Man page 9 : usb_function_deactivate

usb_function_deactivate - prevent function and gadget enumeration

int usb_function_deactivate(struct usb_function *  function );

function
    the function that isnAqt yet ready to respond

Blocks response of the gadget driver to host enumeration by preventing the data line pullup from being activated. This is normally called during bind() processing to change from the initial « ready to respond » state, or when a required resource becomes available.

For example, drivers that serve as a passthrough to a userspace daemon can block enumeration unless that daemon (such as an OBEX, MTP, or print server) is ready to handle host requests.

Not all systems support software control of their USB peripheral data pullups.

Returns zero on success, else negative errno.

David Brownell <>
    Author.