| From foo@baz Fri Mar 16 15:43:16 CET 2018 |
| From: Hans de Goede <hdegoede@redhat.com> |
| Date: Wed, 22 Nov 2017 12:57:09 +0100 |
| Subject: HID: multitouch: Only look at non touch fields in first packet of a frame |
| |
| From: Hans de Goede <hdegoede@redhat.com> |
| |
| |
| [ 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@redhat.com> |
| Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> |
| Signed-off-by: Jiri Kosina <jkosina@suse.cz> |
| Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| 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) |