HID: multitouch: add device ID for Apple Touch Bar

This patch adds the device ID of Apple Touch Bar found on x86 MacBook Pros
to the hid-multitouch driver.

Note that this is device ID is for T2 Macs. Testing on T1 Macs would be
appreciated.

Signed-off-by: Kerem Karabay <[email protected]>
Co-developed-by: Aditya Garg <[email protected]>
Signed-off-by: Aditya Garg <[email protected]>
Signed-off-by: Jiri Kosina <[email protected]>

Author: kekrby

drivers/hid/Kconfig

@@ -771,6 +771,7 @@ config HID_MULTITOUCH
 	  Say Y here if you have one of the following devices:
 	  - 3M PCT touch screens
 	  - ActionStar dual touch panels
+	  - Apple Touch Bar on x86 MacBook Pros
 	  - Atmel panels
 	  - Cando dual touch panels
 	  - Chunghwa panels

drivers/hid/hid-multitouch.c

@@ -221,6 +221,7 @@ static void mt_post_parse(struct mt_device *td, struct mt_application *app);
 #define MT_CLS_GOOGLE				0x0111
 #define MT_CLS_RAZER_BLADE_STEALTH		0x0112
 #define MT_CLS_SMART_TECH			0x0113
+#define MT_CLS_APPLE_TOUCHBAR			0x0114
 #define MT_CLS_SIS				0x0457
 
 #define MT_DEFAULT_MAXCONTACT	10
@@ -406,6 +407,12 @@ static const struct mt_class mt_classes[] = {
 			MT_QUIRK_CONTACT_CNT_ACCURATE |
 			MT_QUIRK_SEPARATE_APP_REPORT,
 	},
+	{ .name = MT_CLS_APPLE_TOUCHBAR,
+		.quirks = MT_QUIRK_HOVERING |
+			MT_QUIRK_SLOT_IS_CONTACTID_MINUS_ONE |
+			MT_QUIRK_APPLE_TOUCHBAR,
+		.maxcontacts = 11,
+	},
 	{ .name = MT_CLS_SIS,
 		.quirks = MT_QUIRK_NOT_SEEN_MEANS_UP |
 			MT_QUIRK_ALWAYS_VALID |
@@ -1858,6 +1865,11 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	if (ret != 0)
 		return ret;
 
+	if (mtclass->name == MT_CLS_APPLE_TOUCHBAR &&
+	    !hid_find_field(hdev, HID_INPUT_REPORT,
+			    HID_DG_TOUCHPAD, HID_DG_TRANSDUCER_INDEX))
+		return -ENODEV;
+
 	if (mtclass->quirks & MT_QUIRK_FIX_CONST_CONTACT_ID)
 		mt_fix_const_fields(hdev, HID_DG_CONTACTID);
 
@@ -2349,6 +2361,11 @@ static const struct hid_device_id mt_devices[] = {
 		MT_USB_DEVICE(USB_VENDOR_ID_XIROKU,
 			USB_DEVICE_ID_XIROKU_CSR2) },
 
+	/* Apple Touch Bar */
+	{ .driver_data = MT_CLS_APPLE_TOUCHBAR,
+		HID_USB_DEVICE(USB_VENDOR_ID_APPLE,
+			USB_DEVICE_ID_APPLE_TOUCHBAR_DISPLAY) },
+
 	/* Google MT devices */
 	{ .driver_data = MT_CLS_GOOGLE,
 		HID_DEVICE(HID_BUS_ANY, HID_GROUP_ANY, USB_VENDOR_ID_GOOGLE,