HID: add driver for the Logitech Flight System G940

Implements a new USB-HID for Force Feedback based on the normal
Logitech Force Feedback code and FF-Memless.

Currently only supports the FF_CONSTANT effect although the joystick
appears to support additional non-standard ones.

Signed-off-by: Gary Stein <LordCnidarian@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 5f73774..317049b 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -189,6 +189,14 @@
 	  Say Y here if you want to enable force feedback support for Logitech
 	  Rumblepad 2 devices.
 
+config LOGIG940_FF
+	bool "Logitech Flight System G940 force feedback support"
+	depends on HID_LOGITECH
+	select INPUT_FF_MEMLESS
+	help
+	  Say Y here if you want to enable force feedback support for Logitech
+	  Flight System G940 devices.
+
 config HID_MICROSOFT
 	tristate "Microsoft" if EMBEDDED
 	depends on USB_HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index f8dc5ba..ce6c8da 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -18,6 +18,9 @@
 ifdef CONFIG_LOGIRUMBLEPAD2_FF
 	hid-logitech-objs	+= hid-lg2ff.o
 endif
+ifdef CONFIG_LOGIG940_FF
+	hid-logitech-objs	+= hid-lg3ff.o
+endif
 
 obj-$(CONFIG_HID_3M_PCT)	+= hid-3m-pct.o
 obj-$(CONFIG_HID_A4TECH)	+= hid-a4tech.o
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index a4b496c..a0c0c49 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1323,6 +1323,7 @@
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_WINGMAN_F3D) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_WINGMAN_FFG ) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_FORCE3D_PRO) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_FLIGHT_SYSTEM_G940) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_MOMO_WHEEL) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_G25_WHEEL) },
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 07e056b..c7c9cbf 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -300,6 +300,7 @@
 #define USB_DEVICE_ID_LOGITECH_RUMBLEPAD2_2	0xc219
 #define USB_DEVICE_ID_LOGITECH_WINGMAN_F3D	0xc283
 #define USB_DEVICE_ID_LOGITECH_FORCE3D_PRO	0xc286
+#define USB_DEVICE_ID_LOGITECH_FLIGHT_SYSTEM_G940	0xc287
 #define USB_DEVICE_ID_LOGITECH_WHEEL	0xc294
 #define USB_DEVICE_ID_LOGITECH_WINGMAN_FFG	0xc293
 #define USB_DEVICE_ID_LOGITECH_MOMO_WHEEL	0xc295
diff --git a/drivers/hid/hid-lg.c b/drivers/hid/hid-lg.c
index 9fcd3d0..3677c90 100644
--- a/drivers/hid/hid-lg.c
+++ b/drivers/hid/hid-lg.c
@@ -34,6 +34,7 @@
 #define LG_FF			0x200
 #define LG_FF2			0x400
 #define LG_RDESC_REL_ABS	0x800
+#define LG_FF3			0x1000
 
 /*
  * Certain Logitech keyboards send in report #3 keys which are far
@@ -266,7 +267,7 @@
 		goto err_free;
 	}
 
-	if (quirks & (LG_FF | LG_FF2))
+	if (quirks & (LG_FF | LG_FF2 | LG_FF3))
 		connect_mask &= ~HID_CONNECT_FF;
 
 	ret = hid_hw_start(hdev, connect_mask);
@@ -279,6 +280,8 @@
 		lgff_init(hdev);
 	if (quirks & LG_FF2)
 		lg2ff_init(hdev);
+	if (quirks & LG_FF3)
+		lg3ff_init(hdev);
 
 	return 0;
 err_free:
@@ -331,6 +334,8 @@
 		.driver_data = LG_FF },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_RUMBLEPAD2),
 		.driver_data = LG_FF2 },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_FLIGHT_SYSTEM_G940),
+		.driver_data = LG_FF3 },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_SPACENAVIGATOR),
 		.driver_data = LG_RDESC_REL_ABS },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_SPACETRAVELLER),
diff --git a/drivers/hid/hid-lg.h b/drivers/hid/hid-lg.h
index 27ae750..8069c3e 100644
--- a/drivers/hid/hid-lg.h
+++ b/drivers/hid/hid-lg.h
@@ -15,4 +15,10 @@
 static inline int lg2ff_init(struct hid_device *hdev) { return -1; }
 #endif
 
+#ifdef CONFIG_LOGIG940_FF
+int lg3ff_init(struct hid_device *hdev);
+#else
+static inline int lg3ff_init(struct hid_device *hdev) { return -1; }
+#endif
+
 #endif
diff --git a/drivers/hid/hid-lg3ff.c b/drivers/hid/hid-lg3ff.c
new file mode 100644
index 0000000..4002832
--- /dev/null
+++ b/drivers/hid/hid-lg3ff.c
@@ -0,0 +1,176 @@
+/*
+ *  Force feedback support for Logitech Flight System G940
+ *
+ *  Copyright (c) 2009 Gary Stein <LordCnidarian@gmail.com>
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/input.h>
+#include <linux/usb.h>
+#include <linux/hid.h>
+
+#include "usbhid/usbhid.h"
+#include "hid-lg.h"
+
+/*
+ * G940 Theory of Operation (from experimentation)
+ *
+ * There are 63 fields (only 3 of them currently used)
+ * 0 - seems to be command field
+ * 1 - 30 deal with the x axis
+ * 31 -60 deal with the y axis
+ *
+ * Field 1 is x axis constant force
+ * Field 31 is y axis constant force
+ *
+ * other interesting fields 1,2,3,4 on x axis
+ * (same for 31,32,33,34 on y axis)
+ *
+ * 0 0 127 127 makes the joystick autocenter hard
+ *
+ * 127 0 127 127 makes the joystick loose on the right,
+ * but stops all movemnt left
+ *
+ * -127 0 -127 -127 makes the joystick loose on the left,
+ * but stops all movement right
+ *
+ * 0 0 -127 -127 makes the joystick rattle very hard
+ *
+ * I'm sure these are effects that I don't know enough about them
+ */
+
+struct lg3ff_device {
+	struct hid_report *report;
+};
+
+static int hid_lg3ff_play(struct input_dev *dev, void *data,
+			 struct ff_effect *effect)
+{
+	struct hid_device *hid = input_get_drvdata(dev);
+	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+	int x, y;
+
+/*
+ * Maxusage should always be 63 (maximum fields)
+ * likely a better way to ensure this data is clean
+ */
+	memset(report->field[0]->value, 0, sizeof(__s32)*report->field[0]->maxusage);
+
+	switch (effect->type) {
+	case FF_CONSTANT:
+/*
+ * Already clamped in ff_memless
+ * 0 is center (different then other logitech)
+ */
+		x = effect->u.ramp.start_level;
+		y = effect->u.ramp.end_level;
+
+		/* send command byte */
+		report->field[0]->value[0] = 0x51;
+
+/*
+ * Sign backwards from other Force3d pro
+ * which get recast here in two's complement 8 bits
+ */
+		report->field[0]->value[1] = (unsigned char)(-x);
+		report->field[0]->value[31] = (unsigned char)(-y);
+
+		usbhid_submit_report(hid, report, USB_DIR_OUT);
+		break;
+	}
+	return 0;
+}
+static void hid_lg3ff_set_autocenter(struct input_dev *dev, u16 magnitude)
+{
+	struct hid_device *hid = input_get_drvdata(dev);
+	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+
+/*
+ * Auto Centering probed from device
+ * NOTE: deadman's switch on G940 must be covered
+ * for effects to work
+ */
+	report->field[0]->value[0] = 0x51;
+	report->field[0]->value[1] = 0x00;
+	report->field[0]->value[2] = 0x00;
+	report->field[0]->value[3] = 0x7F;
+	report->field[0]->value[4] = 0x7F;
+	report->field[0]->value[31] = 0x00;
+	report->field[0]->value[32] = 0x00;
+	report->field[0]->value[33] = 0x7F;
+	report->field[0]->value[34] = 0x7F;
+
+	usbhid_submit_report(hid, report, USB_DIR_OUT);
+}
+
+
+static const signed short ff3_joystick_ac[] = {
+	FF_CONSTANT,
+	FF_AUTOCENTER,
+	-1
+};
+
+int lg3ff_init(struct hid_device *hid)
+{
+	struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+	struct input_dev *dev = hidinput->input;
+	struct hid_report *report;
+	struct hid_field *field;
+	const signed short *ff_bits = ff3_joystick_ac;
+	int error;
+	int i;
+
+	/* Find the report to use */
+	if (list_empty(report_list)) {
+		err_hid("No output report found");
+		return -1;
+	}
+
+	/* Check that the report looks ok */
+	report = list_entry(report_list->next, struct hid_report, list);
+	if (!report) {
+		err_hid("NULL output report");
+		return -1;
+	}
+
+	field = report->field[0];
+	if (!field) {
+		err_hid("NULL field");
+		return -1;
+	}
+
+	/* Assume single fixed device G940 */
+	for (i = 0; ff_bits[i] >= 0; i++)
+		set_bit(ff_bits[i], dev->ffbit);
+
+	error = input_ff_create_memless(dev, NULL, hid_lg3ff_play);
+	if (error)
+		return error;
+
+	if (test_bit(FF_AUTOCENTER, dev->ffbit))
+		dev->ff->set_autocenter = hid_lg3ff_set_autocenter;
+
+	dev_info(&hid->dev, "Force feedback for Logitech Flight System G940 by "
+			"Gary Stein <LordCnidarian@gmail.com>\n");
+	return 0;
+}
+
diff --git a/drivers/hid/hid-lgff.c b/drivers/hid/hid-lgff.c
index 987abeb..61142b7 100644
--- a/drivers/hid/hid-lgff.c
+++ b/drivers/hid/hid-lgff.c
@@ -67,6 +67,7 @@
 	{ 0x046d, 0xc219, ff_rumble },
 	{ 0x046d, 0xc283, ff_joystick },
 	{ 0x046d, 0xc286, ff_joystick_ac },
+	{ 0x046d, 0xc287, ff_joystick_ac },
 	{ 0x046d, 0xc293, ff_joystick },
 	{ 0x046d, 0xc294, ff_wheel },
 	{ 0x046d, 0xc295, ff_joystick },