From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756012Ab2GKGLT (ORCPT ); Wed, 11 Jul 2012 02:11:19 -0400 Received: from moutng.kundenserver.de ([212.227.17.8]:58851 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755672Ab2GKGLS (ORCPT ); Wed, 11 Jul 2012 02:11:18 -0400 Date: Wed, 11 Jul 2012 08:11:14 +0200 From: Heinz Diehl To: linux-kernel@vger.kernel.org Cc: Frederik Himpe , USB list , Alan Stern Subject: Re: Logitech HD Webcam C525 does not work when connected to USB 2 port, works on USB 3 Message-ID: <20120711061114.GA1596@fancy-poultry.org> References: <1341516932.4164.10.camel@piranha.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: private site OpenPGP: id=898F89DE; url=http://www.fritha.org/htd.asc User-Agent: Mutt/1.5.21+59 (8fabaffc2c00) (2011-07-01) X-Provags-ID: V02:K0:pwvaNYRb3eTAG9xnBz3Uh65UxPRTGAOfDL0k/+vQLMs fhd8louN6nz88WteSufMVLQJ+cTyrYmn6AlUoWyo3FcYbMga6l rm4L39nLN4dw/Xqv3NxZDj7qc7SezSezZUu1xb8egCFnReDAVz CqCoSI4nfPrxE1ImsFA0wmai//FHmhBcl2tT9x6CiqdNNH6wig /iz5DYBfNAhzg0jdNXinXFt7eKz5xVGKLYL75PmZkWWtU8Qd60 wetsxdVNFN976r2Tbe3FNJoM+8hkJ7ISUK2TMkVoNIKRJ6s6hv 5wUUireP+zg+KwhElh+OjrkBBjw36XvGyF+tWyuEUpIvCpbaWc r5zhaPb0Jwb5FX0JbiuaP3ScFhdlFuGKmbq3fhGC9 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I have exactly the same webcam, lsusb says "Bus 002 Device 004: ID 046d:0826 Logitech, Inc."... On 06.07.2012, Alan Stern wrote: > On Thu, 5 Jul 2012, Frederik Himpe wrote: > > I tried setting to on again, and then this appears in the logs: > > Jul 5 21:21:59 piranha kernel: [ 9788.223118] usb 1-1.2: USB disconnect, device number 6 > > Jul 5 21:22:00 piranha kernel: [ 9788.330415] usb 1-1.2: new full-speed USB device number 7 using ehci_hcd > > Jul 5 21:22:00 piranha kernel: [ 9788.402207] usb 1-1.2: device descriptor read/64, error -32 > > Jul 5 21:22:00 piranha kernel: [ 9788.577706] usb 1-1.2: device descriptor read/64, error -32 > > Jul 5 21:22:00 piranha kernel: [ 9788.753203] usb 1-1.2: new full-speed USB device number 8 using ehci_hcd > > Jul 5 21:22:00 piranha kernel: [ 9788.824996] usb 1-1.2: device descriptor read/64, error -32 > > Jul 5 21:22:00 piranha kernel: [ 9789.000493] usb 1-1.2: device descriptor read/64, error -32 [....] ...and I do not have these messages at all, with or without autosuspend enabled... > In the long run, it may be necessary to add a quirk entry to always > use a reset-resume with this device. You can find similar entries in > drivers/usb/core/quirks.c for other Logitech webcams, which makes it > seem very likely that one is needed for yours. If you want you > can try adding the appropriate entry and submit it as a patch. ...and it runs fine with or without the quirk, which I added for testing purposes. > None of this explains why there isn't any problem when the webcam is > plugged into a USB-3 port, unfortunately. All this is purely on USB-2, my machine doesn't have any USB-3 port, with vanilla 3.4.4 kernel. If nobody did, should I submit a patch containing the quirk anyway? If I can help testing, feel free to contact me.