linux/drivers/hid/hid-elecom.c
Tomasz Kramkowski fbb77e88f0 HID: elecom: add support for EX-G M-XT4DRBK trackball
This patch enables the 6th button on the ELECOM EX-G M-XT4DRBK
trackball mouse.

This is a left handed EX-G variant which only comes in a wireless (D)
model. It has a total of 6 buttons but one of these is not available
because of how the HID descriptor is configured.

Signed-off-by: Tomasz Kramkowski <tk@the-tk.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-03-06 15:15:47 +01:00

104 lines
3.7 KiB
C

/*
* HID driver for ELECOM devices:
* - BM084 Bluetooth Mouse
* - EX-G Trackballs (M-XT3DRBK, M-XT3URBK, M-XT4DRBK)
* - DEFT Trackballs (M-DT1DRBK, M-DT1URBK, M-DT2DRBK, M-DT2URBK)
* - HUGE Trackballs (M-HT1DRBK, M-HT1URBK)
*
* Copyright (c) 2010 Richard Nauber <Richard.Nauber@gmail.com>
* Copyright (c) 2016 Yuxuan Shui <yshuiv7@gmail.com>
* Copyright (c) 2017 Diego Elio Pettenò <flameeyes@flameeyes.eu>
* Copyright (c) 2017 Alex Manoussakis <amanou@gnu.org>
* Copyright (c) 2017 Tomasz Kramkowski <tk@the-tk.com>
*/
/*
* 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/hid.h>
#include <linux/module.h>
#include "hid-ids.h"
/*
* Certain ELECOM mice misreport their button count meaning that they only work
* correctly with the ELECOM mouse assistant software which is unavailable for
* Linux. A four extra INPUT reports and a FEATURE report are described by the
* report descriptor but it does not appear that these enable software to
* control what the extra buttons map to. The only simple and straightforward
* solution seems to involve fixing up the report descriptor.
*
* Report descriptor format:
* Positions 13, 15, 21 and 31 store the button bit count, button usage minimum,
* button usage maximum and padding bit count respectively.
*/
#define MOUSE_BUTTONS_MAX 8
static void mouse_button_fixup(struct hid_device *hdev,
__u8 *rdesc, unsigned int rsize,
int nbuttons)
{
if (rsize < 32 || rdesc[12] != 0x95 ||
rdesc[14] != 0x75 || rdesc[15] != 0x01 ||
rdesc[20] != 0x29 || rdesc[30] != 0x75)
return;
hid_info(hdev, "Fixing up Elecom mouse button count\n");
nbuttons = clamp(nbuttons, 0, MOUSE_BUTTONS_MAX);
rdesc[13] = nbuttons;
rdesc[21] = nbuttons;
rdesc[31] = MOUSE_BUTTONS_MAX - nbuttons;
}
static __u8 *elecom_report_fixup(struct hid_device *hdev, __u8 *rdesc,
unsigned int *rsize)
{
switch (hdev->product) {
case USB_DEVICE_ID_ELECOM_BM084:
/* The BM084 Bluetooth mouse includes a non-existing horizontal
* wheel in the HID descriptor. */
if (*rsize >= 48 && rdesc[46] == 0x05 && rdesc[47] == 0x0c) {
hid_info(hdev, "Fixing up Elecom BM084 report descriptor\n");
rdesc[47] = 0x00;
}
break;
case USB_DEVICE_ID_ELECOM_M_XT3URBK:
case USB_DEVICE_ID_ELECOM_M_XT3DRBK:
case USB_DEVICE_ID_ELECOM_M_XT4DRBK:
mouse_button_fixup(hdev, rdesc, *rsize, 6);
break;
case USB_DEVICE_ID_ELECOM_M_DT1URBK:
case USB_DEVICE_ID_ELECOM_M_DT1DRBK:
case USB_DEVICE_ID_ELECOM_M_HT1URBK:
case USB_DEVICE_ID_ELECOM_M_HT1DRBK:
mouse_button_fixup(hdev, rdesc, *rsize, 8);
break;
}
return rdesc;
}
static const struct hid_device_id elecom_devices[] = {
{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3URBK) },
{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT3DRBK) },
{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_XT4DRBK) },
{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_DT1URBK) },
{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_DT1DRBK) },
{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1URBK) },
{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_M_HT1DRBK) },
{ }
};
MODULE_DEVICE_TABLE(hid, elecom_devices);
static struct hid_driver elecom_driver = {
.name = "elecom",
.id_table = elecom_devices,
.report_fixup = elecom_report_fixup
};
module_hid_driver(elecom_driver);
MODULE_LICENSE("GPL");