Linux request number request_threaded_irq

Question

I am trying to write a simple Linux kernel module that uses an existing I2C module. An existing i2c module requires the irq number (passed through the structure i2c_board_info), which is then passed to the i2c module as the first parameter in request_threaded_irq(...).

I want the irq I was going through with to run periodically (say, every 100 ms), and I thought that a suitable path for this purpose, but I do not see any way to translate the tasklet to the irq number that can be passed to request_threaded_irq(). Am I really wrong? Is there a way to do what I'm trying to do?