[PATCH] HID: multitouch: fix Dell Precision 7550 and 7750 button type

[José Expósito]

The touchpad present in the Dell Precision 7550 and 7750 laptops
reports a HID_DG_BUTTONTYPE of type MT_BUTTONTYPE_CLICKPAD. However,
the device is not a clickpad, it is a touchpad with physical buttons.

In order to fix this issue, a quirk for the device was introduced in
libinput [1] [2] to disable the INPUT_PROP_BUTTONPAD property:

	[Precision 7x50 Touchpad]
	MatchBus=i2c
	MatchUdevType=touchpad
	MatchDMIModalias=dmi:*svnDellInc.:pnPrecision7?50*
	AttrInputPropDisable=INPUT_PROP_BUTTONPAD

However, because of the change introduced in 37ef4c19b4 ("Input: clear
BTN_RIGHT/MIDDLE on buttonpads") the BTN_RIGHT key bit is not mapped
anymore breaking the device right click button.

In order to fix the issue, create a quirk for the device forcing its
button type to touchpad regardless of the value reported by the
firmware.

[1] https://gitlab.freedesktop.org/libinput/libinput/-/merge_requests/481
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1868789

Fixes: 37ef4c19b4 ("Input: clear BTN_RIGHT/MIDDLE on buttonpads")
Signed-off-by: José Expósito <jose.exposito89@xxxxxxxxx>
---
 drivers/hid/hid-ids.h        |  3 +++
 drivers/hid/hid-multitouch.c | 20 ++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 78bd3ddda442..6cf7a5b6835b 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -287,6 +287,9 @@
 
 #define USB_VENDOR_ID_CIDC		0x1677
 
+#define USB_VENDOR_ID_CIRQUE_CORP		0x0488
+#define USB_DEVICE_ID_DELL_PRECISION_7X50	0x120A
+
 #define USB_VENDOR_ID_CJTOUCH		0x24b8
 #define USB_DEVICE_ID_CJTOUCH_MULTI_TOUCH_0020	0x0020
 #define USB_DEVICE_ID_CJTOUCH_MULTI_TOUCH_0040	0x0040
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 99eabfb4145b..f012cf8e0b8c 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -71,6 +71,7 @@ MODULE_LICENSE("GPL");
 #define MT_QUIRK_SEPARATE_APP_REPORT	BIT(19)
 #define MT_QUIRK_FORCE_MULTI_INPUT	BIT(20)
 #define MT_QUIRK_DISABLE_WAKEUP		BIT(21)
+#define MT_QUIRK_BUTTONTYPE_TOUCHPAD	BIT(22)
 
 #define MT_INPUTMODE_TOUCHSCREEN	0x02
 #define MT_INPUTMODE_TOUCHPAD		0x03
@@ -194,6 +195,7 @@ static void mt_post_parse(struct mt_device *td, struct mt_application *app);
 #define MT_CLS_WIN_8_FORCE_MULTI_INPUT		0x0015
 #define MT_CLS_WIN_8_DISABLE_WAKEUP		0x0016
 #define MT_CLS_WIN_8_NO_STICKY_FINGERS		0x0017
+#define MT_CLS_BUTTONTYPE_TOUCHPAD		0x0018
 
 /* vendor specific classes */
 #define MT_CLS_3M				0x0101
@@ -302,6 +304,15 @@ static const struct mt_class mt_classes[] = {
 			MT_QUIRK_CONTACT_CNT_ACCURATE |
 			MT_QUIRK_WIN8_PTP_BUTTONS,
 		.export_all_inputs = true },
+	{ .name = MT_CLS_BUTTONTYPE_TOUCHPAD,
+		.quirks = MT_QUIRK_ALWAYS_VALID |
+			MT_QUIRK_IGNORE_DUPLICATES |
+			MT_QUIRK_HOVERING |
+			MT_QUIRK_CONTACT_CNT_ACCURATE |
+			MT_QUIRK_STICKY_FINGERS |
+			MT_QUIRK_WIN8_PTP_BUTTONS |
+			MT_QUIRK_BUTTONTYPE_TOUCHPAD,
+		.export_all_inputs = true },
 
 	/*
 	 * vendor specific classes
@@ -1286,6 +1297,9 @@ static int mt_touch_input_configured(struct hid_device *hdev,
 	    (app->buttons_count == 1))
 		td->is_buttonpad = true;
 
+	if (app->quirks & MT_QUIRK_BUTTONTYPE_TOUCHPAD)
+		td->is_buttonpad = false;
+
 	if (td->is_buttonpad)
 		__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
 
@@ -1872,6 +1886,12 @@ static const struct hid_device_id mt_devices[] = {
 		MT_USB_DEVICE(USB_VENDOR_ID_CHUNGHWAT,
 			USB_DEVICE_ID_CHUNGHWAT_MULTITOUCH) },
 
+	/* Cirque Corp (Dell Precision 7550 and 7750 touchpad) */
+	{ .driver_data = MT_CLS_BUTTONTYPE_TOUCHPAD,
+		HID_DEVICE(BUS_I2C, HID_GROUP_MULTITOUCH_WIN_8,
+			USB_VENDOR_ID_CIRQUE_CORP,
+			USB_DEVICE_ID_DELL_PRECISION_7X50) },
+
 	/* CJTouch panels */
 	{ .driver_data = MT_CLS_NSMU,
 		MT_USB_DEVICE(USB_VENDOR_ID_CJTOUCH,
-- 
2.25.1