Documentation/ABI/testing/sysfs-devices-platform-trackpoint

   1 What:           /sys/devices/platform/i8042/.../sensitivity
   2 Date:           Aug, 2005
   3 KernelVersion:  2.6.14
   4 Contact:        linux-input@vger.kernel.org
   5 Description:
   6                 (RW) Trackpoint sensitivity.
   7
   8 What:           /sys/devices/platform/i8042/.../intertia
   9 Date:           Aug, 2005
  10 KernelVersion:  2.6.14
  11 Contact:        linux-input@vger.kernel.org
  12 Description:
  13                 (RW) Negative inertia factor. High values cause the cursor to
  14                 snap backward when the trackpoint is released.
  15
  16 What:           /sys/devices/platform/i8042/.../reach
  17 Date:           Aug, 2005
  18 KernelVersion:  2.6.14
  19 Contact:        linux-input@vger.kernel.org
  20 Description:
  21                 (RW) Backup range for z-axis press.
  22
  23 What:           /sys/devices/platform/i8042/.../draghys
  24 Date:           Aug, 2005
  25 KernelVersion:  2.6.14
  26 Contact:        linux-input@vger.kernel.org
  27 Description:
  28                 (RW) The drag hysteresis controls how hard it is to drag with
  29                 z-axis pressed.
  30
  31 What:           /sys/devices/platform/i8042/.../mindrag
  32 Date:           Aug, 2005
  33 KernelVersion:  2.6.14
  34 Contact:        linux-input@vger.kernel.org
  35 Description:
  36                 (RW) Minimum amount of force needed to trigger dragging.
  37
  38 What:           /sys/devices/platform/i8042/.../speed
  39 Date:           Aug, 2005
  40 KernelVersion:  2.6.14
  41 Contact:        linux-input@vger.kernel.org
  42 Description:
  43                 (RW) Speed of the trackpoint cursor.
  44
  45 What:           /sys/devices/platform/i8042/.../thresh
  46 Date:           Aug, 2005
  47 KernelVersion:  2.6.14
  48 Contact:        linux-input@vger.kernel.org
  49 Description:
  50                 (RW) Minimum value for z-axis force required to trigger a press
  51                 or release, relative to the running average.
  52
  53 What:           /sys/devices/platform/i8042/.../upthresh
  54 Date:           Aug, 2005
  55 KernelVersion:  2.6.14
  56 Contact:        linux-input@vger.kernel.org
  57 Description:
  58                 (RW) The offset from the running average required to generate a
  59                 select (click) on z-axis on release.
  60
  61 What:           /sys/devices/platform/i8042/.../ztime
  62 Date:           Aug, 2005
  63 KernelVersion:  2.6.14
  64 Contact:        linux-input@vger.kernel.org
  65 Description:
  66                 (RW) This attribute determines how sharp a press has to be in
  67                 order to be recognized.
  68
  69 What:           /sys/devices/platform/i8042/.../jenks
  70 Date:           Aug, 2005
  71 KernelVersion:  2.6.14
  72 Contact:        linux-input@vger.kernel.org
  73 Description:
  74                 (RW) Minimum curvature in degrees required to generate a double
  75                 click without a release.
  76
  77 What:           /sys/devices/platform/i8042/.../skipback
  78 Date:           Aug, 2005
  79 KernelVersion:  2.6.14
  80 Contact:        linux-input@vger.kernel.org
  81 Description:
  82                 (RW) When the skipback bit is set, backup cursor movement during
  83                 releases from drags will be suppressed. The default value for
  84                 this bit is 0.
  85
  86 What:           /sys/devices/platform/i8042/.../ext_dev
  87 Date:           Aug, 2005
  88 KernelVersion:  2.6.14
  89 Contact:        linux-input@vger.kernel.org
  90 Description:
  91                 (RW) Disable (0) or enable (1) external pointing device.
  92
  93 What:           /sys/devices/platform/i8042/.../press_to_select
  94 Date:           Aug, 2005
  95 KernelVersion:  2.6.14
  96 Contact:        linux-input@vger.kernel.org
  97 Description:
  98                 (RW) Writing a value of 1 to this file will enable the Press to
  99                 Select functions like tapping the control stick to simulate a
 100                 left click, and writing 0 will disable it.
 101
 102 What:           /sys/devices/platform/i8042/.../drift_time
 103 Date:           Dec, 2014
 104 KernelVersion:  3.19
 105 Contact:        linux-input@vger.kernel.org
 106 Description:
 107                 (RW) This parameter controls the period of time to test for a
 108                 ‘hands off’ condition (i.e. when no force is applied) before a
 109                 drift (noise) calibration occurs.
 110
 111                 IBM Trackpoints have a feature to compensate for drift by
 112                 recalibrating themselves periodically. By default, if for 0.5
 113                 seconds there is no change in position, it's used as the new
 114                 zero. This duration is too low. Often, the calibration happens
 115                 when the trackpoint is in fact being used.