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Diffstat (limited to 'Documentation/input/event-codes.rst')
-rw-r--r-- | Documentation/input/event-codes.rst | 33 |
1 files changed, 29 insertions, 4 deletions
diff --git a/Documentation/input/event-codes.rst b/Documentation/input/event-codes.rst index b24b5343f5eb..b4557462edd7 100644 --- a/Documentation/input/event-codes.rst +++ b/Documentation/input/event-codes.rst @@ -137,7 +137,11 @@ A few EV_KEY codes have special meanings: code should be set to a value of 1. When the tool is no longer interacting with the input device, the BTN_TOOL_<name> code should be reset to 0. All trackpads, tablets, and touchscreens should use at least one BTN_TOOL_<name> - code when events are generated. + code when events are generated. Likewise all trackpads, tablets, and + touchscreens should export only one BTN_TOOL_<name> at a time. To not break + existing userspace, it is recommended to not switch tool in one EV_SYN frame + but first emitting the old BTN_TOOL_<name> at 0, then emit one SYN_REPORT + and then set the new BTN_TOOL_<name> at 1. * BTN_TOUCH: @@ -231,11 +235,32 @@ A few EV_ABS codes have special meanings: BTN_TOOL_<name> signals the type of tool that is currently detected by the hardware and is otherwise independent of ABS_DISTANCE and/or BTN_TOUCH. +* ABS_PROFILE: + + - Used to describe the state of a multi-value profile switch. An event is + emitted only when the selected profile changes, indicating the newly + selected profile value. + * ABS_MT_<name>: - 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 non-zero, 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 of + 1000 represents 10 microgram. + EV_SW ----- @@ -329,7 +354,7 @@ INPUT_PROP_BUTTONPAD For touchpads where the button is placed beneath the surface, such that pressing down on the pad causes a button click, this property should be -set. Common in clickpad notebooks and macbooks from 2009 and onwards. +set. Common in Clickpad notebooks and Macbooks from 2009 and onwards. Originally, the buttonpad property was coded into the bcm5974 driver version field under the name integrated button. For backwards @@ -341,7 +366,7 @@ INPUT_PROP_SEMI_MT Some touchpads, most common between 2008 and 2011, can detect the presence of multiple contacts without resolving the individual positions; only the number of contacts and a rectangular shape is known. For such -touchpads, the semi-mt property should be set. +touchpads, the SEMI_MT property should be set. Depending on the device, the rectangle may enclose all touches, like a bounding box, or just some of them, for instance the two most recent @@ -379,7 +404,7 @@ Guidelines ========== The guidelines below ensure proper single-touch and multi-finger functionality. -For multi-touch functionality, see the multi-touch-protocol.txt document for +For multi-touch functionality, see the multi-touch-protocol.rst document for more information. Mice |