From 69dbdfffef20c715df9f381b2cee4e9e0a4efd93 Mon Sep 17 00:00:00 2001
From: Jason Gerecke <jason.gerecke@wacom.com>
Date: Tue, 7 May 2019 11:53:22 -0700
Subject: [PATCH] HID: wacom: Sync INTUOSP2_BT touch state after each frame if necessary
Git-commit: 69dbdfffef20c715df9f381b2cee4e9e0a4efd93
Patch-mainline: v5.2 or v5.2-rc5 (next release)
References: bsc#1051510
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: 4922cd26f03c ("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>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
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)
--
2.16.4