From 0d9d93c411c9351ba186f5ec910b10da7c1d9d14 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Thu, 12 Apr 2007 01:31:55 -0400 Subject: [PATCH] Input: mousedev - fix sudden warps with touchpads Pete Zaitcev reports that with his touchpad, if he lifts the finger and places it elsewhere, the pointer sometimes warps dramatically. This happens because we don't store coordinates unless we detect a touch so sometimes we have stale coordinates in queue (from where the finger left the pad) and averaging makes cursor to jump across the screen. The solution is to always store the latest coordinates. Signed-off-by: Dmitry Torokhov --- drivers/input/mousedev.c | 51 ++++++++++++++++++++-------------------- 1 file changed, 26 insertions(+), 25 deletions(-) diff --git a/drivers/input/mousedev.c b/drivers/input/mousedev.c index 764970f5da2e..3b8011c56c86 100644 --- a/drivers/input/mousedev.c +++ b/drivers/input/mousedev.c @@ -124,32 +124,33 @@ static void mousedev_touchpad_event(struct input_dev *dev, struct mousedev *mous int size, tmp; enum { FRACTION_DENOM = 128 }; - if (mousedev->touch) { - size = dev->absmax[ABS_X] - dev->absmin[ABS_X]; - if (size == 0) - size = 256 * 2; - - switch (code) { - case ABS_X: - fx(0) = value; - if (mousedev->pkt_count >= 2) { - tmp = ((value - fx(2)) * (256 * FRACTION_DENOM)) / size; - tmp += mousedev->frac_dx; - mousedev->packet.dx = tmp / FRACTION_DENOM; - mousedev->frac_dx = tmp - mousedev->packet.dx * FRACTION_DENOM; - } - break; + switch (code) { + case ABS_X: + fx(0) = value; + if (mousedev->touch && mousedev->pkt_count >= 2) { + size = dev->absmax[ABS_X] - dev->absmin[ABS_X]; + if (size == 0) + size = 256 * 2; + tmp = ((value - fx(2)) * (256 * FRACTION_DENOM)) / size; + tmp += mousedev->frac_dx; + mousedev->packet.dx = tmp / FRACTION_DENOM; + mousedev->frac_dx = tmp - mousedev->packet.dx * FRACTION_DENOM; + } + break; - case ABS_Y: - fy(0) = value; - if (mousedev->pkt_count >= 2) { - tmp = -((value - fy(2)) * (256 * FRACTION_DENOM)) / size; - tmp += mousedev->frac_dy; - mousedev->packet.dy = tmp / FRACTION_DENOM; - mousedev->frac_dy = tmp - mousedev->packet.dy * FRACTION_DENOM; - } - break; - } + case ABS_Y: + fy(0) = value; + if (mousedev->touch && mousedev->pkt_count >= 2) { + /* use X size to keep the same scale */ + size = dev->absmax[ABS_X] - dev->absmin[ABS_X]; + if (size == 0) + size = 256 * 2; + tmp = -((value - fy(2)) * (256 * FRACTION_DENOM)) / size; + tmp += mousedev->frac_dy; + mousedev->packet.dy = tmp / FRACTION_DENOM; + mousedev->frac_dy = tmp - mousedev->packet.dy * FRACTION_DENOM; + } + break; } } -- 2.20.1