x11vnc with built-in multitouch injection for the Toon 1 and 2

Clicks and drags from a VNC client are written as Linux multitouch (MT protocol B) events straight into the touchscreen event device, so the Toon's qt-gui reacts to them like real finger touches.

What the patch does for Toon 2

Stock x11vnc's touch mode writes ABS_X, ABS_Y, ABS_PRESSURE, SYN_REPORT. Qt's evdevtouch plugin opens the SSD254x touchscreen as a multitouch device and only looks at ABS_MT_* events, so those single-touch events are ignored. The patch adds a UINPUT option mt that makes ptr_abs() emit exactly the sequence plus an explicit ABS_MT_SLOT:

press / drag:  ABS_MT_SLOT 0, ABS_MT_TRACKING_ID 1 (first report only),
               ABS_MT_POSITION_X, ABS_MT_POSITION_Y, ABS_MT_TOUCH_MAJOR 5,
               BTN_TOUCH 1 (first report only), ABS_X, ABS_Y, ABS_PRESSURE,
               SYN_REPORT
release:       ABS_MT_SLOT 0, ABS_MT_TRACKING_ID -1, BTN_TOUCH 0,
               ABS_MT_TOUCH_MAJOR 0, ABS_PRESSURE 0, SYN_REPORT

New UINPUT options (all optional except mt):

Option	Default	Meaning
mt	off	enable multitouch injection, implies touch and abs
mt_id=N	1	ABS_MT_TRACKING_ID used for the injected finger
mt_major=N	5	ABS_MT_TOUCH_MAJOR value while down
mt_slot=N	0	ABS_MT_SLOT to address, -1 sends no slot event

The patch also fixes the timestamp handling so the file compiles with 64-bit time_t C libraries (musl), and shutdown_uinput() releases a finger that is still down when x11vnc exits. x11vnc -help documents the option under -pipeinput UINPUT.

Missing screen updates: fix for Toon 1 and Toon 2

Qt eglfs on the i.MX6 GPU renders into two or three buffers inside /dev/fb0 and pans the display between them (the framebuffer's virtual height is a multiple of 600). Stock x11vnc with map:/dev/fb0@1024x600x32 only ever reads the first 1024x600 pixels, so whenever the display shows buffer 1 or 2 the VNC picture is stale while the Toon reacts to touches normally. The patch makes the map: rawfb code detect a Linux framebuffer device, map the whole video memory, and re-read the pan offset with FBIOGET_VSCREENINFO before every polling pass, so the VNC client always sees the buffer that is on the LCD. The log shows what was detected:

Installation on the Toon 1 and 2 (filenames from Toon 2 folder, replace with Toon 1 filename on that device)

mkdir -p /usr/local/lib/toon2-x11vnc-mt
copy x11vnc and start-toon2-mt-vnc.sh into that directory (scp/sftp)
chmod +x /usr/local/lib/toon2-x11vnc-mt/*

usage:

/usr/local/lib/toon2-x11vnc-mt/start-toon2-mt-vnc.sh start
/usr/local/lib/toon2-x11vnc-mt/start-toon2-mt-vnc.sh stop

The x11vnc log goes to /tmp/x11vnc.log.

Authentication is controlled by AUTH_OPTS at the top of the script. It is empty by default (no VNC password). Set it to -usepw to use the existing ~/.vnc/passwd like the old setup did. Do not comment out lines inside the backslash-continued x11vnc command; that silently drops the options after it.