usb_calc_bus_time(9) centos man page | unix.com

USB_CALC_BUS_TIME(9)					       Host Controller APIs					      USB_CALC_BUS_TIME(9)

NAME
       usb_calc_bus_time - approximate periodic transaction time in nanoseconds

SYNOPSIS
       long usb_calc_bus_time(int speed, int is_input, int isoc, int bytecount);

ARGUMENTS
       speed
	   from dev->speed; USB_SPEED_{LOW,FULL,HIGH}

       is_input
	   true iff the transaction sends data to the host

       isoc
	   true for isochronous transactions, false for interrupt ones

       bytecount
	   how many bytes in the transaction.

RETURN
       Approximate bus time in nanoseconds for a periodic transaction.

NOTE
       See USB 2.0 spec section 5.11.3; only periodic transfers need to be scheduled in software, this function is only used for such scheduling.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						      USB_CALC_BUS_TIME(9)