rx(netif, head->channel, in_buf + sizeof(struct header), head->size);
+            }
+#endif
+        }
+    }
+    h->transaction_size = NEXT_TRANSACTION_SIZE(next_tx_size, head->next_size);
+    return ESP_OK;
+}
+
+
+static esp_err_t init_driver(struct eppp_spi *h, struct eppp_config_spi_s *config)
+{
+    if (config->is_master) {
+        return init_master(config, h);
+    }
+    return init_slave(config, h);
+}
+
+static esp_err_t post_attach(esp_netif_t *esp_netif, void *args)
+{
+    eppp_transport_handle_t h = (eppp_transport_handle_t)args;
+    ESP_RETURN_ON_FALSE(h, ESP_ERR_INVALID_ARG, TAG, "Transport handle cannot be null");
+    h->base.netif = esp_netif;
+
+    esp_netif_driver_ifconfig_t driver_ifconfig = {
+        .handle =  h,
+        .transmit = transmit,
+    };
+
+    ESP_RETURN_ON_ERROR(esp_netif_set_driver_config(esp_netif, &driver_ifconfig), TAG, "Failed to set driver config");
+    ESP_LOGI(TAG, "EPPP SPI transport attached to EPPP netif %s", esp_netif_get_desc(esp_netif));
+    return ESP_OK;
+}
+
+
+eppp_transport_handle_t eppp_spi_init(struct eppp_config_spi_s *config)
+{
+    __attribute__((unused)) esp_err_t ret = ESP_OK;
+    ESP_RETURN_ON_FALSE(config, NULL, TAG, "Config cannot be null");
+    struct eppp_spi *h = calloc(1, sizeof(struct eppp_spi));
+    ESP_RETURN_ON_FALSE(h, NULL, TAG, "Failed to allocate eppp_handle");
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+    h->parent.channel_tx = transmit_channel;
+#endif
+    h->is_master = config->is_master;
+    h->parent.base.post_attach = post_attach;
+    h->out_queue = xQueueCreate(CONFIG_EPPP_LINK_PACKET_QUEUE_SIZE, sizeof(struct packet));
+    ESP_GOTO_ON_FALSE(h->out_queue, ESP_FAIL, err, TAG, "Failed to create the packet queue");
+    if (h->is_master) {
+        ESP_GOTO_ON_FALSE(h->ready_semaphore = xSemaphoreCreateBinary(), ESP_FAIL, err, TAG, "Failed to create the semaphore");
+    }
+    h->transaction_size = 0;
+    h->outbound.data = NULL;
+    h->outbound.len = 0;
+    if (!h->is_master) {
+        esp_timer_create_args_t args = {
+            .callback = &timer_callback,
+            .arg = h,
+            .name = "spi_slave_tmr"
+        };
+        ESP_GOTO_ON_ERROR(esp_timer_create(&args, &h->timer), err, TAG, "Failed to create timer");
+    }
+    ESP_GOTO_ON_ERROR(init_driver(h, config), err, TAG, "Failed to init SPI driver");
+    return &h->parent;
+err:
+    if (h->out_queue) {
+        vQueueDelete(h->out_queue);
+    }
+    if (h->ready_semaphore) {
+        vSemaphoreDelete(h->ready_semaphore);
+    }
+    free(h);
+    return NULL;
+}
+void eppp_spi_deinit(eppp_transport_handle_t handle)
+{
+    struct eppp_spi *h = __containerof(handle, struct eppp_spi, parent);;
+    if (h->is_master) {
+        deinit_master(h);
+    } else {
+        deinit_slave(h);
+    }
+    struct packet buf = { };
+    while (xQueueReceive(h->out_queue, &buf, 0) == pdTRUE) {
+        if (buf.len > 0) {
+            free(buf.data);
+        }
+    }
+    vQueueDelete(h->out_queue);
+    if (h->is_master) {
+        vSemaphoreDelete(h->ready_semaphore);
+    }
+    free(h);
+}

components/eppp_link/eppp_transport.h

@@ -0,0 +1,29 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#pragma once
+#include "esp_netif_types.h"
+#include "sdkconfig.h"
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+#define NR_OF_CHANNELS CONFIG_EPPP_LINK_NR_OF_CHANNELS
+#else
+#define NR_OF_CHANNELS 1
+#endif
+
+struct eppp_handle {
+    esp_netif_driver_base_t base;
+    eppp_type_t role;
+    bool stop;
+    bool exited;
+    bool netif_stop;
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+    eppp_channel_fn_t channel_tx;
+    eppp_channel_fn_t channel_rx;
+    void* context;
+#endif
+};
+
+esp_err_t eppp_check_connection(esp_netif_t *netif);

components/eppp_link/eppp_uart.c

@@ -0,0 +1,283 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <string.h>
+#include <stdint.h>
+#include "sdkconfig.h"
+#include "esp_log.h"
+#include "esp_netif.h"
+#include "esp_check.h"
+#include "esp_event.h"
+#include "eppp_link.h"
+#include "eppp_transport.h"
+#include "driver/uart.h"
+
+#define TAG "eppp_uart"
+
+struct eppp_uart {
+    struct eppp_handle parent;
+    QueueHandle_t uart_event_queue;
+    uart_port_t uart_port;
+};
+
+#define MAX_PAYLOAD (1500)
+#define HEADER_MAGIC (0x7E)
+#define HEADER_SIZE (4)
+#define MAX_PACKET_SIZE (MAX_PAYLOAD + HEADER_SIZE)
+/* Maximum size of a packet sent over UART, including header and payload */
+#define UART_BUF_SIZE   (MAX_PACKET_SIZE)
+
+struct header {
+    uint8_t magic;
+    uint8_t channel;
+    uint8_t check;
+    uint16_t size;
+} __attribute__((packed));
+
+static esp_err_t transmit_generic(struct eppp_uart *handle, int channel, void *buffer, size_t len)
+{
+#ifndef CONFIG_EPPP_LINK_USES_PPP
+    static uint8_t out_buf[MAX_PACKET_SIZE] = {};
+    struct header *head = (void *)out_buf;
+    head->magic = HEADER_MAGIC;
+    head->check = 0;
+    head->channel = channel;
+    head->size = len;
+    head->check = (0xFF & len) ^ (len >> 8);
+    memcpy(out_buf + sizeof(struct header), buffer, len);
+    ESP_LOG_BUFFER_HEXDUMP("ppp_uart_send", out_buf, len + sizeof(struct header), ESP_LOG_DEBUG);
+    uart_write_bytes(handle->uart_port, out_buf, len + sizeof(struct header));
+#else
+    ESP_LOG_BUFFER_HEXDUMP("ppp_uart_send", buffer, len, ESP_LOG_DEBUG);
+    uart_write_bytes(handle->uart_port, buffer, len);
+#endif
+    return ESP_OK;
+}
+
+static esp_err_t transmit(void *h, void *buffer, size_t len)
+{
+    struct eppp_handle *handle = h;
+    struct eppp_uart *uart_handle = __containerof(handle, struct eppp_uart, parent);
+    return transmit_generic(uart_handle, 0, buffer, len);
+}
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+static esp_err_t transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    struct eppp_handle *handle = esp_netif_get_io_driver(netif);
+    struct eppp_uart *uart_handle = __containerof(handle, struct eppp_uart, parent);
+    return transmit_generic(uart_handle, channel, buffer, len);
+}
+#endif
+
+static esp_err_t init_uart(struct eppp_uart *h, struct eppp_config_uart_s *config)
+{
+    h->uart_port = config->port;
+    uart_config_t uart_config = {};
+    uart_config.baud_rate = config->baud;
+    uart_config.data_bits = UART_DATA_8_BITS;
+    uart_config.parity    = UART_PARITY_DISABLE;
+    uart_config.stop_bits = UART_STOP_BITS_1;
+    uart_config.flow_ctrl = config->flow_control;
+    uart_config.source_clk = UART_SCLK_DEFAULT;
+
+    ESP_RETURN_ON_ERROR(uart_driver_install(h->uart_port, config->rx_buffer_size, 0, config->queue_size, &h->uart_event_queue, 0), TAG, "Failed to install UART");
+    ESP_RETURN_ON_ERROR(uart_param_config(h->uart_port, &uart_config), TAG, "Failed to set params");
+    ESP_RETURN_ON_ERROR(uart_set_pin(h->uart_port, config->tx_io, config->rx_io, config->rts_io, config->cts_io), TAG, "Failed to set UART pins");
+    ESP_RETURN_ON_ERROR(uart_set_rx_timeout(h->uart_port, 1), TAG, "Failed to set UART Rx timeout");
+    return ESP_OK;
+}
+
+static void deinit_uart(struct eppp_uart *h)
+{
+    uart_driver_delete(h->uart_port);
+}
+
+#ifndef CONFIG_EPPP_LINK_USES_PPP
+/**
+ * @brief Process incoming UART data and extract packets
+ */
+static void process_packet(esp_netif_t *netif, uart_port_t uart_port, size_t available_data)
+{
+    static uint8_t in_buf[2 * UART_BUF_SIZE] = {};
+    static size_t buf_start = 0;
+    static size_t buf_end = 0;
+    struct header *head;
+
+    // Read data directly into our buffer
+    size_t available_space = sizeof(in_buf) - buf_end;
+    size_t read_size = (available_data < available_space) ? available_data : available_space;
+    if (read_size > 0) {
+        size_t len = uart_read_bytes(uart_port, in_buf + buf_end, read_size, 0);
+        ESP_LOG_BUFFER_HEXDUMP("ppp_uart_recv", in_buf + buf_end, len, ESP_LOG_DEBUG);
+
+        if (buf_end + len <= sizeof(in_buf)) {
+            buf_end += len;
+        } else {
+            ESP_LOGW(TAG, "Buffer overflow, discarding data");
+            buf_start = buf_end = 0;
+            return;
+        }
+    }
+
+    // Process while we have enough data for at least a header
+    while ((buf_end - buf_start) >= sizeof(struct header)) {
+        head = (void *)(in_buf + buf_start);
+
+        if (head->magic != HEADER_MAGIC) {
+            goto recover;
+        }
+
+        uint8_t calculated_check = (head->size & 0xFF) ^ (head->size >> 8);
+        if (head->check != calculated_check) {
+            ESP_LOGW(TAG, "Checksum mismatch: expected 0x%04x, got 0x%04x", calculated_check, head->check);
+            goto recover;
+        }
+
+        // Check if we have the complete packet
+        uint16_t payload_size = head->size;
+        int channel = head->channel;
+        size_t total_packet_size = sizeof(struct header) + payload_size;
+
+        if (payload_size > MAX_PAYLOAD) {
+            ESP_LOGW(TAG, "Invalid payload size: %d", payload_size);
+            goto recover;
+        }
+
+        // If we don't have the complete packet yet, wait for more data
+        if ((buf_end - buf_start) < total_packet_size) {
+            ESP_LOGD(TAG, "Incomplete packet: got %d bytes, need %d bytes", (buf_end - buf_start), total_packet_size);
+            break;
+        }
+
+        // Got a complete packet, pass it to network
+        if (channel == 0) {
+            esp_netif_receive(netif, in_buf + buf_start + sizeof(struct header), payload_size, NULL);
+        } else {
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+            struct eppp_handle *handle = esp_netif_get_io_driver(netif);
+            struct eppp_uart *h = __containerof(handle, struct eppp_uart, parent);
+            if (h->parent.channel_rx) {
+                h->parent.channel_rx(netif, channel, in_buf + buf_start + sizeof(struct header), payload_size);
+            }
+#endif
+        }
+
+        // Advance start pointer past this packet
+        buf_start += total_packet_size;
+
+        // compact if we don't have enough space for 1x UART_BUF_SIZE
+        if (buf_start > (sizeof(in_buf) / 2) || (sizeof(in_buf) - buf_end) < UART_BUF_SIZE) {
+            if (buf_start < buf_end) {
+                size_t remaining_data = buf_end - buf_start;
+                memmove(in_buf, in_buf + buf_start, remaining_data);
+                buf_end = remaining_data;
+            } else {
+                buf_end = 0;
+            }
+            buf_start = 0;
+        }
+
+        continue;
+
+recover:
+        // Search for next HEADER_MAGIC occurrence
+        uint8_t *next_magic = memchr(in_buf + buf_start + 1, HEADER_MAGIC, buf_end - buf_start - 1);
+        if (next_magic) {
+            // Found next potential header, advance start to that position
+            buf_start = next_magic - in_buf;
+
+            // Check if we need to compact after recovery too
+            if (buf_start > (sizeof(in_buf) / 2) || (sizeof(in_buf) - buf_end) < UART_BUF_SIZE) {
+                if (buf_start < buf_end) {
+                    size_t remaining_data = buf_end - buf_start;
+                    memmove(in_buf, in_buf + buf_start, remaining_data);
+                    buf_end = remaining_data;
+                } else {
+                    buf_end = 0;
+                }
+                buf_start = 0;
+            }
+        } else {
+            // No more HEADER_MAGIC found, discard all data
+            buf_start = buf_end = 0;
+        }
+    }
+}
+#endif
+
+esp_err_t eppp_perform(esp_netif_t *netif)
+{
+    struct eppp_handle *handle = esp_netif_get_io_driver(netif);
+    struct eppp_uart *h = __containerof(handle, struct eppp_uart, parent);
+
+    uart_event_t event = {};
+    if (h->parent.stop) {
+        return ESP_ERR_TIMEOUT;
+    }
+
+    if (xQueueReceive(h->uart_event_queue, &event, pdMS_TO_TICKS(100)) != pdTRUE) {
+        return ESP_OK;
+    }
+    if (event.type == UART_DATA) {
+        size_t len;
+        uart_get_buffered_data_len(h->uart_port, &len);
+        if (len) {
+#ifdef CONFIG_EPPP_LINK_USES_PPP
+            static uint8_t buffer[UART_BUF_SIZE] = {};
+            len = uart_read_bytes(h->uart_port, buffer, UART_BUF_SIZE, 0);
+            ESP_LOG_BUFFER_HEXDUMP("ppp_uart_recv", buffer, len, ESP_LOG_DEBUG);
+            esp_netif_receive(netif, buffer, len, NULL);
+#else
+            // Read directly in process_packet to save one buffer
+            process_packet(netif, h->uart_port, len);
+#endif
+        }
+    } else {
+        ESP_LOGW(TAG, "Received UART event: %d", event.type);
+    }
+    return ESP_OK;
+}
+
+
+static esp_err_t post_attach(esp_netif_t *esp_netif, void *args)
+{
+    eppp_transport_handle_t h = (eppp_transport_handle_t)args;
+    ESP_RETURN_ON_FALSE(h, ESP_ERR_INVALID_ARG, TAG, "Transport handle cannot be null");
+    h->base.netif = esp_netif;
+
+    esp_netif_driver_ifconfig_t driver_ifconfig = {
+        .handle =  h,
+        .transmit = transmit,
+    };
+
+    ESP_RETURN_ON_ERROR(esp_netif_set_driver_config(esp_netif, &driver_ifconfig), TAG, "Failed to set driver config");
+    ESP_LOGI(TAG, "EPPP UART transport attached to EPPP netif %s", esp_netif_get_desc(esp_netif));
+    return ESP_OK;
+}
+
+eppp_transport_handle_t eppp_uart_init(struct eppp_config_uart_s *config)
+{
+    __attribute__((unused)) esp_err_t ret = ESP_OK;
+    ESP_RETURN_ON_FALSE(config, NULL, TAG, "Config cannot be null");
+    struct eppp_uart *h = calloc(1, sizeof(struct eppp_uart));
+    ESP_RETURN_ON_FALSE(h, NULL, TAG, "Failed to allocate eppp_handle");
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+    h->parent.channel_tx = transmit_channel;
+#endif
+    h->parent.base.post_attach = post_attach;
+    ESP_GOTO_ON_ERROR(init_uart(h, config), err, TAG, "Failed to init UART");
+    return &h->parent;
+err:
+    free(h);
+    return NULL;
+}
+
+void eppp_uart_deinit(eppp_transport_handle_t handle)
+{
+    struct eppp_uart *h = __containerof(handle, struct eppp_uart, parent);
+    deinit_uart(h);
+    free(h);
+}

components/eppp_link/examples/host/main/CMakeLists.txt

@@ -1,2 +1,6 @@
+if(CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL)
+    set(wifi_over_channels channel_wifi_station.c)
+endif()
 idf_component_register(SRCS app_main.c register_iperf.c
-                    INCLUDE_DIRS ".")
+                            ${wifi_over_channels}
+                       INCLUDE_DIRS ".")

components/eppp_link/examples/host/main/Kconfig.projbuild

@@ -26,10 +26,66 @@ menu "Example Configuration"
         help
             Init and run iperf console.
 
+    config EXAMPLE_SPI_HOST
+        int "SPI Host"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 1
+        range 0 2
+        help
+            SPI host to use (SPI1_HOST=0, SPI2_HOST=1, SPI3_HOST=2).
+
+    config EXAMPLE_SPI_MOSI_PIN
+        int "MOSI Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 23
+        range 0 39
+        help
+            Pin number of SPI MOSI.
+
+    config EXAMPLE_SPI_MISO_PIN
+        int "MISO Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 19
+        range 0 39
+        help
+            Pin number of SPI MISO.
+
+    config EXAMPLE_SPI_SCLK_PIN
+        int "SCLK Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 18
+        range 0 39
+        help
+            Pin number of SPI SCLK.
+
+    config EXAMPLE_SPI_CS_PIN
+        int "CS Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 5
+        range 0 39
+        help
+            Pin number of SPI CS.
+
+    config EXAMPLE_SPI_INTR_PIN
+        int "Interrupt Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 17
+        range 0 39
+        help
+            Pin number of SPI interrupt.
+
+    config EXAMPLE_SPI_FREQUENCY
+        int "SPI Frequency (Hz)"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 4000000
+        range 100000 80000000
+        help
+            SPI frequency in Hz.
+
     config EXAMPLE_UART_TX_PIN
         int "TXD Pin Number"
         depends on EPPP_LINK_DEVICE_UART
-        default 10
+        default 17
         range 0 31
         help
             Pin number of UART TX.
@@ -37,7 +93,7 @@ menu "Example Configuration"
     config EXAMPLE_UART_RX_PIN
         int "RXD Pin Number"
         depends on EPPP_LINK_DEVICE_UART
-        default 11
+        default 18
         range 0 31
         help
             Pin number of UART RX.
@@ -45,9 +101,19 @@ menu "Example Configuration"
     config EXAMPLE_UART_BAUDRATE
         int "Baudrate"
         depends on EPPP_LINK_DEVICE_UART
-        default 2000000
+        default 921600
         range 0 4000000
         help
             Baudrate used by the PPP over UART
 
+    config EXAMPLE_WIFI_OVER_EPPP_CHANNEL
+        bool "Use WiFi over EPPP channel"
+        default n
+        depends on EPPP_LINK_CHANNELS_SUPPORT && ESP_WIFI_REMOTE_ENABLED
+        help
+            Enable this option to use WiFi over EPPP channel.
+            If this option is enabled, the example will only start the Wi-Fi driver,
+            but the Wi-Fi netif will reside on client's end and will channel
+            the Rx and Tx data via EPPP channels.
+
 endmenu

components/eppp_link/examples/host/main/app_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -14,6 +14,7 @@
 #include "esp_netif.h"
 #include "eppp_link.h"
 #include "esp_log.h"
+#include "esp_check.h"
 #include "mqtt_client.h"
 #include "console_ping.h"
 
@@ -88,6 +89,7 @@ static void mqtt_app_start(void)
 }
 #endif // MQTT
 
+void station_over_eppp_channel(void *arg);
 
 void app_main(void)
 {
@@ -104,13 +106,24 @@ void app_main(void)
     eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
 #if CONFIG_EPPP_LINK_DEVICE_SPI
     config.transport = EPPP_TRANSPORT_SPI;
+    config.spi.is_master = true;
+    config.spi.host = CONFIG_EXAMPLE_SPI_HOST;
+    config.spi.mosi = CONFIG_EXAMPLE_SPI_MOSI_PIN;
+    config.spi.miso = CONFIG_EXAMPLE_SPI_MISO_PIN;
+    config.spi.sclk = CONFIG_EXAMPLE_SPI_SCLK_PIN;
+    config.spi.cs = CONFIG_EXAMPLE_SPI_CS_PIN;
+    config.spi.intr = CONFIG_EXAMPLE_SPI_INTR_PIN;
+    config.spi.freq = CONFIG_EXAMPLE_SPI_FREQUENCY;
 #elif CONFIG_EPPP_LINK_DEVICE_UART
     config.transport = EPPP_TRANSPORT_UART;
     config.uart.tx_io = CONFIG_EXAMPLE_UART_TX_PIN;
     config.uart.rx_io = CONFIG_EXAMPLE_UART_RX_PIN;
     config.uart.baud = CONFIG_EXAMPLE_UART_BAUDRATE;
+#elif CONFIG_EPPP_LINK_DEVICE_ETH
+    config.transport = EPPP_TRANSPORT_ETHERNET;
 #else
     config.transport = EPPP_TRANSPORT_SDIO;
+    config.sdio.is_host = true;
 #endif
     esp_netif_t *eppp_netif = eppp_connect(&config);
     if (eppp_netif == NULL) {
@@ -145,6 +158,9 @@ void app_main(void)
     // start console REPL
     ESP_ERROR_CHECK(console_cmd_start());
 
+#ifdef CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL
+    station_over_eppp_channel(eppp_netif);
+#endif
 #if CONFIG_EXAMPLE_MQTT
     mqtt_app_start();
 #endif

components/eppp_link/examples/host/main/channel_wifi_station.c

@@ -0,0 +1,185 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include <stdio.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+#include "esp_system.h"
+#include "esp_event.h"
+#include "esp_netif.h"
+#include "eppp_link.h"
+#include "esp_log.h"
+#include "esp_check.h"
+#include "esp_wifi_remote.h"
+
+#define CHAT_CHANNEL 1
+#define WIFI_CHANNEL 2
+
+typedef enum {
+    UNKNOWN,
+    HELLO,
+    START,
+    ERROR,
+} state_t;
+
+typedef struct context {
+    eppp_channel_fn_t transmit;
+    EventGroupHandle_t flags;
+    state_t state;
+    esp_netif_t *eppp;
+} context_t;
+
+#define HELLO_BIT BIT0
+#define START_BIT BIT1
+#define CONNECT_BIT BIT2
+#define SERVER_UP_BIT BIT3
+
+#define ALL_BITS (HELLO_BIT | START_BIT | CONNECT_BIT | SERVER_UP_BIT)
+
+static uint8_t s_wifi_mac_addr[6] = { 0 };
+static const char *TAG = "eppp_host_example_with_channels";
+
+esp_netif_t* esp_wifi_remote_create_default_sta(void);
+
+static void event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
+{
+    ESP_LOGI(TAG, "IP event_handler: event_base=%s event_id=%d", event_base, event_id);
+    if (event_base == IP_EVENT && event_id == IP_EVENT_STA_GOT_IP) {
+        ip_event_got_ip_t *event = (ip_event_got_ip_t *) event_data;
+        ESP_LOGI(TAG, "Got IP:" IPSTR, IP2STR(&event->ip_info.ip));
+    }
+}
+
+esp_err_t esp_wifi_remote_get_mac(wifi_interface_t ifx, uint8_t mac[6])
+{
+    if (ifx != WIFI_IF_STA) {
+        return ESP_ERR_INVALID_STATE;
+
+    }
+    for (int i = 0; i < sizeof(s_wifi_mac_addr); i++) {
+        if (s_wifi_mac_addr[i] == 0) {
+            return ESP_ERR_INVALID_STATE;
+        }
+    }
+    memcpy(mac, s_wifi_mac_addr, sizeof(s_wifi_mac_addr));
+    return ESP_OK;
+}
+
+static esp_err_t eppp_receive(esp_netif_t *netif, int nr, void *buffer, size_t len)
+{
+    context_t *ctx = eppp_get_context(netif);
+    if (nr == CHAT_CHANNEL) {
+        ESP_LOGI(TAG, "Received channel=%d len=%d %.*s", nr, (int)len, (int)len, (char *)buffer);
+        const char hello[] = "Hello client";
+        const char mac[] = "MAC: ";
+        const char connected[] = "Connected";
+        const char server_up[] = "Server up";
+        size_t mac_len = 5 /* MAC: */ + 6 * 2 /* 6 bytes per char */ + 5 /* : */ + 1 /* \0 */;
+        if (len == sizeof(server_up) && memcmp(buffer, server_up, len) == 0) {
+            if (ctx->state == UNKNOWN) {
+                ESP_LOGI(TAG, "Server is up");
+                ctx->state = HELLO;
+            } else {
+                ESP_LOGE(TAG, "Received server up in unexpected state %d", ctx->state);
+                ctx->state = ERROR;
+            }
+            xEventGroupSetBits(ctx->flags, SERVER_UP_BIT);
+        } else if (len == sizeof(hello) && memcmp(buffer, hello, len) == 0) {
+            if (ctx->state == HELLO) {
+                xEventGroupSetBits(ctx->flags, HELLO_BIT);
+            } else {
+                ESP_LOGE(TAG, "Received hello in unexpected state %d", ctx->state);
+                ctx->state = ERROR;
+            }
+        } else if (len == mac_len && memcmp(buffer, mac, 5) == 0) {
+            if (ctx->state == HELLO) {
+                uint8_t mac_addr[6];
+                sscanf((char *)buffer + 5, "%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8,
+                       &mac_addr[0], &mac_addr[1], &mac_addr[2], &mac_addr[3], &mac_addr[4], &mac_addr[5]);
+                ESP_LOGI(TAG, "Parsed MAC: %02x:%02x:%02x:%02x:%02x:%02x\n", mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);
+                memcpy(s_wifi_mac_addr, mac_addr, sizeof(s_wifi_mac_addr));
+                xEventGroupSetBits(ctx->flags, START_BIT);
+            } else {
+                ESP_LOGE(TAG, "Received MAC in unexpected state %d", ctx->state);
+                ctx->state = ERROR;
+            }
+        } else if (len == sizeof(connected) && memcmp(buffer, connected, len) == 0) {
+            if (ctx->state == START) {
+                xEventGroupSetBits(ctx->flags, CONNECT_BIT);
+            } else {
+                ESP_LOGE(TAG, "Received connected in unexpected state %d", ctx->state);
+                ctx->state = ERROR;
+            }
+        }
+    } else if (nr == WIFI_CHANNEL) {
+        ESP_LOGD(TAG, "Received WIFI channel=%d len=%d", nr, (int)len);
+        ESP_LOG_BUFFER_HEXDUMP("wifi-receive", buffer, len, ESP_LOG_VERBOSE);
+        return esp_wifi_remote_channel_rx(ctx->eppp, buffer, NULL, len);
+    } else {
+        ESP_LOGE(TAG, "Incorrect channel number %d", nr);
+        return ESP_FAIL;
+    }
+    return ESP_OK;
+}
+
+static esp_err_t wifi_transmit(void *h, void *buffer, size_t len)
+{
+    esp_netif_t *eppp = (esp_netif_t *)h;
+    context_t *ctx = eppp_get_context(eppp);
+    ESP_LOG_BUFFER_HEXDUMP("wifi-transmit", buffer, len, ESP_LOG_VERBOSE);
+    return ctx->transmit(eppp, WIFI_CHANNEL, buffer, len);
+}
+
+void esp_netif_destroy_wifi_remote(void *esp_netif);
+
+void station_over_eppp_channel(void *arg)
+{
+    __attribute__((unused)) esp_err_t ret;
+    esp_netif_t *wifi = NULL;
+    context_t ctx = {
+        .transmit = NULL,
+        .flags = NULL,
+        .state = UNKNOWN,
+        .eppp = (esp_netif_t *)arg
+    };
+    ESP_GOTO_ON_FALSE(ctx.eppp != NULL, ESP_FAIL, err, TAG, "Incorrect EPPP netif");
+    ESP_GOTO_ON_FALSE(ctx.flags = xEventGroupCreate(), ESP_FAIL, err, TAG, "Failed to create event group");
+    ESP_GOTO_ON_ERROR(eppp_add_channels(ctx.eppp, &ctx.transmit, eppp_receive, &ctx), err, TAG, "Failed to add channels");
+    ESP_GOTO_ON_FALSE(ctx.transmit, ESP_FAIL, err, TAG, "Channel tx function is not set");
+    ESP_GOTO_ON_ERROR(esp_wifi_remote_channel_set(WIFI_IF_STA, ctx.eppp, wifi_transmit), err, TAG, "Failed to set wifi channel tx function");
+    esp_event_handler_register(IP_EVENT, IP_EVENT_STA_GOT_IP, event_handler, &ctx);
+
+    while (1) {
+        EventBits_t bits = xEventGroupWaitBits(ctx.flags, ALL_BITS, pdTRUE, pdFALSE, pdMS_TO_TICKS(1000));
+        if (bits & HELLO_BIT) {
+            ESP_LOGI(TAG, "Hello done");
+            if (wifi == NULL) {
+                wifi = esp_wifi_remote_create_default_sta();
+            }
+            const char command[] = "Get MAC";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)command, sizeof(command));
+        } else if (bits & START_BIT) {
+            ctx.state = START;
+            ESP_LOGI(TAG, "Starting WIFI");
+            esp_event_post(WIFI_REMOTE_EVENT, WIFI_EVENT_STA_START, NULL, 0, 0);
+        } else if (bits & CONNECT_BIT) {
+            ESP_LOGI(TAG, "WIFI connected");
+            esp_event_post(WIFI_REMOTE_EVENT, WIFI_EVENT_STA_CONNECTED, NULL, 0, 0);
+        } else if ((bits & SERVER_UP_BIT) == SERVER_UP_BIT || ctx.state != START)  {
+            if (ctx.state == ERROR) {
+                esp_netif_destroy_wifi_remote(wifi);
+                wifi = NULL;
+                ESP_LOGI(TAG, "WiFi netif has been destroyed");
+            }
+            const char hello[] = "Hello server";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)hello, sizeof(hello));
+            ctx.state = HELLO;
+        }
+    }
+
+err:
+    vTaskDelete(NULL);
+}

components/eppp_link/examples/host/main/idf_component.yml

@@ -1,7 +1,7 @@
 dependencies:
-  espressif/iperf-cmd: "^0.1.1"
+  espressif/iperf-cmd: ^0.1.1
   espressif/eppp_link:
-    version: "*"
-    override_path: "../../.."
+    version: '*'
+    override_path: ../../..
   console_cmd_ping:
-    version: "*"
+    version: '*'

components/eppp_link/examples/host/sdkconfig.ci.1

@@ -0,0 +1,4 @@
+CONFIG_IDF_TARGET="esp32s3"
+CONFIG_EPPP_LINK_DEVICE_SPI=y
+CONFIG_EPPP_LINK_CHANNELS_SUPPORT=y
+CONFIG_EPPP_LINK_USES_PPP=y

components/eppp_link/examples/host/sdkconfig.ci.2

@@ -0,0 +1,3 @@
+CONFIG_IDF_TARGET="esp32c3"
+CONFIG_EPPP_LINK_DEVICE_UART=y
+CONFIG_EPPP_LINK_CHANNELS_SUPPORT=y

components/eppp_link/examples/host/sdkconfig.ci.eth

@@ -0,0 +1,2 @@
+CONFIG_IDF_TARGET="esp32"
+CONFIG_EPPP_LINK_DEVICE_ETH=y

components/eppp_link/examples/host/sdkconfig.ci.sdio

@@ -0,0 +1,2 @@
+CONFIG_IDF_TARGET="esp32p4"
+CONFIG_EPPP_LINK_DEVICE_SDIO=y

components/eppp_link/examples/host/sdkconfig.defaults

@@ -1,4 +1 @@
-CONFIG_LWIP_PPP_SUPPORT=y
-CONFIG_LWIP_PPP_SERVER_SUPPORT=y
 CONFIG_LWIP_PPP_VJ_HEADER_COMPRESSION=n
-CONFIG_LWIP_PPP_DEBUG_ON=y

components/eppp_link/examples/slave/main/CMakeLists.txt

@@ -1,2 +1,6 @@
-idf_component_register(SRCS "eppp_slave.c"
-                    INCLUDE_DIRS ".")
+if(CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL)
+    set(wifi_over_channels channel_wifi_station.c)
+endif()
+idf_component_register(SRCS eppp_slave.c
+                            ${wifi_over_channels}
+                       INCLUDE_DIRS ".")

components/eppp_link/examples/slave/main/Kconfig.projbuild

@@ -18,10 +18,66 @@ menu "Example Configuration"
         help
             Set the Maximum retry to avoid station reconnecting to the AP unlimited when the AP is really inexistent.
 
+    config EXAMPLE_SPI_HOST
+        int "SPI Host"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 1
+        range 0 2
+        help
+            SPI host to use (SPI1_HOST=0, SPI2_HOST=1, SPI3_HOST=2).
+
+    config EXAMPLE_SPI_MOSI_PIN
+        int "MOSI Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 23
+        range 0 39
+        help
+            Pin number of SPI MOSI.
+
+    config EXAMPLE_SPI_MISO_PIN
+        int "MISO Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 19
+        range 0 39
+        help
+            Pin number of SPI MISO.
+
+    config EXAMPLE_SPI_SCLK_PIN
+        int "SCLK Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 18
+        range 0 39
+        help
+            Pin number of SPI SCLK.
+
+    config EXAMPLE_SPI_CS_PIN
+        int "CS Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 5
+        range 0 39
+        help
+            Pin number of SPI CS.
+
+    config EXAMPLE_SPI_INTR_PIN
+        int "Interrupt Pin Number"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 17
+        range 0 39
+        help
+            Pin number of SPI interrupt.
+
+    config EXAMPLE_SPI_FREQUENCY
+        int "SPI Frequency (Hz)"
+        depends on EPPP_LINK_DEVICE_SPI
+        default 1000000
+        range 100000 80000000
+        help
+            SPI frequency in Hz.
+
     config EXAMPLE_UART_TX_PIN
         int "TXD Pin Number"
         depends on EPPP_LINK_DEVICE_UART
-        default 11
+        default 18
         range 0 31
         help
             Pin number of UART TX.
@@ -29,7 +85,7 @@ menu "Example Configuration"
     config EXAMPLE_UART_RX_PIN
         int "RXD Pin Number"
         depends on EPPP_LINK_DEVICE_UART
-        default 10
+        default 17
         range 0 31
         help
             Pin number of UART RX.
@@ -37,9 +93,19 @@ menu "Example Configuration"
     config EXAMPLE_UART_BAUDRATE
         int "Baudrate"
         depends on EPPP_LINK_DEVICE_UART
-        default 2000000
+        default 921600
         range 0 4000000
         help
             Baudrate used by the PPP over UART
 
+    config EXAMPLE_WIFI_OVER_EPPP_CHANNEL
+        bool "Use WiFi over EPPP channel"
+        default n
+        depends on EPPP_LINK_CHANNELS_SUPPORT
+        help
+            Enable this option to use WiFi over EPPP channel.
+            If this option is enabled, the example will only start the Wi-Fi driver,
+            but the Wi-Fi netif will reside on client's end and will channel
+            the Rx and Tx data via EPPP channels.
+
 endmenu

components/eppp_link/examples/slave/main/channel_wifi_station.c

@@ -0,0 +1,169 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include <stdio.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+#include "esp_system.h"
+#include "esp_event.h"
+#include "esp_netif.h"
+#include "eppp_link.h"
+#include "esp_log.h"
+#include "esp_check.h"
+#include "esp_private/wifi.h"
+
+#define CHAT_CHANNEL 1
+#define WIFI_CHANNEL 2
+
+typedef enum {
+    UNKNOWN,
+    HELLO,
+    START,
+    ERROR,
+} state_t;
+
+typedef struct context {
+    eppp_channel_fn_t transmit;
+    EventGroupHandle_t flags;
+    state_t state;
+    esp_netif_t *eppp;
+} context_t;
+
+#define HELLO_BIT BIT0
+#define START_BIT BIT1
+#define CONNECT_BIT BIT2
+#define DISCONNECT_BIT BIT3
+
+#define ALL_BITS (HELLO_BIT | START_BIT | CONNECT_BIT | DISCONNECT_BIT)
+
+static const char *TAG = "eppp_host_example_with_channels";
+static context_t *s_eppp_channel_ctx = NULL;
+
+static esp_err_t eppp_receive(esp_netif_t *netif, int nr, void *buffer, size_t len)
+{
+    context_t *ctx = eppp_get_context(netif);
+    if (nr == CHAT_CHANNEL) {
+        ESP_LOGI(TAG, "Received channel=%d len=%d %.*s", nr, (int)len, (int)len, (char *)buffer);
+        const char hello[] = "Hello server";
+        const char mac[] = "Get MAC";
+        if (len == sizeof(hello) && memcmp(buffer, hello, len) == 0) {
+            if (ctx->state == HELLO) {
+                xEventGroupSetBits(ctx->flags, HELLO_BIT);
+            } else {
+                ctx->state = ERROR;
+            }
+        } else if (len == sizeof(mac) && memcmp(buffer, mac, 5) == 0) {
+            if (ctx->state == HELLO) {
+                xEventGroupSetBits(ctx->flags, START_BIT);
+            } else {
+                ctx->state = ERROR;
+            }
+        }
+    } else if (nr == WIFI_CHANNEL) {
+        ESP_LOGD(TAG, "Received WIFI channel=%d len=%d", nr, (int)len);
+        ESP_LOG_BUFFER_HEXDUMP("wifi-receive", buffer, len, ESP_LOG_VERBOSE);
+        return esp_wifi_internal_tx(WIFI_IF_STA, buffer, len);
+    } else {
+        ESP_LOGE(TAG, "Incorrect channel number %d", nr);
+        return ESP_FAIL;
+    }
+    return ESP_OK;
+}
+
+static esp_err_t wifi_receive(void *buffer, uint16_t len, void *eb)
+{
+    s_eppp_channel_ctx->transmit(s_eppp_channel_ctx->eppp, WIFI_CHANNEL, buffer, len);
+    esp_wifi_internal_free_rx_buffer(eb);
+    return ESP_OK;
+}
+
+static void event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
+{
+    context_t *ctx = arg;
+    ESP_LOGI(TAG, "event_handler: event_base=%s event_id=%d", event_base, event_id);
+    if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
+        ESP_LOGI(TAG, "WIFI start event");
+        esp_wifi_connect();
+        xEventGroupSetBits(ctx->flags, CONNECT_BIT);
+    } else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
+        ESP_LOGI(TAG, "connect to the AP fail");
+        xEventGroupSetBits(ctx->flags, DISCONNECT_BIT);
+    }
+}
+
+
+static void init_wifi_driver(context_t *ctx)
+{
+    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
+    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
+    ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID,
+                                               event_handler, ctx));
+    wifi_config_t wifi_config = {
+        .sta = {
+            .ssid = CONFIG_ESP_WIFI_SSID,
+            .password = CONFIG_ESP_WIFI_PASSWORD,
+        },
+    };
+    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config));
+}
+
+void station_over_eppp_channel(void *arg)
+{
+    __attribute__((unused)) esp_err_t ret;
+    context_t ctx = {
+        .transmit = NULL,
+        .flags = NULL,
+        .state = UNKNOWN,
+        .eppp = (esp_netif_t *)arg
+    };
+    ESP_GOTO_ON_FALSE(ctx.flags = xEventGroupCreate(), ESP_FAIL, err, TAG, "Failed to create event group");
+    ESP_GOTO_ON_ERROR(eppp_add_channels(ctx.eppp, &ctx.transmit, eppp_receive, &ctx), err, TAG, "Failed to add channels");
+    ESP_GOTO_ON_FALSE(ctx.transmit, ESP_FAIL, err, TAG, "Channel tx function is not set");
+    init_wifi_driver(&ctx);
+
+    while (1) {
+        EventBits_t bits = xEventGroupWaitBits(ctx.flags, ALL_BITS, pdTRUE, pdFALSE, pdMS_TO_TICKS(1000));
+        if (bits & HELLO_BIT) {
+            ESP_LOGI(TAG, "Hello from client received");
+            const char hello[] = "Hello client";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)hello, sizeof(hello));
+        } else if (bits & START_BIT) {
+            ctx.state = START;
+            ESP_LOGI(TAG, "Starting WIFI");
+            uint8_t mac[6];
+            if (esp_wifi_get_mac(WIFI_IF_STA, mac) != ESP_OK) {
+                ESP_LOGE(TAG, "esp_wifi_get_mac failed");
+                ctx.state = ERROR;
+                continue;
+            }
+            char mac_data[5 /* MAC: */ + 6 * 2 /* 6 bytes per char */ + 5 /* : */ + 1 /* \0 */];
+            sprintf(mac_data, "MAC: %02x:%02x:%02x:%02x:%02x:%02x", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+            ESP_LOGI(TAG, "Sending MAC: %.*s", (int)sizeof(mac_data), mac_data);
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)mac_data, sizeof(mac_data));
+            ret = esp_wifi_start();
+            ESP_LOGI(TAG, "WIFI start result: %d", ret);
+            s_eppp_channel_ctx = &ctx;
+            esp_wifi_internal_reg_rxcb(WIFI_IF_STA, wifi_receive);
+        } else if (bits & CONNECT_BIT) {
+            ESP_LOGI(TAG, "WIFI connected");
+            const char connected[] = "Connected";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)connected, sizeof(connected));
+        } else if (bits & DISCONNECT_BIT) {
+            const char disconnected[] = "Disconnected";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)disconnected, sizeof(disconnected));
+        } else if (ctx.state != START) {
+            ctx.state = HELLO;
+            const char up[] = "Server up";
+            esp_wifi_disconnect();
+            esp_wifi_stop();
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)up, sizeof(up));
+        }
+    }
+
+err:
+    vTaskDelete(NULL);
+}

components/eppp_link/examples/slave/main/eppp_slave.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -11,12 +11,14 @@
 #include "esp_wifi.h"
 #include "esp_event.h"
 #include "esp_log.h"
+#include "esp_check.h"
 #include "nvs_flash.h"
 #include "eppp_link.h"
+#include "inttypes.h"
 
 static const char *TAG = "eppp_slave";
 
-#if CONFIG_SOC_WIFI_SUPPORTED
+#if defined(CONFIG_SOC_WIFI_SUPPORTED) && !defined(CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL)
 
 /* FreeRTOS event group to signal when we are connected*/
 static EventGroupHandle_t s_wifi_event_group;
@@ -27,12 +29,13 @@ static EventGroupHandle_t s_wifi_event_group;
 #define WIFI_CONNECTED_BIT BIT0
 #define WIFI_FAIL_BIT      BIT1
 
-
 static int s_retry_num = 0;
 
 static void event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
 {
+    ESP_LOGI(TAG, "event_handler: event_base=%s event_id=%" PRIi32, event_base, event_id);
     if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
+        ESP_LOGI(TAG, "WIFI start event");
         esp_wifi_connect();
     } else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
         if (s_retry_num < CONFIG_ESP_MAXIMUM_RETRY) {
@@ -55,9 +58,6 @@ void init_network_interface(void)
 {
     s_wifi_event_group = xEventGroupCreate();
 
-    ESP_ERROR_CHECK(esp_netif_init());
-
-    ESP_ERROR_CHECK(esp_event_loop_create_default());
     esp_netif_create_default_wifi_sta();
 
     wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
@@ -66,15 +66,15 @@ void init_network_interface(void)
     esp_event_handler_instance_t instance_any_id;
     esp_event_handler_instance_t instance_got_ip;
     ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT,
-                    ESP_EVENT_ANY_ID,
-                    &event_handler,
-                    NULL,
-                    &instance_any_id));
+                                                        ESP_EVENT_ANY_ID,
+                                                        &event_handler,
+                                                        NULL,
+                                                        &instance_any_id));
     ESP_ERROR_CHECK(esp_event_handler_instance_register(IP_EVENT,
-                    IP_EVENT_STA_GOT_IP,
-                    &event_handler,
-                    NULL,
-                    &instance_got_ip));
+                                                        IP_EVENT_STA_GOT_IP,
+                                                        &event_handler,
+                                                        NULL,
+                                                        &instance_got_ip));
 
     wifi_config_t wifi_config = {
         .sta = {
@@ -82,9 +82,9 @@ void init_network_interface(void)
             .password = CONFIG_ESP_WIFI_PASSWORD,
         },
     };
-    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA) );
-    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config) );
-    ESP_ERROR_CHECK(esp_wifi_start() );
+    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config));
+    ESP_ERROR_CHECK(esp_wifi_start());
 
     ESP_LOGI(TAG, "wifi_init_sta finished.");
 
@@ -110,12 +110,15 @@ void init_network_interface(void)
 }
 #else
 
+// If the SoC does not have WiFi capabilities, we can initialize a different network interface, this function is a placeholder for that purpose.
+// This function is also a no-op if EXAMPLE_WIFI_OVER_EPPP_CHANNEL==1, since the Wi-Fi network interface will live on the other peer (on the host side).
 void init_network_interface(void)
 {
-    // placeholder to initialize any other network interface if WiFi is not available
 }
 
-#endif // SoC WiFi capable chip
+#endif // SoC WiFi capable chip || WiFi over EPPP channel
+
+void station_over_eppp_channel(void *arg);
 
 void app_main(void)
 {
@@ -127,13 +130,21 @@ void app_main(void)
     }
     ESP_ERROR_CHECK(ret);
 
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
     init_network_interface();   // WiFi station if withing SoC capabilities (otherwise a placeholder)
-//    ESP_ERROR_CHECK(esp_netif_init());
-//    ESP_ERROR_CHECK(esp_event_loop_create_default());
 
     eppp_config_t config = EPPP_DEFAULT_SERVER_CONFIG();
 #if CONFIG_EPPP_LINK_DEVICE_SPI
     config.transport = EPPP_TRANSPORT_SPI;
+    config.spi.is_master = false;
+    config.spi.host = CONFIG_EXAMPLE_SPI_HOST;
+    config.spi.mosi = CONFIG_EXAMPLE_SPI_MOSI_PIN;
+    config.spi.miso = CONFIG_EXAMPLE_SPI_MISO_PIN;
+    config.spi.sclk = CONFIG_EXAMPLE_SPI_SCLK_PIN;
+    config.spi.cs = CONFIG_EXAMPLE_SPI_CS_PIN;
+    config.spi.intr = CONFIG_EXAMPLE_SPI_INTR_PIN;
+    config.spi.freq = CONFIG_EXAMPLE_SPI_FREQUENCY;
 #elif CONFIG_EPPP_LINK_DEVICE_UART
     config.transport = EPPP_TRANSPORT_UART;
     config.uart.tx_io = CONFIG_EXAMPLE_UART_TX_PIN;
@@ -148,5 +159,9 @@ void app_main(void)
         ESP_LOGE(TAG, "Failed to setup connection");
         return ;
     }
+#ifdef CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL
+    station_over_eppp_channel(eppp_netif);
+#else
     ESP_ERROR_CHECK(esp_netif_napt_enable(eppp_netif));
+#endif // CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL
 }

components/eppp_link/examples/slave/sdkconfig.ci.1

@@ -0,0 +1,4 @@
+CONFIG_IDF_TARGET="esp32s2"
+CONFIG_EPPP_LINK_DEVICE_SPI=y
+CONFIG_EPPP_LINK_CHANNELS_SUPPORT=y
+CONFIG_LWIP_PPP_VJ_HEADER_COMPRESSION=n

components/eppp_link/examples/slave/sdkconfig.ci.2

@@ -0,0 +1,4 @@
+CONFIG_IDF_TARGET="esp32c2"
+CONFIG_EPPP_LINK_DEVICE_UART=y
+CONFIG_LWIP_PPP_VJ_HEADER_COMPRESSION=n
+CONFIG_EPPP_LINK_USES_PPP=y

components/eppp_link/examples/slave/sdkconfig.ci.eth

@@ -0,0 +1,2 @@
+CONFIG_IDF_TARGET="esp32"
+CONFIG_EPPP_LINK_DEVICE_ETH=y

components/eppp_link/examples/slave/sdkconfig.ci.ipv4_only

@@ -0,0 +1 @@
+CONFIG_LWIP_IPV6=n

components/eppp_link/examples/slave/sdkconfig.ci.sdio

@@ -0,0 +1,2 @@
+CONFIG_IDF_TARGET="esp32c6"
+CONFIG_EPPP_LINK_DEVICE_SDIO=y

components/eppp_link/examples/slave/sdkconfig.defaults

@@ -1,6 +1,3 @@
 CONFIG_LWIP_IP_FORWARD=y
 CONFIG_LWIP_IPV4_NAPT=y
 CONFIG_LWIP_TCPIP_TASK_STACK_SIZE=4096
-CONFIG_LWIP_PPP_SUPPORT=y
-CONFIG_LWIP_PPP_SERVER_SUPPORT=y
-CONFIG_LWIP_PPP_VJ_HEADER_COMPRESSION=n

components/eppp_link/idf_component.yml

@@ -1,4 +1,4 @@
-version: 0.2.0
+version: 1.1.3
 url: https://github.com/espressif/esp-protocols/tree/master/components/eppp_link
 description: The component provides a general purpose PPP connectivity, typically used as WiFi-PPP router
 dependencies:

components/eppp_link/include/eppp_link.h

@@ -1,14 +1,18 @@
 /*
- * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 #define EPPP_DEFAULT_SERVER_IP() ESP_IP4TOADDR(192, 168, 11, 1)
 #define EPPP_DEFAULT_CLIENT_IP() ESP_IP4TOADDR(192, 168, 11, 2)
 
-#define EPPP_DEFAULT_CONFIG(our_ip, their_ip) { \
-    .transport = EPPP_TRANSPORT_UART,           \
+#define EPPP_DEFAULT_SPI_CONFIG()               \
     .spi = {                                    \
             .host = 1,                          \
             .mosi = 11,                         \
@@ -21,6 +25,8 @@
             .cs_ena_pretrans = 0,               \
             .cs_ena_posttrans = 0,              \
     },                                          \
+
+#define EPPP_DEFAULT_UART_CONFIG() \
     .uart = {   \
             .port = 1,          \
             .baud = 921600,     \
@@ -28,16 +34,58 @@
             .rx_io = 26,        \
             .queue_size = 16,   \
             .rx_buffer_size = 1024, \
+            .rts_io = -1,       \
+            .cts_io = -1,       \
+            .flow_control = 0,  \
     },                          \
+
+#define EPPP_DEFAULT_SDIO_CONFIG() \
     .sdio = {                                   \
             .width = 4,                         \
             .clk = 18,                          \
             .cmd = 19,                          \
-            .d0 = 49,                           \
-            .d1 = 50,                           \
+            .d0 = 14,                           \
+            .d1 = 15,                           \
             .d2 = 16,                           \
             .d3 = 17,           \
     },                          \
+
+#define EPPP_DEFAULT_ETH_CONFIG()   \
+    .ethernet = {                   \
+        .mdc_io = 23,               \
+        .mdio_io = 18,              \
+        .phy_addr = 1,              \
+        .rst_io= 5,                 \
+    },                              \
+
+#if CONFIG_EPPP_LINK_DEVICE_SPI
+#define EPPP_DEFAULT_TRANSPORT_CONFIG() EPPP_DEFAULT_SPI_CONFIG()
+#define EPPP_TRANSPORT_INIT(cfg)        eppp_spi_init(&cfg->spi)
+#define EPPP_TRANSPORT_DEINIT(handle)   eppp_spi_deinit(handle)
+
+#elif CONFIG_EPPP_LINK_DEVICE_UART
+#define EPPP_DEFAULT_TRANSPORT_CONFIG() EPPP_DEFAULT_UART_CONFIG()
+#define EPPP_TRANSPORT_INIT(cfg)        eppp_uart_init(&cfg->uart)
+#define EPPP_TRANSPORT_DEINIT(handle)   eppp_uart_deinit(handle)
+
+#elif CONFIG_EPPP_LINK_DEVICE_SDIO
+#define EPPP_DEFAULT_TRANSPORT_CONFIG() EPPP_DEFAULT_SDIO_CONFIG()
+#define EPPP_TRANSPORT_INIT(cfg)        eppp_sdio_init(&cfg->sdio)
+#define EPPP_TRANSPORT_DEINIT(handle)   eppp_sdio_deinit(handle)
+
+#elif CONFIG_EPPP_LINK_DEVICE_ETH
+#define EPPP_DEFAULT_TRANSPORT_CONFIG() EPPP_DEFAULT_ETH_CONFIG()
+#define EPPP_TRANSPORT_INIT(cfg)        eppp_eth_init(&cfg->ethernet)
+#define EPPP_TRANSPORT_DEINIT(handle)   eppp_eth_deinit(handle)
+
+#else
+#error Unexpeted transport
+#endif
+
+
+#define EPPP_DEFAULT_CONFIG(our_ip, their_ip) { \
+    .transport = EPPP_TRANSPORT_UART,           \
+    EPPP_DEFAULT_TRANSPORT_CONFIG()             \
     . task = {                  \
             .run_task = true,   \
             .stack_size = 4096, \
@@ -63,14 +111,15 @@ typedef enum eppp_transport {
     EPPP_TRANSPORT_UART,
     EPPP_TRANSPORT_SPI,
     EPPP_TRANSPORT_SDIO,
+    EPPP_TRANSPORT_ETHERNET,
 } eppp_transport_t;
 
 
 typedef struct eppp_config_t {
     eppp_transport_t transport;
-
     struct eppp_config_spi_s {
         int host;
+        bool is_master;
         int mosi;
         int miso;
         int sclk;
@@ -89,9 +138,13 @@ typedef struct eppp_config_t {
         int rx_io;
         int queue_size;
         int rx_buffer_size;
+        int rts_io;
+        int cts_io;
+        int flow_control;
     } uart;
 
     struct eppp_config_sdio_s {
+        bool is_host;
         int width;
         int clk;
         int cmd;
@@ -101,6 +154,13 @@ typedef struct eppp_config_t {
         int d3;
     } sdio;
 
+    struct eppp_config_ethernet_s {
+        int mdc_io;
+        int mdio_io;
+        int phy_addr;
+        int rst_io;
+    } ethernet;
+
     struct eppp_config_task_s {
         bool run_task;
         int stack_size;
@@ -116,20 +176,51 @@ typedef struct eppp_config_t {
 
 } eppp_config_t;
 
+typedef struct eppp_handle* eppp_transport_handle_t;
+
 esp_netif_t *eppp_connect(eppp_config_t *config);
 
 esp_netif_t *eppp_listen(eppp_config_t *config);
 
 void eppp_close(esp_netif_t *netif);
 
+/**
+ * @brief Initialize the EPPP link layer
+ * @param role
+ * @param config
+ * @return
+ */
 esp_netif_t *eppp_init(eppp_type_t role, eppp_config_t *config);
 
 void eppp_deinit(esp_netif_t *netif);
 
 esp_netif_t *eppp_open(eppp_type_t role, eppp_config_t *config, int connect_timeout_ms);
 
+esp_netif_t *eppp_netif_init(eppp_type_t role, eppp_transport_handle_t h, eppp_config_t *eppp_config);
+
 esp_err_t eppp_netif_stop(esp_netif_t *netif, int stop_timeout_ms);
 
 esp_err_t eppp_netif_start(esp_netif_t *netif);
 
+void eppp_netif_deinit(esp_netif_t *netif);
+
+/**
+ * @brief Performs EPPP link task operation (Used for task-less implementation)
+ * @param netif
+ * @return
+ *  - ESP_OK on success, ESP_FAIL on failure: the operation shall continue
+ *  - ESP_ERR_TIMEOUT indicates that the operation was requested to stop
+ */
 esp_err_t eppp_perform(esp_netif_t *netif);
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+typedef esp_err_t (*eppp_channel_fn_t)(esp_netif_t *netif, int nr, void *buffer, size_t len);
+
+esp_err_t eppp_add_channels(esp_netif_t *netif, eppp_channel_fn_t *tx, const eppp_channel_fn_t rx, void* context);
+
+void* eppp_get_context(esp_netif_t *netif);
+#endif // CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+
+#ifdef __cplusplus
+}
+#endif

components/eppp_link/include/eppp_transport_eth.h

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2023-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#pragma once
+
+#include "eppp_link.h"
+
+eppp_transport_handle_t eppp_eth_init(struct eppp_config_ethernet_s *config);
+void eppp_eth_deinit(eppp_transport_handle_t h);

components/eppp_link/include/eppp_transport_sdio.h

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#pragma once
+
+#include "eppp_link.h"
+
+eppp_transport_handle_t eppp_sdio_init(struct eppp_config_sdio_s *config);
+void eppp_sdio_deinit(eppp_transport_handle_t h);

components/eppp_link/include/eppp_transport_spi.h

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#pragma once
+
+#include "eppp_link.h"
+
+eppp_transport_handle_t eppp_spi_init(struct eppp_config_spi_s *config);
+void eppp_spi_deinit(eppp_transport_handle_t h);

components/eppp_link/include/eppp_transport_uart.h

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#pragma once
+
+#include "eppp_link.h"
+
+eppp_transport_handle_t eppp_uart_init(struct eppp_config_uart_s *config);
+void eppp_uart_deinit(eppp_transport_handle_t h);

components/eppp_link/test/test_app/CMakeLists.txt

@@ -1,7 +1,15 @@
 # The following four lines of boilerplate have to be in your project's CMakeLists
 # in this exact order for cmake to work correctly
 cmake_minimum_required(VERSION 3.16)
-set(EXTRA_COMPONENT_DIRS $ENV{IDF_PATH}/tools/unit-test-app/components)
 
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+
+if("${IDF_VERSION_MAJOR}.${IDF_VERSION_MINOR}" VERSION_GREATER_EQUAL "6.0")
+    set(test_component_dir $ENV{IDF_PATH}/tools/test_apps/components)
+else()
+    set(test_component_dir $ENV{IDF_PATH}/tools/unit-test-app/components)
+endif()
+
+set(EXTRA_COMPONENT_DIRS ${test_component_dir})
+
 project(test_app)

components/eppp_link/test/test_app/main/CMakeLists.txt

@@ -1,4 +1,10 @@
+if("${IDF_VERSION_MAJOR}.${IDF_VERSION_MINOR}" VERSION_GREATER "5.3")
+    set(driver_deps esp_driver_gpio esp_driver_spi esp_driver_uart esp_driver_sdio)
+else()
+    set(driver_deps driver)
+endif()
+
 idf_component_register(SRCS app_main.c
                     INCLUDE_DIRS "."
                     REQUIRES test_utils
-                    PRIV_REQUIRES unity nvs_flash esp_netif driver esp_event)
+                    PRIV_REQUIRES unity nvs_flash esp_netif esp_event ${driver_deps})

components/esp_dns/esp_dns_doh.c

@@ -177,6 +177,9 @@ esp_err_t esp_dns_http_event_handler(esp_http_client_event_t *evt)
     case HTTP_EVENT_REDIRECT:
         ESP_LOGE(TAG, "HTTP_EVENT_REDIRECT: Not supported(%d)", esp_http_client_get_status_code(evt->client));
         break;
+    default:
+        ESP_LOGD(TAG, "Other HTTP event: %d", evt->event_id);
+        break;
     }
     return ESP_OK;
 }

components/esp_modem/CMakeLists.txt

@@ -11,7 +11,12 @@ else()
                       src/esp_modem_uart.cpp
                       src/esp_modem_term_uart.cpp
                       src/esp_modem_netif.cpp)
-    set(dependencies driver esp_event esp_netif)
+    set(dependencies esp_event esp_netif)
+    if("${IDF_VERSION_MAJOR}.${IDF_VERSION_MINOR}" VERSION_GREATER "5.3")
+        list(APPEND dependencies esp_driver_uart)
+    else()
+        list(APPEND dependencies driver)
+    endif()
 endif()
 
 

components/esp_modem/Kconfig

@@ -103,4 +103,14 @@ menu "esp-modem"
             Set this to 'y' if you're making changes to the actual sources of
             the AT command definitions (typically in esp_modem_command_declare.inc)
 
+    config ESP_MODEM_USE_PPP_MODE
+        bool "Use PPP mode"
+        default y
+        select LWIP_PPP_SUPPORT
+        help
+            If enabled, the library can use PPP netif from lwip.
+            This is the default and most common setting.
+            But it's possible to disable it and use only AT commands,
+            in this case it's not required to enable LWIP_PPP_SUPPORT.
+
 endmenu

components/esp_modem/examples/ap_to_pppos/main/ap_to_pppos.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -100,10 +100,10 @@ void wifi_init_softap(void)
     ESP_ERROR_CHECK(esp_wifi_init(&cfg));
 
     ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT,
-                    ESP_EVENT_ANY_ID,
-                    &wifi_event_handler,
-                    NULL,
-                    NULL));
+                                                        ESP_EVENT_ANY_ID,
+                                                        &wifi_event_handler,
+                                                        NULL,
+                                                        NULL));
 
     wifi_config_t wifi_config = {
         .ap = {
@@ -120,7 +120,7 @@ void wifi_init_softap(void)
     }
 
     ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_AP));
-    ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_AP, &wifi_config));
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_AP, &wifi_config));
     ESP_ERROR_CHECK(esp_wifi_start());
 
     ESP_LOGI(TAG, "wifi_init_softap finished. SSID:%s password:%s channel:%d",

components/esp_modem/examples/modem_console/main/CMakeLists.txt

@@ -9,5 +9,4 @@ idf_component_register(SRCS "modem_console_main.cpp"
                             "${command_dir}/my_module_dce.cpp"
                             "httpget_handle.c"
                             "ping_handle.c"
-                       REQUIRES console esp_http_client nvs_flash
                        INCLUDE_DIRS "." "${command_dir}")

components/esp_modem/examples/modem_console/main/console_helper.cpp

@@ -63,13 +63,12 @@ void ConsoleCommand::RegisterCommand(const char *command, const char *help, cons
 
     arg_type end = { .end = arg_end(1) };
     arg_table.emplace_back(end);
-    const esp_console_cmd_t command_def = {
-        .command = command,
-        .help = help,
-        .hint = nullptr,
-        .func = command_func_pts[last_command],
-        .argtable = &arg_table[0]
-    };
+    esp_console_cmd_t command_def = { };
+    command_def.command = command;
+    command_def.help = help;
+    command_def.hint = nullptr;
+    command_def.func = command_func_pts[last_command];
+    command_def.argtable = &arg_table[0];
     ESP_ERROR_CHECK(esp_console_cmd_register(&command_def));
     last_command++;
     console_commands.emplace_back(this);

components/esp_modem/examples/modem_console/main/modem_console_main.cpp

@@ -21,6 +21,7 @@
 #include "cxx_include/esp_modem_dte.hpp"
 #include "esp_modem_config.h"
 #include "cxx_include/esp_modem_api.hpp"
+#include "esp_idf_version.h"
 #if defined(CONFIG_EXAMPLE_SERIAL_CONFIG_USB)
 #include "esp_modem_usb_config.h"
 #include "cxx_include/esp_modem_usb_api.hpp"
@@ -29,6 +30,12 @@
 #include "console_helper.hpp"
 #include "my_module_dce.hpp"
 
+#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(6, 0, 0)
+#define GET_WAKEUP_CAUSE() esp_sleep_get_wakeup_causes()
+#else
+#define GET_WAKEUP_CAUSE() esp_sleep_get_wakeup_cause()
+#endif
+
 #if defined(CONFIG_EXAMPLE_FLOW_CONTROL_NONE)
 #define EXAMPLE_FLOW_CONTROL ESP_MODEM_FLOW_CONTROL_NONE
 #elif defined(CONFIG_EXAMPLE_FLOW_CONTROL_SW)
@@ -208,7 +215,7 @@ extern "C" void app_main(void)
     esp_console_dev_uart_config_t uart_config = ESP_CONSOLE_DEV_UART_CONFIG_DEFAULT();
     ESP_ERROR_CHECK(esp_console_new_repl_uart(&uart_config, &repl_config, &s_repl));
 
-    switch (esp_sleep_get_wakeup_cause()) {
+    switch (GET_WAKEUP_CAUSE()) {
     case ESP_SLEEP_WAKEUP_TIMER:
         if (esp_modem::modem_mode::CMUX_MODE == mode_rtc) {
             ESP_LOGI(TAG, "Deep sleep reset\n");
@@ -428,7 +435,7 @@ extern "C" void app_main(void)
     const ConsoleCommand SetDeepSleep("set_deep_sleep", "Put esp32 to deep sleep", &deep_sleep_args, sizeof(deep_sleep_args), [&](ConsoleCommand * c) {
         int tout = c->get_int_of(&DeepSleepArgs::timeout);
         ESP_LOGI(TAG, "Entering deep sleep for %d sec", tout);
-        ESP_LOGI(TAG, "Wakeup Cause: %d ", esp_sleep_get_wakeup_cause());
+        ESP_LOGI(TAG, "Wakeup Cause: %d ", GET_WAKEUP_CAUSE());
         esp_deep_sleep(tout * 1000000);
         return 0;
     });

components/esp_modem/examples/modem_tcp_client/main/CMakeLists.txt

@@ -1,7 +1,11 @@
+set(module_dir "generic_module")
 if (CONFIG_EXAMPLE_MODEM_DEVICE_BG96)
     set(device_srcs sock_commands_bg96.cpp)
 elseif(CONFIG_EXAMPLE_MODEM_DEVICE_SIM7600)
     set(device_srcs sock_commands_sim7600.cpp)
+elseif(CONFIG_EXAMPLE_MODEM_DEVICE_ESPAT)
+    set(device_srcs sock_commands_espat.cpp)
+    set(module_dir "espat_module")
 endif()
 
 if(CONFIG_ESP_MODEM_ENABLE_DEVELOPMENT_MODE)
@@ -14,4 +18,4 @@ idf_component_register(SRCS "modem_client.cpp"
                             "${command_dir}/sock_dce.cpp"
                             "tcp_transport_at.cpp"
                             "${device_srcs}"
-                       INCLUDE_DIRS "." "${command_dir}")
+                       INCLUDE_DIRS "." "${command_dir}" "${module_dir}")

components/esp_modem/examples/modem_tcp_client/main/Kconfig.projbuild

@@ -18,8 +18,26 @@ menu "Example Configuration"
             bool "SIM7600"
             help
                 SIM7600 is Multi-Band LTE-TDD/LTE-FDD/HSPA+ and GSM/GPRS/EDGE module
+        config EXAMPLE_MODEM_DEVICE_ESPAT
+            bool "ESP-AT"
+            help
+                ESP-AT firmware for ESP32 modules with WiFi connectivity
     endchoice
 
+    if EXAMPLE_MODEM_DEVICE_ESPAT
+        config EXAMPLE_WIFI_SSID
+            string "WiFi SSID"
+            default "myssid"
+            help
+                SSID (network name) to connect to.
+
+        config EXAMPLE_WIFI_PASSWORD
+            string "WiFi Password"
+            default "mypassword"
+            help
+                WiFi password (WPA or WPA2).
+    endif
+
     config EXAMPLE_MODEM_APN
         string "Set MODEM APN"
         default "internet"

components/esp_modem/examples/modem_tcp_client/main/command/sock_dce.hpp

@@ -8,6 +8,7 @@
 #include "cxx_include/esp_modem_api.hpp"
 #include <cxx_include/esp_modem_dce_factory.hpp>
 #include "sock_commands.hpp"
+#include "sock_module.hpp"
 #include <sys/socket.h>
 
 #pragma  once
@@ -97,8 +98,8 @@ private:
     std::shared_ptr<esp_modem::DTE> &dte;
 };
 
-class DCE : public ::esp_modem::GenericModule {
-    using esp_modem::GenericModule::GenericModule;
+class DCE : public Module {
+    using Module::Module;
 public:
 
     /**

components/esp_modem/examples/modem_tcp_client/main/espat_module/sock_module.hpp

@@ -0,0 +1,24 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include "esp_modem_config.h"
+#include "cxx_include/esp_modem_api.hpp"
+
+#pragma  once
+
+namespace sock_dce {
+
+class Module: public esp_modem::GenericModule {
+    using esp_modem::GenericModule::GenericModule;
+public:
+
+    esp_modem::command_result sync() override;
+    esp_modem::command_result set_echo(bool on) override;
+    esp_modem::command_result set_pdp_context(esp_modem::PdpContext &pdp) override;
+
+};
+
+}

components/esp_modem/examples/modem_tcp_client/main/generate/sock_dce.hpp

@@ -8,6 +8,7 @@
 #include "cxx_include/esp_modem_api.hpp"
 #include <cxx_include/esp_modem_dce_factory.hpp>
 #include "sock_commands.hpp"
+#include "sock_module.hpp"
 #include <sys/socket.h>
 
 #pragma  once
@@ -97,8 +98,8 @@ private:
     std::shared_ptr<esp_modem::DTE> &dte;
 };
 
-class DCE : public ::esp_modem::GenericModule {
-    using esp_modem::GenericModule::GenericModule;
+class DCE : public Module {
+    using Module::Module;
 public:
 
 //  --- ESP-MODEM command module starts here ---

components/esp_modem/examples/modem_tcp_client/main/generic_module/sock_module.hpp

@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include "esp_modem_config.h"
+#include "cxx_include/esp_modem_api.hpp"
+
+#pragma  once
+
+namespace sock_dce {
+
+using Module = esp_modem::GenericModule;
+
+}

components/esp_modem/examples/modem_tcp_client/main/modem_client.cpp

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -23,8 +23,8 @@
 #include "tcp_transport_mbedtls.h"
 #include "tcp_transport_at.h"
 
-#define BROKER_URL "mqtt.eclipseprojects.io"
-#define BROKER_PORT 8883
+#define BROKER_URL "test.mosquitto.org"
+#define BROKER_PORT 1883
 
 
 static const char *TAG = "modem_client";
@@ -114,7 +114,7 @@ extern "C" void app_main(void)
     mqtt_config.broker.address.port = BROKER_PORT;
     mqtt_config.session.message_retransmit_timeout = 10000;
 #ifndef CONFIG_EXAMPLE_CUSTOM_TCP_TRANSPORT
-    mqtt_config.broker.address.uri = "mqtts://127.0.0.1";
+    mqtt_config.broker.address.uri = "mqtt://127.0.0.1";
     dce->start_listening(BROKER_PORT);
 #else
     mqtt_config.broker.address.uri = "mqtt://" BROKER_URL;
@@ -124,14 +124,14 @@ extern "C" void app_main(void)
     mqtt_config.network.transport = ssl;
 #endif
     esp_mqtt_client_handle_t mqtt_client = esp_mqtt_client_init(&mqtt_config);
-    esp_mqtt_client_register_event(mqtt_client, static_cast<esp_mqtt_event_id_t>(ESP_EVENT_ANY_ID), mqtt_event_handler, NULL);
+    esp_mqtt_client_register_event(mqtt_client, static_cast<esp_mqtt_event_id_t>(ESP_EVENT_ANY_ID), mqtt_event_handler, nullptr);
     esp_mqtt_client_start(mqtt_client);
 #ifndef CONFIG_EXAMPLE_CUSTOM_TCP_TRANSPORT
     if (!dce->connect(BROKER_URL, BROKER_PORT)) {
         ESP_LOGE(TAG, "Failed to start DCE");
         return;
     }
-    while (1) {
+    while (true) {
         while (dce->perform_sock()) {
             ESP_LOGV(TAG, "...performing");
         }

components/esp_modem/examples/modem_tcp_client/main/sock_commands_bg96.cpp

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -18,14 +18,14 @@ using namespace esp_modem;
 
 command_result net_open(CommandableIf *t)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     std::string out;
     auto ret = dce_commands::generic_get_string(t, "AT+QISTATE?\r", out, 1000);
     if (ret != command_result::OK) {
         return ret;
     }
     if (out.find("+QISTATE: 0") != std::string::npos) {
-        ESP_LOGV(TAG, "%s", out.data() );
+        ESP_LOGV(TAG, "%s", out.data());
         ESP_LOGD(TAG, "Already there");
         return command_result::FAIL;
     } else if (out.empty()) {
@@ -36,7 +36,7 @@ command_result net_open(CommandableIf *t)
 
 command_result net_close(CommandableIf *t)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     dce_commands::generic_command(t, "AT+QICLOSE=0\r", "OK", "ERROR", 10000);
     esp_modem::Task::Delay(1000);
     return dce_commands::generic_command(t, "AT+QIDEACT=1\r", "OK", "ERROR", 40000);
@@ -44,11 +44,11 @@ command_result net_close(CommandableIf *t)
 
 command_result tcp_open(CommandableIf *t, const std::string &host, int port, int timeout)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     std::string ip_open = R"(AT+QIOPEN=1,0,"TCP",")" + host + "\"," + std::to_string(port) + "\r";
     auto ret = dce_commands::generic_command(t, ip_open, "+QIOPEN: 0,0", "ERROR", timeout);
     if (ret != command_result::OK) {
-        ESP_LOGE(TAG, "%s Failed", __func__ );
+        ESP_LOGE(TAG, "%s Failed", __func__);
         return ret;
     }
     return command_result::OK;
@@ -56,27 +56,27 @@ command_result tcp_open(CommandableIf *t, const std::string &host, int port, int
 
 command_result tcp_close(CommandableIf *t)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     return dce_commands::generic_command(t, "AT+QICLOSE=0\r", "OK", "ERROR", 10000);
 }
 
 command_result tcp_send(CommandableIf *t, uint8_t *data, size_t len)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     assert(0);      // Remove when fix done
     return command_result::FAIL;
 }
 
 command_result tcp_recv(CommandableIf *t, uint8_t *data, size_t len, size_t &out_len)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     assert(0);      // Remove when fix done
     return command_result::FAIL;
 }
 
 command_result get_ip(CommandableIf *t, std::string &ip)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     std::string out;
     auto ret = dce_commands::generic_get_string(t, "AT+QIACT?\r", out, 5000);
     if (ret != command_result::OK) {
@@ -130,12 +130,15 @@ Responder::ret Responder::recv(uint8_t *data, size_t len)
     auto *recv_data = (char *)data;
     if (data_to_recv == 0) {
         const std::string_view head = "+QIRD: ";
-        auto head_pos = std::search(recv_data, recv_data + len, head.begin(), head.end());
-        if (head_pos == recv_data + len) {
+        const std::string_view recv_data_view = std::string_view(recv_data, len);
+        auto head_pos_found = recv_data_view.find(head);
+        if (head_pos_found == std::string_view::npos) {
             return ret::FAIL;
         }
 
+        auto *head_pos = recv_data + head_pos_found;
         auto next_nl = (char *)memchr(head_pos + head.size(), '\n', MIN_MESSAGE);
+
         if (next_nl == nullptr) {
             return ret::FAIL;
         }

components/esp_modem/examples/modem_tcp_client/main/sock_commands_espat.cpp

@@ -0,0 +1,366 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <charconv>
+#include <cstring>
+#include "sock_commands.hpp"
+#include "cxx_include/esp_modem_command_library_utils.hpp"
+#include "sock_dce.hpp"
+#include "sock_module.hpp"
+
+static const char *TAG = "sock_commands_espat";
+
+namespace sock_dce {
+
+using namespace esp_modem;
+
+command_result Module::sync()
+{
+    return dce_commands::generic_command_common(dte.get(), "AT\r\n");
+}
+
+command_result Module::set_echo(bool on)
+{
+    return dce_commands::generic_command_common(dte.get(), "ATE0\r\n");
+}
+
+command_result Module::set_pdp_context(PdpContext &pdp)
+{
+    return command_result::OK;
+}
+
+}
+
+namespace sock_commands {
+
+using namespace esp_modem;
+
+command_result net_open(CommandableIf *t)
+{
+    ESP_LOGV(TAG, "%s", __func__);
+
+    // Set WiFi mode to station
+    auto ret = dce_commands::generic_command(t, "AT+CWMODE=1\r\n", "OK", "ERROR", 5000);
+    if (ret != command_result::OK) {
+        ESP_LOGE(TAG, "Failed to set WiFi mode");
+        return ret;
+    }
+
+    // Connect to WiFi network
+    std::string wifi_cmd = "AT+CWJAP=\"" CONFIG_EXAMPLE_WIFI_SSID "\",\"" CONFIG_EXAMPLE_WIFI_PASSWORD "\"\r\n";
+    ret = dce_commands::generic_command(t, wifi_cmd, "OK", "ERROR", 15000);
+    if (ret != command_result::OK) {
+        ESP_LOGE(TAG, "Failed to connect to WiFi");
+        return ret;
+    }
+    ESP_LOGI(TAG, "WiFi connected successfully");
+
+    // Set passive receive mode (1) for better control
+    ret = set_rx_mode(t, 1);
+    if (ret != command_result::OK) {
+        ESP_LOGE(TAG, "Failed to set preferred Rx mode");
+        return ret;
+    }
+    return command_result::OK;
+}
+
+command_result net_close(CommandableIf *t)
+{
+    ESP_LOGV(TAG, "%s", __func__);
+    // Disconnect from WiFi
+    auto ret = dce_commands::generic_command(t, "AT+CWQAP\r\n", "OK", "ERROR", 5000);
+    if (ret != command_result::OK) {
+        ESP_LOGW(TAG, "Failed to disconnect WiFi (may already be disconnected)");
+    }
+    return command_result::OK;
+}
+
+command_result tcp_open(CommandableIf *t, const std::string &host, int port, int timeout)
+{
+    ESP_LOGV(TAG, "%s", __func__);
+
+    // Set single connection mode (just in case)
+    auto ret = dce_commands::generic_command(t, "AT+CIPMUX=0\r\n", "OK", "ERROR", 1000);
+    if (ret != command_result::OK) {
+        ESP_LOGW(TAG, "Failed to set single connection mode");
+    }
+
+    // Establish TCP connection
+    std::string tcp_cmd = "AT+CIPSTART=\"TCP\",\"" + host + "\"," + std::to_string(port) + "\r\n";
+    ret = dce_commands::generic_command(t, tcp_cmd, "CONNECT", "ERROR", timeout);
+    if (ret != command_result::OK) {
+        ESP_LOGE(TAG, "Failed to establish TCP connection to %s:%d", host.c_str(), port);
+        return ret;
+    }
+
+    ESP_LOGI(TAG, "TCP connection established to %s:%d", host.c_str(), port);
+    return command_result::OK;
+}
+
+command_result tcp_close(CommandableIf *t)
+{
+    ESP_LOGV(TAG, "%s", __func__);
+    return dce_commands::generic_command(t, "AT+CIPCLOSE\r\n", "CLOSED", "ERROR", 5000);
+}
+
+command_result tcp_send(CommandableIf *t, uint8_t *data, size_t len)
+{
+    ESP_LOGV(TAG, "%s", __func__);
+    // This function is not used in the current implementation
+    // Data sending is handled by the DCE responder
+    return command_result::FAIL;
+}
+
+command_result tcp_recv(CommandableIf *t, uint8_t *data, size_t len, size_t &out_len)
+{
+    ESP_LOGV(TAG, "%s", __func__);
+    // This function is not used in the current implementation
+    // Data receiving is handled by the DCE responder
+    return command_result::FAIL;
+}
+
+command_result get_ip(CommandableIf *t, std::string &ip)
+{
+    ESP_LOGV(TAG, "%s", __func__);
+    std::string out;
+    auto ret = dce_commands::at_raw(t, "AT+CIFSR\r\n", out, "OK", "ERROR", 5000);
+    if (ret != command_result::OK) {
+        return ret;
+    }
+
+    // Parse station IP from response
+    // Expected format: +CIFSR:STAIP,"192.168.1.100"
+    auto pos = out.find("+CIFSR:STAIP,\"");
+    if (pos != std::string::npos) {
+        pos += 14; // Move past "+CIFSR:STAIP,\""
+        auto end_pos = out.find("\"", pos);
+        if (end_pos != std::string::npos) {
+            ip = out.substr(pos, end_pos - pos);
+            ESP_LOGI(TAG, "Got IP address: %s", ip.c_str());
+            return command_result::OK;
+        }
+    }
+
+    ESP_LOGE(TAG, "Failed to parse IP address from response");
+    return command_result::FAIL;
+}
+
+command_result set_rx_mode(CommandableIf *t, int mode)
+{
+    ESP_LOGE(TAG, "%s", __func__);
+    // Active mode (0) sends data automatically, Passive mode (1) notifies about data for reading
+    std::string cmd = "AT+CIPRECVTYPE=" + std::to_string(mode) + "\r\n";
+    return dce_commands::generic_command(t, cmd, "OK", "ERROR", 1000);
+}
+
+} // sock_commands
+
+namespace sock_dce {
+
+void Responder::start_sending(size_t len)
+{
+    data_to_send = len;
+    send_stat = 0;
+    send_cmd("AT+CIPSEND=" + std::to_string(len) + "\r\n");
+}
+
+void Responder::start_receiving(size_t len)
+{
+    send_cmd("AT+CIPRECVDATA=" + std::to_string(len) + "\r\n");
+}
+
+bool Responder::start_connecting(std::string host, int port)
+{
+    std::string cmd = "AT+CIPSTART=\"TCP\",\"" + host + "\"," + std::to_string(port) + "\r\n";
+    send_cmd(cmd);
+    return true;
+}
+
+Responder::ret Responder::recv(uint8_t *data, size_t len)
+{
+    const int MIN_MESSAGE = 6;
+    size_t actual_len = 0;
+    auto *recv_data = (char *)data;
+
+    if (data_to_recv == 0) {
+        const std::string_view head = "+CIPRECVDATA:";
+
+        // Find the response header
+        auto head_pos = std::search(recv_data, recv_data + len, head.data(), head.data() + head.size(), [](char a, char b) {
+            return a == b;
+        });
+
+        if (head_pos == recv_data + len) {
+            return ret::FAIL;
+        }
+
+        // Find the end of the length field
+        auto next_comma = (char *)memchr(head_pos + head.size(), ',', MIN_MESSAGE);
+        if (next_comma == nullptr) {
+            return ret::FAIL;
+        }
+
+        // Parse the actual length
+        if (std::from_chars(head_pos + head.size(), next_comma, actual_len).ec == std::errc::invalid_argument) {
+            ESP_LOGE(TAG, "Cannot convert length");
+            return ret::FAIL;
+        }
+
+        ESP_LOGD(TAG, "Received: actual len=%zu", actual_len);
+        if (actual_len == 0) {
+            ESP_LOGD(TAG, "No data received");
+            return ret::FAIL;
+        }
+
+        if (actual_len > buffer_size) {
+            ESP_LOGE(TAG, "Data too large: %zu > %zu", actual_len, buffer_size);
+            return ret::FAIL;
+        }
+
+        // Move to the actual data after the comma
+        recv_data = next_comma + 1;
+        auto first_data_len = len - (recv_data - (char *)data);
+
+        if (actual_len > first_data_len) {
+            on_read(recv_data, first_data_len);
+            data_to_recv = actual_len - first_data_len;
+            return ret::NEED_MORE_DATA;
+        }
+        on_read(recv_data, actual_len);
+
+    } else if (data_to_recv > len) {    // Continue receiving
+        on_read(recv_data, len);
+        data_to_recv -= len;
+        return ret::NEED_MORE_DATA;
+
+    } else if (data_to_recv <= len) {    // Last chunk
+        on_read(recv_data, data_to_recv);
+        actual_len = data_to_recv;
+    }
+
+    // Look for "OK" marker after the data
+    char *ok_pos = nullptr;
+    if (actual_len + 1 + 2 /* OK */ <= len) {
+        ok_pos = (char *)memchr(recv_data + actual_len + 1, 'O', MIN_MESSAGE);
+        if (ok_pos == nullptr || ok_pos[1] != 'K') {
+            data_to_recv = 0;
+            return ret::FAIL;
+        }
+    }
+
+    // Reset and prepare for next receive
+    data_to_recv = 0;
+    return ret::OK;
+}
+
+Responder::ret Responder::send(uint8_t *data, size_t len)
+{
+    if (send_stat < 3) {
+        // Look for the '>' prompt
+        if (memchr(data, '>', len) == NULL) {
+            if (send_stat++ < 2) {
+                return ret::NEED_MORE_DATA;
+            }
+            ESP_LOGE(TAG, "Missed '>' prompt");
+            return ret::FAIL;
+        }
+
+        // Send the actual data
+        auto written = dte->write(&buffer[0], data_to_send);
+        if (written != data_to_send) {
+            ESP_LOGE(TAG, "Failed to write data: %d/%zu", written, data_to_send);
+            return ret::FAIL;
+        }
+        data_to_send = 0;
+        send_stat = 3;
+    }
+    return ret::IN_PROGRESS;
+}
+
+Responder::ret Responder::send(std::string_view response)
+{
+    if (send_stat == 3) {
+        if (response.find("SEND OK") != std::string::npos) {
+            send_stat = 0;
+            return ret::OK;
+        } else if (response.find("SEND FAIL") != std::string::npos) {
+            ESP_LOGE(TAG, "Send failed");
+            return ret::FAIL;
+        } else if (response.find("ERROR") != std::string::npos) {
+            ESP_LOGE(TAG, "Send error");
+            return ret::FAIL;
+        }
+    }
+    return ret::IN_PROGRESS;
+}
+
+Responder::ret Responder::connect(std::string_view response)
+{
+    if (response.find("CONNECT") != std::string::npos) {
+        ESP_LOGI(TAG, "TCP connected!");
+        return ret::OK;
+    }
+    if (response.find("ERROR") != std::string::npos) {
+        ESP_LOGE(TAG, "Failed to connect");
+        return ret::FAIL;
+    }
+    return ret::IN_PROGRESS;
+}
+
+Responder::ret Responder::check_async_replies(status state, std::string_view &response)
+{
+    ESP_LOGD(TAG, "Response: %.*s", static_cast<int>(response.size()), response.data());
+
+    // Handle WiFi status messages
+    if (response.find("WIFI CONNECTED") != std::string::npos) {
+        ESP_LOGI(TAG, "WiFi connected");
+    } else if (response.find("WIFI DISCONNECTED") != std::string::npos) {
+        ESP_LOGW(TAG, "WiFi disconnected");
+    }
+
+    // Handle TCP status messages
+    if (response.find("CONNECT") != std::string::npos && state == status::CONNECTING) {
+        return connect(response);
+    } else if (response.find("CLOSED") != std::string::npos) {
+        ESP_LOGW(TAG, "TCP connection closed");
+        return ret::FAIL;
+    }
+
+    // Handle data notifications in active mode (if we switch to it later)
+    if (response.find("+IPD,") != std::string::npos) {
+        uint64_t data_ready = 1;
+        write(data_ready_fd, &data_ready, sizeof(data_ready));
+        ESP_LOGD(TAG, "Data available notification");
+    }
+
+    if (state == status::SENDING) {
+        return send(response);
+    } else if (state == status::CONNECTING) {
+        return connect(response);
+    }
+
+    return ret::IN_PROGRESS;
+}
+
+Responder::ret Responder::process_data(status state, uint8_t *data, size_t len)
+{
+    if (state == status::SENDING) {
+        return send(data, len);
+    }
+    if (state == status::RECEIVING) {
+        return recv(data, len);
+    }
+    return ret::IN_PROGRESS;
+}
+
+status Responder::pending()
+{
+    // For ESP-AT, we don't need a pending check like BG96
+    // Just return current status
+    return status::SENDING;
+}
+
+} // sock_dce

components/esp_modem/examples/modem_tcp_client/sdkconfig.ci.espat

@@ -0,0 +1,2 @@
+CONFIG_IDF_TARGET="esp32"
+CONFIG_EXAMPLE_MODEM_DEVICE_ESPAT=y

components/esp_modem/examples/pppos_client/main/Kconfig.projbuild

@@ -185,7 +185,7 @@ menu "Example Configuration"
 
     config EXAMPLE_MQTT_BROKER_URI
         string "MQTT Broker URL"
-        default "mqtt://mqtt.eclipseprojects.io"
+        default "mqtt://test.mosquitto.org"
         help
             URL of the mqtt broker which this example connects to.
 

components/esp_modem/examples/pppos_client/sdkconfig.ci.sim800_c3

@@ -13,5 +13,5 @@ CONFIG_EXAMPLE_MODEM_PPP_APN="lpwa.vodafone.com"
 CONFIG_EXAMPLE_MQTT_TEST_TOPIC="/ci/esp-modem/pppos-client"
 CONFIG_EXAMPLE_PAUSE_NETIF_TO_CHECK_SIGNAL=y
 CONFIG_ESP_SYSTEM_PANIC_PRINT_HALT=y
-CONFIG_ESP32_PANIC_PRINT_HALT=y
 CONFIG_EXAMPLE_DETECT_MODE_BEFORE_CONNECT=y
+CONFIG_EXAMPLE_MQTT_BROKER_URI="mqtt://${CI_MQTT_BROKER_URI}"

components/esp_modem/examples/pppos_client/sdkconfig.ci.usb_a7670_s2

@@ -8,7 +8,6 @@ CONFIG_LWIP_PPP_ENABLE_IPV6=n
 CONFIG_EXAMPLE_SERIAL_CONFIG_USB=y
 CONFIG_EXAMPLE_MODEM_DEVICE_A7670=y
 CONFIG_EXAMPLE_MODEM_PPP_APN="lpwa.vodafone.com"
-CONFIG_EXAMPLE_MODEM_PPP_AUTH_NONE=y
 CONFIG_EXAMPLE_MQTT_TEST_TOPIC="/ci/esp-modem/pppos-client"
 CONFIG_ESP_SYSTEM_PANIC_PRINT_HALT=y
-CONFIG_ESP32_PANIC_PRINT_HALT=y
+CONFIG_EXAMPLE_MQTT_BROKER_URI="mqtt://${CI_MQTT_BROKER_URI}"

components/esp_modem/examples/simple_cmux_client/sdkconfig.ci.sim800_cmux

@@ -11,9 +11,8 @@ CONFIG_EXAMPLE_MODEM_DEVICE_SIM800=y
 CONFIG_EXAMPLE_MODEM_DEVICE_BG96=n
 CONFIG_EXAMPLE_MODEM_PPP_APN="lpwa.vodafone.com"
 CONFIG_ESP_SYSTEM_PANIC_PRINT_HALT=y
-CONFIG_ESP32_PANIC_PRINT_HALT=y
 CONFIG_COMPILER_CXX_EXCEPTIONS=y
 CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192
 CONFIG_EXAMPLE_CLOSE_CMUX_AT_END=y
 CONFIG_EXAMPLE_MQTT_TEST_TOPIC="/ci/esp-modem/pppos-client"
-CONFIG_BROKER_URI="mqtt://mqtt.eclipseprojects.io"
+CONFIG_BROKER_URI="mqtt://${CI_MQTT_BROKER_URI}"

components/esp_modem/include/cxx_include/esp_modem_dce_factory.hpp

@@ -62,12 +62,16 @@ class Creator {
 public:
     Creator(std::shared_ptr<DTE> dte, esp_netif_t *esp_netif): dte(std::move(dte)), device(nullptr), netif(esp_netif)
     {
+#ifdef CONFIG_ESP_MODEM_USE_PPP_MODE
         ESP_MODEM_THROW_IF_FALSE(netif != nullptr, "Null netif");
+#endif
     }
 
     Creator(std::shared_ptr<DTE> dte, esp_netif_t *esp_netif, std::shared_ptr<T_Module> dev): dte(std::move(dte)), device(std::move(dev)), netif(esp_netif)
     {
+#ifdef CONFIG_ESP_MODEM_USE_PPP_MODE
         ESP_MODEM_THROW_IF_FALSE(netif != nullptr, "Null netif");
+#endif
     }
 
     explicit Creator(std::shared_ptr<DTE> dte): dte(std::move(dte)), device(nullptr), netif(nullptr)

components/esp_modem/port/linux/esp_netif_linux/lwipopts.h

@@ -89,7 +89,7 @@
 
 #define MPPE_SUPPORT                    0
 
-#define PPP_MAXIDLEFLAG                 0
+#define PPP_MAXIDLEFLAG                 100
 
 #define PRINTPKT_SUPPORT                1
 #define PPP_PROTOCOLNAME                1

components/esp_modem/port/linux/esp_netif_linux/tun_io.c

@@ -104,7 +104,7 @@ static void ppp_link_status_cb(ppp_pcb *pcb, int err_code, void *ctx)
     }
 }
 
-static u32_t ppp_output_cb(struct ppp_pcb_s *pcb, const void *data, u32_t len, void *ctx)
+static u32_t ppp_output_cb(struct ppp_pcb_s *pcb, u8_t *data, u32_t len, void *ctx)
 {
     esp_netif_t *netif = (esp_netif_t *)ctx;
     if (netif->transmit) {

components/esp_modem/src/esp_modem_command_library.cpp

@@ -635,17 +635,40 @@ command_result get_network_registration_state(CommandableIf *t, int &state)
     }
 
     constexpr std::string_view pattern = "+CEREG: ";
-    int state_pos_start;
-    int state_pos_end;
-    if (out.find(pattern) == std::string::npos || (state_pos_start = out.find(',')) == std::string::npos) {
+
+    // Check if pattern exists and find its position
+    size_t pattern_pos = out.find(pattern);
+    if (pattern_pos == std::string::npos) {
         return command_result::FAIL;
     }
 
-    if (out.find(pattern) == std::string::npos || (state_pos_end = out.find(',', state_pos_start)) == std::string::npos) {
-        if (std::from_chars(out.data() + state_pos_start, out.data() + out.size(), state).ec == std::errc::invalid_argument) {
-            return command_result::FAIL;
+    // Find the first comma after the pattern
+    size_t state_pos_start = out.find(',', pattern_pos);
+    if (state_pos_start == std::string::npos) {
+        return command_result::FAIL;
+    }
+
+    // Find the end of the state value - either a second comma or end of line
+    size_t state_pos_end = out.find(',', state_pos_start + 1);
+    if (state_pos_end == std::string::npos) {
+        // No second comma found, look for end of line characters
+        state_pos_end = out.find('\r', state_pos_start);
+        if (state_pos_end == std::string::npos) {
+            state_pos_end = out.find('\n', state_pos_start);
         }
-    } else if (std::from_chars(out.data() + state_pos_start, out.data() + state_pos_end, state).ec == std::errc::invalid_argument) {
+        if (state_pos_end == std::string::npos) {
+            // No end delimiter found, use end of string
+            state_pos_end = out.size();
+        }
+    }
+
+    // Validate that we have a valid range to parse
+    if (state_pos_start + 1 >= state_pos_end) {
+        return command_result::FAIL;
+    }
+
+    // Extract state value (skip the comma)
+    if (std::from_chars(out.data() + state_pos_start + 1, out.data() + state_pos_end, state).ec == std::errc::invalid_argument) {
         return command_result::FAIL;
     }