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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 55181C43461 for ; Wed, 16 Sep 2020 19:29:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DDAFC20936 for ; Wed, 16 Sep 2020 19:29:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="MNVF8Tvc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727663AbgIPT2q (ORCPT ); Wed, 16 Sep 2020 15:28:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51330 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728193AbgIPT1s (ORCPT ); Wed, 16 Sep 2020 15:27:48 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CF9FC061788 for ; Wed, 16 Sep 2020 12:27:18 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id k8so1214044pfk.2 for ; Wed, 16 Sep 2020 12:27:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=sR/xYZr4LEgOrl+IbZ9jlJQDRZY5vQLajnenX9LFols=; b=MNVF8TvcPWY3eeFn4HzT6kU1YkW7DvEZmNLo7UYzumvDpZ4mECWs58glstVCILzfW+ yaY5Ar/3V3T6TrxxrGNtBWUfp2Mh4ZOcb8StDZf0Z7XH6/zRv0WYYyUVFzY5m2Nu1v7p FkL2YwUOGv+fA3lNECNbUWaSIFtnnE0C1krC8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=sR/xYZr4LEgOrl+IbZ9jlJQDRZY5vQLajnenX9LFols=; b=I9IBUJLzGRwuIRRFKJSPQ0CN7pwN0ofj2+bSpHX4rwoOEJgEVOb+I9s7FYJ/GSS5fG wubDfghJTYRCX+yhNioR/GITz3mHNaPkEGsdO/xXggl+EnibbFAPqh3ziEf/LN5byZeY /jHO4e7AN11ilPAsXMTWV1opaPCifSkoWmqvxsIOB8Jypn1WH64Pgnyuis8Obmyy58bC b5eZKlR1Sad8hfRB1GFp5GIoqrMMcqi9KC71WS5k6ImR2u6D8Z+lixIYbLh5q+yF/4VF xocnndstBXYV0Nrsq/TazwiLQ9SQgirImjnIG+2lGgLG+jNvgm8Qqr+Z7BUijsM+qP6G HTsA== X-Gm-Message-State: AOAM533b1qBr7fDhMtp2A937qpdcKI6oBbLTMrmbw+6GzJTKJVHGIgO3 n/C1toFO7H3Q6rP7qjmIJNTjYg== X-Google-Smtp-Source: ABdhPJy0DnJtx4hulvq3KJWtC6BUsatwfwJXaBeWhCGFtsumy/RNBJ1kLXeNp7WDRc9RK+97rX8DRQ== X-Received: by 2002:a05:6a00:1481:b029:142:2501:35d7 with SMTP id v1-20020a056a001481b0290142250135d7mr7928007pfu.55.1600284437582; Wed, 16 Sep 2020 12:27:17 -0700 (PDT) Received: from localhost ([2620:15c:202:1:f693:9fff:fef4:e70a]) by smtp.gmail.com with ESMTPSA id k24sm17799139pfg.148.2020.09.16.12.27.16 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 16 Sep 2020 12:27:17 -0700 (PDT) Date: Wed, 16 Sep 2020 12:27:15 -0700 From: Matthias Kaehlcke To: Alan Stern Cc: Peter Chen , Greg Kroah-Hartman , Rob Herring , Frank Rowand , Krzysztof Kozlowski , Bastien Nocera , Ravi Chandra Sadineni , "linux-usb@vger.kernel.org" , Stephen Boyd , "devicetree@vger.kernel.org" , Douglas Anderson , "linux-kernel@vger.kernel.org" , "Alexander A. Klimov" , Masahiro Yamada Subject: Re: [PATCH 2/2] USB: misc: Add onboard_usb_hub driver Message-ID: <20200916192715.GC3560556@google.com> References: <20200914112716.1.I248292623d3d0f6a4f0c5bc58478ca3c0062b49a@changeid> <20200914112716.2.I7c9a1f1d6ced41dd8310e8a03da666a32364e790@changeid> <20200915025426.GA17450@b29397-desktop> <20200915050207.GF2022397@google.com> <20200915230345.GF2771744@google.com> <20200916021421.GA1024554@rowland.harvard.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200916021421.GA1024554@rowland.harvard.edu> Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Tue, Sep 15, 2020 at 10:14:21PM -0400, Alan Stern wrote: > On Tue, Sep 15, 2020 at 04:03:45PM -0700, Matthias Kaehlcke wrote: > > Hi Peter, > > > > On Tue, Sep 15, 2020 at 07:05:38AM +0000, Peter Chen wrote: > > > > Whether or not it is a wakeup_source, it could get through its or its children's > > > /sys/../power/wakeup value, you have already used usb_wakeup_enabled_descendants > > > to know it. > > > > I conceptually agree, but in practice there are some conflicting details: > > > > wakeup for the hubs on my system is by default disabled, yet USB wakeup works > > regardless, so the flag doesn't really provide useful information. I guess we > > could still use it if there is no better way, but it doesn't seem ideal. > > The wakeup setting for USB hubs affects only the following events: port > connect, port disconnect, and port overcurrent. It does not refer to > forwarding wakeup requests from downstream USB devices; that is always > enabled. So maybe your wakeup flag really is accurate and you didn't > realize it. Thanks for the clarification! > > Similar for udev->bus->controller, according to sysfs it doesn't even have wakeup > > support. Please let me know if there is a reliable way to check if wakeup is > > enabled on the controller of a device. > > The host controller's sysfs wakeup setting should always be correct. If > it isn't, that indicates there is a bug in the host controller driver or > the corresponding platform-specific code. Good to know :) > What driver does your system use? The driver is dwc3-qcom, Peter pointed me to a patch he recently sent to add the missing wakeup entry (https://patchwork.kernel.org/patch/11717835/). It seems that should solve the problem, except for some confusion on my side about the wakeup flag of the xHCI device vs. that of the platform device (details in my reply to Peter).