TB371FC GSI Patch

Magisk/APatch module source for the Lenovo TB371FC (Lenovo Legion Tab / Xiaoxin Pad Pro 12.7, Snapdragon 870) running a Treble GSI. It was developed against the Evolution X Android 16 GSI release dated 2025-09-02.

What it changes

• Forces a tablet form factor, landscape boot animation, and a 36dp tablet status bar.
• Removes the Wi-Fi tablet's visible Phone/SIM/carrier UI without deleting shared telephony framework files.
• Enables the real ambient-light sensor and a conservative brightness curve.
• Raises the broken GSI AOD/doze brightness default.
• Enables the TB371FC pen switch and four-channel speaker route.
• Keeps double-tap-to-wake enabled through deep idle, where this Lenovo touch driver can lose its write-only gesture flag.
• Keeps Android window-level blur enabled across boot.
• Installs a small foreground Hall-cover listener. It has no launcher entry; APatch root is used only for the sleep/wake key events.

Freeform/desktop windowing is intentionally disabled. This EvoX build shows the switch but its SystemUI/Shell path breaks minimization. The tablet taskbar and large-screen status bar remain enabled.

Install

1. Build the flashable module as described in Building.
2. Flash its ZIP from Magisk or APatch, then reboot.
3. On the first cover open/close event, allow the dev.monefiera.gsi.cover root request in APatch.

The cover helper starts after boot and after module updates. It deliberately does not expose a Google Launcher or Recents entry. It still appears in Android Settings > Apps, which is necessary for a real installed boot receiver.

Building

The repository does not ship extracted framework-res.apk, platform-signing keys, or private font files.

Required inputs:

• Android SDK Build Tools (tested with 34.0.0).
• The exact framework-res.apk from the target GSI.
• An overlay signing key/certificate accepted by that GSI.
• JDK 17 and Gradle 8.6 for the cover helper.
• Optional Topology Sans TTF files in assets/fonts/; these are deliberately ignored by Git. Omit them if you do not have redistribution rights. Building with them also requires Python fontTools; the build normalizes their Android vertical metrics to avoid excessive default line height.

Set the inputs and run:

export FRAMEWORK_RES_APK=/path/to/framework-res.apk
export RRO_PK8=/path/to/platform.pk8
export RRO_PEM=/path/to/platform.x509.pem
export ANDROID_BUILD_TOOLS=/path/to/android-sdk/build-tools/34.0.0
export JAVA_HOME=/path/to/jdk-17
./scripts/build-module.sh

The ZIP is written to dist/. The script compiles the static framework RRO against the supplied framework resources and packages the cover helper APK.

Device scope and safety

service.sh guards all kernel writes by ro.product.device=TB371FC. Do not flash it on another Y700-family tablet: its audio mixer indices are device and kernel specific. The telephony packages are disabled for user 0 rather than uninstalled, so they can be restored with pm enable.

The module cannot remove the bootloader's software integrity warning; that is outside Magisk/APatch's systemless mount scope.

References

• monefiera/Lenovo-Legion-Tab-GSI-FIX
• reindex-ot/LegionY700-GSI-Fix_MOD
• phhusson/treble_experimentations

License

MIT. The files under assets/fonts/, extracted framework APKs, and signing keys are intentionally not part of this repository and are not covered by this license.