tablet: support tablet devices without BTN_TOOL_PEN

Some devices like the UC Logic WP5540U has BTN_STYLUS but not BTN_TOOL_PEN.
While a kernel bug, let's just handle these correctly anyway.

https://bugs.freedesktop.org/show_bug.cgi?id=102570

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Yay-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>

meson.build

@@ -569,6 +569,7 @@ if get_option('tests')
 		'test/litest-device-trackpoint.c',
 		'test/litest-device-touch-screen.c',
 		'test/litest-device-touchscreen-fuzz.c',
+		'test/litest-device-uclogic-tablet.c',
 		'test/litest-device-wacom-bamboo-16fg-pen.c',
 		'test/litest-device-wacom-cintiq-12wx-pen.c',
 		'test/litest-device-wacom-cintiq-13hdt-finger.c',

src/evdev-tablet.c

@@ -1975,7 +1975,8 @@ tablet_reject_device(struct evdev_device *device)
 	    !libevdev_has_event_code(evdev, EV_ABS, ABS_Y))
 		goto out;
 
-	if (!libevdev_has_event_code(evdev, EV_KEY, BTN_TOOL_PEN))
+	if (!libevdev_has_event_code(evdev, EV_KEY, BTN_TOOL_PEN) &&
+	    !libevdev_has_event_code(evdev, EV_KEY, BTN_STYLUS))
 		goto out;
 
 	if (evdev_device_get_size(device, &w, &h) != 0)
@@ -1996,7 +1997,9 @@ static int
 tablet_init(struct tablet_dispatch *tablet,
 	    struct evdev_device *device)
 {
+	struct libevdev *evdev = device->evdev;
 	enum libinput_tablet_tool_axis axis;
+	bool want_proximity_quirk = false;
 	int rc;
 
 	tablet->base.dispatch_type = DISPATCH_TABLET;
@@ -2026,7 +2029,16 @@ tablet_init(struct tablet_dispatch *tablet,
 
 	tablet_set_status(tablet, TABLET_TOOL_OUT_OF_PROXIMITY);
 
-	if (device->model_flags & EVDEV_MODEL_TABLET_NO_PROXIMITY_OUT) {
+	if (!libevdev_has_event_code(evdev, EV_KEY, BTN_TOOL_PEN)) {
+		libevdev_enable_event_code(evdev, EV_KEY, BTN_TOOL_PEN, NULL);
+		want_proximity_quirk = true;
+		tablet->quirks.proximity_out_forced = true;
+	}
+
+	if (device->model_flags & EVDEV_MODEL_TABLET_NO_PROXIMITY_OUT)
+		want_proximity_quirk = true;
+
+	if (want_proximity_quirk) {
 		tablet->quirks.need_to_force_prox_out = true;
 		libinput_timer_init(&tablet->quirks.prox_out_timer,
 				    tablet_libinput_context(tablet),

test/litest-device-uclogic-tablet.c

@@ -0,0 +1,106 @@
+/*
+ * Copyright © 2017 Red Hat, Inc.
+ *
+ * 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.
+ */
+
+#include "config.h"
+
+#include "litest.h"
+#include "litest-int.h"
+
+static void litest_uclogic_tablet_setup(void)
+{
+	struct litest_device *d = litest_create_device(LITEST_UCLOGIC_TABLET);
+	litest_set_current_device(d);
+}
+
+static struct input_event proximity_in[] = {
+	{ .type = EV_ABS, .code = ABS_X, .value = LITEST_AUTO_ASSIGN },
+	{ .type = EV_ABS, .code = ABS_Y, .value = LITEST_AUTO_ASSIGN },
+	{ .type = EV_ABS, .code = ABS_PRESSURE, .value = LITEST_AUTO_ASSIGN },
+	{ .type = EV_SYN, .code = SYN_REPORT, .value = 0 },
+	{ .type = -1, .code = -1 },
+};
+
+static struct input_event proximity_out[] = {
+	{ .type = -1, .code = -1 },
+};
+
+static struct input_event motion[] = {
+	{ .type = EV_ABS, .code = ABS_X, .value = LITEST_AUTO_ASSIGN },
+	{ .type = EV_ABS, .code = ABS_Y, .value = LITEST_AUTO_ASSIGN },
+	{ .type = EV_ABS, .code = ABS_PRESSURE, .value = LITEST_AUTO_ASSIGN },
+	{ .type = EV_SYN, .code = SYN_REPORT, .value = 0 },
+	{ .type = -1, .code = -1 },
+};
+
+static int
+get_axis_default(struct litest_device *d, unsigned int evcode, int32_t *value)
+{
+	switch (evcode) {
+	case ABS_PRESSURE:
+		*value = 100;
+		return 0;
+	}
+	return 1;
+}
+
+static struct litest_device_interface interface = {
+	.tablet_proximity_in_events = proximity_in,
+	.tablet_proximity_out_events = proximity_out,
+	.tablet_motion_events = motion,
+
+	.get_axis_default = get_axis_default,
+};
+
+static struct input_absinfo absinfo[] = {
+	{ ABS_X, 0, 32767, 0, 0, 235 },
+	{ ABS_Y, 0, 32767, 0, 0, 323 },
+	{ ABS_PRESSURE, 0, 1023, 0, 0, 0 },
+	{ .value = -1 },
+};
+
+static struct input_id input_id = {
+	.bustype = 0x3,
+	.vendor = 0x256c,
+	.product = 0x6e,
+};
+
+static int events[] = {
+	EV_KEY, BTN_TOUCH,
+	EV_KEY, BTN_STYLUS,
+	EV_KEY, BTN_STYLUS2,
+	EV_MSC, MSC_SCAN,
+	-1, -1,
+};
+
+struct litest_test_device litest_uclogic_tablet_device = {
+	.type = LITEST_UCLOGIC_TABLET,
+	.features = LITEST_TABLET,
+	.shortname = "uclogic-tablet",
+	.setup = litest_uclogic_tablet_setup,
+	.interface = &interface,
+
+	.name = "uclogic PenTablet Pen",
+	.id = &input_id,
+	.events = events,
+	.absinfo = absinfo,
+};

test/litest.c

@@ -418,6 +418,7 @@ extern struct litest_test_device litest_gpio_keys_device;
 extern struct litest_test_device litest_ignored_mouse_device;
 extern struct litest_test_device litest_wacom_mobilestudio_13hdt_pad_device;
 extern struct litest_test_device litest_thinkpad_extrabuttons_device;
+extern struct litest_test_device litest_uclogic_tablet_device;
 
 struct litest_test_device* devices[] = {
 	&litest_synaptics_clickpad_device,
@@ -487,6 +488,7 @@ struct litest_test_device* devices[] = {
 	&litest_ignored_mouse_device,
 	&litest_wacom_mobilestudio_13hdt_pad_device,
 	&litest_thinkpad_extrabuttons_device,
+	&litest_uclogic_tablet_device,
 	NULL,
 };
 

test/litest.h

@@ -238,6 +238,7 @@ enum litest_device_type {
 	LITEST_IGNORED_MOUSE,
 	LITEST_WACOM_MOBILESTUDIO_PRO_16_PAD,
 	LITEST_THINKPAD_EXTRABUTTONS,
+	LITEST_UCLOGIC_TABLET,
 };
 
 enum litest_device_feature {

test/test-tablet.c

@@ -260,6 +260,8 @@ tablet_has_proxout_quirk(struct litest_device *dev)
 
 	has_quirk = !!udev_device_get_property_value(udev_device,
 			   "LIBINPUT_MODEL_TABLET_NO_PROXIMITY_OUT");
+	if (!has_quirk)
+		has_quirk = !libevdev_has_event_code(dev->evdev, EV_KEY, BTN_TOOL_PEN);
 
 	udev_device_unref(udev_device);