| From 06bb5219118fb098f4b0c7dcb484b28a52bf1c14 Mon Sep 17 00:00:00 2001 |
| From: Stefan Kriwanek <dev@stefankriwanek.de> |
| Date: Sun, 25 Aug 2013 10:46:13 +0200 |
| Subject: HID: Fix Speedlink VAD Cezanne support for some devices |
| |
| From: Stefan Kriwanek <dev@stefankriwanek.de> |
| |
| commit 06bb5219118fb098f4b0c7dcb484b28a52bf1c14 upstream. |
| |
| 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> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/hid/hid-speedlink.c | 11 ++++++++--- |
| 1 file changed, 8 insertions(+), 3 deletions(-) |
| |
| --- a/drivers/hid/hid-speedlink.c |
| +++ b/drivers/hid/hid-speedlink.c |
| @@ -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_de |
| 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) |
