psmouse.synaptics_intertouch SYN1222 PNP0f13

Reporting as requested.  Setting the parameter appears to be working. 
If you need more info, please mail me directly.

System76 Gazelle upgrading from 4.9.34 to 4.14.2

First boot:
Nov 28 11:24:37 gazelle kernel: psmouse serio2: synaptics: queried max
coordinates: x [..5674], y [..4764]
Nov 28 11:24:37 gazelle kernel: psmouse serio2: synaptics: queried min
coordinates: x [1266..], y [1086..]
Nov 28 11:24:37 gazelle kernel: psmouse serio2: synaptics: The touchpad
can support a better bus than the too old PS/2 protocol. Make sure
MOUSE_PS2_SYNAPTICS_SMBUS and RMI4_SMB are enabled to get a better
touchpad experience.
Nov 28 11:24:37 gazelle kernel: psmouse serio2: synaptics: Touchpad
model: 1, fw: 8.2, id: 0x1e2b1, caps: 0xf00223/0x840300/0x26800/0x0,
board id: 3189, fw id: 2302754
Nov 28 11:24:37 gazelle kernel: input: SynPS/2 Synaptics TouchPad as
/devices/platform/i8042/serio2/input/input12

After enabling SMBUS:
Nov 28 11:54:44 gazelle kernel: psmouse serio2: synaptics: queried max
coordinates: x [..5674], y [..4764]
Nov 28 11:54:44 gazelle kernel: psmouse serio2: synaptics: queried min
coordinates: x [1266..], y [1086..]
Nov 28 11:54:44 gazelle kernel: psmouse serio2: synaptics: Your touchpad
(PNP: SYN1222 PNP0f13) says it can support a different bus. If i2c-hid
and hid-rmi are not used, you might want to try setting
psmouse.synaptics_intertouch to 1 and report this to
linux-input@vger.kernel.org.
Nov 28 11:54:44 gazelle kernel: psmouse serio2: synaptics: Touchpad
model: 1, fw: 8.2, id: 0x1e2b1, caps: 0xf00223/0x840300/0x26800/0x0,
board id: 3189, fw id: 2302754
Nov 28 11:54:44 gazelle kernel: input: SynPS/2 Synaptics TouchPad as
/devices/platform/i8042/serio2/input/input12

After adding parameter to boot line:
Nov 28 13:55:28 gazelle kernel: psmouse serio2: synaptics: queried max
coordinates: x [..5674], y [..4764]
Nov 28 13:55:28 gazelle kernel: psmouse serio2: synaptics: queried min
coordinates: x [1266..], y [1086..]
Nov 28 13:55:28 gazelle kernel: psmouse serio2: synaptics: Trying to set
up SMBus access
Nov 28 13:55:28 gazelle kernel: rmi4_smbus 5-002c: registering
SMbus-connected sensor
Nov 28 13:55:28 gazelle kernel: rmi4_f01 rmi4-00.fn01: found RMI device,
manufacturer: Synaptics, product: TM3189-002, fw id: 2302754
Nov 28 13:55:28 gazelle kernel: input: Synaptics TM3189-002 as
/devices/rmi4-00/input/input13

Cheers