usb_interrupt_msg — Builds an interrupt urb, sends it off and waits for completion
int usb_interrupt_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 interrupt 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.