HID: wacom: Avoid sending empty sync events

Empty sync events clutter up logs and are a waste of CPU cycles. We can
avoid sending mt_sync events if touch is disabled or a specific slot is
unused. We can avoid sending full sync events if no events were generated.

Signed-off-by: Ping Cheng <ping.cheng@wacom.com>
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Jason Gerecke 2021-07-19 13:55:32 -07:00 committed by Jiri Kosina
parent 5bed012886
commit ccb51c2e3f
1 changed files with 14 additions and 1 deletions

View File

@ -2551,8 +2551,17 @@ static void wacom_wac_finger_slot(struct wacom_wac *wacom_wac,
int slot;
slot = input_mt_get_slot_by_key(input, hid_data->id);
if (slot < 0)
if (slot < 0) {
return;
} else {
struct input_mt_slot *ps = &input->mt->slots[slot];
int mt_id = input_mt_get_value(ps, ABS_MT_TRACKING_ID);
if (!prox && mt_id < 0) {
// No data to send for this slot; short-circuit
return;
}
}
input_mt_slot(input, slot);
input_mt_report_slot_state(input, MT_TOOL_FINGER, prox);
@ -2696,6 +2705,10 @@ static void wacom_wac_finger_report(struct hid_device *hdev,
struct input_dev *input = wacom_wac->touch_input;
unsigned touch_max = wacom_wac->features.touch_max;
/* if there was nothing to process, don't send an empty sync */
if (wacom_wac->hid_data.num_expected == 0)
return;
/* If more packets of data are expected, give us a chance to
* process them rather than immediately syncing a partial
* update.