Add experimental on-printer HID erase-fix installer (review of #19)

.github/workflows/on-printer.yml

@@ -0,0 +1,57 @@
+name: On-printer HID tool
+on:
+  push:
+  pull_request:
+  workflow_call:
+permissions:
+  contents: read
+jobs:
+  build:
+    runs-on: ubuntu-24.04
+    timeout-minutes: 20
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          ref: ${{ github.sha }}
+          persist-credentials: false
+      - uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
+        with:
+          python-version: '3.12'
+      - name: Check embedded canonical payload and shell contracts
+        run: |
+          python on-printer/generate_payload.py --check
+          python -m unittest discover -s tests -p test_on_printer.py -v
+          sh -n on-printer/payload/installer.sh
+      - name: Install native build tools
+        run: |
+          rustup toolchain install 1.85.1 --profile minimal --component clippy --target armv7-unknown-linux-musleabihf
+          sudo apt-get update
+          sudo apt-get install -y gcc-arm-linux-gnueabihf qemu-user
+      - name: Test native protocol and compile static ARMv7 binary
+        env:
+          CARGO_TARGET_ARMV7_UNKNOWN_LINUX_MUSLEABIHF_LINKER: arm-linux-gnueabihf-gcc
+          CARGO_TARGET_ARMV7_UNKNOWN_LINUX_MUSLEABIHF_RUNNER: qemu-arm
+        run: |
+          cargo +1.85.1 test --locked --manifest-path on-printer/Cargo.toml
+          cargo +1.85.1 clippy --locked --manifest-path on-printer/Cargo.toml --all-targets -- -D warnings
+          cargo +1.85.1 test --locked --manifest-path on-printer/Cargo.toml --target armv7-unknown-linux-musleabihf
+          cargo +1.85.1 build --locked --manifest-path on-printer/Cargo.toml --release --target armv7-unknown-linux-musleabihf
+      - name: Check static linking and smoke-test executable
+        run: |
+          mkdir -p dist
+          cp on-printer/target/armv7-unknown-linux-musleabihf/release/cc2camera-hid dist/cc2camera-hid-armv7-linux
+          file dist/cc2camera-hid-armv7-linux
+          if readelf -l dist/cc2camera-hid-armv7-linux | grep -q INTERP; then exit 1; fi
+          if readelf -d dist/cc2camera-hid-armv7-linux | grep -q NEEDED; then exit 1; fi
+          qemu-arm dist/cc2camera-hid-armv7-linux --help
+          if qemu-arm dist/cc2camera-hid-armv7-linux install; then exit 1; fi
+          cd dist
+          sha256sum cc2camera-hid-armv7-linux > cc2camera-hid-armv7-linux.sha256
+          wc -c cc2camera-hid-armv7-linux
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: cc2camera-hid-armv7-linux
+          path: |
+            dist/cc2camera-hid-armv7-linux
+            dist/cc2camera-hid-armv7-linux.sha256
+          if-no-files-found: error

.github/workflows/release.yml

@@ -1,4 +1,4 @@
-name: Build release executable
+name: Build release executables
 
 on:
   release:
@@ -41,8 +41,13 @@ jobs:
             dist/cc2camera.exe.sha256
           if-no-files-found: error
 
+  on-printer:
+    uses: $/.github/workflows/on-printer.yml
+    permissions:
+      contents: read
+
   attach:
-    needs: build
+    needs: [build, on-printer]
     runs-on: ubuntu-latest
     timeout-minutes: 5
     permissions:
@@ -52,9 +57,16 @@ jobs:
         with:
           name: release-executable
           path: dist
+      - uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
+        with:
+          name: cc2camera-hid-armv7-linux
+          path: dist
       - name: Attach to the existing manually published release
         env:
           GH_TOKEN: ${{ github.token }}
           GH_REPO: ${{ github.repository }}
           RELEASE_TAG: ${{ github.event.release.tag_name }}
-        run: gh release upload "$RELEASE_TAG" dist/cc2camera.exe dist/cc2camera.exe.sha256
+        run: |
+          gh release upload "$RELEASE_TAG" \
+            dist/cc2camera.exe dist/cc2camera.exe.sha256 \
+            dist/cc2camera-hid-armv7-linux dist/cc2camera-hid-armv7-linux.sha256

.gitignore

@@ -23,3 +23,6 @@ Thumbs.db
 *.swp
 *~
 *.spec
+
+# Native on-printer builds
+on-printer/target/

README.md

@@ -19,6 +19,18 @@ dump to your device.
 > It has produced the expected result in two tested cases, but if you have any
 > doubts, independently audit the tools before using them on your hardware.
 
+## Already have a root shell on the printer?
+
+The [experimental on-printer HID installer](on-printer/README.md) can install
+and verify the startup fix while a working camera stays connected inside the
+CC2. It needs neither ADB nor Python on the printer. It does **not** export a
+backup or check safely erased configuration space; a failed write may require
+an external programmer. Read that guide's risks and prerequisites before use.
+It has been tested on a previously modified camera; volunteers are still needed
+for a first install on an unmodified, supported camera. If you try it, please
+[open an issue](https://github.com/OpenCentauri/cc2_camera_fix/issues/new) to share
+results, get help, and guide any needed tool adjustments.
+
 ## First identify your camera
 
 The known failure affects one 8 MiB flash-layout variant of the