linux/drivers/hid/hid-speedlink.c
Stefan Kriwanek 74bc695313 HID: Add driver to fix Speedlink VAD Cezanne support
Speedlink VAD Cezanne have a hardware bug that makes the cursor "jump" from one
place to another every now and then. The issue are relative motion events
erroneously reported by the device, each having a distance value of +256. This
256 can in fact never occur due to real motion, therefore those events can
safely be ignored.  The driver also drops useless EV_REL events with a value of
0, that the device sends every time it sends an "real" EV_REL or EV_KEY event.

Signed-off-by: Stefan Kriwanek <mail@stefankriwanek.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-06-08 09:45:37 +02:00

89 lines
2.3 KiB
C

/*
* HID driver for Speedlink Vicious and Divine Cezanne (USB mouse).
* Fixes "jumpy" cursor and removes nonexistent keyboard LEDS from
* the HID descriptor.
*
* Copyright (c) 2011 Stefan Kriwanek <mail@stefankriwanek.de>
*/
/*
* 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 <linux/usb.h>
#include "hid-ids.h"
#include "usbhid/usbhid.h"
static const struct hid_device_id speedlink_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_X_TENSIONS, USB_DEVICE_ID_SPEEDLINK_VAD_CEZANNE)},
{ }
};
static int speedlink_input_mapping(struct hid_device *hdev,
struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
{
/*
* The Cezanne mouse has a second "keyboard" USB endpoint for it is
* able to map keyboard events to the button presses.
* It sends a standard keyboard report descriptor, though, whose
* LEDs we ignore.
*/
switch (usage->hid & HID_USAGE_PAGE) {
case HID_UP_LED:
return -1;
}
return 0;
}
static int speedlink_event(struct hid_device *hdev, struct hid_field *field,
struct hid_usage *usage, __s32 value)
{
/* No other conditions due to usage_table. */
/* Fix "jumpy" cursor (invalid events sent by device). */
if (value == 256)
return 1;
/* Drop useless distance 0 events (on button clicks etc.) as well */
if (value == 0)
return 1;
return 0;
}
MODULE_DEVICE_TABLE(hid, speedlink_devices);
static const struct hid_usage_id speedlink_grabbed_usages[] = {
{ HID_GD_X, EV_REL, 0 },
{ HID_GD_Y, EV_REL, 1 },
{ HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
};
static struct hid_driver speedlink_driver = {
.name = "speedlink",
.id_table = speedlink_devices,
.usage_table = speedlink_grabbed_usages,
.input_mapping = speedlink_input_mapping,
.event = speedlink_event,
};
static int __init speedlink_init(void)
{
return hid_register_driver(&speedlink_driver);
}
static void __exit speedlink_exit(void)
{
hid_unregister_driver(&speedlink_driver);
}
module_init(speedlink_init);
module_exit(speedlink_exit);
MODULE_LICENSE("GPL");