NAME¶

usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion

SYNOPSIS¶

int usb_interrupt_msg(struct usb_device * usb_dev, unsigned int pipe, void * data, int len, int * actual_length, int timeout);

ARGUMENTS¶

usb_dev

pipe

data

len

actual_length

timeout

CONTEXT¶

!in_interrupt ()

DESCRIPTION¶

This function sends a simple interrupt 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.

COPYRIGHT¶