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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 26DE8C282DD for ; Fri, 10 Jan 2020 16:36:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ED6A2205F4 for ; Fri, 10 Jan 2020 16:36:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728529AbgAJQgo (ORCPT ); Fri, 10 Jan 2020 11:36:44 -0500 Received: from iolanthe.rowland.org ([192.131.102.54]:42858 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1728492AbgAJQgo (ORCPT ); Fri, 10 Jan 2020 11:36:44 -0500 Received: (qmail 4548 invoked by uid 2102); 10 Jan 2020 11:36:43 -0500 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 10 Jan 2020 11:36:43 -0500 Date: Fri, 10 Jan 2020 11:36:43 -0500 (EST) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Kai-Heng Feng cc: Mathias Nyman , Greg Kroah-Hartman , AceLan Kao , USB list , LKML Subject: Re: [PATCH v2 3/3] USB: Disable LPM on WD19's Realtek Hub In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Fri, 10 Jan 2020, Kai-Heng Feng wrote: > On Fri, Jan 10, 2020 at 11:40 PM Alan Stern wrote: > > > > On Fri, 10 Jan 2020, Kai-Heng Feng wrote: > > > > > Realtek Hub (0bda:0x0487) used in Dell Dock WD19 sometimes drops off the > > > bus when bringing underlying ports from U3 to U0. > > > > > > Disabling LPM on the hub during setting link state is not enough, so > > > let's disable LPM completely for this hub. > > > > > > Signed-off-by: Kai-Heng Feng > > > --- > > > drivers/usb/core/quirks.c | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > > > diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c > > > index 6b6413073584..2fb7c1602280 100644 > > > --- a/drivers/usb/core/quirks.c > > > +++ b/drivers/usb/core/quirks.c > > > @@ -371,6 +371,9 @@ static const struct usb_device_id usb_quirk_list[] = { > > > { USB_DEVICE(0x0b05, 0x17e0), .driver_info = > > > USB_QUIRK_IGNORE_REMOTE_WAKEUP }, > > > > > > + /* Realtek hub in Dell WD19 (Type-C) */ > > > + { USB_DEVICE(0x0bda, 0x0487), .driver_info = USB_QUIRK_NO_LPM }, > > > + > > > /* Action Semiconductor flash disk */ > > > { USB_DEVICE(0x10d6, 0x2200), .driver_info = > > > USB_QUIRK_STRING_FETCH_255 }, > > > > > > > This is a very partial patch. There were four hunks in the original > > version but there's only one hunk in V2. > > Because the original approach is insufficient, it significantly > reduced the fail rate but the issue is still there. > USB_QUIRK_NO_LPM is used instead so no other parts are needed. Oh, all right. This change looks okay to me. Has AceLan Kao tested it? Alan Stern