USB_CONTROL_MSG

Section: (9)
Updated: 17 July 2003
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NAME

usb_control_msg - Builds a control urb, sends it off and waits for completion  

SYNOPSIS

int usb_control_msg (struct usb_device * dev, unsigned int pipe, __u8 request, __u8 requesttype, __u16 value, __u16 index, void * data, __u16 size, int timeout);  

ARGUMENTS

dev
pointer to the usb device to send the message to
pipe
endpoint ``pipe'' to send the message to
request
USB message request value
requesttype
USB message request type value
value
USB message value
index
USB message index value
data
pointer to the data to send
size
length in bytes of the data to send
timeout
time in jiffies 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 control message to a specified endpoint and waits for the message to complete, or timeout.

If successful, it returns the number of bytes transferred, otherwise a negative error number.

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.  

ABOUT THIS DOCUMENT

This documentation is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

For more details see the file COPYING in the source distribution of Linux.

If you have comments on the formatting of this manpage, then please contact Michael Still (mikal@stillhq.com).

This documentation was generated with kernel version 2.5.73.


 

Index

NAME
SYNOPSIS
ARGUMENTS
CONTEXT
DESCRIPTION
ABOUT THIS DOCUMENT

This document was created by man2html, using the manual pages.
Time: 02:52:23 GMT, July 17, 2003