Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756203AbYCLVpm (ORCPT ); Wed, 12 Mar 2008 17:45:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756154AbYCLVo6 (ORCPT ); Wed, 12 Mar 2008 17:44:58 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:51011 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756149AbYCLVo5 (ORCPT ); Wed, 12 Mar 2008 17:44:57 -0400 Date: Wed, 12 Mar 2008 17:44:56 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Jiri Kosina cc: Tino Keitel , , Subject: Re: broken access to a USB HID device after suspend In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1895 Lines: 48 On Wed, 12 Mar 2008, Jiri Kosina wrote: > On Wed, 12 Mar 2008, Tino Keitel wrote: > > > I use a tool called hidmon to control the parameters of my LCD in shell > > scripts. I just had the case where this tool didn't work after suspend > > to RAM. I just got this error message: > > > > hid_force_open failed with return code 13 > > > > The kernel log contains lines like this: > > > > usb 1-1.3: usbfs: USBDEVFS_CONTROL failed cmd hidmon rqt 129 rq 6 len 9 ret -110 > > > > Unplugging and replugging the USB cable of the LCD didn't work. > > However, after a further suspend/resume cycle it works. > > > > This is Linux 2.6.25-rc5. The behaviour is not repoducible, though. > > However, I just mention it for the case that this might ring a bell > > somewhere. > > This in fact looks like a problem with usbdevfs and/or libusb library, not > the in-kernel HID drvier. > > Did this work before? In 2.6.24? 2.6.23? Alan (added to CC, as well as USB > devel mailinglist) has been doing some changes to usbdevfs to make it > suspend-aware, if I recall correctly. No, usbfs hasn't undergone any significant changes recently. Tino, it would help to see a kernel log showing what happened during the suspend, resume, and failure of hidmon. It would help even more if you test under a kernel with CONFIG_USB_DEBUG enabled. Even if you can't reproduce the problem, do you have the complete kernel log from before? Is it possible that this is really a problem with the LCD device, not with the kernel? I ask because if the device was working properly then unplugging and replugging the USB cable should do a complete reset. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/