[PATCH] Input: synaptics - enable InterTouch for ThinkPad X1E/P1 2nd gen

With the new RMI4 F3A support posted yesterday, this appears to maybe
work, with a bootloader warning in dmesg:

    psmouse serio1: synaptics: queried max coordinates: x [..5678], y [..4690]
    psmouse serio1: synaptics: queried min coordinates: x [1266..], y [1160..]
    psmouse serio1: synaptics: Trying to set up SMBus access
    rmi4_smbus 0-002c: registering SMbus-connected sensor
--> rmi4_f34 rmi4-00.fn34: rmi_f34v7_probe: Unrecognized bootloader version
--> rmi4_f34: probe of rmi4-00.fn34 failed with error -22
    rmi4_f01 rmi4-00.fn01: found RMI device, manufacturer: Synaptics, product: TM3512-010, fw id: 2956703
    input: Synaptics TM3512-010 as /devices/rmi4-00/input/input91
    serio: RMI4 PS/2 pass-through port at rmi4-00.fn03
    psmouse serio4: trackpoint: Elan TrackPoint firmware: 0x11, buttons: 3/3
    input: TPPS/2 Elan TrackPoint as /devices/rmi4-00/rmi4-00.fn03/serio4/input/input92

Cc: Lyude Paul <lyude@redhat.com>
Cc: Vincent Huang <redacted>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
 drivers/input/mouse/synaptics.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index 8a54efd6eb95..9d6fec84047b 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c

@@ -180,6 +180,7 @@ static const char * const smbus_pnp_ids[] = {
 	"LEN0096", /* X280 */
 	"LEN0097", /* X280 -> ALPS trackpoint */
 	"LEN0099", /* X1 Extreme 1st */
+	"LEN0402", /* X1 Extreme 2nd */
 	"LEN009b", /* T580 */
 	"LEN200f", /* T450s */
 	"LEN2044", /* L470  */

-- 
2.28.0