[PATCH 5.15 162/244] HID: multitouch: new device class fix Lenovo X12 trackpad sticky

From: Greg Kroah-Hartman
Date: Tue Aug 23 2022 - 06:18:09 EST


From: Tao Jin <tao-j@xxxxxxxxxxx>

[ Upstream commit 54eed5c7b938dc4ef6b14d4ee048bbdafdbce352 ]

The trackpad of the given device sends continuous report of pointers
status as per wxn8 spec. However, the spec did not clarify when the
fingers are lifted so fast that between the interval of two report
frames fingers on pad reduced from >=2 to 0. The second last report
contains >=2 fingers with tip state 1 and the last report contains only
1 finger with tip state 0. Although this can happen unfrequently, a
quick fix will be improve the consistency to 100%. A quick fix is to
disable MT_QUIRK_ALWAYS_VALID and enable MT_QUIRK_NOT_SEEN_MEANS_UP.

Test for hid-tools is added in [1]

In addition to this, I2C device 04CA:00B1 may also need similar class
but with MT_QUIRK_FORCE_MULTI_INPUT disabled (but it does not harm to
enable it on non-multi-input device either). The respective owner has
been notified and a patch may coming soon after test.

[1]: https://gitlab.freedesktop.org/libevdev/hid-tools/-/merge_requests/130

Signed-off-by: Tao Jin <tao-j@xxxxxxxxxxx>
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/hid/hid-multitouch.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index f382444dc2db..a14c48de4446 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -194,6 +194,7 @@ static void mt_post_parse(struct mt_device *td, struct mt_application *app);
#define MT_CLS_WIN_8_FORCE_MULTI_INPUT 0x0015
#define MT_CLS_WIN_8_DISABLE_WAKEUP 0x0016
#define MT_CLS_WIN_8_NO_STICKY_FINGERS 0x0017
+#define MT_CLS_WIN_8_FORCE_MULTI_INPUT_NSMU 0x0018

/* vendor specific classes */
#define MT_CLS_3M 0x0101
@@ -286,6 +287,15 @@ static const struct mt_class mt_classes[] = {
MT_QUIRK_WIN8_PTP_BUTTONS |
MT_QUIRK_FORCE_MULTI_INPUT,
.export_all_inputs = true },
+ { .name = MT_CLS_WIN_8_FORCE_MULTI_INPUT_NSMU,
+ .quirks = MT_QUIRK_IGNORE_DUPLICATES |
+ MT_QUIRK_HOVERING |
+ MT_QUIRK_CONTACT_CNT_ACCURATE |
+ MT_QUIRK_STICKY_FINGERS |
+ MT_QUIRK_WIN8_PTP_BUTTONS |
+ MT_QUIRK_FORCE_MULTI_INPUT |
+ MT_QUIRK_NOT_SEEN_MEANS_UP,
+ .export_all_inputs = true },
{ .name = MT_CLS_WIN_8_DISABLE_WAKEUP,
.quirks = MT_QUIRK_ALWAYS_VALID |
MT_QUIRK_IGNORE_DUPLICATES |
@@ -783,6 +793,7 @@ static int mt_touch_input_mapping(struct hid_device *hdev, struct hid_input *hi,
case HID_DG_CONFIDENCE:
if ((cls->name == MT_CLS_WIN_8 ||
cls->name == MT_CLS_WIN_8_FORCE_MULTI_INPUT ||
+ cls->name == MT_CLS_WIN_8_FORCE_MULTI_INPUT_NSMU ||
cls->name == MT_CLS_WIN_8_DISABLE_WAKEUP) &&
(field->application == HID_DG_TOUCHPAD ||
field->application == HID_DG_TOUCHSCREEN))
@@ -2033,7 +2044,7 @@ static const struct hid_device_id mt_devices[] = {
USB_DEVICE_ID_LENOVO_X1_TAB3) },

/* Lenovo X12 TAB Gen 1 */
- { .driver_data = MT_CLS_WIN_8_FORCE_MULTI_INPUT,
+ { .driver_data = MT_CLS_WIN_8_FORCE_MULTI_INPUT_NSMU,
HID_DEVICE(BUS_USB, HID_GROUP_MULTITOUCH_WIN_8,
USB_VENDOR_ID_LENOVO,
USB_DEVICE_ID_LENOVO_X12_TAB) },
--
2.35.1