evdev: always defuzz absolute touchscreens

If a touchscreen has a fuzz value use it for motion hysteresis similar to how
we do it for a touchpad. This stops pointer wobbles as seen in
https://bugs.freedesktop.org/show_bug.cgi?id=94918

It's up to the system to override or set the kernel's fuzz value correctly,
i.e. a udev hwdb entry is required where the kernel driver does not set it.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Jonas Ådahl <jadahl@gmail.com>

diff --git a/src/evdev.c b/src/evdev.c
index 4f69cb1eba0f4dc5badad8ec0a253dbb25de4264..bfa618067c48a02dad7f0aee0ae16b174fa9debc 100644 (file)
--- a/src/evdev.c
+++ b/src/evdev.c
@@ -342,6 +342,30 @@ evdev_post_trackpoint_scroll(struct evdev_device *device,
        return true;
 }
 
+static inline bool
+evdev_filter_defuzz_touch(struct evdev_device *device, struct mt_slot *slot)
+{
+       struct device_coords point;
+
+       if (!device->mt.want_hysteresis)
+               return false;
+
+       point.x = evdev_hysteresis(slot->point.x,
+                                  slot->hysteresis_center.x,
+                                  device->mt.hysteresis_margin.x);
+       point.y = evdev_hysteresis(slot->point.y,
+                                  slot->hysteresis_center.y,
+                                  device->mt.hysteresis_margin.y);
+
+       slot->hysteresis_center = slot->point;
+       if (point.x == slot->point.x && point.y == slot->point.y)
+               return true;
+
+       slot->point = point;
+
+       return false;
+}
+
 static void
 evdev_flush_pending_event(struct evdev_device *device, uint64_t time)
 {
@@ -414,6 +438,7 @@ evdev_flush_pending_event(struct evdev_device *device, uint64_t time)
 
                seat->slot_map |= 1 << seat_slot;
                point = slot->point;
+               slot->hysteresis_center = point;
                evdev_transform_absolute(device, &point);
 
                touch_notify_touch_down(base, time, slot_idx, seat_slot,
@@ -429,6 +454,9 @@ evdev_flush_pending_event(struct evdev_device *device, uint64_t time)
                if (seat_slot == -1)
                        break;
 
+               if (evdev_filter_defuzz_touch(device, slot))
+                       break;
+
                evdev_transform_absolute(device, &point);
                touch_notify_touch_motion(base, time, slot_idx, seat_slot,
                                          &point);
@@ -2015,6 +2043,12 @@ evdev_configure_mt_device(struct evdev_device *device)
        device->mt.slots_len = num_slots;
        device->mt.slot = active_slot;
 
+       if (device->abs.absinfo_x->fuzz || device->abs.absinfo_y->fuzz) {
+               device->mt.want_hysteresis = true;
+               device->mt.hysteresis_margin.x = device->abs.absinfo_x->fuzz/2;
+               device->mt.hysteresis_margin.y = device->abs.absinfo_y->fuzz/2;
+       }
+
        return 0;
 }
 

diff --git a/src/evdev.h b/src/evdev.h
index 4171c8a4b6d9ddb0448572aa7203b4d89d650542..1e38b5e6161f2a73bd8c5d86eeafc7e2fa7b50c3 100644 (file)
--- a/src/evdev.h
+++ b/src/evdev.h
@@ -120,6 +120,7 @@ enum evdev_device_model {
 struct mt_slot {
        int32_t seat_slot;
        struct device_coords point;
+       struct device_coords hysteresis_center;
 };
 
 struct evdev_device {
@@ -153,6 +154,8 @@ struct evdev_device {
                int slot;
                struct mt_slot *slots;
                size_t slots_len;
+               bool want_hysteresis;
+               struct device_coords hysteresis_margin;
        } mt;
        struct mtdev *mtdev;
 

diff --git a/test/Makefile.am b/test/Makefile.am
index d328c927afabd9b30c9b7b875eec49ce05743b8b..6ab36aac4630af712d0eb3a9dbae3775da426f9a 100644 (file)
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -44,6 +44,7 @@ liblitest_la_SOURCES = \
        litest-device-synaptics-x1-carbon-3rd.c \
        litest-device-trackpoint.c \
        litest-device-touch-screen.c \
+       litest-device-touchscreen-fuzz.c \
        litest-device-wacom-bamboo-tablet.c \
        litest-device-wacom-cintiq-tablet.c \
        litest-device-wacom-cintiq-24hd.c \

diff --git a/test/litest-device-touchscreen-fuzz.c b/test/litest-device-touchscreen-fuzz.c
new file mode 100644 (file)
index 0000000..6f374c5
--- /dev/null
+++ b/test/litest-device-touchscreen-fuzz.c
@@ -0,0 +1,96 @@
+/*
+ * Copyright © 2015 Canonical, Ltd.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "litest.h"
+#include "litest-int.h"
+
+static void litest_fuzz_mt_setup(void)
+{
+       struct litest_device *d =
+               litest_create_device(LITEST_MULTITOUCH_FUZZ_SCREEN);
+       litest_set_current_device(d);
+}
+
+static struct input_event down[] = {
+       { .type = EV_ABS, .code = ABS_MT_SLOT, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_ABS, .code = ABS_MT_TRACKING_ID, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_ABS, .code = ABS_MT_POSITION_X, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_ABS, .code = ABS_MT_POSITION_Y, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_ABS, .code = ABS_MT_PRESSURE, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_SYN, .code = SYN_REPORT, .value = 0 },
+       { .type = -1, .code = -1 },
+};
+
+static struct input_event move[] = {
+       { .type = EV_ABS, .code = ABS_MT_SLOT, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_ABS, .code = ABS_MT_POSITION_X, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_ABS, .code = ABS_MT_POSITION_Y, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_ABS, .code = ABS_MT_PRESSURE, .value = LITEST_AUTO_ASSIGN },
+       { .type = EV_SYN, .code = SYN_REPORT, .value = 0 },
+       { .type = -1, .code = -1 },
+};
+
+static struct litest_device_interface interface = {
+       .touch_down_events = down,
+       .touch_move_events = move,
+};
+
+static struct input_absinfo absinfo[] = {
+       { ABS_X, 0, 1500, 10, 0, 0 },
+       { ABS_Y, 0, 2500, 10, 0, 0 },
+       { ABS_MT_SLOT, 0, 9, 0, 0, 0 },
+       { ABS_MT_POSITION_X, 0, 1500, 10, 0, 0 },
+       { ABS_MT_POSITION_Y, 0, 2500, 10, 0, 0 },
+       { ABS_MT_PRESSURE, 0, 255, 0, 0, 0 },
+       { ABS_MT_TRACKING_ID, 0, 65535, 0, 0, 0 },
+       { .value = -1 },
+};
+
+static struct input_id input_id = {
+       .bustype = 0x1,
+       .vendor = 0x0,
+       .product = 0x25,
+};
+
+static int events[] = {
+       EV_KEY, BTN_TOUCH,
+       INPUT_PROP_MAX, INPUT_PROP_DIRECT,
+       -1, -1
+};
+
+struct litest_test_device litest_multitouch_fuzz_screen_device = {
+       .type = LITEST_MULTITOUCH_FUZZ_SCREEN,
+       .features = LITEST_TOUCH,
+       .shortname = "touchscreen-fuzz",
+       .setup = litest_fuzz_mt_setup,
+       .interface = &interface,
+
+       .name = "touchscreen with fuzz",
+       .id = &input_id,
+       .events = events,
+       .absinfo = absinfo,
+};

diff --git a/test/litest.c b/test/litest.c
index 67ff937509a95d57bfbdd0166422ac2c685e8e37..937e86772e8a9c3c3daf66135331b8eb0a059673 100644 (file)
--- a/test/litest.c
+++ b/test/litest.c
@@ -379,6 +379,7 @@ extern struct litest_test_device litest_cyborg_rat_device;
 extern struct litest_test_device litest_yubikey_device;
 extern struct litest_test_device litest_synaptics_i2c_device;
 extern struct litest_test_device litest_wacom_cintiq_24hd_device;
+extern struct litest_test_device litest_multitouch_fuzz_screen_device;
 
 struct litest_test_device* devices[] = {
        &litest_synaptics_clickpad_device,
@@ -424,6 +425,7 @@ struct litest_test_device* devices[] = {
        &litest_yubikey_device,
        &litest_synaptics_i2c_device,
        &litest_wacom_cintiq_24hd_device,
+       &litest_multitouch_fuzz_screen_device,
        NULL,
 };
 

diff --git a/test/litest.h b/test/litest.h
index c218361e097ff086ab4253eb70bbc89b882de8e4..cc06ca51777ba730bbeb1c4c70e4d54427871e34 100644 (file)
--- a/test/litest.h
+++ b/test/litest.h
@@ -196,6 +196,7 @@ enum litest_device_type {
        LITEST_YUBIKEY = -42,
        LITEST_SYNAPTICS_I2C = -43,
        LITEST_WACOM_CINTIQ_24HD = -44,
+       LITEST_MULTITOUCH_FUZZ_SCREEN = -45,
 };
 
 enum litest_device_feature {

diff --git a/test/touch.c b/test/touch.c
index a2a506b7210a3bc566d368ad0fce400482b7c521..cc1cfb27c840337380d88a4ff9f63a8739662d84 100644 (file)
--- a/test/touch.c
+++ b/test/touch.c
@@ -675,6 +675,50 @@ START_TEST(touch_time_usec)
 }
 END_TEST
 
+START_TEST(touch_fuzz)
+{
+       struct litest_device *dev = litest_current_device();
+       struct libinput *li = dev->libinput;
+       struct libinput_event *event;
+       int i;
+       int x = 700, y = 300;
+
+       litest_drain_events(dev->libinput);
+
+       litest_event(dev, EV_ABS, ABS_MT_TRACKING_ID, 30);
+       litest_event(dev, EV_ABS, ABS_MT_SLOT, 0);
+       litest_event(dev, EV_ABS, ABS_MT_POSITION_X, x);
+       litest_event(dev, EV_ABS, ABS_MT_POSITION_Y, y);
+       litest_event(dev, EV_KEY, BTN_TOUCH, 1);
+       litest_event(dev, EV_SYN, SYN_REPORT, 0);
+       libinput_dispatch(li);
+
+       event = libinput_get_event(li);
+       litest_is_touch_event(event, LIBINPUT_EVENT_TOUCH_DOWN);
+       libinput_event_destroy(event);
+       event = libinput_get_event(li);
+       litest_is_touch_event(event, LIBINPUT_EVENT_TOUCH_FRAME);
+       libinput_event_destroy(event);
+
+       litest_drain_events(li);
+
+       for (i = 0; i < 50; i++) {
+               if (i % 2) {
+                       x++;
+                       y--;
+               } else {
+                       x--;
+                       y++;
+               }
+               litest_event(dev, EV_ABS, ABS_MT_POSITION_X, x);
+               litest_event(dev, EV_ABS, ABS_MT_POSITION_Y, y);
+               litest_event(dev, EV_SYN, SYN_REPORT, 0);
+               libinput_dispatch(li);
+               litest_assert_empty_queue(li);
+       }
+}
+END_TEST
+
 void
 litest_setup_tests(void)
 {
@@ -703,4 +747,6 @@ litest_setup_tests(void)
        litest_add_ranged("touch:state", touch_initial_state, LITEST_TOUCH, LITEST_PROTOCOL_A, &axes);
 
        litest_add("touch:time", touch_time_usec, LITEST_TOUCH, LITEST_TOUCHPAD);
+
+       litest_add_for_device("touch:fuzz", touch_fuzz, LITEST_MULTITOUCH_FUZZ_SCREEN);
 }