Configuring the Touchpad in Debian using udev no longer works. Now you have to configure it through xorg.
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xserver-xorg-input-synaptics 1.2.1-1 changed the handling of the synaptic touchpad driver from HAL to udev. Due to the switch, custom configuration files in /etc/hal/fdi/policy/ no longer work. In order to get the touchpad to tap to click, horizontal scroll, vertical scroll etc you need to write a udev rules file.
In this file you can add options and values for ever aspect of the synaptic touchpad driver and configure it to your finger size and personal preferences.
ACTION!="add|change", GOTO="xorg_synaptics_hubi_end"
KERNEL!="event*", GOTO="xorg_synaptics_hubi_end"
ENV{ID_INPUT_TOUCHPAD}!="1", GOTO="xorg_synaptics_hubi_end"
ENV{x11_driver}="synaptics"
ENV{x11_options.LeftEdge}="1600"
ENV{x11_options.RightEdge}="5000"
ENV{x11_options.TopEdge}="1600"
ENV{x11_options.BottomEdge}="4200"
ENV{x11_options.FingerLow}="24"
ENV{x11_options.FingerHigh}="28"
ENV{x11_options.FingerPress}="255"
ENV{x11_options.MaxTapTime}="180"
ENV{x11_options.MaxTapMove}="220"
ENV{x11_options.MaxDoubleTapTime}="180"
ENV{x11_options.SingleTapTimeout}="180"
ENV{x11_options.ClickTime }="100"
ENV{x11_options.FastTaps}="1"
ENV{x11_options.EmulateMidButtonTime}="80"
ENV{x11_options.EmulateTwoFingerMinZ}="66"
ENV{x11_options.EmulateTwoFingerMinW}="12"
ENV{x11_options.VerteScrollDelta}="100"
ENV{x11_options.HorizScrollDelta}="100"
ENV{x11_options.VertEdgeScroll}="true"
ENV{x11_options.HorizEdgeScroll}="true"
ENV{x11_options.CornerCoasting}="0"
ENV{x11_options.VertTwoFingerScroll}="false"
ENV{x11_options.HorizTwoFingerScroll}="false"
ENV{x11_options.MinSpeed}="0.4"
ENV{x11_options.MaxSpeed}="0.7"
ENV{x11_options.AccelFactor}="0.00995"
ENV{x11_options.EdgeMotionMinZ}="30"
ENV{x11_options.EdgeMotionMaxZ}="160"
ENV{x11_options.EdgeMotionMinSpeed}="1"
ENV{x11_options.EdgeMotionMaxSpeed}="400"
ENV{x11_options.EdgeMotionUseAlways}="0"
ENV{x11_options.UpDownScrolling}="1"
ENV{x11_options.LeftRightScrolling}="1"
ENV{x11_options.UpDownScrollRepeat}="1"
ENV{x11_options.LeftRightScrollRepeat}="1"
ENV{x11_options.ScrollButtonRepeat}="100"
ENV{x11_options.TouchpadOff}="0"
ENV{x11_options.GuestMouseOff}="0"
ENV{x11_options.LockedDrags}="0"
ENV{x11_options.LockedDragTimeout}="5000"
ENV{x11_options.RTCornerButton}="0"
ENV{x11_options.RBCornerButton}="0"
ENV{x11_options.LTCornerButton}="0"
ENV{x11_options.LBCornerButton}="0"
ENV{x11_options.TapButton1}="1"
ENV{x11_options.TapButton2}="2"
ENV{x11_options.TapButton3}="3"
ENV{x11_options.ClickFinger1}="1"
ENV{x11_options.ClickFinger2}="2"
ENV{x11_options.ClickFinger3}="0"
ENV{x11_options.CircularScrolling}="0"
ENV{x11_options.CircScrollTrigger}="0"
ENV{x11_options.CircScrollDelta}="0"
ENV{x11_options.PalmDetect}="false"
ENV{x11_options.PalmMinWidth}="10"
ENV{x11_options.PalmMinZ}="200"
ENV{x11_options.CoastingSpeed}="0"
ENV{x11_options.PressureMotionMinZ}="30"
ENV{x11_options.PressureMotionMaxZ}="160"
ENV{x11_options.PressureMotionMinFactor}="1"
ENV{x11_options.PressureMotionMaxFactor}="1"
ENV{x11_options.GrabEventDevice}="1"
ENV{x11_options.AreaLeftEdge}="0"
ENV{x11_options.AreaRightEdge}="0"
ENV{x11_options.AreaTopEdge}="0"
ENV{x11_options.AreaBottomEdge}="0"
ENV{x11_options.JumpyCursorThreshold}="0"
LABEL="xorg_synaptics_hubi_end"
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