I am trying to use a usb controller on the HPS portion of the cyclone5 soc development board. i am trying to run the linux application on hard processor. which folder create the peripheral API?
I am unsure what you meant by which folder to initiate the peripheral API.
We do have an example to interface the USB PHY to the HPS, you might want to take a look:
More info regarding the USB controller for Cyclone V: