/*
 * Force feedback support for various HID compliant devices by ThrustMaster:
 *    ThrustMaster FireStorm Dual Power 2
 * and possibly others whose device ids haven't been added.
 *
 *  Modified to support ThrustMaster devices by Zinx Verituse
 *  on 2003-01-25 from the Logitech force feedback driver,
 *  which is by Johann Deneux.
 *
 *  Copyright (c) 2003 Zinx Verituse <zinx@epicsol.org>
 *  Copyright (c) 2002 Johann Deneux
 */

/*
 * 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/hid.h>
#include <linux/input.h>
#include <linux/usb.h>

#include "hid-ids.h"

static const signed short ff_rumble[] = {
        FF_RUMBLE,
        -1
};

static const signed short ff_joystick[] = {
        FF_CONSTANT,
        -1
};

#ifdef CONFIG_THRUSTMASTER_FF
#include "usbhid/usbhid.h"

/* Usages for thrustmaster devices I know about */
#define THRUSTMASTER_USAGE_FF   (HID_UP_GENDESK | 0xbb)

struct tmff_device {
        struct hid_report *report;
        struct hid_field *ff_field;
};

/* Changes values from 0 to 0xffff into values from minimum to maximum */
static inline int tmff_scale_u16(unsigned int in, int minimum, int maximum)
{
        int ret;

        ret = (in * (maximum - minimum) / 0xffff) + minimum;
        if (ret < minimum)
                return minimum;
        if (ret > maximum)
                return maximum;
        return ret;
}

/* Changes values from -0x80 to 0x7f into values from minimum to maximum */
static inline int tmff_scale_s8(int in, int minimum, int maximum)
{
        int ret;

        ret = (((in + 0x80) * (maximum - minimum)) / 0xff) + minimum;
        if (ret < minimum)
                return minimum;
        if (ret > maximum)
                return maximum;
        return ret;
}

static int tmff_play(struct input_dev *dev, void *data,
                struct ff_effect *effect)
{
        struct hid_device *hid = input_get_drvdata(dev);
        struct tmff_device *tmff = data;
        struct hid_field *ff_field = tmff->ff_field;
        int x, y;
        int left, right;        /* Rumbling */

        switch (effect->type) {
        case FF_CONSTANT:
                x = tmff_scale_s8(effect->u.ramp.start_level,
                                        ff_field->logical_minimum,
                                        ff_field->logical_maximum);
                y = tmff_scale_s8(effect->u.ramp.end_level,
                                        ff_field->logical_minimum,
                                        ff_field->logical_maximum);

                dbg_hid("(x, y)=(%04x, %04x)\n", x, y);
                ff_field->value[0] = x;
                ff_field->value[1] = y;
                usbhid_submit_report(hid, tmff->report, USB_DIR_OUT);
                break;

        case FF_RUMBLE:
                left = tmff_scale_u16(effect->u.rumble.weak_magnitude,
                                        ff_field->logical_minimum,
                                        ff_field->logical_maximum);
                right = tmff_scale_u16(effect->u.rumble.strong_magnitude,
                                        ff_field->logical_minimum,
                                        ff_field->logical_maximum);

                dbg_hid("(left,right)=(%08x, %08x)\n", left, right);
                ff_field->value[0] = left;
                ff_field->value[1] = right;
                usbhid_submit_report(hid, tmff->report, USB_DIR_OUT);
                break;
        }
        return 0;
}

static int tmff_init(struct hid_device *hid, const signed short *ff_bits)
{
        struct tmff_device *tmff;
        struct hid_report *report;
        struct list_head *report_list;
        struct hid_input *hidinput = list_entry(hid->inputs.next,
                                                        struct hid_input, list);
        struct input_dev *input_dev = hidinput->input;
        int error;
        int i;

        tmff = kzalloc(sizeof(struct tmff_device), GFP_KERNEL);
        if (!tmff)
                return -ENOMEM;

        /* Find the report to use */
        report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
        list_for_each_entry(report, report_list, list) {
                int fieldnum;

                for (fieldnum = 0; fieldnum < report->maxfield; ++fieldnum) {
                        struct hid_field *field = report->field[fieldnum];

                        if (field->maxusage <= 0)
                                continue;

                        switch (field->usage[0].hid) {
                        case THRUSTMASTER_USAGE_FF:
                                if (field->report_count < 2) {
                                        dev_warn(&hid->dev, "ignoring FF field "
                                                "with report_count < 2\n");
                                        continue;
                                }

                                if (field->logical_maximum ==
                                                field->logical_minimum) {
                                        dev_warn(&hid->dev, "ignoring FF field "
                                                        "with logical_maximum "
                                                        "== logical_minimum\n");
                                        continue;
                                }

                                if (tmff->report && tmff->report != report) {
                                        dev_warn(&hid->dev, "ignoring FF field "
                                                        "in other report\n");
                                        continue;
                                }

                                if (tmff->ff_field && tmff->ff_field != field) {
                                        dev_warn(&hid->dev, "ignoring "
                                                        "duplicate FF field\n");
                                        continue;
                                }

                                tmff->report = report;
                                tmff->ff_field = field;

                                for (i = 0; ff_bits[i] >= 0; i++)
                                        set_bit(ff_bits[i], input_dev->ffbit);

                                break;

                        default:
                                dev_warn(&hid->dev, "ignoring unknown output "
                                                "usage %08x\n",
                                                field->usage[0].hid);
                                continue;
                        }
                }
        }

        if (!tmff->report) {
                dev_err(&hid->dev, "can't find FF field in output reports\n");
                error = -ENODEV;
                goto fail;
        }

        error = input_ff_create_memless(input_dev, tmff, tmff_play);
        if (error)
                goto fail;

        dev_info(&hid->dev, "force feedback for ThrustMaster devices by Zinx "
                        "Verituse <zinx@epicsol.org>");
        return 0;

fail:
        kfree(tmff);
        return error;
}
#else
static inline int tmff_init(struct hid_device *hid, const signed short *ff_bits)
{
        return 0;
}
#endif

static int tm_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
        int ret;

        ret = hid_parse(hdev);
        if (ret) {
                dev_err(&hdev->dev, "parse failed\n");
                goto err;
        }

        ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
        if (ret) {
                dev_err(&hdev->dev, "hw start failed\n");
                goto err;
        }

        tmff_init(hdev, (void *)id->driver_data);

        return 0;
err:
        return ret;
}

static const struct hid_device_id tm_devices[] = {
        { HID_USB_DEVICE(USB_VENDOR_ID_THRUSTMASTER, 0xb300),
                .driver_data = (unsigned long)ff_rumble },
        { HID_USB_DEVICE(USB_VENDOR_ID_THRUSTMASTER, 0xb304),   /* FireStorm Dual Power 2 (and 3) */
                .driver_data = (unsigned long)ff_rumble },
        { HID_USB_DEVICE(USB_VENDOR_ID_THRUSTMASTER, 0xb323),   /* Dual Trigger 3-in-1 (PC Mode) */
                .driver_data = (unsigned long)ff_rumble },
        { HID_USB_DEVICE(USB_VENDOR_ID_THRUSTMASTER, 0xb324),   /* Dual Trigger 3-in-1 (PS3 Mode) */
                .driver_data = (unsigned long)ff_rumble },
        { HID_USB_DEVICE(USB_VENDOR_ID_THRUSTMASTER, 0xb651),   /* FGT Rumble Force Wheel */
                .driver_data = (unsigned long)ff_rumble },
        { HID_USB_DEVICE(USB_VENDOR_ID_THRUSTMASTER, 0xb654),   /* FGT Force Feedback Wheel */
                .driver_data = (unsigned long)ff_joystick },
        { }
};
MODULE_DEVICE_TABLE(hid, tm_devices);

static struct hid_driver tm_driver = {
        .name = "thrustmaster",
        .id_table = tm_devices,
        .probe = tm_probe,
};

static int __init tm_init(void)
{
        return hid_register_driver(&tm_driver);
}

static void __exit tm_exit(void)
{
        hid_unregister_driver(&tm_driver);
}

module_init(tm_init);
module_exit(tm_exit);
MODULE_LICENSE("GPL");