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| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2021-03-25 21:46:10 +0300 |
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| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2021-03-25 21:46:10 +0300 |
| commit | 5acac83bf2e42f51ab9fd315d657798754bf0bb8 (patch) | |
| tree | 564be60664226649f00798cc3afb72d72d0ed24d /Documentation/input | |
| parent | 84c36ab7a6ddeab213c979d22b6372f71d738862 (diff) | |
| parent | 0d02ec6b3136c73c09e7859f0d0e4e2c4c07b49b (diff) | |
| download | linux-5acac83bf2e42f51ab9fd315d657798754bf0bb8.tar.xz | |
Merge tag 'v5.12-rc4' into next
Sync up with the mainline to bring in newest APIs.
Diffstat (limited to 'Documentation/input')
| -rw-r--r-- | Documentation/input/event-codes.rst | 15 | ||||
| -rw-r--r-- | Documentation/input/multi-touch-protocol.rst | 4 |
2 files changed, 19 insertions, 0 deletions
diff --git a/Documentation/input/event-codes.rst b/Documentation/input/event-codes.rst index b24b5343f5eb..3118fc1c1e26 100644 --- a/Documentation/input/event-codes.rst +++ b/Documentation/input/event-codes.rst @@ -236,6 +236,21 @@ A few EV_ABS codes have special meanings: - Used to describe multitouch input events. Please see multi-touch-protocol.txt for details. +* ABS_PRESSURE/ABS_MT_PRESSURE: + + - For touch devices, many devices converted contact size into pressure. + A finger flattens with pressure, causing a larger contact area and thus + pressure and contact size are directly related. This is not the case + for other devices, for example digitizers and touchpads with a true + pressure sensor ("pressure pads"). + + A device should set the resolution of the axis to indicate whether the + pressure is in measurable units. If the resolution is zero, the + pressure data is in arbitrary units. If the resolution is nonzero, the + pressure data is in units/gram. For example, a value of 10 with a + resolution of 1 represents 10 gram, a value of 10 with a resolution on + 1000 represents 10 microgram. + EV_SW ----- diff --git a/Documentation/input/multi-touch-protocol.rst b/Documentation/input/multi-touch-protocol.rst index 307fe22d9668..21c1e6a22888 100644 --- a/Documentation/input/multi-touch-protocol.rst +++ b/Documentation/input/multi-touch-protocol.rst @@ -260,6 +260,10 @@ ABS_MT_PRESSURE of TOUCH and WIDTH for pressure-based devices or any device with a spatial signal intensity distribution. + If the resolution is zero, the pressure data is in arbitrary units. + If the resolution is nonzero, the pressure data is in units/gram. See + :ref:`input-event-codes` for details. + ABS_MT_DISTANCE The distance, in surface units, between the contact and the surface. Zero distance means the contact is touching the surface. A positive number means |