On Tue, May 7, 2019 at 8:53 PM Gerecke, Jason <killertofu@xxxxxxxxx> wrote:
>
> From: Jason Gerecke <jason.gerecke@xxxxxxxxx>
>
> 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@xxxxxxxxxxxxxxx> # 4.11+
> Signed-off-by: Jason Gerecke <jason.gerecke@xxxxxxxxx>
> ---
series applied to for-5.2/upstream-fixes
Cheers,
Benjamin
> 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)
> --
> 2.21.0
>
