On Fri, Dec 10, 2010 at 09:55:12AM -0800, Ping Cheng wrote: > On Thu, Dec 9, 2010 at 1:22 PM, Henrik Rydberg <rydberg@xxxxxxxxxxx> wrote: > > The recent input-mt interface changes together with > > recent discussions about pen and touch and support > > for legacy multitouch pads suggest that the documentation > > on MT tool types be expanded. This patch adds references > > to the new interface, and adds a section for MT_TOOL types, > > in particular documenting the use of MT_TOOL_ENVELOPE. > > > > Signed-off-by: Henrik Rydberg <rydberg@xxxxxxxxxxx> > > --- > > Documentation/input/multi-touch-protocol.txt | 37 ++++++++++++++++++------- > > 1 files changed, 26 insertions(+), 11 deletions(-) > > > > diff --git a/Documentation/input/multi-touch-protocol.txt b/Documentation/input/multi-touch-protocol.txt > > index 351fab8..e190943 100644 > > --- a/Documentation/input/multi-touch-protocol.txt > > +++ b/Documentation/input/multi-touch-protocol.txt > > @@ -169,12 +169,14 @@ described by adding the MINOR parameters, such that MAJOR and MINOR are the > > major and minor axis of an ellipse. Finally, the orientation of the oval > > shape can be describe with the ORIENTATION parameter. > > > > +For type A devices, further specification of the touch shape is possible > > +via ABS_MT_BLOB_ID. > > + > > The ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a > > -contact or a pen or something else. Devices with more granular information > > -may specify general shapes as blobs, i.e., as a sequence of rectangular > > -shapes grouped together by an ABS_MT_BLOB_ID. Finally, for the few devices > > -that currently support it, the ABS_MT_TRACKING_ID event may be used to > > -report contact tracking from hardware [5]. > > +contact or a pen or something else. Finally, the ABS_MT_TRACKING_ID event > > +may be used to track identified contacts over time [5]. In the type B > > +protocol, the use of ABS_MT_TOOL_TYPE and ABS_MT_TRACKING_ID is implicit > > +via the input_mt_report_slot_state() function. > > > > > > Event Semantics > > @@ -247,21 +249,34 @@ ABS_MT_TOOL_TYPE > > The type of approaching tool. A lot of kernel drivers cannot distinguish > > between different tool types, such as a finger or a pen. In such cases, the > > event should be omitted. The protocol currently supports MT_TOOL_FINGER and > > -MT_TOOL_PEN and MT_TOOL_ENVELOPE [2]. > > +MT_TOOL_PEN and MT_TOOL_ENVELOPE [2]. For type B devices, this event is > > +handled by input core, via the input_mt interface. > > + > > +- The MT_TOOL_FINGER type is the default, and represents a finger touch. > > + > > +- The MT_TOOL_PEN type represents a pen, and the list of related tools is > > +expected to grow with time. > > + > > +- The MT_TOOL_ENVELOPE type is used to indicate that the contact position > > +is not well-defined, and is only used for legacy hardware. The real contact > > +positions are to be found within the bounding rectangle formed by the > > +envelope contact positions. > > Can we make MT_TOOL_ENVELOPE cover a bit more cases by: > > 1. Removing ", and is only used for legacy hardware"; > 2. Adding "Or the number of contacts inside the bounding rectangle is > reported if hardware provides the number but not the real contact > positions" to the end of the paragraph. Are you saying that there is upcoming hardware models that do not report individual contacts? -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
