HID: google: add google hammer HID driver

Add Google hammer HID driver. This driver allow us to control hammer
keyboard backlight and support future features.

Signed-off-by: Wei-Ning Huang <wnhuang@google.com>
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 43ddcdf..360c289 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -445,7 +445,10 @@
 #define USB_DEVICE_ID_GOODTOUCH_000f	0x000f
 
 #define USB_VENDOR_ID_GOOGLE		0x18d1
+#define USB_DEVICE_ID_GOOGLE_HAMMER	0x5022
 #define USB_DEVICE_ID_GOOGLE_TOUCH_ROSE	0x5028
+#define USB_DEVICE_ID_GOOGLE_STAFF	0x502b
+#define USB_DEVICE_ID_GOOGLE_WAND	0x502d
 
 #define USB_VENDOR_ID_GOTOP		0x08f2
 #define USB_DEVICE_ID_SUPER_Q2		0x007f