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=-0.8 required=3.0 tests=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 19D96C433E0 for ; Wed, 10 Jun 2020 15:43:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F063220823 for ; Wed, 10 Jun 2020 15:43:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730279AbgFJPn4 convert rfc822-to-8bit (ORCPT ); Wed, 10 Jun 2020 11:43:56 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:43315 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727910AbgFJPnx (ORCPT ); Wed, 10 Jun 2020 11:43:53 -0400 Received: from mail-pg1-f197.google.com ([209.85.215.197]) by youngberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jj2tL-0003XO-Lu for linux-usb@vger.kernel.org; Wed, 10 Jun 2020 15:43:51 +0000 Received: by mail-pg1-f197.google.com with SMTP id m15so1711320pgl.15 for ; Wed, 10 Jun 2020 08:43:51 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=pIEJ2ejVSoH3NHNxiiH0JO+dQepzCs9hxzeYyLsKYnE=; b=kHh7S+l/VVArwStr20zovCCnmsy+BBcEYq3xXNc+voR850DKesd/L82Z4sYrzeXuP/ 0He7wWA/uFgi2avp5RmKCjJ3CSg5L1fhfIQRNZXl0Yaiz7WpOAEY0DmXAIktE7Scq07p N56SsJ0fVS182XjwzbcVpuc12MpN/VCZTpUnOmJJ9OY6VFaiyYnFNrDB1Qi2P4v4clli AIHFX8pvAAFrm5JN6xZK5sHhPoeDL4okqqix2p0K7PhE5Kxaplw1LrgasVQyj4zz18Nh HqEIIzbuZn1oQ+nFuz5+bD+E678H5sTemt17mxi+OEjeXykPTmYT3XM30kMbazfsGSAG 8GoQ== X-Gm-Message-State: AOAM532g+jro7GDWCpPi65/Kg2OdlsMZS3p6gVgUzXFtNcwy0jCE7rcW 6dcejCutXfV0mYAw23Ptb/zPDlfsoFYOgesiOOPMTGEfzOAXUrFt3MFLjDRMAeaCAh1byc2ZjXy viQ82/UOLvhqC4F3DMKd5n4TUehUVIkLTUhfR0Q== X-Received: by 2002:a65:6446:: with SMTP id s6mr3249825pgv.59.1591803830124; Wed, 10 Jun 2020 08:43:50 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxsEfzhKGoIHjpkOEW5GETqwgNMAaWSKvOESWqkOMSTCehmvPiglPaqM0tVbdoshUenRPFCjw== X-Received: by 2002:a65:6446:: with SMTP id s6mr3249805pgv.59.1591803829731; Wed, 10 Jun 2020 08:43:49 -0700 (PDT) Received: from [192.168.1.208] (220-133-187-190.HINET-IP.hinet.net. [220.133.187.190]) by smtp.gmail.com with ESMTPSA id y23sm230676pgc.78.2020.06.10.08.43.48 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 10 Jun 2020 08:43:49 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.80.23.2.2\)) Subject: Re: [PATCH 1/2] xhci: Suspend ports to U3 directly from U1 or U2 From: Kai-Heng Feng In-Reply-To: <20200610143220.GC11727@rowland.harvard.edu> Date: Wed, 10 Jun 2020 23:43:46 +0800 Cc: Mathias Nyman , Greg Kroah-Hartman , "open list:USB XHCI DRIVER" , open list Content-Transfer-Encoding: 8BIT Message-Id: <591D2A1F-9645-4B0B-896C-99544F06DFAA@canonical.com> References: <20200610064231.9454-1-kai.heng.feng@canonical.com> <20200610143220.GC11727@rowland.harvard.edu> To: Alan Stern X-Mailer: Apple Mail (2.3608.80.23.2.2) Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org > On Jun 10, 2020, at 22:32, Alan Stern wrote: > > On Wed, Jun 10, 2020 at 02:42:30PM +0800, Kai-Heng Feng wrote: >> xHCI spec "4.15.1 Port Suspend" states that port can be put to U3 as long >> as Enabled bit is set and from U0, U1 or U2 state. >> >> Currently only USB_PORT_FEAT_LINK_STATE puts port to U3 directly, let's >> do the same for USB_PORT_FEAT_SUSPEND and bus suspend case. >> >> This is particularly useful for USB2 devices, which may take a very long >> time to switch USB2 LPM on and off. > > Have these two patches been tested with a variety of USB-2.0 and USB-2.1 > devices? I tested some laptops around and they work fine. Only internally connected USB devices like USB Bluetooth and USB Camera have USB2 LPM enabled, so this patch won't affect external connected devices. Kai-Heng > > Alan Stern