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 624C9C433E0 for ; Wed, 10 Jun 2020 15:43:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4618C2072F for ; Wed, 10 Jun 2020 15:43:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730271AbgFJPnx convert rfc822-to-8bit (ORCPT ); Wed, 10 Jun 2020 11:43:53 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:43313 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726955AbgFJPnx (ORCPT ); Wed, 10 Jun 2020 11:43:53 -0400 Received: from mail-pg1-f200.google.com ([209.85.215.200]) by youngberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jj2tL-0003XM-Ff for linux-kernel@vger.kernel.org; Wed, 10 Jun 2020 15:43:51 +0000 Received: by mail-pg1-f200.google.com with SMTP id x186so1723465pgb.6 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=mqCR3i4kxcrOn1yzh+SeT19hXYESrSGU+Z0taf19VfZWjT+fUA76HQRlgDqkkHSzuo lPTLQfITPGPCT5YPXpoiBRu+D8p2/Q8/Z66t0FU3s4zn7X1aBfGQp/Jnj/vO6YpxyB7m jUtm0h1fDTaSLgiT6r2zHpxfELKQDt+td7bJ0Nn/bkbjeGKvzZHQW2kdYwpgDAwj75MP hBHq4tvOIzgQow4FfqmVCRC2jNTh/uGyk3sHqhrbK23CwrZ6M77DWWa9Tord8VgzvnJ6 A/LW4sizXpX0Us0odBG0J/NY2pwIDE5UAQRkiRp8r9cbyewugv+V8OYOMsoF7hk4lycI RpbA== X-Gm-Message-State: AOAM533xEU3LVxr2Y2JXGIAxcmP/qdejoY71yL63/12gE1v/LZfvoBDg sw3DdyDysmRznRQwz1610ZtmKtmc+WpVOP81yRyLN8Q+Mu+S7Dlt/X2yLjNtOWiUvthxo++EDS/ tMAqoG2/249FkA06d7nC5x+cTWYnRrkltvlT+aFn3ng== X-Received: by 2002:a65:6446:: with SMTP id s6mr3249826pgv.59.1591803830125; 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-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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