From: Jason Gerecke jason.gerecke@wacom.com
The Bluetooth interface of the 2nd-gen Intuos Pro batches together four independent "frames" of finger data into a single report. Each frame is essentially equivalent to a single USB report, with the up-to-10 fingers worth of information being spread across two frames. At the moment the driver only calls `input_sync` after processing all four frames have been processed, which can result in the driver sending multiple updates for a single slot within the same SYN_REPORT. This can confuse userspace, so modify the driver to sync more often if necessary (i.e., after reporting the state of all fingers).
Fixes: 4922cd26f0 ("HID: wacom: Support 2nd-gen Intuos Pro's Bluetooth classic interface") Cc: stable@vger.kernel.org # 4.11+ Signed-off-by: Jason Gerecke jason.gerecke@wacom.com --- drivers/hid/wacom_wac.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c index e848445236d8..09b8e4aac82f 100644 --- a/drivers/hid/wacom_wac.c +++ b/drivers/hid/wacom_wac.c @@ -1371,11 +1371,17 @@ static void wacom_intuos_pro2_bt_touch(struct wacom_wac *wacom) if (wacom->num_contacts_left <= 0) { wacom->num_contacts_left = 0; wacom->shared->touch_down = wacom_wac_finger_count_touches(wacom); + input_sync(touch_input); } }
- input_report_switch(touch_input, SW_MUTE_DEVICE, !(data[281] >> 7)); - input_sync(touch_input); + if (wacom->num_contacts_left == 0) { + // Be careful that we don't accidentally call input_sync with + // only a partial set of fingers of processed + input_report_switch(touch_input, SW_MUTE_DEVICE, !(data[281] >> 7)); + input_sync(touch_input); + } + }
static void wacom_intuos_pro2_bt_pad(struct wacom_wac *wacom)