HID: Add full support for Logitech Unifying receivers

With this driver, all the devices paired to a single Unifying
receiver are exposed to user processes in separated /input/dev
nodes.

Keyboards with different layouts can be treated differently,
Multiplayer games on single PC (like home theater PC) can
differentiate input coming from different kbds paired to the
same receiver.

Up to now, when Logitech Unifying receivers are connected to a
Linux based system, a single keyboard and a single mouse are
presented to the HID Layer, even if the Unifying receiver can
pair up to six compatible devices. The Unifying receiver by default
multiplexes all incoming events (from multiple keyboards/mice)
into these two.

Signed-off-by: Nestor Lopez Casado <nlopezcasad@logitech.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/Kconfig

@@ -245,6 +245,15 @@ config HID_LOGITECH
 	---help---
 	Support for Logitech devices that are not fully compliant with HID standard.
 
+config HID_LOGITECH_DJ
+	tristate "Logitech Unifying receivers full support"
+	depends on HID_LOGITECH
+	default m
+	---help---
+	Say Y if you want support for Logitech Unifying receivers and devices.
+	Unifying receivers are capable of pairing up to 6 Logitech compliant
+	devices to the same receiver.
+
 config LOGITECH_FF
 	bool "Logitech force feedback support"
 	depends on HID_LOGITECH

drivers/hid/Makefile

@@ -43,6 +43,7 @@ obj-$(CONFIG_HID_KEYTOUCH)	+= hid-keytouch.o
 obj-$(CONFIG_HID_KYE)		+= hid-kye.o
 obj-$(CONFIG_HID_LCPOWER)       += hid-lcpower.o
 obj-$(CONFIG_HID_LOGITECH)	+= hid-logitech.o
+obj-$(CONFIG_HID_LOGITECH_DJ)	+= hid-logitech-dj.o
 obj-$(CONFIG_HID_MAGICMOUSE)    += hid-magicmouse.o
 obj-$(CONFIG_HID_MICROSOFT)	+= hid-microsoft.o
 obj-$(CONFIG_HID_MONTEREY)	+= hid-monterey.o

drivers/hid/hid-core.c

@@ -1419,6 +1419,8 @@ static const struct hid_device_id hid_have_special_driver[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_DFP_WHEEL) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_G25_WHEEL) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_G27_WHEEL) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_UNIFYING_RECEIVER) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_UNIFYING_RECEIVER_2) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_WII_WHEEL) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_RUMBLEPAD2) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_SPACETRAVELLER) },

drivers/hid/hid-ids.h

@@ -444,6 +444,8 @@
 #define USB_DEVICE_ID_S510_RECEIVER_2	0xc517
 #define USB_DEVICE_ID_LOGITECH_CORDLESS_DESKTOP_LX500	0xc512
 #define USB_DEVICE_ID_MX3000_RECEIVER	0xc513
+#define USB_DEVICE_ID_LOGITECH_UNIFYING_RECEIVER	0xc52b
+#define USB_DEVICE_ID_LOGITECH_UNIFYING_RECEIVER_2	0xc532
 #define USB_DEVICE_ID_SPACETRAVELLER	0xc623
 #define USB_DEVICE_ID_SPACENAVIGATOR	0xc626
 #define USB_DEVICE_ID_DINOVO_DESKTOP	0xc704