Hello, The Surface 3 Type Cover (non-Pro) does not work. Replacing in drivers/hid/hid-ids.h, the ID of Surface Pro 3 Type Cover (0x07dc) to the ID of Surface Pro 3 Type Cover (0x07de) is working Best regards.
I've submitted a patch for this to the linux-input ML here: http://www.spinics.net/lists/linux-input/msg39881.html
Was committed upstream in commit 0439de75d32c249bd9f5824ffd5e40c4c2109d77
This bug should be marked as closed.