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authorLinus Torvalds <torvalds@linux-foundation.org>2010-04-15 11:49:55 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-04-15 11:49:55 -0700
commit00eef7bd01c7598d195699983c5290d901df19ad (patch)
tree14ba0178fc2c5e807282132e689236965b889e91 /Documentation/input
parent250541fca717a5c9b0d3710e737b2ca32ebb6fbc (diff)
parent014f61504af276ba9d9544d8a7401d8f8526eb73 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: wacom - switch mode upon system resume Revert "Input: wacom - merge out and in prox events" Input: matrix_keypad - allow platform to disable key autorepeat Input: ALPS - add signature for HP Pavilion dm3 laptops Input: i8042 - spelling fix Input: sparse-keymap - implement safer freeing of the keymap Input: update the status of the Multitouch X driver project Input: clarify the no-finger event in multitouch protocol Input: bcm5974 - retract efi-broken suspend_resume Input: sparse-keymap - free the right keymap on error
Diffstat (limited to 'Documentation/input')
-rw-r--r--Documentation/input/multi-touch-protocol.txt23
1 files changed, 17 insertions, 6 deletions
diff --git a/Documentation/input/multi-touch-protocol.txt b/Documentation/input/multi-touch-protocol.txt
index 8490480ce43..c0fc1c75fd8 100644
--- a/Documentation/input/multi-touch-protocol.txt
+++ b/Documentation/input/multi-touch-protocol.txt
@@ -68,6 +68,22 @@ like:
SYN_MT_REPORT
SYN_REPORT
+Here is the sequence after lifting one of the fingers:
+
+ ABS_MT_POSITION_X
+ ABS_MT_POSITION_Y
+ SYN_MT_REPORT
+ SYN_REPORT
+
+And here is the sequence after lifting the remaining finger:
+
+ SYN_MT_REPORT
+ SYN_REPORT
+
+If the driver reports one of BTN_TOUCH or ABS_PRESSURE in addition to the
+ABS_MT events, the last SYN_MT_REPORT event may be omitted. Otherwise, the
+last SYN_REPORT will be dropped by the input core, resulting in no
+zero-finger event reaching userland.
Event Semantics
---------------
@@ -217,11 +233,6 @@ where examples can be found.
difference between the contact position and the approaching tool position
could be used to derive tilt.
[2] The list can of course be extended.
-[3] The multi-touch X driver is currently in the prototyping stage. At the
-time of writing (April 2009), the MT protocol is not yet merged, and the
-prototype implements finger matching, basic mouse support and two-finger
-scrolling. The project aims at improving the quality of current multi-touch
-functionality available in the Synaptics X driver, and in addition
-implement more advanced gestures.
+[3] Multitouch X driver project: http://bitmath.org/code/multitouch/.
[4] See the section on event computation.
[5] See the section on finger tracking.