From: Kerem Karabay <kekrby@xxxxxxxxx> This is needed to support Apple Touch Bars, where the contact ID is contained in fields with the HID_DG_TRANSDUCER_INDEX usage. Signed-off-by: Kerem Karabay <kekrby@xxxxxxxxx> Signed-off-by: Aditya Garg <gargaditya08@xxxxxxxx> --- drivers/hid/hid-multitouch.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 56fc78841..3e92789ed 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -635,7 +635,9 @@ static struct mt_report_data *mt_allocate_report_data(struct mt_device *td, if (field->logical == HID_DG_FINGER || td->hdev->group != HID_GROUP_MULTITOUCH_WIN_8) { for (n = 0; n < field->report_count; n++) { - if (field->usage[n].hid == HID_DG_CONTACTID) { + unsigned int hid = field->usage[n].hid; + + if (hid == HID_DG_CONTACTID || hid == HID_DG_TRANSDUCER_INDEX) { rdata->is_mt_collection = true; break; } @@ -814,6 +816,7 @@ static int mt_touch_input_mapping(struct hid_device *hdev, struct hid_input *hi, MT_STORE_FIELD(tip_state); return 1; case HID_DG_CONTACTID: + case HID_DG_TRANSDUCER_INDEX: MT_STORE_FIELD(contactid); app->touches_by_report++; return 1; -- 2.43.0