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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)

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)

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USB_BULK_MSG(9) 						   USB Core APIs						   USB_BULK_MSG(9)

usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion SYNOPSIS
int usb_bulk_msg(struct usb_device * usb_dev, unsigned int pipe, void * data, int len, int * actual_length, int timeout); ARGUMENTS
usb_dev pointer to the usb device to send the message to pipe endpoint "pipe" to send the message to data pointer to the data to send len length in bytes of the data to send actual_length pointer to a location to put the actual length transferred in bytes timeout time in msecs to wait for the message to complete before timing out (if 0 the wait is forever) CONTEXT
!in_interrupt () DESCRIPTION
This function sends a simple bulk message to a specified endpoint and waits for the message to complete, or timeout. Don't use this function from within an interrupt context, like a bottom half handler. If you need an asynchronous message, or need to send a message from within interrupt context, use usb_submit_urb If a thread in your driver uses this call, make sure your disconnect method can wait for it to complete. Since you don't have a handle on the URB used, you can't cancel the request. Because there is no usb_interrupt_msg and no USBDEVFS_INTERRUPT ioctl, users are forced to abuse this routine by using it to submit URBs for interrupt endpoints. We will take the liberty of creating an interrupt URB (with the default interval) if the target is an interrupt endpoint. RETURN
If successful, 0. Otherwise a negative error number. The number of actual bytes transferred will be stored in the actual_length paramater. COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 USB_BULK_MSG(9)
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