I was getting a problem with DirectFB and touchscreen. The df_windows example didn’t work correctly it was uncalibrated, the cursor didn’t was showed at pen stylus position.
The problem was caused because DirectFB was just using the Linux Input (/dev/input/event1) instead the tslib device (/dev/input/tslib0) because tslib0 didn’t exist. Then after to calibrate the toochscreen with tslib (ts_calibrate) DirectFB still uncalibrated.
Then to solve this problem I do that:
rm -f /etc/pointercal
Solved the problem!