The EC firmware correctly detects tablet mode, but does not disable the kb as the EC firmware packaged with the latest builds of chromeOS does. This appears to be handled correctly by the EC firmware bundled w/the chromeos builds (see for example board/voxel/sensors.c - chromiumos/platform/ec - Git at Google - my first clue was the last function “lid_angle_peripheral_enable(int enable)” at the end); Hopefully @MrChromebox or another person can confirm and investigate? I have the latest coreboot full UEFI firmware installed.
Also of interest is that using > sudo ectool motionsense list_activities returns an error (it should list the activities that montionsense performs… including enabling/disabling the kb)
Thanks!