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usb_fill_int_urb(9) [centos man page]

USB_FILL_INT_URB(9)					  Host-Side Data Types and Macro				       USB_FILL_INT_URB(9)

NAME

       usb_fill_int_urb - macro to help initialize a interrupt urb

SYNOPSIS

       void usb_fill_int_urb(struct urb * urb, struct usb_device * dev, unsigned int pipe, void * transfer_buffer, int buffer_length,
			     usb_complete_t complete_fn, void * context, int interval);

ARGUMENTS

       urb
	   pointer to the urb to initialize.

       dev
	   pointer to the struct usb_device for this urb.

       pipe
	   the endpoint pipe

       transfer_buffer
	   pointer to the transfer buffer

       buffer_length
	   length of the transfer buffer

       complete_fn
	   pointer to the usb_complete_t function

       context
	   what to set the urb context to.

       interval
	   what to set the urb interval to, encoded like the endpoint descriptor's bInterval value.

DESCRIPTION

       Initializes a interrupt urb with the proper information needed to submit it to a device.

       Note that High Speed and SuperSpeed interrupt endpoints use a logarithmic encoding of the endpoint interval, and express polling intervals
       in microframes (eight per millisecond) rather than in frames (one per millisecond).

       Wireless USB also uses the logarithmic encoding, but specifies it in units of 128us instead of 125us. For Wireless USB devices, the
       interval is passed through to the host controller, rather than being translated into microframe units.

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014						       USB_FILL_INT_URB(9)

Check Out this Related Man Page

USB_POISON_URB(9)						   USB Core APIs						 USB_POISON_URB(9)

NAME

       usb_poison_urb - reliably kill a transfer and prevent further use of an URB

SYNOPSIS

       void usb_poison_urb(struct urb * urb);

ARGUMENTS

       urb
	   pointer to URB describing a previously submitted request, may be NULL

DESCRIPTION

       This routine cancels an in-progress request. It is guaranteed that upon return all completion handlers will have finished and the URB will
       be totally idle and cannot be reused. These features make this an ideal way to stop I/O in a disconnect callback. If the request has not
       already finished or been unlinked the completion handler will see urb->status == -ENOENT.

       After and while the routine runs, attempts to resubmit the URB will fail with error -EPERM. Thus even if the URB's completion handler
       always tries to resubmit, it will not succeed and the URB will become idle.

       The URB must not be deallocated while this routine is running. In particular, when a driver calls this routine, it must insure that the
       completion handler cannot deallocate the URB.

       This routine may not be used in an interrupt context (such as a bottom half or a completion handler), or when holding a spinlock, or in
       other situations where the caller can't schedule.

       This routine should not be called by a driver after its disconnect method has returned.

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014							 USB_POISON_URB(9)
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