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Date: Mon, 11 Jan 2010 13:14:31 +0800
Message-ID: <1fd295ee1001102114p1b74336q16bb35d973b40c1c@mail.gmail.com>
Subject: A QUESTION ABOUT USB DRIVER
From: Steven Xu <linuxkernel.xxz@gmail.com>
To: linux-kernel@vger.kernel.org
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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!