[SOLVED] How to genarate interrupt???

iam doing a project which is suppose to count the status of gpio pin continuosly which is high when a signal is applied on it.i have to count its status untill any key is pressed..when a key is pressed i have to display the count.iam successfully counting the status but iam not able to generate interrupt.iam using linux2.6 kernel on at91sam9261 board.
can any body help me to sort out this problem...

You'll need a interrupt service routine in your driver and see some registers (Interurupt mask, gpio register). Check AT91SAM9261 datasheet to see which registers to set.
You may want to ask on linux4sam forum if you want a more accurate answer.