From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752860Ab2GAMe5 (ORCPT ); Sun, 1 Jul 2012 08:34:57 -0400 Received: from juliette.telenet-ops.be ([195.130.137.74]:48409 "EHLO juliette.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751641Ab2GAMez (ORCPT ); Sun, 1 Jul 2012 08:34:55 -0400 Message-ID: <1341146090.4121.3.camel@piranha.localdomain> Subject: Re: Logitech HD Webcam C525 does not work when connected to USB 2 port, works on USB 3 From: Frederik Himpe To: Alan Stern Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Date: Sun, 01 Jul 2012 14:34:50 +0200 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.3-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2012-06-30 at 22:12 -0400, Alan Stern wrote: > On Sat, 30 Jun 2012, Frederik Himpe wrote: > > > Hello, > > > > I've got a Logitech HD Webcam C525 using the uvcvideo module and I use > > Linux 3.5 RC4. When this camera is connected to a USB2 port, it does not > > work most of the time. However it does work fine when connected to a USB > > 3 port. In Windows it works on both ports. > > ... > > > Complete dmesg and lsusb -v output about a failed attempt (on USB 2 > > port) and a succeeded attempt (on USB 3) can be found on > > http://artipc10.vub.ac.be/~frederik/webcam/ > > A usbmon trace would be more helpful. Or perhaps a pair of traces, one > for the USB-2 port and one for the USB-3 port. See the instructions in > Documentation/usb/usbmon.txt. OK, I created a usbmon trace both from the USB-2 port as the USB-3 port. During the trace, I connected the USB webcam to the USB port and started mplayer, which failed on USB-2 but worked fine on USB-3. The two traces can be found here: http://artipc10.vub.ac.be/~frederik/webcam/ Thanks! -- Frederik Himpe