drivers/hid/hid-elecom.c

   1 /*
   2  *  HID driver for ELECOM devices.
   3  *  Copyright (c) 2010 Richard Nauber <Richard.Nauber@gmail.com>
   4  *  Copyright (c) 2016 Yuxuan Shui <yshuiv7@gmail.com>
   5  *  Copyright (c) 2017 Diego Elio Pettenò <flameeyes@flameeyes.eu>
   6  */
   7
   8 /*
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by the Free
  11  * Software Foundation; either version 2 of the License, or (at your option)
  12  * any later version.
  13  */
  14
  15 #include <linux/device.h>
  16 #include <linux/hid.h>
  17 #include <linux/module.h>
  18
  19 #include "hid-ids.h"
  20
  21 static __u8 *elecom_report_fixup(struct hid_device *hdev, __u8 *rdesc,
  22                 unsigned int *rsize)
  23 {
  24         switch (hdev->product) {
  25         case USB_DEVICE_ID_ELECOM_BM084:
  26                 /* The BM084 Bluetooth mouse includes a non-existing horizontal
  27                  * wheel in the HID descriptor. */
  28                 if (*rsize >= 48 && rdesc[46] == 0x05 && rdesc[47] == 0x0c) {
  29                         hid_info(hdev, "Fixing up Elecom BM084 report descriptor\n");
  30                         rdesc[47] = 0x00;
  31                 }
  32                 break;
  33         case USB_DEVICE_ID_ELECOM_DEFT_WIRED:
  34         case USB_DEVICE_ID_ELECOM_DEFT_WIRELESS:
  35                 /* The DEFT trackball has eight buttons, but its descriptor only
  36                  * reports five, disabling the three Fn buttons on the top of
  37                  * the mouse.
  38                  *
  39                  * Apply the following diff to the descriptor:
  40                  *
  41                  * Collection (Physical),              Collection (Physical),
  42                  *     Report ID (1),                      Report ID (1),
  43                  *     Report Count (5),           ->      Report Count (8),
  44                  *     Report Size (1),                    Report Size (1),
  45                  *     Usage Page (Button),                Usage Page (Button),
  46                  *     Usage Minimum (01h),                Usage Minimum (01h),
  47                  *     Usage Maximum (05h),        ->      Usage Maximum (08h),
  48                  *     Logical Minimum (0),                Logical Minimum (0),
  49                  *     Logical Maximum (1),                Logical Maximum (1),
  50                  *     Input (Variable),                   Input (Variable),
  51                  *     Report Count (1),           ->      Report Count (0),
  52                  *     Report Size (3),                    Report Size (3),
  53                  *     Input (Constant),                   Input (Constant),
  54                  *     Report Size (16),                   Report Size (16),
  55                  *     Report Count (2),                   Report Count (2),
  56                  *     Usage Page (Desktop),               Usage Page (Desktop),
  57                  *     Usage (X),                          Usage (X),
  58                  *     Usage (Y),                          Usage (Y),
  59                  *     Logical Minimum (-32768),           Logical Minimum (-32768),
  60                  *     Logical Maximum (32767),            Logical Maximum (32767),
  61                  *     Input (Variable, Relative),         Input (Variable, Relative),
  62                  * End Collection,                     End Collection,
  63                  */
  64                 if (*rsize == 213 && rdesc[13] == 5 && rdesc[21] == 5) {
  65                         hid_info(hdev, "Fixing up Elecom DEFT Fn buttons\n");
  66                         rdesc[13] = 8; /* Button/Variable Report Count */
  67                         rdesc[21] = 8; /* Button/Variable Usage Maximum */
  68                         rdesc[29] = 0; /* Button/Constant Report Count */
  69                 }
  70                 break;
  71         }
  72         return rdesc;
  73 }
  74
  75 static const struct hid_device_id elecom_devices[] = {
  76         { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
  77         { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_DEFT_WIRED) },
  78         { HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_DEFT_WIRELESS) },
  79         { }
  80 };
  81 MODULE_DEVICE_TABLE(hid, elecom_devices);
  82
  83 static struct hid_driver elecom_driver = {
  84         .name = "elecom",
  85         .id_table = elecom_devices,
  86         .report_fixup = elecom_report_fixup
  87 };
  88 module_hid_driver(elecom_driver);
  89
  90 MODULE_LICENSE("GPL");