From ccb51c2e3f0598934c3698f3645a3cb99add201c Mon Sep 17 00:00:00 2001 From: Jason Gerecke Date: Mon, 19 Jul 2021 13:55:32 -0700 Subject: 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 Signed-off-by: Jason Gerecke Signed-off-by: Jiri Kosina --- drivers/hid/wacom_wac.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) (limited to 'drivers/hid') diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c index ce9e8e9b48b6..3f992c9dca4d 100644 --- a/drivers/hid/wacom_wac.c +++ b/drivers/hid/wacom_wac.c @@ -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. -- cgit v1.2.3