1USB_CALC_BUS_TIME(9)         Host Controller APIs         USB_CALC_BUS_TIME(9)
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NAME

6       usb_calc_bus_time - approximate periodic transaction time in
7       nanoseconds
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SYNOPSIS

10       long usb_calc_bus_time(int speed, int is_input, int isoc,
11                              int bytecount);
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ARGUMENTS

14       speed
15           from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
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17       is_input
18           true iff the transaction sends data to the host
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20       isoc
21           true for isochronous transactions, false for interrupt ones
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23       bytecount
24           how many bytes in the transaction.
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RETURN

27       Approximate bus time in nanoseconds for a periodic transaction.
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NOTE

30       See USB 2.0 spec section 5.11.3; only periodic transfers need to be
31       scheduled in software, this function is only used for such scheduling.
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34Kernel Hackers Manual 3.10         June 2019              USB_CALC_BUS_TIME(9)
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