• When TOHKBD base is attached to the phone for very first time
  • NFC ID is read by tohd and subbmitted to Jolla Store
  • Store install required packages automatically
  • During installation, EEPROM contents of TOHKBD are compared to certain vid/pid, and if they match, daemon is started
• After this, everytime TOHKBD base is attached to the phone, EEPROM contents are checked by udev rule, which starts daemon
• When daemon is started it creates a uinput device which is used to send key-events to system
• When the keyboard part is connected to the base, interrupt is generated which triggers followig sequence:
  • power-up keyboard and check can we communicate over I2C with keyboard chip. If comms test fails, shutdown keyboard.
  • send SW_KEYPAD_SLIDE event (keypad opened), which is registered by mce to turn display on
  • Show a notification that keyboard is connected
  • Change virtual keyboard layout to minimal (done through tohkbd2-user daemon which writes/reads dconf)
  • Force screen orientation to landscape
• Keyboard presense is checked every 2 secs. If comms test fails:
  • shutdown keyboard
  • send SW_KEYPAD_SLIDE event (keypad closed)
  • show notification that keyboard is removed
  • change virtual keyboard layout back to what it was before connecting keyboard
• When key is pressed on keyboard:
  • Interrupt is generated
  • daemon reads input report from keyboard chip over I2C and processes it
  • If a valid key was pressed, this is sent by uinput device to the system
  • some of keys have special function, like starting a application. these are processed in the daemon.

mer-obs https://build.merproject.org/project/show/home:kimmoli:tohs

 devel-su
 ssu ar tohs http://repo.merproject.org/obs/home:/kimmoli:/tohs/sailfish_latest_armv7hl
 ssu ur
 pkcon repo-set-data tohs refresh-now true
 pkcon install harbour-ambience-tohkbd2

• TCA8424 datasheet: http://www.ti.com/lit/ds/symlink/tca8424.pdf
• TCA8424 evaluation module user's guide: www.ti.com/lit/ug/scdu004/scdu004.pdf