From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E97FC47082 for ; Tue, 8 Jun 2021 19:01:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 59D3260FEF for ; Tue, 8 Jun 2021 19:01:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236925AbhFHTDf (ORCPT ); Tue, 8 Jun 2021 15:03:35 -0400 Received: from netrider.rowland.org ([192.131.102.5]:60965 "HELO netrider.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S236736AbhFHSzI (ORCPT ); Tue, 8 Jun 2021 14:55:08 -0400 Received: (qmail 1814829 invoked by uid 1000); 8 Jun 2021 14:53:14 -0400 Date: Tue, 8 Jun 2021 14:53:14 -0400 From: Alan Stern To: Larry Finger Cc: linux-usb@vger.kernel.org, LKML , ierturk@ieee.org Subject: Re: Strange problem with USB device Message-ID: <20210608185314.GB1812516@rowland.harvard.edu> References: <20210608182038.GA1812516@rowland.harvard.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 08, 2021 at 01:37:07PM -0500, Larry Finger wrote: > On 6/8/21 1:20 PM, Alan Stern wrote: > > One thing you might try is to turn on USB debugging before > > plugging in the device: > > > > echo 'module usbcore =p' >/sys/kernel/debug/dynamic_debug/control > > > > The additional information this adds to the dmesg log may be > > helpful. > > The BT device is part of the same card as the PCIe wifi device, thus > there is no "plugging" it in a conventional sense. I don't get it. If this is a PCIe device, why should it appear on a USB bus? Wouldn't you expect it to show up as a PCI device on a PCI bus instead? > Is there some way to > add the usbcore debugging statement to the kernel options line at boot > time? Yes. Use the kernel boot-line parameter: usbcore.dyndbg="=p" FYI, how to use dynamic debugging is explained at length in the kernel source file Documentation/admin-guide/dynamic-debug-howto.rst. Alan Stern > As I told GregKH, I am having the person with the problem try a rescue > system with a 5.12 kernel. > > Larry >