root/drivers/hid/hid-semitek.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  HID driver for Semitek keyboards
 *
 *  Copyright (c) 2021 Benjamin Moody
 */

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

#include "hid-ids.h"

static const __u8 *semitek_report_fixup(struct hid_device *hdev, __u8 *rdesc,
                                        unsigned int *rsize)
{
        /* In the report descriptor for interface 2, fix the incorrect
           description of report ID 0x04 (the report contains a
           bitmask, not an array of keycodes.) */
        if (*rsize == 0xcb && rdesc[0x83] == 0x81 && rdesc[0x84] == 0x00) {
                hid_info(hdev, "fixing up Semitek report descriptor\n");
                rdesc[0x84] = 0x02;
        }
        return rdesc;
}

static const struct hid_device_id semitek_devices[] = {
        { HID_USB_DEVICE(USB_VENDOR_ID_SEMITEK, USB_DEVICE_ID_SEMITEK_KEYBOARD) },
        { }
};
MODULE_DEVICE_TABLE(hid, semitek_devices);

static struct hid_driver semitek_driver = {
        .name = "semitek",
        .id_table = semitek_devices,
        .report_fixup = semitek_report_fixup,
};
module_hid_driver(semitek_driver);

MODULE_DESCRIPTION("HID driver for Semitek keyboards");
MODULE_LICENSE("GPL");