This ACPI device exposed by the Chrome EC reports when a laptop-tablet convertible Chromebook (e.g., Google Pixelbook) is switched to tablet mode. Like on Linux, the reporting is via evdev:
-event3 SWITCH_TOGGLE +3.27s switch tablet-mode state 1 event3 SWITCH_TOGGLE +8.63s switch tablet-mode state 0
though it would be possible to add other kinds notifications I guess.
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