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I need to enable gesture detection (in userspace) from a multi-touch synaptics touch pad on linux. Reading from the mouse device file (/dev/input/mouse0) for the touchpad, I've figured out that it's the PS/2 protocol.

In short, thats 1 bit for: XY sign and overflow, 3 mouse buttons, and a permanent '1' Followed by 1 byte for the X delta and Y delta.

That totals 3 bytes. But I don't see any way to detect which finger a packet 'belongs' to when more than one finger is on the touch pad. Suggestions?

mamidon
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  • Not positive, but I believe you need to use the event interface, not the mouse interface. – Zan Lynx Apr 28 '11 at 22:54
  • Two links of possible value: http://bitmath.org/code/mtdev/ and http://www.mjmwired.net/kernel/Documentation/input/multi-touch-protocol.txt – Zan Lynx Apr 28 '11 at 22:57

1 Answers1

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That's not the right way to do it. The mouse device file you are seeing is emulating a standard mouse.

You will need to detect multi touch events. See:

https://wiki.ubuntu.com/Multitouch/Testing/CheckingMTDevice

JonnyRo
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