Input: bcm5974 - add support for touchpads found in MacBookAir4,2

Added USB device IDs for MacBookAir4,2 trackpad. Device constants were
copied from the MacBookAir3,2 constants. The 4,2 device specification is
reportedly unchanged from the 3,2 predecessor and seems to work well.
Signed-off-by: Joshua V Dillon <jvdillon@gmail.com>
Signed-off-by: Chase Douglas <chase.douglas@canonical.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/mouse/bcm5974.c

@@ -67,6 +67,10 @@
 #define USB_DEVICE_ID_APPLE_WELLSPRING5_ANSI	0x0245
 #define USB_DEVICE_ID_APPLE_WELLSPRING5_ISO	0x0246
 #define USB_DEVICE_ID_APPLE_WELLSPRING5_JIS	0x0247
+/* MacbookAir4,2 (unibody, July 2011) */
+#define USB_DEVICE_ID_APPLE_WELLSPRING6_ANSI	0x024c
+#define USB_DEVICE_ID_APPLE_WELLSPRING6_ISO	0x024d
+#define USB_DEVICE_ID_APPLE_WELLSPRING6_JIS	0x024e
 
 #define BCM5974_DEVICE(prod) {					\
 	.match_flags = (USB_DEVICE_ID_MATCH_DEVICE |		\
@@ -104,6 +108,10 @@ static const struct usb_device_id bcm5974_table[] = {
 	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING5_ANSI),
 	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING5_ISO),
 	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING5_JIS),
+	/* MacbookAir4,2 */
+	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING6_ANSI),
+	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING6_ISO),
+	BCM5974_DEVICE(USB_DEVICE_ID_APPLE_WELLSPRING6_JIS),
 	/* Terminating entry */
 	{}
 };
@@ -294,6 +302,18 @@ static const struct bcm5974_config bcm5974_config_table[] = {
 		{ DIM_X, DIM_X / SN_COORD, -4415, 5050 },
 		{ DIM_Y, DIM_Y / SN_COORD, -55, 6680 }
 	},
+	{
+		USB_DEVICE_ID_APPLE_WELLSPRING6_ANSI,
+		USB_DEVICE_ID_APPLE_WELLSPRING6_ISO,
+		USB_DEVICE_ID_APPLE_WELLSPRING6_JIS,
+		HAS_INTEGRATED_BUTTON,
+		0x84, sizeof(struct bt_data),
+		0x81, TYPE2, FINGER_TYPE2, FINGER_TYPE2 + SIZEOF_ALL_FINGERS,
+		{ DIM_PRESSURE, DIM_PRESSURE / SN_PRESSURE, 0, 300 },
+		{ DIM_WIDTH, DIM_WIDTH / SN_WIDTH, 0, 2048 },
+		{ DIM_X, DIM_X / SN_COORD, -4620, 5140 },
+		{ DIM_Y, DIM_Y / SN_COORD, -150, 6600 }
+	},
 	{}
 };