usb_bulk_msg — Builds a bulk urb, sends it off and waits for completion
int usb_bulk_msg ( | struct usb_device * | usb_dev, |
| unsigned int | pipe, | |
| void * | data, | |
| int | len, | |
| int * | actual_length, | |
| int | timeout); |
usb_devpointer to the usb device to send the message to
pipeendpoint “pipe” to send the message to
datapointer to the data to send
lenlength in bytes of the data to send
actual_lengthpointer to a location to put the actual length transferred in bytes
timeouttime in msecs to wait for the message to complete before timing out (if 0 the wait is forever)
This function sends a simple bulk message to a specified endpoint and waits for the message to complete, or timeout.
If successful, it returns 0, otherwise a negative error number. The number of actual bytes transferred will be stored in the actual_length paramater.
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.