On Mar 11 2016 or thereabouts, Dmitry Torokhov wrote:
> From: Benson Leung <ble...@chromium.org>
>
> When resetting a device (especially after power loss) it is unlikely
> that the firmware will keep the contact tracking data for the previous
> touches and will be able to reconcile it with the new contacts, so
> let's release all slots on reset resume as start anew.
>
> Signed-off-by: Benson Leung <ble...@chromium.org>
> Signed-off-by: Dmitry Torokhov <d...@chromium.org>
> ---
Seems good to me:
Reviewed-by: Benjamin Tissoires <benjamin.tissoi...@redhat.com>
Cheers,
Benjamin
> drivers/hid/hid-multitouch.c | 22 ++++++++++++++++++++++
> 1 file changed, 22 insertions(+)
>
> diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
> index 6adb788..e24e33c 100644
> --- a/drivers/hid/hid-multitouch.c
> +++ b/drivers/hid/hid-multitouch.c
> @@ -1148,8 +1148,30 @@ static int mt_probe(struct hid_device *hdev, const
> struct hid_device_id *id)
> }
>
> #ifdef CONFIG_PM
> +static void mt_release_contacts(struct hid_device *hid)
> +{
> + struct hid_input *hidinput;
> +
> + list_for_each_entry(hidinput, &hid->inputs, list) {
> + struct input_dev *input_dev = hidinput->input;
> + struct input_mt *mt = input_dev->mt;
> + int i;
> +
> + if (mt) {
> + for (i = 0; i < mt->num_slots; i++) {
> + input_mt_slot(input_dev, i);
> + input_mt_report_slot_state(input_dev,
> + MT_TOOL_FINGER,
> + false);
> + }
> + input_sync(input_dev);
> + }
> + }
> +}
> +
> static int mt_reset_resume(struct hid_device *hdev)
> {
> + mt_release_contacts(hdev);
> mt_set_maxcontacts(hdev);
> mt_set_input_mode(hdev);
> return 0;
> --
> 2.7.0.rc3.207.g0ac5344
>
>
> --
> Dmitry
