[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <201001110925.53711.oliver@neukum.org>
Date: Mon, 11 Jan 2010 09:25:53 +0100
From: Oliver Neukum <oliver@...kum.org>
To: Steven Xu <linuxkernel.xxz@...il.com>, linux-usb@...r.kernel.org
Cc: linux-kernel@...r.kernel.org
Subject: Re: A QUESTION ABOUT USB DRIVER
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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists