HID: hid-multitouch: ensure slots are initialized

In case a device does not provide the feature "Maximum Contact Count",
or set it at 0, the maxcontacts field may be at 0 while calling
input_mt_init_slots.

This patch ensures that hid-multitouch will allways report
ABS_MT_SLOT and ABS_MT_TRACKING_ID to the user space.

This corrects a bug found with some Ilitek devices that has been
integrated in 3.0-rc0.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Benjamin Tissoires 2011-06-21 15:01:53 +02:00 committed by Jiri Kosina
parent 5629937872
commit 50bc03ab5c

View File

@ -271,6 +271,8 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
}
return 1;
case HID_DG_CONTACTID:
if (!td->maxcontacts)
td->maxcontacts = MT_DEFAULT_MAXCONTACT;
input_mt_init_slots(hi->input, td->maxcontacts);
td->last_slot_field = usage->hid;
td->last_field_index = field->index;
@ -547,9 +549,6 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
if (ret)
goto fail;
if (!td->maxcontacts)
td->maxcontacts = MT_DEFAULT_MAXCONTACT;
td->slots = kzalloc(td->maxcontacts * sizeof(struct mt_slot),
GFP_KERNEL);
if (!td->slots) {