From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752555Ab0AKIZG (ORCPT ); Mon, 11 Jan 2010 03:25:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752187Ab0AKIZF (ORCPT ); Mon, 11 Jan 2010 03:25:05 -0500 Received: from smtp-out003.kontent.com ([81.88.40.217]:53754 "EHLO smtp-out003.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752132Ab0AKIZF (ORCPT ); Mon, 11 Jan 2010 03:25:05 -0500 From: Oliver Neukum To: Steven Xu , linux-usb@vger.kernel.org Subject: Re: A QUESTION ABOUT USB DRIVER Date: Mon, 11 Jan 2010 09:25:53 +0100 User-Agent: KMail/1.12.2 (Linux/2.6.32-0.1-default; KDE/4.3.1; x86_64; ; ) Cc: linux-kernel@vger.kernel.org References: <1fd295ee1001102114p1b74336q16bb35d973b40c1c@mail.gmail.com> In-Reply-To: <1fd295ee1001102114p1b74336q16bb35d973b40c1c@mail.gmail.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201001110925.53711.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Montag, 11. Januar 2010 06:14:31 schrieb Steven Xu: > output: usb 1-1: device descriptor read/64, error -71 > > > in drivers/usb/core/hub.c line 2250 > when a udisk inserted run to here > for (j = 0; j < 3; ++j) { > buf->bMaxPacketSize0 = 0; > > r = usb_control_msg(udev, usb_rcvaddr0pipe(), > USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, > USB_DT_DEVICE << 8, 0, > buf, GET_DESCRIPTOR_BUFSIZE, > (i ? USB_CTRL_GET_TIMEOUT : 1000)); > return r=-74, > > WHAT IS THE POSSIBEL REASON FOR THIS? > THANKS! This is -EPROTO. It means that a low level error on the wire happened, for example a device sent a malformed package. This is a very unspecific error. HTH Oliver