HID: Fix Speedlink VAD Cezanne support for some devices

Some devices of the "Speedlink VAD Cezanne" model need more aggressive fixing
than already done.

I made sure through testing that this patch would not interfere with the proper
working of a device that is bug-free. (The driver drops EV_REL events with
abs(val) >= 256, which are not achievable even on the highest laser resolution
hardware setting.)

Signed-off-by: Stefan Kriwanek <mail@stefankriwanek.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Stefan Kriwanek 2013-08-25 10:46:13 +02:00 committed by Jiri Kosina
parent 15261f6d8d
commit 06bb521911

View file

@ -3,7 +3,7 @@
* Fixes "jumpy" cursor and removes nonexistent keyboard LEDS from
* the HID descriptor.
*
* Copyright (c) 2011 Stefan Kriwanek <mail@stefankriwanek.de>
* Copyright (c) 2011, 2013 Stefan Kriwanek <dev@stefankriwanek.de>
*/
/*
@ -46,8 +46,13 @@ 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)
/* This fixes the "jumpy" cursor occuring due to invalid events sent
* by the device. Some devices only send them with value==+256, others
* don't. However, catching abs(value)>=256 is restrictive enough not
* to interfere with devices that were bug-free (has been tested).
*/
if (abs(value) >= 256)
return 1;
/* Drop useless distance 0 events (on button clicks etc.) as well */
if (value == 0)