path: root/Documentation/input
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authorPeter Hutterer <peter.hutterer@who-t.net>2013-05-31 16:29:44 +1000
committerHenrik Rydberg <rydberg@euromail.se>2013-06-13 21:32:00 +0200
commit257867dc8d893690c175c1f717f91c3b6d44a63d (patch)
treeef3f2404177a832d1cb1440179ed27f9788e7c63 /Documentation/input
parent317ddd256b9c24b0d78fa8018f80f1e495481a10 (diff)
Input: MT - Specify that ABS_MT_SLOT must have a minimum of 0
This is effectively already in force through input_mt_init_slots, and uinput too ignores the actual minimum. Since slots are a kernel-genenerated axis only, non-zero minimums make little sense and are likely to cause errors. Better to treat a non-zero minimum as kernel bug if it ever happens. Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net> Acked-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Diffstat (limited to 'Documentation/input')
1 files changed, 2 insertions, 0 deletions
diff --git a/Documentation/input/multi-touch-protocol.txt b/Documentation/input/multi-touch-protocol.txt
index 2c179613f81b..de139b18184a 100644
--- a/Documentation/input/multi-touch-protocol.txt
+++ b/Documentation/input/multi-touch-protocol.txt
@@ -80,6 +80,8 @@ Userspace can detect that a driver can report more total contacts than slots
by noting that the largest supported BTN_TOOL_*TAP event is larger than the
total number of type B slots reported in the absinfo for the ABS_MT_SLOT axis.
+The minimum value of the ABS_MT_SLOT axis must be 0.
Protocol Example A