drivers/hid/hid-speedlink.c

   1 /*
   2  *  HID driver for Speedlink Vicious and Divine Cezanne (USB mouse).
   3  *  Fixes "jumpy" cursor and removes nonexistent keyboard LEDS from
   4  *  the HID descriptor.
   5  *
   6  *  Copyright (c) 2011, 2013 Stefan Kriwanek <dev@stefankriwanek.de>
   7  */
   8
   9 /*
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 2 of the License, or (at your option)
  13  * any later version.
  14  */
  15
  16 #include <linux/device.h>
  17 #include <linux/hid.h>
  18 #include <linux/module.h>
  19
  20 #include "hid-ids.h"
  21
  22 static const struct hid_device_id speedlink_devices[] = {
  23         { HID_USB_DEVICE(USB_VENDOR_ID_X_TENSIONS, USB_DEVICE_ID_SPEEDLINK_VAD_CEZANNE)},
  24         { }
  25 };
  26
  27 static int speedlink_input_mapping(struct hid_device *hdev,
  28                 struct hid_input *hi,
  29                 struct hid_field *field, struct hid_usage *usage,
  30                 unsigned long **bit, int *max)
  31 {
  32         /*
  33          * The Cezanne mouse has a second "keyboard" USB endpoint for it is
  34          * able to map keyboard events to the button presses.
  35          * It sends a standard keyboard report descriptor, though, whose
  36          * LEDs we ignore.
  37          */
  38         switch (usage->hid & HID_USAGE_PAGE) {
  39         case HID_UP_LED:
  40                 return -1;
  41         }
  42         return 0;
  43 }
  44
  45 static int speedlink_event(struct hid_device *hdev, struct hid_field *field,
  46                 struct hid_usage *usage, __s32 value)
  47 {
  48         /* No other conditions due to usage_table. */
  49
  50         /* This fixes the "jumpy" cursor occuring due to invalid events sent
  51          * by the device. Some devices only send them with value==+256, others
  52          * don't. However, catching abs(value)>=256 is restrictive enough not
  53          * to interfere with devices that were bug-free (has been tested).
  54          */
  55         if (abs(value) >= 256)
  56                 return 1;
  57         /* Drop useless distance 0 events (on button clicks etc.) as well */
  58         if (value == 0)
  59                 return 1;
  60
  61         return 0;
  62 }
  63
  64 MODULE_DEVICE_TABLE(hid, speedlink_devices);
  65
  66 static const struct hid_usage_id speedlink_grabbed_usages[] = {
  67         { HID_GD_X, EV_REL, 0 },
  68         { HID_GD_Y, EV_REL, 1 },
  69         { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
  70 };
  71
  72 static struct hid_driver speedlink_driver = {
  73         .name = "speedlink",
  74         .id_table = speedlink_devices,
  75         .usage_table = speedlink_grabbed_usages,
  76         .input_mapping = speedlink_input_mapping,
  77         .event = speedlink_event,
  78 };
  79 module_hid_driver(speedlink_driver);
  80
  81 MODULE_LICENSE("GPL");