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

drivers/hid/hid-logitech-dj.h

+#ifndef __HID_LOGITECH_DJ_H
+#define __HID_LOGITECH_DJ_H
+
+/*
+ *  HID driver for Logitech Unifying receivers
+ *
+ *  Copyright (c) 2011 Logitech
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/kfifo.h>
+
+#define DJ_MAX_PAIRED_DEVICES			6
+#define DJ_MAX_NUMBER_NOTIFICATIONS		8
+
+#define DJREPORT_SHORT_LENGTH			15
+#define DJREPORT_LONG_LENGTH			32
+
+#define REPORT_ID_DJ_SHORT			0x20
+#define REPORT_ID_DJ_LONG			0x21
+
+#define REPORT_TYPE_RFREPORT_FIRST		0x01
+#define REPORT_TYPE_RFREPORT_LAST		0x1F
+
+/* Command Switch to DJ mode */
+#define REPORT_TYPE_CMD_SWITCH			0x80
+#define CMD_SWITCH_PARAM_DEVBITFIELD		0x00
+#define CMD_SWITCH_PARAM_TIMEOUT_SECONDS	0x01
+#define TIMEOUT_NO_KEEPALIVE			0x00
+
+/* Command to Get the list of Paired devices */
+#define REPORT_TYPE_CMD_GET_PAIRED_DEVICES	0x81
+
+/* Device Paired Notification */
+#define REPORT_TYPE_NOTIF_DEVICE_PAIRED		0x41
+#define SPFUNCTION_MORE_NOTIF_EXPECTED		0x01
+#define SPFUNCTION_DEVICE_LIST_EMPTY		0x02
+#define DEVICE_PAIRED_PARAM_SPFUNCTION		0x00
+#define DEVICE_PAIRED_PARAM_EQUAD_ID_LSB	0x01
+#define DEVICE_PAIRED_PARAM_EQUAD_ID_MSB	0x02
+#define DEVICE_PAIRED_RF_REPORT_TYPE		0x03
+
+/* Device Un-Paired Notification */
+#define REPORT_TYPE_NOTIF_DEVICE_UNPAIRED	0x40
+
+
+/* Connection Status Notification */
+#define REPORT_TYPE_NOTIF_CONNECTION_STATUS	0x42
+#define CONNECTION_STATUS_PARAM_STATUS		0x00
+#define STATUS_LINKLOSS				0x01
+
+/* Error Notification */
+#define REPORT_TYPE_NOTIF_ERROR			0x7F
+#define NOTIF_ERROR_PARAM_ETYPE			0x00
+#define ETYPE_KEEPALIVE_TIMEOUT			0x01
+
+/* supported DJ HID && RF report types */
+#define REPORT_TYPE_KEYBOARD			0x01
+#define REPORT_TYPE_MOUSE			0x02
+#define REPORT_TYPE_CONSUMER_CONTROL		0x03
+#define REPORT_TYPE_SYSTEM_CONTROL		0x04
+#define REPORT_TYPE_MEDIA_CENTER		0x08
+#define REPORT_TYPE_LEDS			0x0E
+
+/* RF Report types bitfield */
+#define STD_KEYBOARD				0x00000002
+#define STD_MOUSE				0x00000004
+#define MULTIMEDIA				0x00000008
+#define POWER_KEYS				0x00000010
+#define MEDIA_CENTER				0x00000100
+#define KBD_LEDS				0x00004000
+
+struct dj_report {
+	u8 report_id;
+	u8 device_index;
+	u8 report_type;
+	u8 report_params[DJREPORT_SHORT_LENGTH - 3];
+};
+
+struct dj_receiver_dev {
+	struct hid_device *hdev;
+	struct dj_device *paired_dj_devices[DJ_MAX_PAIRED_DEVICES];
+	struct work_struct work;
+	struct kfifo notif_fifo;
+	spinlock_t lock;
+};
+
+struct dj_device {
+	struct hid_device *hdev;
+	struct dj_receiver_dev *dj_receiver_dev;
+	u32 reports_supported;
+	u8 device_index;
+};
+
+/**
+ * is_dj_device - know if the given dj_device is not the receiver.
+ * @dj_dev: the dj device to test
+ *
+ * This macro tests if a struct dj_device pointer is a device created
+ * by the bus enumarator.
+ */
+#define is_dj_device(dj_dev) \
+	(&(dj_dev)->dj_receiver_dev->hdev->dev == (dj_dev)->hdev->dev.parent)
+
+#endif