lkml.org 
[lkml]   [2012]   [Jan]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] Input: Document the device properties
    On 01/30/2012 01:23 PM, Jussi Pakkanen wrote:
    > On 01/30/2012 10:35 AM, Henrik Rydberg wrote:
    >> +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 the corresponding bounding box is known. For such
    >> +touchpads, the semi-mt property should be set.
    >
    > A "corresponding bounding box" usually means "a bounding box that
    > contains all touches on the touchpad". I've been told (though I have not
    > checked it myself) that there are devices that don't do this. They only
    > report a bounding box for some subset of touches. If this is the case,
    > it should be documented here.

    Yeah, I thought Henrik's definition was correct for a long time, but
    when Derek Foreman (I think) proposed some patches for the latest
    synaptics devices I took a closer look at my semi-mt synaptics trackpad.
    The coordinates it gave were locations based on two of the touches. When
    three touches are on the touchpad, it gave a bounding box of two of the
    touches, and there's no way to tell which two.

    -- Chase



    \
     
     \ /
      Last update: 2012-01-30 18:07    [W:0.023 / U:33.220 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site