Extend native Switch2Kit controller support to desktop platforms

.github/workflows/native-switch2kit.yml

@@ -14,15 +14,11 @@ jobs:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
         with:
           persist-credentials: false
-      - name: Check controller UI formatting
+      - name: Check exact-width SDL adapter capacity
         run: |
-          python3 -m venv "$RUNNER_TEMP/formatter"
-          "$RUNNER_TEMP/formatter/bin/pip" install 'clang-format==21.1.8'
-          "$RUNNER_TEMP/formatter/bin/clang-format" --dry-run --Werror \
-            Source/Core/DolphinQt/Config/ControllersPane.cpp \
-            Source/Core/DolphinQt/Config/GamecubeControllersWidget.cpp \
-            Source/Core/DolphinQt/Config/Mapping/MappingWindow.cpp \
-            Source/Core/DolphinQt/Config/Mapping/Switch2KitMapping.cpp
+          git submodule update --init Externals/Switch2Kit Externals/SDL/SDL
+          CXX=clang++ python3 Tools/test_switch2kit_capacity.py
+          CXX=g++ python3 Tools/test_switch2kit_capacity.py
       - run: python3 Tools/test_switch2kit.py
       - run: python3 Tools/test_switch2kit_autoconnect.py
       - run: python3 Tools/test_switch2kit_mapping.py --sanitize
@@ -77,7 +73,7 @@ jobs:
         run: brew install cmake ninja nasm automake libtool qt@6
       - name: Check source pin and integration
         run: |
-          test "$(git -C Externals/Switch2Kit rev-parse HEAD)" = a9d43b1f63d94f8844755a510bf6ecc876bc8c51
+          test "$(git -C Externals/Switch2Kit rev-parse HEAD)" = "$(git ls-tree HEAD Externals/Switch2Kit | awk '{print $3}')"
           python3 Tools/test_switch2kit.py
           python3 Tools/test_switch2kit_autoconnect.py
           python3 Tools/test_switch2kit_host.py --sanitize

.github/workflows/switch2kit-desktop.yml

@@ -0,0 +1,35 @@
+name: Switch2Kit desktop platforms
+on:
+  pull_request:
+  workflow_dispatch:
+permissions:
+  contents: read
+concurrency:
+  group: switch2kit-desktop-${{ github.ref }}
+  cancel-in-progress: true
+jobs:
+  source:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          persist-credentials: false
+      - name: Initialize the pinned controller SDK and SDL
+        run: git submodule update --init Externals/Switch2Kit Externals/SDL/SDL
+      - name: Archive the exact sources used by the controller integration
+        run: |
+          mkdir -p "$RUNNER_TEMP/switch2kit-source"
+          git archive HEAD -o "$RUNNER_TEMP/switch2kit-source/host.zip"
+          git -C Externals/Switch2Kit archive HEAD -o "$RUNNER_TEMP/switch2kit-source/sdk.zip"
+          git -C Externals/SDL/SDL archive HEAD -o "$RUNNER_TEMP/switch2kit-source/sdl.zip"
+          {
+            git rev-parse HEAD
+            git submodule status Externals/Switch2Kit Externals/SDL/SDL
+          } > "$RUNNER_TEMP/switch2kit-source/revisions.txt"
+      - uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02
+        with:
+          name: Switch2Kit-desktop-source
+          path: ${{ runner.temp }}/switch2kit-source
+          retention-days: 7
+          if-no-files-found: error

.github/workflows/switch2kit-linux.yml

@@ -0,0 +1,118 @@
+name: Switch2Kit Linux application
+on:
+  pull_request:
+  workflow_dispatch:
+permissions:
+  contents: read
+concurrency:
+  group: switch2kit-linux-${{ github.ref }}
+  cancel-in-progress: true
+jobs:
+  linux:
+    runs-on: ubuntu-24.04
+    container: swift:6.2.1-noble
+    timeout-minutes: 90
+    env:
+      DEBIAN_FRONTEND: noninteractive
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          persist-credentials: false
+          submodules: recursive
+      - name: Install native dependencies
+        run: |
+          apt-get update
+          apt-get install -y --no-install-recommends build-essential cmake ninja-build python3 pkg-config qt6-base-dev qt6-base-private-dev qt6-svg-dev libbluetooth-dev libevdev-dev libudev-dev libusb-1.0-0-dev libasound2-dev libpulse-dev libx11-dev libxi-dev libxrandr-dev libegl1-mesa-dev libgl1-mesa-dev libsystemd0 dbus xvfb xauth openbox wmctrl x11-utils
+          git config --global --add safe.directory "$PWD"
+      - name: Build and install the controller-enabled application
+        shell: bash
+        run: |
+          set -o pipefail
+          bash Tools/build-switch2kit-linux.sh 2>&1 | tee linux-build.log
+      - name: Execute controller policies
+        run: |
+          python3 Tools/test_switch2kit_mapping.py --sanitize
+          python3 Tools/test_switch2kit_host.py --sanitize
+          python3 Tools/test_switch2kit_autoconnect.py
+          python3 Tools/test_switch2kit_runtime.py
+      - name: Relocate, resolve native dependencies and launch the installed binary
+        shell: bash
+        run: |
+          set -euo pipefail
+          mv build-switch2kit/install "$RUNNER_TEMP/Dolphin-Switch2Kit-linux-x86_64"
+          app="$RUNNER_TEMP/Dolphin-Switch2Kit-linux-x86_64"
+          mv build-switch2kit "$RUNNER_TEMP/disabled-build-tree"
+          test -n "$(find "$app" -name libSwitch2KitC.so -print -quit)"
+          ldd "$app/bin/dolphin-emu" | tee linux-dependencies.log
+          ! grep -q 'not found' linux-dependencies.log
+          grep -F "$app" linux-dependencies.log | grep libSwitch2KitC
+          tar -C "$RUNNER_TEMP" -czf Dolphin-Switch2Kit-linux-x86_64.tar.gz Dolphin-Switch2Kit-linux-x86_64
+          mv "$app" "$RUNNER_TEMP/unavailable-staged-application"
+          dbus-run-session -- xvfb-run -a python3 Externals/Switch2Kit/tests/emulator-launch/linux.py dolphin \
+            "$PWD/Dolphin-Switch2Kit-linux-x86_64.tar.gz" --report "$PWD/linux-launch.json" \
+            --forbidden-root "$PWD" --forbidden-root "$RUNNER_TEMP/disabled-build-tree" \
+            --forbidden-root "$RUNNER_TEMP/unavailable-staged-application"
+      - name: Controller-enabled development build
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02
+        with:
+          name: Dolphin-Switch2Kit-linux-x86_64
+          path: Dolphin-Switch2Kit-linux-x86_64.tar.gz
+          retention-days: 14
+          if-no-files-found: error
+      - name: Native diagnostics
+        if: always()
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02
+        with:
+          name: Dolphin-Switch2Kit-linux-diagnostics
+          path: |
+            linux-*.log
+            linux-launch.json
+          retention-days: 7
+
+  disabled:
+    # A complete ordinary application build in an image without Swift. This is
+    # not a controller-enabled artifact and does not use the SDK build helper.
+    runs-on: ubuntu-24.04
+    container: ubuntu:24.04
+    timeout-minutes: 90
+    env:
+      DEBIAN_FRONTEND: noninteractive
+    steps:
+      - name: Install ordinary native dependencies without Swift
+        run: |
+          apt-get update
+          apt-get install -y --no-install-recommends git ca-certificates build-essential cmake ninja-build python3 pkg-config qt6-base-dev qt6-base-private-dev qt6-svg-dev libbluetooth-dev libevdev-dev libudev-dev libusb-1.0-0-dev libasound2-dev libpulse-dev libx11-dev libxi-dev libxrandr-dev libegl1-mesa-dev libgl1-mesa-dev libsystemd0 dbus
+          if command -v swift || command -v swiftc; then
+            echo 'The backend-disabled qualification image must not contain Swift.' >&2
+            exit 1
+          fi
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          persist-credentials: false
+          submodules: recursive
+      - name: Build the complete application with Switch2Kit disabled
+        shell: bash
+        run: |
+          set -euo pipefail
+          git config --global --add safe.directory "$PWD"
+          cmake -S . -B build-disabled -G Ninja -DCMAKE_BUILD_TYPE=Release \
+            -DENABLE_SWITCH2KIT=OFF -DENABLE_SDL=ON -DENABLE_QT=ON \
+            -DUSE_SYSTEM_SDL3=OFF -DENABLE_TESTS=OFF -DENABLE_VULKAN=OFF \
+            -DENABLE_AUTOUPDATE=OFF 2>&1 | tee disabled-configure.log
+          cmake --build build-disabled --target dolphin-emu --parallel 3 2>&1 | tee disabled-build.log
+          ldd build-disabled/Binaries/dolphin-emu | tee disabled-dependencies.log
+          ! grep -q 'not found' disabled-dependencies.log
+          ! grep -Ei 'Switch2Kit|libswift|libFoundation|libdispatch|libBlocksRuntime' disabled-dependencies.log
+          # Qt initializes for --version too. Keep this disabled-backend smoke
+          # probe isolated; the enabled archive still requires a real GUI below.
+          profile=$(mktemp -d)
+          trap 'rm -rf "$profile"' EXIT
+          HOME="$profile" XDG_CONFIG_HOME="$profile/config" XDG_CACHE_HOME="$profile/cache" \
+            QT_QPA_PLATFORM=offscreen build-disabled/Binaries/dolphin-emu --user "$profile/user" --version
+      - name: Backend-disabled build diagnostics
+        if: always()
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02
+        with:
+          name: Dolphin-without-Switch2Kit-linux-diagnostics
+          path: disabled-*.log
+          retention-days: 7

.github/workflows/switch2kit-windows.yml

@@ -0,0 +1,66 @@
+name: Switch2Kit Windows application
+on:
+  pull_request:
+  workflow_dispatch:
+permissions:
+  contents: read
+concurrency:
+  group: switch2kit-windows-${{ github.ref }}
+  cancel-in-progress: true
+jobs:
+  windows:
+    runs-on: windows-2025-vs2026
+    timeout-minutes: 120
+    env:
+      VCPKG_MAX_CONCURRENCY: 3
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1
+        with:
+          persist-credentials: false
+          submodules: recursive
+      - uses: compnerd/gha-setup-swift@397094e75494a93fa8d81db0268dbc8f5d6cf7c6
+        with:
+          # Swift 6.2 ships Clang 19, which the VS 2026 STL rejects.
+          swift-version: swift-6.3.3-release
+          swift-build: 6.3.3-RELEASE
+      - name: Build the complete controller-enabled application
+        shell: pwsh
+        run: |
+          & ./Tools/build-switch2kit-windows.ps1 2>&1 | Tee-Object windows-build.log
+          if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
+      - name: Stage and launch the application away from the build tree
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          $stage = Join-Path $env:RUNNER_TEMP 'Dolphin-Switch2Kit-windows-x86_64'
+          New-Item -ItemType Directory -Path $stage | Out-Null
+          # Robocopy follows directory junctions and copies linked resources.
+          robocopy 'build-switch2kit-windows/Binaries' $stage /E /NFL /NDL /NJH /NJS
+          if ($LASTEXITCODE -ge 8) { throw 'Application staging failed.' }
+          $global:LASTEXITCODE = 0
+          # Never distribute a developer/test profile. The supervisor seeds only
+          # its private extracted copy, after the distributable archive is made.
+          foreach ($profile in @('User', 'user', 'portable', 'portable.txt', 'settings.xml')) {
+            if (Test-Path (Join-Path $stage $profile)) { throw "Unexpected profile in application staging: $profile" }
+          }
+          Move-Item build-switch2kit-windows "$env:RUNNER_TEMP/disabled-build-tree"
+          Compress-Archive -Path $stage -DestinationPath 'Dolphin-Switch2Kit-windows-x86_64.zip'
+          Move-Item $stage "$env:RUNNER_TEMP/unavailable-staged-application"
+          & ./Tools/test_switch2kit_windows_launch.ps1 -Archive 'Dolphin-Switch2Kit-windows-x86_64.zip' -ForbiddenRoot "$PWD"
+          if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
+      - name: Controller-enabled development application
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02
+        with:
+          name: Dolphin-Switch2Kit-windows-x86_64
+          path: Dolphin-Switch2Kit-windows-x86_64.zip
+          retention-days: 14
+          if-no-files-found: error
+      - name: Native diagnostics
+        if: always()
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02
+        with:
+          name: Dolphin-Switch2Kit-windows-diagnostics
+          path: |
+            windows-*.log
+            windows-launch.json
+          retention-days: 7

CMake/DolphinSwitch2Kit.cmake

@@ -1,13 +1,16 @@
 # Optional host input only. Disabled builds do not require Swift or change deployment targets.
-option(ENABLE_SWITCH2KIT "Enable native Switch 2 controllers on macOS 15+" OFF)
+option(ENABLE_SWITCH2KIT "Enable native Switch 2 controllers" OFF)
 if(NOT ENABLE_SWITCH2KIT)
   return()
 endif()
-if(NOT APPLE OR NOT ENABLE_SDL OR NOT ENABLE_QT)
-  message(FATAL_ERROR "Switch2Kit requires macOS and the SDL and Qt backends")
+if(NOT (APPLE OR WIN32 OR CMAKE_SYSTEM_NAME STREQUAL "Linux") OR ANDROID)
+  message(FATAL_ERROR "Switch2Kit requires a macOS, Windows or Linux desktop host")
 endif()
-if(NOT CMAKE_OSX_DEPLOYMENT_TARGET OR CMAKE_OSX_DEPLOYMENT_TARGET VERSION_LESS 15.0)
-  message(FATAL_ERROR "Switch2Kit requires -DCMAKE_OSX_DEPLOYMENT_TARGET=15.0 or newer")
+if(NOT ENABLE_SDL OR NOT ENABLE_QT)
+  message(FATAL_ERROR "Switch2Kit requires the SDL and Qt backends")
+endif()
+if(APPLE AND (NOT CMAKE_OSX_DEPLOYMENT_TARGET OR CMAKE_OSX_DEPLOYMENT_TARGET VERSION_LESS 15.0))
+  message(FATAL_ERROR "Switch2Kit requires -DCMAKE_OSX_DEPLOYMENT_TARGET=15.0 or newer on macOS")
 endif()
 set(_switch2kit_source "${PROJECT_SOURCE_DIR}/Externals/Switch2Kit")
 if(NOT EXISTS "${_switch2kit_source}/Integrations/SDL3/CMakeLists.txt")