4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Hans de Goede <hdegoede@xxxxxxxxxx>
[ Upstream commit 55746d28d66860bccaae20a67b55b9d5db7c14af ]
Devices in "single finger hybrid mode" will send one report per finger,
on some devices only the first report of such a multi-packet frame will
contain a value for BTN_LEFT, in subsequent reports (if multiple fingers
are down) the value is always 0, causing hid-mt to report BTN_LEFT going
1 - 0 - 1 - 0 when pressing a clickpad and putting down a second finger.
This happens for example on USB 0603:0002 mt touchpads.
This commit fixes this by only reporting non touch fields for the first
packet of a (possibly) multi-packet frame.
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/hid/hid-multitouch.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -738,9 +738,11 @@ static int mt_touch_event(struct hid_dev
}
static void mt_process_mt_event(struct hid_device *hid, struct hid_field *field,
- struct hid_usage *usage, __s32 value)
+ struct hid_usage *usage, __s32 value,
+ bool first_packet)
{
struct mt_device *td = hid_get_drvdata(hid);
+ __s32 cls = td->mtclass.name;
__s32 quirks = td->mtclass.quirks;
struct input_dev *input = field->hidinput->input;
@@ -794,6 +796,15 @@ static void mt_process_mt_event(struct h
break;
default:
+ /*
+ * For Win8 PTP touchpads we should only look at
+ * non finger/touch events in the first_packet of
+ * a (possible) multi-packet frame.
+ */
+ if ((cls == MT_CLS_WIN_8 || cls == MT_CLS_WIN_8_DUAL) &&
+ !first_packet)
+ return;
+
if (usage->type)
input_event(input, usage->type, usage->code,
value);
@@ -813,6 +824,7 @@ static void mt_touch_report(struct hid_d
{
struct mt_device *td = hid_get_drvdata(hid);
struct hid_field *field;
+ bool first_packet;
unsigned count;
int r, n;
@@ -831,6 +843,7 @@ static void mt_touch_report(struct hid_d
td->num_expected = value;
}
+ first_packet = td->num_received == 0;
for (r = 0; r < report->maxfield; r++) {
field = report->field[r];
count = field->report_count;
@@ -840,7 +853,7 @@ static void mt_touch_report(struct hid_d
for (n = 0; n < count; n++)
mt_process_mt_event(hid, field, &field->usage[n],
- field->value[n]);
+ field->value[n], first_packet);
}
if (td->num_received >= td->num_expected)