What is the dataflow of using touchscreen with tslib?

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http://stackoverflow.com – I don't understand how tslib works. Let's say I have a serial touchscreen, in my understanding the data flows in the following way: ts press -> serial port -> ts driver -> tslib -> device file (like /dev/input/eventX) Is it right? Or do I need to insert some code between ts driver and tslib so that they can communicate? (HowTos)