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+Unl0kr
+======
+
+Proof-of-concept framebuffer-based disk unlocker for the initramfs based on [lvgl].
+
+__Disclaimer: Doesn't actually unlock anything 😜__
+
+# About
+
+This is an experiment that attempts to evaluate the fitness of [lvgl] to build a graphical user interface on the Linux framebuffer for unlocking encrypted hard drives during boot. It's neither functional nor meant to replace postmarketOS/osk-sdl. For background see postmarketOS/osk-sdl#121.
+
+# Status
+
+The biggest obstacle is input processing. [lv_drivers] provides an evdev interface (supporting touchscreens, pointer devices and keypads) and a [libinput] interface (supporting touchscreens only). Presently there is no support for full physical keyboards (short of using the SDL interface) and no automated device detection. Additonally, the drivers can currently not be used with multiple devices at the same time.
+
+## What works
+
+- Password-entry UI including on-screen keyboard on the framebuffer
+- Input device discovery for keyboards, mice and trackpads
+- On-screen keyboard control via mouse or trackpad (including cursor)
+- On-screen keyboard control via touchscreen (tested on PinePhone)
+- Halfway functional text input via keyboard devices (US layout only, works great on my laptop keyboard but drops keys on my Ergodox EZ)
+
+## To do
+
+... everything else ...
+
+# Upstreaming
+
+As far as feasible and sensible, [lvgl] and [lv_driver] fixes and enhancements are being upstreamed. Ideally all code outside of `main.c` should be contributed back but I'm not yet sure if that will be possible.
+
+Upstreamed contributions so far:
+
+- [Add support for pointer devices to libinput driver] (in review)
+- [Add support for keypads to libinput driver] (in review)
+
+# Operation
+
+## Dependencies
+
+- [lvgl] (git submodule / linked statically)
+- [lv_drivers] (git submodule / linked statically)
+- [libinput]
+
+## Testing
+
+For development and testing you can run the app in a VT. `sudo` is needed to access input device files.
+
+```
+$ make
+$ sudo chvt 2
+$ sudo ./unl0kr
+```
+
+# Acknowledgements
+
+The [lv_port_linux_frame_buffer] project served as a starting point for the codebase. The mouse cursor image was taken from [lv_sim_emscripten].
+
+# License
+
+Unl0kr is licensed under the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+[lvgl]: https://github.com/lvgl/lvgl
+[lv_drivers]: https://github.com/lvgl/lv_drivers
+[lv_port_linux_frame_buffer]: https://github.com/lvgl/lv_port_linux_frame_buffer]
+[lv_sim_emscripten]: https://github.com/lvgl/lv_sim_emscripten/blob/master/mouse_cursor_icon.c]
+[libinput]: https://gitlab.freedesktop.org/libinput/libinput
+[Add support for pointer devices to libinput driver]: https://github.com/lvgl/lv_drivers/pull/150
+[Add support for keypads to libinput driver]: https://github.com/lvgl/lv_drivers/pull/152