USB_CLEAR_HALT

Section: (9)
Updated: 17 July 2003
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NAME

usb_clear_halt - tells device to clear endpoint halt/stall condition  

SYNOPSIS

int usb_clear_halt (struct usb_device * dev, int pipe);  

ARGUMENTS

dev
device whose endpoint is halted
pipe
endpoint ``pipe'' being cleared
 

CONTEXT

!in_interrupt ()  

DESCRIPTION

This is used to clear halt conditions for bulk and interrupt endpoints, as reported by URB completion status. Endpoints that are halted are sometimes referred to as being ``stalled''. Such endpoints are unable to transmit or receive data until the halt status is cleared. Any URBs queued for such an endpoint should normally be unlinked by the driver before clearing the halt condition, as described in sections 5.7.5 and 5.8.5 of the USB 2.0 spec.

Note that control and isochronous endpoints don't halt, although control endpoints report ``protocol stall'' (for unsupported requests) using the same status code used to report a true stall.

This call is synchronous, and may not be used in an interrupt context.

Returns zero on success, or else the status code returned by the underlying usb_control_msg call.  

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 2.5.71.


 

Index

NAME
SYNOPSIS
ARGUMENTS
CONTEXT
DESCRIPTION
ABOUT THIS DOCUMENT

This document was created by man2html, using the manual pages.
Time: 02:18:37 GMT, July 17, 2003