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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 15E11C433B4 for ; Thu, 22 Apr 2021 11:08:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBE5861452 for ; Thu, 22 Apr 2021 11:08:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235863AbhDVLIv (ORCPT ); Thu, 22 Apr 2021 07:08:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230285AbhDVLIv (ORCPT ); Thu, 22 Apr 2021 07:08:51 -0400 Received: from rin.romanrm.net (rin.romanrm.net [IPv6:2001:bc8:2dd2:1000::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8EAA1C06174A for ; Thu, 22 Apr 2021 04:08:16 -0700 (PDT) Received: from natsu (natsu2.home.romanrm.net [IPv6:fd39::e99e:8f1b:cfc9:ccb8]) by rin.romanrm.net (Postfix) with SMTP id 11A95713; Thu, 22 Apr 2021 11:08:12 +0000 (UTC) Date: Thu, 22 Apr 2021 16:08:13 +0500 From: Roman Mamedov To: Greg KH Cc: linux-usb@vger.kernel.org Subject: Re: Not enough bandwidth for new device state -- with Etron USB3 controller only Message-ID: <20210422160813.41e26426@natsu> In-Reply-To: References: <20210421223732.27080321@natsu> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hello, On Thu, 22 Apr 2021 07:49:38 +0200 Greg KH wrote: > Not a bug, this is how USB works. Your first hub really does not have > enough bandwidth for that device. Well, we think it doesn't, the > calculation for that is really really tricky and we error on the side of > "let's not take the risk and just disable the device to be safe". > > Get a better hub :) But why the calculation is different when the hub is plugged into the onboard USB 2.0 controller -- and there it works? I hope you don't take this as a bug report to make it stop working there as well. :) If it's because the Etron controller is USB 3.0, and the higher speeds are somehow accounted for in the bandwidth calculation, that doesn't seem right, since both of the plugged in downstream hubs are 1.1/2.0-only. -- With respect, Roman