From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joonyoung Shim <jy0922.shim@samsung.com>
Subject: Questions about Multi-touch Protocal
Date: Tue, 05 Jan 2010 15:18:00 +0900
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Cc: rydberg@euromail.se, dmitry.torokhov@gmail.com, jkosina@suse.cz

Hi, all.

I have some questions about Multi-touch(MT) Protocal.

First, what is the purpose of ABS_MT_TOUCH_MAJOR event? I wonder how
it is used at userspace side.

Should the ABS_MT_TOUCH_MAJOR be the mininum set of events for multi
touch? I'm not sure whether this question is valid because of first
question.

Finally, what is difference of ABS_MT_TOUCH_MAJOR and
ABS_MT_WIDTH_MAJOR?

I read the MT Protocol document of kernel, but i cannot understand above
things clearly.

Thanks.