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=-5.6 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 E8E55C433DB for ; Sat, 27 Feb 2021 03:49:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9F7DE64F17 for ; Sat, 27 Feb 2021 03:49:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230018AbhB0DtD (ORCPT ); Fri, 26 Feb 2021 22:49:03 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:12215 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229863AbhB0Ds7 (ORCPT ); Fri, 26 Feb 2021 22:48:59 -0500 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4DnXWB3t50zlHL9; Sat, 27 Feb 2021 11:46:14 +0800 (CST) Received: from [10.67.102.118] (10.67.102.118) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.498.0; Sat, 27 Feb 2021 11:48:12 +0800 Subject: Re: [RFC PATCH] USB:XHCI:Modify XHCI driver for USB2.0 controller From: liulongfang To: Alan Stern CC: , , , , References: <1614327697-1021-1-git-send-email-liulongfang@huawei.com> <20210226163004.GB1392547@rowland.harvard.edu> Message-ID: <7e880f79-8568-7b14-cb2f-4be647538ba1@huawei.com> Date: Sat, 27 Feb 2021 11:48:12 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="gbk" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.102.118] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/2/27 11:38, liulongfang wrote: > On 2021/2/27 0:30, Alan Stern wrote: >> On Fri, Feb 26, 2021 at 04:21:37PM +0800, Longfang Liu wrote: >>> Our current XHCI hardware controller has been customized to only >>> support USB 2.0 ports. When using the current xhci driver, an xhci >>> controller device and an ehci controller device will be created >>> automatically. >> >> That sentence makes no sense at all. An EHCI controller device is a >> piece of hardware. How can an xHCI driver, which is a piece of >> software, create a piece of hardware? >> >> Alan Stern >> . >> > The hardware device is a complete USB3.0 controller, On the hardware, only the hardware connection of the USB2.0 port has been opened > but I hope to support a USB2.0-only mode through software configuration. > Thanks. > Longfang Liu > . > Thanks. Longfang Liu