hid-a4tech.c

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/*
 *  HID driver for some a4tech "special" devices
 *
 *  Copyright (c) 1999 Andreas Gal
 *  Copyright (c) 2000-2005 Vojtech Pavlik <[email protected]>
 *  Copyright (c) 2005 Michael Haboustak <[email protected]> for Concept2, Inc
 *  Copyright (c) 2006-2007 Jiri Kosina
 *  Copyright (c) 2008 Jiri Slaby
 */

/*
 * 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.
 */

#include <linux/device.h>
#include <linux/input.h>
#include <linux/hid.h>
#include <linux/module.h>
#include <linux/slab.h>

#include "hid-ids.h"

#define A4_2WHEEL_MOUSE_HACK_7  0x01
#define A4_2WHEEL_MOUSE_HACK_B8 0x02

struct a4tech_sc {
    unsigned long quirks;
    unsigned int hw_wheel;
    __s32 delayed_value;
};

static int a4_input_mapped(struct hid_device *hdev, struct hid_input *hi,
        struct hid_field *field, struct hid_usage *usage,
        unsigned long **bit, int *max)
{
    struct a4tech_sc *a4 = hid_get_drvdata(hdev);

    if (usage->type == EV_REL && usage->code == REL_WHEEL)
        set_bit(REL_HWHEEL, *bit);

    if ((a4->quirks & A4_2WHEEL_MOUSE_HACK_7) && usage->hid == 0x00090007)
        return -1;

    return 0;
}

static int a4_event(struct hid_device *hdev, struct hid_field *field,
        struct hid_usage *usage, __s32 value)
{
    struct a4tech_sc *a4 = hid_get_drvdata(hdev);
    struct input_dev *input;

    if (!(hdev->claimed & HID_CLAIMED_INPUT) || !field->hidinput ||
            !usage->type)
        return 0;

    input = field->hidinput->input;

    if (a4->quirks & A4_2WHEEL_MOUSE_HACK_B8) {
        if (usage->type == EV_REL && usage->code == REL_WHEEL) {
            a4->delayed_value = value;
            return 1;
        }

        if (usage->hid == 0x000100b8) {
            input_event(input, EV_REL, value ? REL_HWHEEL :
                    REL_WHEEL, a4->delayed_value);
            return 1;
        }
    }

    if ((a4->quirks & A4_2WHEEL_MOUSE_HACK_7) && usage->hid == 0x00090007) {
        a4->hw_wheel = !!value;
        return 1;
    }

    if (usage->code == REL_WHEEL && a4->hw_wheel) {
        input_event(input, usage->type, REL_HWHEEL, value);
        return 1;
    }

    return 0;
}

static int a4_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
    struct a4tech_sc *a4;
    int ret;

    a4 = kzalloc(sizeof(*a4), GFP_KERNEL);
    if (a4 == NULL) {
        hid_err(hdev, "can't alloc device descriptor\n");
        ret = -ENOMEM;
        goto err_free;
    }

    a4->quirks = id->driver_data;

    hid_set_drvdata(hdev, a4);

    ret = hid_parse(hdev);
    if (ret) {
        hid_err(hdev, "parse failed\n");
        goto err_free;
    }

    ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
    if (ret) {
        hid_err(hdev, "hw start failed\n");
        goto err_free;
    }

    return 0;
err_free:
    kfree(a4);
    return ret;
}

static void a4_remove(struct hid_device *hdev)
{
    struct a4tech_sc *a4 = hid_get_drvdata(hdev);

    hid_hw_stop(hdev);
    kfree(a4);
}

static const struct hid_device_id a4_devices[] = {
    { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_WCP32PU),
        .driver_data = A4_2WHEEL_MOUSE_HACK_7 },
    { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_X5_005D),
        .driver_data = A4_2WHEEL_MOUSE_HACK_B8 },
    { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_RP_649),
        .driver_data = A4_2WHEEL_MOUSE_HACK_B8 },
    { }
};
MODULE_DEVICE_TABLE(hid, a4_devices);

static struct hid_driver a4_driver = {
    .name = "a4tech",
    .id_table = a4_devices,
    .input_mapped = a4_input_mapped,
    .event = a4_event,
    .probe = a4_probe,
    .remove = a4_remove,
};

static int __init a4_init(void)
{
    return hid_register_driver(&a4_driver);
}

static void __exit a4_exit(void)
{
    hid_unregister_driver(&a4_driver);
}

module_init(a4_init);
module_exit(a4_exit);
MODULE_LICENSE("GPL");