AM335x ecap modules not into the isr function

Hi,all I set the ecap modules to capture mode,when I insmod the driver modules,use the platform_driver,if the probe function is not run finish(as example:when I add while(1) statement before the return statement of probe function),the interrupt isr can work normal. But when if no "while(1)"statement before the "return" statement of probe function, if platform_driver_register finished the isr is not into anymore. can help me solve the problem?