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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 60E77C282CE for ; Tue, 4 Jun 2019 22:32:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3DCD22067C for ; Tue, 4 Jun 2019 22:32:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726312AbfFDWcf (ORCPT ); Tue, 4 Jun 2019 18:32:35 -0400 Received: from vimdzmsp-nwas04.bluewin.ch ([195.186.228.51]:33634 "EHLO vimdzmsp-nwas04.bluewin.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726269AbfFDWcf (ORCPT ); Tue, 4 Jun 2019 18:32:35 -0400 X-Greylist: delayed 360 seconds by postgrey-1.27 at vger.kernel.org; Tue, 04 Jun 2019 18:32:32 EDT Received: from mail.osk.ch ([188.62.190.74]) by vimdzmsp-nwas04.bluewin.ch Swisscom AG with SMTP id YHswh8B8mSONSYHt1hU7dU; Wed, 05 Jun 2019 00:26:31 +0200 Received: from server.osk.ch (localhost [127.0.0.1]) by mail.osk.ch (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id x54MQPYn025458 for ; Wed, 5 Jun 2019 00:26:25 +0200 Received: (from osk@localhost) by server.osk.ch (8.14.4/8.14.4/Submit) id x54MQPgU025457 for linux-usb@vger.kernel.org; Wed, 5 Jun 2019 00:26:25 +0200 X-Authentication-Warning: server.osk.ch: osk set sender to usb@osk.ch using -f Date: Wed, 5 Jun 2019 00:26:25 +0200 From: Chris Osicki To: linux-usb@vger.kernel.org Subject: Question: Device not recognized when connected without a hub. Why? Message-ID: <20190604222625.GA25390@server> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-message-flag: Using Microsoft software might be a security risk User-Agent: Mutt/1.5.23 (2014-03-12) X-Greylist: inspected by milter-greylist-4.5.11 (mail.osk.ch [127.0.0.1]); Wed, 05 Jun 2019 00:26:26 +0200 (CEST) for IP:'127.0.0.1' DOMAIN:'localhost' HELO:'server.osk.ch' FROM:'usb@osk.ch' RCPT:'' X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.11 (mail.osk.ch [127.0.0.1]); Wed, 05 Jun 2019 00:26:26 +0200 (CEST) X-CMAE-Envelope: MS4wfNwnR2n5jWx4t+3QHPifpQUQ1x7HUSjFuGK/mGKw/2JRa1jaL1fK5P6f7lAzLFRKfeyVFDRsBUuU/lWwF3iCw6p7T+LA9X5/MuyP+bS1hxdWYrFqvBuc 6ddkB6Q+dhFJTsbvC2odSYH1c7tPNxG988/eXocu7S3PeEtnP5MzJgAl Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi I stumbled over a behaviour when connecting a USB device which I couldn't find any explanation for. So, I'm trying here. Why connecting a USB device (USB-TTL converter) direct and via an USB hub makes a difference? When I connect it directly all I see in /var/log/syslog are errors, when connectedd via a USB-hub it works as expected. See logs below. hp8300 is HP Compaq Elite 8300 SFF (QV996AV), kernel: 4.15.0-50-generic #54-Ubuntu lshw reports: *-usb:0 description: USB controller product: 7 Series/C210 Series Chipset Family USB xHCI Host Controller vendor: Intel Corporation *-usb:1 description: USB controller product: 7 Series/C216 Chipset Family USB Enhanced Host Controller #2 vendor: Intel Corporation BTW, it does work as expected on a Lenovo x220 (same OS). Let me know if I should provide any more information. Thanks in advance for any hint. Regards, Chris Connected directly: Jun 4 23:26:44 hp8300 kernel: [218215.233450] usb 1-1.1: new full-speed USB device number 34 using ehci-pci Jun 4 23:26:44 hp8300 kernel: [218215.313423] usb 1-1.1: device descriptor read/64, error -32 Jun 4 23:26:44 hp8300 kernel: [218215.501445] usb 1-1.1: device descriptor read/64, error -32 Jun 4 23:26:44 hp8300 kernel: [218215.689444] usb 1-1.1: new full-speed USB device number 35 using ehci-pci Jun 4 23:26:44 hp8300 kernel: [218215.769443] usb 1-1.1: device descriptor read/64, error -32 Jun 4 23:26:44 hp8300 kernel: [218215.957429] usb 1-1.1: device descriptor read/64, error -32 Jun 4 23:26:44 hp8300 kernel: [218216.065626] usb 1-1-port1: attempt power cycle Jun 4 23:26:45 hp8300 kernel: [218216.669420] usb 1-1.1: new full-speed USB device number 36 using ehci-pci Jun 4 23:26:45 hp8300 kernel: [218217.085412] usb 1-1.1: device not accepting address 36, error -32 Jun 4 23:26:45 hp8300 kernel: [218217.165414] usb 1-1.1: new full-speed USB device number 37 using ehci-pci Jun 4 23:26:46 hp8300 kernel: [218217.581413] usb 1-1.1: device not accepting address 37, error -32 Jun 4 23:26:46 hp8300 kernel: [218217.581574] usb 1-1-port1: unable to enumerate USB device Connected via a simple USB hub: Jun 4 23:28:08 hp8300 kernel: [218300.044754] usb 1-1.1: new full-speed USB device number 38 using ehci-pci Jun 4 23:28:08 hp8300 kernel: [218300.161948] usb 1-1.1: New USB device found, idVendor=058f, idProduct=9254 Jun 4 23:28:08 hp8300 kernel: [218300.161950] usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0 Jun 4 23:28:08 hp8300 kernel: [218300.161951] usb 1-1.1: Product: Generic USB Hub Jun 4 23:28:08 hp8300 kernel: [218300.161952] usb 1-1.1: Manufacturer: ALCOR Jun 4 23:28:08 hp8300 kernel: [218300.162269] hub 1-1.1:1.0: USB hub found Jun 4 23:28:08 hp8300 kernel: [218300.162936] hub 1-1.1:1.0: 4 ports detected Jun 4 23:28:08 hp8300 upowerd[2750]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.0 Jun 4 23:28:08 hp8300 upowerd[2750]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1 Jun 4 23:28:09 hp8300 kernel: [218300.448772] usb 1-1.1.1: new full-speed USB device number 39 using ehci-pci Jun 4 23:28:09 hp8300 kernel: [218300.557969] usb 1-1.1.1: New USB device found, idVendor=1a86, idProduct=7523 Jun 4 23:28:09 hp8300 kernel: [218300.557973] usb 1-1.1.1: New USB device strings: Mfr=0, Product=2, SerialNumber=0 Jun 4 23:28:09 hp8300 kernel: [218300.557975] usb 1-1.1.1: Product: USB2.0-Serial Jun 4 23:28:09 hp8300 mtp-probe: checking bus 1, device 39: "/sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1.1" Jun 4 23:28:09 hp8300 mtp-probe: bus: 1, device: 39 was not an MTP device Jun 4 23:28:09 hp8300 kernel: [218300.590591] usbcore: registered new interface driver ch341 Jun 4 23:28:09 hp8300 kernel: [218300.590602] usbserial: USB Serial support registered for ch341-uart Jun 4 23:28:09 hp8300 kernel: [218300.590614] ch341 1-1.1.1:1.0: ch341-uart converter detected Jun 4 23:28:09 hp8300 kernel: [218300.591377] usb 1-1.1.1: ch341-uart converter now attached to ttyUSB0