hid: force feedback driver for PantherLord USB/PS2 2in1 Adapter

Add a force feedback driver for PantherLord USB/PS2 2in1 Adapter,
0810:0001. The device identifies itself as "Twin USB Joystick".

Signed-off-by: Anssi Hannula <[e-mail]>
Signed-off-by: Jiri Kosina <[e-mail]>

drivers/usb/input/Kconfig

···
 	  Note: if you say N here, this device will still be supported, but without
 	  force feedback.
 
+config PANTHERLORD_FF
+	bool "PantherLord USB/PS2 2in1 Adapter support"
+	depends on HID_FF
+	select INPUT_FF_MEMLESS if USB_HID
+	help
+	  Say Y here if you have a PantherLord USB/PS2 2in1 Adapter and want
+	  to enable force feedback support for it.
+
 config THRUSTMASTER_FF
 	bool "ThrustMaster FireStorm Dual Power 2 support (EXPERIMENTAL)"
 	depends on HID_FF && EXPERIMENTAL

drivers/usb/input/Makefile

···
 ifeq ($(CONFIG_LOGITECH_FF),y)
 	usbhid-objs	+= hid-lgff.o
 endif
+ifeq ($(CONFIG_PANTHERLORD_FF),y)
+	usbhid-objs	+= hid-plff.o
+endif
 ifeq ($(CONFIG_THRUSTMASTER_FF),y)
 	usbhid-objs	+= hid-tmff.o
 endif

drivers/usb/input/hid-ff.c

···
 	{ 0x46d, 0xc295, hid_lgff_init }, /* Logitech MOMO force wheel */
 	{ 0x46d, 0xc219, hid_lgff_init }, /* Logitech Cordless rumble pad 2 */
 #endif
+#ifdef CONFIG_PANTHERLORD_FF
+	{ 0x810, 0x0001, hid_plff_init },
+#endif
 #ifdef CONFIG_THRUSTMASTER_FF
 	{ 0x44f, 0xb304, hid_tmff_init },
 #endif

drivers/usb/input/hid-plff.c

···
+/*
+ *  Force feedback support for PantherLord USB/PS2 2in1 Adapter devices
+ *
+ *  Copyright (c) 2007 Anssi Hannula <[e-mail]>
+ */
+
+/*
+ * 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
+ */
+
+
+/* #define DEBUG */
+
+#define debug(format, arg...) pr_debug("hid-plff: " format "\n" , ## arg)
+
+#include <linux/input.h>
+#include <linux/usb.h>
+#include <linux/hid.h>
+#include "usbhid.h"
+
+struct plff_device {
+	struct hid_report *report;
+};
+
+static int hid_plff_play(struct input_dev *dev, void *data,
+			 struct ff_effect *effect)
+{
+	struct hid_device *hid = dev->private;
+	struct plff_device *plff = data;
+	int left, right;
+
+	left = effect->u.rumble.strong_magnitude;
+	right = effect->u.rumble.weak_magnitude;
+	debug("called with 0x%04x 0x%04x", left, right);
+
+	left = left * 0x7f / 0xffff;
+	right = right * 0x7f / 0xffff;
+
+	plff->report->field[0]->value[2] = left;
+	plff->report->field[0]->value[3] = right;
+	debug("running with 0x%02x 0x%02x", left, right);
+	usbhid_submit_report(hid, plff->report, USB_DIR_OUT);
+
+	return 0;
+}
+
+int hid_plff_init(struct hid_device *hid)
+{
+	struct plff_device *plff;
+	struct hid_report *report;
+	struct hid_input *hidinput;
+	struct list_head *report_list =
+			&hid->report_enum[HID_OUTPUT_REPORT].report_list;
+	struct list_head *report_ptr = report_list;
+	struct input_dev *dev;
+	int error;
+
+	/* The device contains 2 output reports (one for each
+	   HID_QUIRK_MULTI_INPUT device), both containing 1 field, which
+	   contains 4 ff00.0002 usages and 4 16bit absolute values.
+
+	   The 2 input reports also contain a field which contains
+	   8 ff00.0001 usages and 8 boolean values. Their meaning is
+	   currently unknown. */
+
+	if (list_empty(report_list)) {
+		printk(KERN_ERR "hid-plff: no output reports found\n");
+		return -ENODEV;
+	}
+
+	list_for_each_entry(hidinput, &hid->inputs, list) {
+
+		report_ptr = report_ptr->next;
+
+		if (report_ptr == report_list) {
+			printk(KERN_ERR "hid-plff: required output report is missing\n");
+			return -ENODEV;
+		}
+
+		report = list_entry(report_ptr, struct hid_report, list);
+		if (report->maxfield < 1) {
+			printk(KERN_ERR "hid-plff: no fields in the report\n");
+			return -ENODEV;
+		}
+
+		if (report->field[0]->report_count < 4) {
+			printk(KERN_ERR "hid-plff: not enough values in the field\n");
+			return -ENODEV;
+		}
+
+		plff = kzalloc(sizeof(struct plff_device), GFP_KERNEL);
+		if (!plff)
+			return -ENOMEM;
+
+		dev = hidinput->input;
+
+		set_bit(FF_RUMBLE, dev->ffbit);
+
+		error = input_ff_create_memless(dev, plff, hid_plff_play);
+		if (error) {
+			kfree(plff);
+			return error;
+		}
+
+		plff->report = report;
+		plff->report->field[0]->value[0] = 0x00;
+		plff->report->field[0]->value[1] = 0x00;
+		plff->report->field[0]->value[2] = 0x00;
+		plff->report->field[0]->value[3] = 0x00;
+		usbhid_submit_report(hid, plff->report, USB_DIR_OUT);
+	}
+
+	printk(KERN_INFO "hid-plff: Force feedback for PantherLord USB/PS2 "
+	       "2in1 Adapters by Anssi Hannula <[e-mail]>\n");
+
+	return 0;
+}

include/linux/hid.h

···
 int hid_ff_init(struct hid_device *hid);
 
 int hid_lgff_init(struct hid_device *hid);
+int hid_plff_init(struct hid_device *hid);
 int hid_tmff_init(struct hid_device *hid);
 int hid_zpff_init(struct hid_device *hid);
 #ifdef CONFIG_HID_PID