[PATCH 4.0 052/105] Input: alps - do not reduce trackpoint speed by half

From: Greg Kroah-Hartman
Date: Fri Jun 19 2015 - 17:15:55 EST

4.0-stable review patch. If anyone has any objections, please let me know.


From: Hans de Goede <hdegoede@xxxxxxxxxx>

commit 088df2ccef75754cc16a6ba31829d23bcb2b68ed upstream.

On some v7 devices (e.g. Lenovo-E550) the deltas reported are typically
only in the 0-1 range dividing this by 2 results in a range of 0-0.

And even for v7 devices where this does not lead to making the trackstick
entirely unusable, it makes it twice as slow as before we added v7 support
and were using the ps/2 mouse emulation of the dual point setup.

If some kind of generic slowdown is actually necessary for some devices,
then that belongs in userspace, not in the kernel.

Reported-and-tested-by: Rico Moorman <rico.moorman@xxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxx>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/input/mouse/alps.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

--- a/drivers/input/mouse/alps.c
+++ b/drivers/input/mouse/alps.c
@@ -1042,9 +1042,8 @@ static void alps_process_trackstick_pack
right = (packet[1] & 0x02) >> 1;
middle = (packet[1] & 0x04) >> 2;

- /* Divide 2 since trackpoint's speed is too fast */
- input_report_rel(dev2, REL_X, (char)x / 2);
- input_report_rel(dev2, REL_Y, -((char)y / 2));
+ input_report_rel(dev2, REL_X, (char)x);
+ input_report_rel(dev2, REL_Y, -((char)y));

input_report_key(dev2, BTN_LEFT, left);
input_report_key(dev2, BTN_RIGHT, right);

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