wacom tablet intergration

[jleightcap]

integrate wacom hardware through libinput hooks.

the relevant functions:

libinput list-devices
libinput record $DEVICE

• [x] verify the above commands work with wacom hardware on rpi4 @cnorthway
• [x] verify expected libinput binaries exist when compiling libinput buildroot package
• [x] write xy stub (xy coordinate mock (/usr/share/test/wacom-xy-test.sh)
• [x] write xy script (/usr/bin/wacom-xy)
• [ ] design (i.e. just write down somewhere) what the button interface will look like. maybe just echoing "pressed!" or something. this then is read by the oscope driver.
• [ ] write button stub (button press mock (/usr/share/test/wacom-btn-test.sh)
• [ ] write button script (/usr/bin/wacom-btn)

[cnorthway]

first checkbox complete, output of libinput list-devices is slightly worrying, but the "libinput bug" doesn't seem to affect our ability to record from either device. Output copied below.

event1  - Wacom Intuos BT M Pad: libinput bug: missing tablet capabilities: pen resolution. Ignoring this device.
Device:           Wacom Intuos BT M Pen
Kernel:           /dev/input/event0
Group:            1
Seat:             seat0, default
Size:             216x135mm
Capabilities:     tablet 
Tap-to-click:     n/a
Tap-and-drag:     n/a
Tap drag lock:    n/a
Left-handed:      n/a
Nat.scrolling:    n/a
Middle emulation: n/a
Calibration:      n/a
Scroll methods:   none
Click methods:    none
Disable-w-typing: n/a
Accel profiles:   none
Rotation:         n/a

[jleightcap]

both button and coordinates verified to work.